This patent discloses a waste treatment system that uses primary treatment, aeration of the waste in an equalization tank, and application of the waste to a rotating disk biological reactor. The rotating disk reactor contains a plurality of disks made of thin wedge-shaped elements that can be tightly packed for shipping but spaced apart when assembled, allowing biological slime to form on the surfaces. This arrangement improves on prior rotating disk reactors by making the disks easier and cheaper to transport and assemble.
Construction,operation and maintenance of trickling filter2Shivamsanoo
The document discusses the construction, operation, and maintenance of trickling filters. It describes the technology, materials, and analysis used in construction. It explains the biology of bacteria and microorganisms involved in operation. Maintenance requires periodic washing to prevent clogging and monitoring by a skilled operator. Designs can include one-stage or two-stage filters. Advantages include high nitrification and good dependability, while disadvantages include head loss and high costs.
The document provides an overview of biodisc characteristics for wastewater treatment and discusses their design and operation. Biodiscs consist of rotating plastic discs partially submerged in a tank, with microorganisms adhered to the surface that degrade organic matter in wastewater. Well-operated biodiscs can remove 80-95% of organic matter and nitrify wastewater. Design considerations include disc material, configuration, and biofilm thickness. Biodiscs have advantages like flexibility, low energy use, and the ability to treat variable flows.
This document provides an overview of various biological wastewater treatment processes, including activated sludge treatment, aerobic granular sludge, surface aerated basins, trickling filters, constructed wetlands, biological aerated filters, rotating biological contactors, membrane bioreactors, secondary sedimentation, tertiary treatments like filtration and nutrient removal processes, and disinfection. The key stages in wastewater treatment involve using microorganisms and oxygen to break down organic matter, nutrients, and pathogens in primary, secondary, and tertiary treatment before disinfected effluent is discharged or reused.
This document reviews the applicability and design of sequencing batch reactors (SBRs) for wastewater treatment. It discusses how SBRs can be modified to treat different types of wastewater more efficiently than conventional activated sludge processes. The review finds that SBRs can effectively treat municipal, industrial, synthetic, and piggery wastewaters through various cycle phases and operating conditions. SBRs have been shown to achieve high removal rates of pollutants like biochemical oxygen demand, total suspended solids, nutrients, and heavy metals from different wastewaters. The document examines several lab-scale and pilot-scale studies that demonstrate SBRs' treatment performance and ability to be optimized for different wastewater compositions.
This document discusses vermifiltration, a low-cost wastewater treatment technique using earthworms. It describes how earthworms and their gut microbes remove 90% or more of BOD, COD, TDS and TSS from wastewater through ingestion and biodegradation. The document outlines the vermifiltration process, comparing it to a control biofilter bed without worms. It also lists several advantages of vermifiltration over conventional wastewater treatment, such as low energy needs, value-added vermicompost byproduct, and no foul odors.
The document discusses constructed wetlands for treating wastewater. It describes experiments conducted on constructed wetlands along Bilbeas Drain and Lake Manzala in Egypt. Pilot wetland systems were set up, including a surface flow system with cattail plants and a combined surface-subsurface flow system with cattail and water hyacinth plants. Water quality parameters were analyzed for the inflow and outflow of the wetlands. The experiments aimed to investigate the wetlands' ability to enhance drain water quality and the effects of different design parameters on treatment performance.
This document summarizes a study on the microbial communities in a full-scale vermifilter (VF) system treating rural domestic sewage in China over 17 months. The VF system achieved average removal efficiencies of 67.6% for COD, 78.0% for BOD5, 92.1% for NH4+-N, and 89.8% for TSS. Phylogenetic analysis of 16S rRNA gene sequences revealed that the VF biofilm was dominated by Proteobacteria, especially gamma-proteobacteria, followed by Acidobacteria, Bacteroidetes, and Planctomycetes. Earthworm activity in the VF selected for microbes related to processes in earthworm guts
Review of research on bio reactors used in wastewater ijsit 2.4.6IJSIT Editor
This document reviews various types of bioreactors used in wastewater treatment for biohydrogen production, including batch, continuous stirred tank, plug flow, biofilm, suspended growth, upflow anaerobic sludge blanket, anaerobic baffled, upflow packed bed, fluidized bed, sequencing batch, and membrane separation reactors. It discusses the operating principles and advantages/limitations of these different reactor configurations. The review concludes that significant progress has been made in developing advanced high-rate anaerobic reactors to improve wastewater treatment efficiency and biogas production for hydrogen fuel applications.
Construction,operation and maintenance of trickling filter2Shivamsanoo
The document discusses the construction, operation, and maintenance of trickling filters. It describes the technology, materials, and analysis used in construction. It explains the biology of bacteria and microorganisms involved in operation. Maintenance requires periodic washing to prevent clogging and monitoring by a skilled operator. Designs can include one-stage or two-stage filters. Advantages include high nitrification and good dependability, while disadvantages include head loss and high costs.
The document provides an overview of biodisc characteristics for wastewater treatment and discusses their design and operation. Biodiscs consist of rotating plastic discs partially submerged in a tank, with microorganisms adhered to the surface that degrade organic matter in wastewater. Well-operated biodiscs can remove 80-95% of organic matter and nitrify wastewater. Design considerations include disc material, configuration, and biofilm thickness. Biodiscs have advantages like flexibility, low energy use, and the ability to treat variable flows.
This document provides an overview of various biological wastewater treatment processes, including activated sludge treatment, aerobic granular sludge, surface aerated basins, trickling filters, constructed wetlands, biological aerated filters, rotating biological contactors, membrane bioreactors, secondary sedimentation, tertiary treatments like filtration and nutrient removal processes, and disinfection. The key stages in wastewater treatment involve using microorganisms and oxygen to break down organic matter, nutrients, and pathogens in primary, secondary, and tertiary treatment before disinfected effluent is discharged or reused.
This document reviews the applicability and design of sequencing batch reactors (SBRs) for wastewater treatment. It discusses how SBRs can be modified to treat different types of wastewater more efficiently than conventional activated sludge processes. The review finds that SBRs can effectively treat municipal, industrial, synthetic, and piggery wastewaters through various cycle phases and operating conditions. SBRs have been shown to achieve high removal rates of pollutants like biochemical oxygen demand, total suspended solids, nutrients, and heavy metals from different wastewaters. The document examines several lab-scale and pilot-scale studies that demonstrate SBRs' treatment performance and ability to be optimized for different wastewater compositions.
This document discusses vermifiltration, a low-cost wastewater treatment technique using earthworms. It describes how earthworms and their gut microbes remove 90% or more of BOD, COD, TDS and TSS from wastewater through ingestion and biodegradation. The document outlines the vermifiltration process, comparing it to a control biofilter bed without worms. It also lists several advantages of vermifiltration over conventional wastewater treatment, such as low energy needs, value-added vermicompost byproduct, and no foul odors.
The document discusses constructed wetlands for treating wastewater. It describes experiments conducted on constructed wetlands along Bilbeas Drain and Lake Manzala in Egypt. Pilot wetland systems were set up, including a surface flow system with cattail plants and a combined surface-subsurface flow system with cattail and water hyacinth plants. Water quality parameters were analyzed for the inflow and outflow of the wetlands. The experiments aimed to investigate the wetlands' ability to enhance drain water quality and the effects of different design parameters on treatment performance.
This document summarizes a study on the microbial communities in a full-scale vermifilter (VF) system treating rural domestic sewage in China over 17 months. The VF system achieved average removal efficiencies of 67.6% for COD, 78.0% for BOD5, 92.1% for NH4+-N, and 89.8% for TSS. Phylogenetic analysis of 16S rRNA gene sequences revealed that the VF biofilm was dominated by Proteobacteria, especially gamma-proteobacteria, followed by Acidobacteria, Bacteroidetes, and Planctomycetes. Earthworm activity in the VF selected for microbes related to processes in earthworm guts
Review of research on bio reactors used in wastewater ijsit 2.4.6IJSIT Editor
This document reviews various types of bioreactors used in wastewater treatment for biohydrogen production, including batch, continuous stirred tank, plug flow, biofilm, suspended growth, upflow anaerobic sludge blanket, anaerobic baffled, upflow packed bed, fluidized bed, sequencing batch, and membrane separation reactors. It discusses the operating principles and advantages/limitations of these different reactor configurations. The review concludes that significant progress has been made in developing advanced high-rate anaerobic reactors to improve wastewater treatment efficiency and biogas production for hydrogen fuel applications.
Domestic Wastewater Treatment by Root Zone Technology Option: Colacassia PlantDr. Amarjeet Singh
Root Zone Technology is one of the low cost
methods to treat wastewater. With the help of this system we
can treat the Non-Point sources with best results. To achieve
this goal we have to divide the Non-Point sources into
constructed channels within the river bank followed by root
zone bed or if the Non-Point Sources is coming from natural
nallas we can provide this system within its Channel. We
have prepared channel on which I have developed the root
zone bed and have lab analysis of rector out put on number
of parameters. Flow rate and Detention time are the two
factors on which channels are to be designed. Therefore I
am changing the flow rate and finding out the change in
parameter with respect to detection time. The optimization
is when we get best result with maximum flow. I have got
satisfactory results for the detention time of Three day,
Seven day and twenty one day and Three day. With the help
of this data I have designed the root zone bed system for the
selected actual Domestic Sources.
Objectives :-
* Characterization and study of biochar.
*To examine biochar adsorption capacity.
*To determine the effect of KMnO4 as modifying agent on biochar adsorption.
1) Sewage treatment plants are necessary to purify wastewater before discharge into rivers or oceans. They employ natural biological processes to break down pollutants.
2) The typical sewage treatment process has four stages: primary treatment to remove solids; secondary biological treatment using microorganisms to oxidize compounds; secondary settling; and tertiary treatment if needed before discharge.
3) Common secondary treatment methods are biological filtration using media to support microbe growth, activated sludge using aeration to sustain microbes, and Pasveer Ditches which circulate and aerate sewage.
There is an intrinsic connection between biodiversity conservation, water and sanitation. With appropriate technologies, wastewater can be treated to produce fit-for-purpose water with recovery of nutrients to enhance biodiversity conservation in terms of flora and fauna. This project highlights a pilot subsurface flow Constructed Wetland unit in order to identify its performance in treating domestic wastewater and in recovering nutrients.
The project won the 1st Prize in National Quarry Life Award in 2012 in Tanzania.
Read more: http://www.quarrylifeaward.com/project/integrated-constructed-wetland-wastewater-treatment-rainwater-harvesting-nutrient-recovery
This document describes a study on treating synthetic wastewater using an activated sludge process in a laboratory-scale jet loop reactor. The researchers tested COD (chemical oxygen demand) removal efficiency at different mixed liquor volatile suspended solids (MLVSS) concentrations and a hydraulic retention time of 60 minutes. They found that over 95% COD removal could be achieved with an MLVSS of 3000 mg/L. Tables of results show COD levels decreasing over 5 hours as MLVSS increased from 1000 mg/L to 3000 mg/L. Graphs illustrate the relationships between time and COD or MLVSS. The reactor demonstrated high wastewater treatment efficiency under the conditions tested.
This document is the preface and table of contents for the Advanced Activated Sludge Study Guide published by the Wisconsin Department of Natural Resources in December 2010. It provides an overview of the guide and outlines its contents, which include chapters on theory and principles, operation and maintenance, monitoring and process control, safety and regulations, and calculations relevant to advanced activated sludge processes. It acknowledges the workgroup that developed the study guide objectives and exam questions.
biological treatment i activated sludge processManish Goyal
The activated sludge process uses microorganisms to biologically treat wastewater. Wastewater enters an aeration tank where microbes consume organic matter, producing new cells and reducing biochemical oxygen demand. Mixed liquor flows to a clarifier where microbes are separated from treated water; some microbes are recycled to the aeration tank while excess sludge is wasted. The process reduces organic matter through microbial growth and substrate utilization under aerobic conditions.
The document presents a model for trickling filter process design. It describes Eckenfelder's pseudo-first-order reaction performance equation for substrate removal rate. The equation relates substrate concentration over time to rate constant, substrate concentration, and contact time. Contact time depends on filter depth and surface loading rate. The model is used to design a trickling filter with a given influent BOD, required effluent BOD, flow rate, filter depth, and removal rate constant to achieve the surface loading rate needed.
Wastewater treatment by vermi filtration technologyvivatechijri
Vermifiltration units are sludge-free, noise-free and low- or no-electricity-requiring systems of
operation. The aim of this study was to emphasize wastewater treatment by vermifiltration technology using
waste-eater earthworms to highlight the benefits of clean and nutritive vermifiltered water (vermiaqua) uses in
agriculture to the farmers. They work on natural capacity of earthworms to treat wastewater from different
sources. In view of rising concern about pollution of water bodies due to discharge of waste in them, it is
necessary to initiate alternative thinking as conventional methods through STPs (Sewage treatment Plants) have
had limited success. In recent years the application of specifically designed filtration based technology
(popularly known as Vermifiltration technology) for treatment of wastewater municipal, urban and agricultural,
is becoming widely acceptable. It treats the wastewater in natural manner without the use of chemicals. In
short, Vermifiltration technology is an improved filtration system for treatment of wastewater. The main
objective of present research work is to provide and popularize a simple, feasible, practically sound, ecofriendly and cost effective technology for wastewater treatment. Vermifiltration technology is such a type of
system, which reduces the impact of sewage and converts into useful water for gardening and irrigation
purpose.
Recycling waste through constructed wetlandBineet Chhajer
The document summarizes a 3-day training program on technologies for waste recycling and sustainable development, including water sensitive plumbing and constructed wetlands. It discusses contemporary issues like limited water resources, increasing waste generation and air pollution in cities. It provides examples of constructed wetland projects in Barcelona, Pune, Delhi, Agra, and Kolkata that treat wastewater and restore the environment. Water sensitive techniques like low-flow toilets and showers, sensor taps, and aerated flow restrictors are presented as ways to reduce residential water usage. The training emphasizes decentralizing waste management through neighborhood-level solutions and integrating ecology and landscape.
“Study The Different Parameters of Sewage Treatment With UASB & SBR Technolog...IOSR Journals
Abstract: Every community produces both liquid and solid wastes and air emissions. The liquid wastewastewater-is
essentially the water supply of the community after it has been used in a variety of applications.
From the standpoint of sources of generation, wastewater may be defined as a combination of the liquid or
water-carried wastes removed from residences, institutions, commercial and industrial establishments, together
with such groundwater, surfacewater and stromwater as may be present. This waste water through sewer comes
to the sewage treatment plant so that parameters are reduced and treated wastewater be disposed into water or
land. For treating the sewage UASB( UP FLOW ANAEROBIC SLUDGE BLANKET) and SBR(SEQUENCING
BATCH REACTOR) technologies are mostly used.
All the parameters of these samples were analyzed using standard methods prescribed in “Standard methods for
examination of water and wastewater”. It was observed that pH & temperature values at outlet by both the
processes are almost same. Reading were taking on two consecutive days and value of Biochemical Oxygen
Demand by UASB process was 32, 32mg/l and by SBR process was 11, 16mg/l. Chemical oxygen Demand by
UASB process was 112, 96mg/l and by SBR process was 32, 34mg/l. Total Suspended Solids by UASB process
was 58, 44mg/l and by SBR process was 10, 12mg/l. Both the processes were used for treating the wastewater
and the SBR process showed better results as comparative to UASB.
Reed bed technology uses shallow beds planted with reeds to treat wastewater through natural processes. There are two main types of reed beds - horizontal flow beds where wastewater flows horizontally through the reed root zone, and vertical flow beds where wastewater is delivered to the top of the bed in batches and drains vertically. Reed beds rely on the reeds and microbial activity in the bed's gravel layers to break down pollutants in wastewater over a detention period of 5-7 days. Factors like temperature, pollutant concentration, and oxygen levels influence the purification process. Reed beds provide a low-cost, sustainable option for treating various types of wastewater with minimal maintenance requirements.
The document describes the activated sludge process, which is the most common suspended growth process for municipal wastewater treatment. The process involves introducing air or oxygen into a mixture of wastewater and microorganisms to develop biological flocs that reduce organic content. Wastewater and microbes form mixed liquor that undergoes aeration and settling, with clarified effluent discharged and excess sludge wasted or returned. Common activated sludge process types include plug flow, complete mix, contact stabilization, and extended aeration. Design considerations include wastewater characteristics, effluent quality goals, and sludge production.
WASTE WATER TREATMENT BY AERATED LAGOONS , AN EFFECTIVE METHODOLOGY FOR WASTE WATER TREATMENT ALONG WITH ITS DESIGN FUNDAMENTALS AND WITH ADVANTAGES AND DISADVANTAGES .
This SlideShare is about Sewage Treatment Plants in Residential Complexes presented by Dr.Ananth S Kodavasal, Ecotech engineering in "Estate Manager Workshop-II" conducted by ApartmentADDA on 18th Nov 2010 in Bangalore.
It explains the below topics
• Wastewater Pollutants/Impact
• Physical, Chemical, Biological Unit Operations
• Types & Effects of Pollution
• Biological Treatment Variants
• Pros and Cons
At last the SlideShare details on the Important Acts and rules related to Environmental Protection.
Check the link below for details
http://apartmentadda.com/blog/water-workshop-for-apartments-report/
SEWAGE TREATMENT PLANT mini project reportNitesh Dubey
This document provides information about a research project analyzing the quality of treated sewage water from shipboard sewage treatment plants. Water samples were taken from 32 ships and analyzed for parameters like coliform bacteria, suspended solids, and biological oxygen demand. The results showed that none of the treated sewage water samples met standards in the MARPOL Annex IV regulations. The document also describes regulations for sewage discharge, potential health and environmental risks of untreated sewage, and common types of sewage treatment systems used on ships.
Characterization of microbial communities in water and biofilms along a large...Adi Levi
The document summarizes a study characterizing microbial communities along a large-scale seawater reverse osmosis (SWRO) desalination facility. The study found:
1) Microbial biofilm communities differed significantly between locations in the treatment process (rapid sand filtration, cartridge filters, reverse osmosis membranes).
2) Biofilms that developed on cartridge filters provided inocula that enhanced downstream biofouling on reverse osmosis membranes.
3) Prior to developing advanced antibiofouling treatments, site-specific characterization of microbial communities in feedwater, pretreatment systems, and on reverse osmosis membranes is required to optimize pretreatment and cleaning procedures and reduce costs.
The document discusses a case study on using a reverse osmosis (RO) membrane pilot plant to treat groundwater pollution. Two water samples with total dissolved solids (TDS) of 2,000 mg/L and 10,000 mg/L were treated in the RO plant. The plant achieved TDS rejections over 94% and permeate fluxes from 25.82 to 40.55 L/m2/hr. Results showed the potential of the RO plant to remove physical, chemical and microbiological contaminants like total coliform and E. coli in a single step of treatment. However, further operation of the plant over 100 hours or treating highly concentrated wastewater decreased treatment performance due to issues like membrane fou
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
This document summarizes key aspects of wastewater treatment processes and the role of the secondary settling tank. It discusses the main treatment steps - primary, secondary and tertiary treatment. The activated sludge process is described as the most common secondary treatment involving a biological tank and secondary settling tank. The secondary settling tank separates the treated wastewater from the microbial sludge mass and fulfills clarification, thickening and sludge storage functions. Different types of settling tanks are mentioned. Factors influencing sludge settling behavior such as particle size and concentration are also reviewed.
This document summarizes a presentation on flotation processes for wastewater treatment. It discusses how flotation works to separate solids from water by decreasing density. It also describes the components of a flotation system and challenges like rising sludge and bulking sludge. The author argues that using a high rate dissolved air flotation unit before sedimentation can help address these issues and improve effluent quality and plant efficiency compared to conventional activated sludge alone.
Biotechnology in Microbiology- includes the how microbial associations are worked out in secondary treatment techniques like activated sludge process, trickling filters, rotating biological contractors, composting, bioremediation etc.
Domestic Wastewater Treatment by Root Zone Technology Option: Colacassia PlantDr. Amarjeet Singh
Root Zone Technology is one of the low cost
methods to treat wastewater. With the help of this system we
can treat the Non-Point sources with best results. To achieve
this goal we have to divide the Non-Point sources into
constructed channels within the river bank followed by root
zone bed or if the Non-Point Sources is coming from natural
nallas we can provide this system within its Channel. We
have prepared channel on which I have developed the root
zone bed and have lab analysis of rector out put on number
of parameters. Flow rate and Detention time are the two
factors on which channels are to be designed. Therefore I
am changing the flow rate and finding out the change in
parameter with respect to detection time. The optimization
is when we get best result with maximum flow. I have got
satisfactory results for the detention time of Three day,
Seven day and twenty one day and Three day. With the help
of this data I have designed the root zone bed system for the
selected actual Domestic Sources.
Objectives :-
* Characterization and study of biochar.
*To examine biochar adsorption capacity.
*To determine the effect of KMnO4 as modifying agent on biochar adsorption.
1) Sewage treatment plants are necessary to purify wastewater before discharge into rivers or oceans. They employ natural biological processes to break down pollutants.
2) The typical sewage treatment process has four stages: primary treatment to remove solids; secondary biological treatment using microorganisms to oxidize compounds; secondary settling; and tertiary treatment if needed before discharge.
3) Common secondary treatment methods are biological filtration using media to support microbe growth, activated sludge using aeration to sustain microbes, and Pasveer Ditches which circulate and aerate sewage.
There is an intrinsic connection between biodiversity conservation, water and sanitation. With appropriate technologies, wastewater can be treated to produce fit-for-purpose water with recovery of nutrients to enhance biodiversity conservation in terms of flora and fauna. This project highlights a pilot subsurface flow Constructed Wetland unit in order to identify its performance in treating domestic wastewater and in recovering nutrients.
The project won the 1st Prize in National Quarry Life Award in 2012 in Tanzania.
Read more: http://www.quarrylifeaward.com/project/integrated-constructed-wetland-wastewater-treatment-rainwater-harvesting-nutrient-recovery
This document describes a study on treating synthetic wastewater using an activated sludge process in a laboratory-scale jet loop reactor. The researchers tested COD (chemical oxygen demand) removal efficiency at different mixed liquor volatile suspended solids (MLVSS) concentrations and a hydraulic retention time of 60 minutes. They found that over 95% COD removal could be achieved with an MLVSS of 3000 mg/L. Tables of results show COD levels decreasing over 5 hours as MLVSS increased from 1000 mg/L to 3000 mg/L. Graphs illustrate the relationships between time and COD or MLVSS. The reactor demonstrated high wastewater treatment efficiency under the conditions tested.
This document is the preface and table of contents for the Advanced Activated Sludge Study Guide published by the Wisconsin Department of Natural Resources in December 2010. It provides an overview of the guide and outlines its contents, which include chapters on theory and principles, operation and maintenance, monitoring and process control, safety and regulations, and calculations relevant to advanced activated sludge processes. It acknowledges the workgroup that developed the study guide objectives and exam questions.
biological treatment i activated sludge processManish Goyal
The activated sludge process uses microorganisms to biologically treat wastewater. Wastewater enters an aeration tank where microbes consume organic matter, producing new cells and reducing biochemical oxygen demand. Mixed liquor flows to a clarifier where microbes are separated from treated water; some microbes are recycled to the aeration tank while excess sludge is wasted. The process reduces organic matter through microbial growth and substrate utilization under aerobic conditions.
The document presents a model for trickling filter process design. It describes Eckenfelder's pseudo-first-order reaction performance equation for substrate removal rate. The equation relates substrate concentration over time to rate constant, substrate concentration, and contact time. Contact time depends on filter depth and surface loading rate. The model is used to design a trickling filter with a given influent BOD, required effluent BOD, flow rate, filter depth, and removal rate constant to achieve the surface loading rate needed.
Wastewater treatment by vermi filtration technologyvivatechijri
Vermifiltration units are sludge-free, noise-free and low- or no-electricity-requiring systems of
operation. The aim of this study was to emphasize wastewater treatment by vermifiltration technology using
waste-eater earthworms to highlight the benefits of clean and nutritive vermifiltered water (vermiaqua) uses in
agriculture to the farmers. They work on natural capacity of earthworms to treat wastewater from different
sources. In view of rising concern about pollution of water bodies due to discharge of waste in them, it is
necessary to initiate alternative thinking as conventional methods through STPs (Sewage treatment Plants) have
had limited success. In recent years the application of specifically designed filtration based technology
(popularly known as Vermifiltration technology) for treatment of wastewater municipal, urban and agricultural,
is becoming widely acceptable. It treats the wastewater in natural manner without the use of chemicals. In
short, Vermifiltration technology is an improved filtration system for treatment of wastewater. The main
objective of present research work is to provide and popularize a simple, feasible, practically sound, ecofriendly and cost effective technology for wastewater treatment. Vermifiltration technology is such a type of
system, which reduces the impact of sewage and converts into useful water for gardening and irrigation
purpose.
Recycling waste through constructed wetlandBineet Chhajer
The document summarizes a 3-day training program on technologies for waste recycling and sustainable development, including water sensitive plumbing and constructed wetlands. It discusses contemporary issues like limited water resources, increasing waste generation and air pollution in cities. It provides examples of constructed wetland projects in Barcelona, Pune, Delhi, Agra, and Kolkata that treat wastewater and restore the environment. Water sensitive techniques like low-flow toilets and showers, sensor taps, and aerated flow restrictors are presented as ways to reduce residential water usage. The training emphasizes decentralizing waste management through neighborhood-level solutions and integrating ecology and landscape.
“Study The Different Parameters of Sewage Treatment With UASB & SBR Technolog...IOSR Journals
Abstract: Every community produces both liquid and solid wastes and air emissions. The liquid wastewastewater-is
essentially the water supply of the community after it has been used in a variety of applications.
From the standpoint of sources of generation, wastewater may be defined as a combination of the liquid or
water-carried wastes removed from residences, institutions, commercial and industrial establishments, together
with such groundwater, surfacewater and stromwater as may be present. This waste water through sewer comes
to the sewage treatment plant so that parameters are reduced and treated wastewater be disposed into water or
land. For treating the sewage UASB( UP FLOW ANAEROBIC SLUDGE BLANKET) and SBR(SEQUENCING
BATCH REACTOR) technologies are mostly used.
All the parameters of these samples were analyzed using standard methods prescribed in “Standard methods for
examination of water and wastewater”. It was observed that pH & temperature values at outlet by both the
processes are almost same. Reading were taking on two consecutive days and value of Biochemical Oxygen
Demand by UASB process was 32, 32mg/l and by SBR process was 11, 16mg/l. Chemical oxygen Demand by
UASB process was 112, 96mg/l and by SBR process was 32, 34mg/l. Total Suspended Solids by UASB process
was 58, 44mg/l and by SBR process was 10, 12mg/l. Both the processes were used for treating the wastewater
and the SBR process showed better results as comparative to UASB.
Reed bed technology uses shallow beds planted with reeds to treat wastewater through natural processes. There are two main types of reed beds - horizontal flow beds where wastewater flows horizontally through the reed root zone, and vertical flow beds where wastewater is delivered to the top of the bed in batches and drains vertically. Reed beds rely on the reeds and microbial activity in the bed's gravel layers to break down pollutants in wastewater over a detention period of 5-7 days. Factors like temperature, pollutant concentration, and oxygen levels influence the purification process. Reed beds provide a low-cost, sustainable option for treating various types of wastewater with minimal maintenance requirements.
The document describes the activated sludge process, which is the most common suspended growth process for municipal wastewater treatment. The process involves introducing air or oxygen into a mixture of wastewater and microorganisms to develop biological flocs that reduce organic content. Wastewater and microbes form mixed liquor that undergoes aeration and settling, with clarified effluent discharged and excess sludge wasted or returned. Common activated sludge process types include plug flow, complete mix, contact stabilization, and extended aeration. Design considerations include wastewater characteristics, effluent quality goals, and sludge production.
WASTE WATER TREATMENT BY AERATED LAGOONS , AN EFFECTIVE METHODOLOGY FOR WASTE WATER TREATMENT ALONG WITH ITS DESIGN FUNDAMENTALS AND WITH ADVANTAGES AND DISADVANTAGES .
This SlideShare is about Sewage Treatment Plants in Residential Complexes presented by Dr.Ananth S Kodavasal, Ecotech engineering in "Estate Manager Workshop-II" conducted by ApartmentADDA on 18th Nov 2010 in Bangalore.
It explains the below topics
• Wastewater Pollutants/Impact
• Physical, Chemical, Biological Unit Operations
• Types & Effects of Pollution
• Biological Treatment Variants
• Pros and Cons
At last the SlideShare details on the Important Acts and rules related to Environmental Protection.
Check the link below for details
http://apartmentadda.com/blog/water-workshop-for-apartments-report/
SEWAGE TREATMENT PLANT mini project reportNitesh Dubey
This document provides information about a research project analyzing the quality of treated sewage water from shipboard sewage treatment plants. Water samples were taken from 32 ships and analyzed for parameters like coliform bacteria, suspended solids, and biological oxygen demand. The results showed that none of the treated sewage water samples met standards in the MARPOL Annex IV regulations. The document also describes regulations for sewage discharge, potential health and environmental risks of untreated sewage, and common types of sewage treatment systems used on ships.
Characterization of microbial communities in water and biofilms along a large...Adi Levi
The document summarizes a study characterizing microbial communities along a large-scale seawater reverse osmosis (SWRO) desalination facility. The study found:
1) Microbial biofilm communities differed significantly between locations in the treatment process (rapid sand filtration, cartridge filters, reverse osmosis membranes).
2) Biofilms that developed on cartridge filters provided inocula that enhanced downstream biofouling on reverse osmosis membranes.
3) Prior to developing advanced antibiofouling treatments, site-specific characterization of microbial communities in feedwater, pretreatment systems, and on reverse osmosis membranes is required to optimize pretreatment and cleaning procedures and reduce costs.
The document discusses a case study on using a reverse osmosis (RO) membrane pilot plant to treat groundwater pollution. Two water samples with total dissolved solids (TDS) of 2,000 mg/L and 10,000 mg/L were treated in the RO plant. The plant achieved TDS rejections over 94% and permeate fluxes from 25.82 to 40.55 L/m2/hr. Results showed the potential of the RO plant to remove physical, chemical and microbiological contaminants like total coliform and E. coli in a single step of treatment. However, further operation of the plant over 100 hours or treating highly concentrated wastewater decreased treatment performance due to issues like membrane fou
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
This document summarizes key aspects of wastewater treatment processes and the role of the secondary settling tank. It discusses the main treatment steps - primary, secondary and tertiary treatment. The activated sludge process is described as the most common secondary treatment involving a biological tank and secondary settling tank. The secondary settling tank separates the treated wastewater from the microbial sludge mass and fulfills clarification, thickening and sludge storage functions. Different types of settling tanks are mentioned. Factors influencing sludge settling behavior such as particle size and concentration are also reviewed.
This document summarizes a presentation on flotation processes for wastewater treatment. It discusses how flotation works to separate solids from water by decreasing density. It also describes the components of a flotation system and challenges like rising sludge and bulking sludge. The author argues that using a high rate dissolved air flotation unit before sedimentation can help address these issues and improve effluent quality and plant efficiency compared to conventional activated sludge alone.
Biotechnology in Microbiology- includes the how microbial associations are worked out in secondary treatment techniques like activated sludge process, trickling filters, rotating biological contractors, composting, bioremediation etc.
Biological and Advanced Water Treatment.pptxYalelet Abera
Micro-organisms play an essential role in the biological treatment of wastewater by converting organic waste into more stable substances. There are three main types of biological wastewater treatment processes - aerobic, anaerobic, and anoxic. Two common biological wastewater treatment methods are trickling filters and activated sludge processes. Trickling filters use microorganisms attached to media to treat wastewater as it trickles down. Activated sludge processes use air and microorganisms in suspension to treat wastewater in aeration tanks, with the treated wastewater then sent to secondary clarifiers. Design considerations for biological wastewater treatment systems include organic loading rates, hydraulic loading rates, and detention
Conventional wastewater treatment involves primary, secondary, and sometimes tertiary treatment stages. Primary treatment uses settling tanks to remove solids. Secondary treatment uses microbes and oxygen to break down remaining organic matter. This usually involves an aeration tank and secondary clarifier. Tertiary treatment may further remove nutrients or other contaminants through methods like filtration, carbon adsorption, or phosphorus/nitrogen removal. Sludge from primary and secondary clarifiers undergoes anaerobic digestion to reduce pathogens and volume before disposal or reuse.
This document provides an overview of biological treatments of water. It begins with an abstract describing biological treatment systems that use microorganisms to break down organic materials. It then discusses water treatment processes generally before focusing on biological methods. The key biological methods described are aerobic treatment which uses oxygen and aerobic microorganisms, and anaerobic treatment which does not use oxygen and relies on anaerobic microorganisms. Specific biological treatment technologies summarized include conventional activated sludge processes, cyclic activated sludge systems, trickling filters, and phytoremediation. The document emphasizes that both aerobic and anaerobic biological methods are often used together to effectively treat wastewater.
The objective of secondary treatment is the further treatment of the effluent from primary treatment to remove the residual organics and suspended solids.
Aerobic biological treatment is performed in the presence of oxygen by aerobic microorganisms (principally bacteria) that metabolize the organic matter in the wastewater, thereby producing more microorganisms and inorganic end-products , as
CO2
NH3
H2O etc.
Primary and secondary wastewater treatment..snehalmenon92
This document provides an overview of primary and secondary wastewater treatment processes. It begins by defining wastewater treatment as applying technology to improve water quality. Primary treatment involves removing coarse solids and grit, while secondary treatment uses biological processes like activated sludge to further break down organic matter. The document then describes various primary and secondary treatment units and processes in detail, such as grit chambers, primary clarifiers, trickling filters, and biological nutrient removal. It concludes by discussing tertiary/advanced treatment options for removing additional contaminants.
This document provides an overview of a turnkey solution for water and wastewater treatment. It discusses various treatment processes including bioaugmentation, screens, primary clarification, biological processes, and sedimentation tanks. It then focuses on the activated sludge process for secondary treatment, describing the basic process, design considerations like organic loading and aeration requirements, and different aeration methods like diffused, spray, turbine, and surface aeration.
Sewage is comprised of about 99.9% water and 0.1% solid or dissolved wastes from households, industries, and stormwater runoff. Sewage undergoes physical, chemical, and biological treatment processes to remove contaminants and produce treated wastewater safe for release. Pretreatment screens and filters remove large solid objects, while primary treatment uses sedimentation to remove about half the total solids. Secondary treatment further breaks down organic matter using trickling filters, activated sludge systems, filter beds, or rotating biological contactors. Membrane bioreactors can also be used for secondary treatment and achieve higher removal rates than conventional activated sludge. The byproduct of sewage treatment is sewage sludge
Constructed wetlands are a low-cost option for wastewater treatment that uses natural processes to remove pollutants. There are three main types: surface flow wetlands with exposed water, and horizontal and vertical subsurface flow wetlands where water flows below ground. Wetlands are effective at removing organic matter, solids, nutrients, and pathogens through sedimentation, filtration, microbial action, and plant uptake. They provide benefits like wildlife habitat and require little energy or maintenance compared to mechanical treatment systems. Literature shows that wetlands can achieve high removal rates of 70% or more for BOD, TSS, and bacteria while lowering costs and nutrients for water reuse.
Low Cost Anaerobic Treatment of Municipal Solid Waste Leachateiosrjce
IOSR Journal of Environmental Science, Toxicology and Food Technology (IOSR-JESTFT) multidisciplinary peer-reviewed Journal with reputable academics and experts as board member. IOSR-JESTFT is designed for the prompt publication of peer-reviewed articles in all areas of subject. The journal articles will be accessed freely online
The Up-flow Anaerobic Sludge Blanket (UASB) reactor is a form of anaerobic digester used for wastewater treatment. It uses an anaerobic process to form a blanket of granular sludge suspended in the reactor tank. Wastewater flows upwards through the blanket where anaerobic microorganisms degrade the organic pollutants. Over time, the microorganisms form dense granules that efficiently remove biochemical oxygen demand, chemical oxygen demand, and total suspended solids from the wastewater. The UASB reactor also produces biogas containing methane, which can be captured and used as an energy source.
This document summarizes the three stages of sewage treatment - primary, secondary, and tertiary. It describes the processes that occur at each stage. Primary treatment involves settling and removal of solids. Secondary treatment uses microorganisms to remove dissolved and suspended biological matter. Tertiary treatment provides additional treatment to allow wastewater discharge into sensitive ecosystems. The document also provides details about various pretreatment processes like screening, grit removal, and flow equalization that occur before primary treatment.
An Overview of Aquaponic Systems: Hydroponic
Components
D. Allen Pattillo
Iowa State University, pattillo@iastate.edu
http://lib.dr.iastate.edu/ncrac_techbulletins/19/
This document provides an overview of reverse osmosis technology. It discusses how reverse osmosis was first used commercially in 1970 by Texas Instruments to treat water for electronics manufacturing. It then summarizes growth in global reverse osmosis capacity from 880,000 gallons per day in 1970 to over 500 million gallons per day in 1984. The document also reviews key applications of reverse osmosis including industrial, municipal, power, and military uses.
This document discusses the history and applications of reverse osmosis technology. It notes that:
- The first large industrial reverse osmosis system was installed in 1970 at a Texas Instruments plant, where it increased manufacturing yields enough to pay for itself in two weeks.
- By the end of 1984, global reverse osmosis operating capacity was 524 million gallons per day, with the largest uses being municipal water supplies (38%), industrial process water (31.5%), and power plant water (11%).
- Reverse osmosis transforms unusable water into a usable resource by applying pressure greater than the osmotic pressure to force water molecules through a semi-permeable membrane, leaving dissolved ions behind.
The document discusses wastewater treatment processes. It describes that wastewater contains a variety of pollutants from physical to biological contaminants. The size of treatment systems depends on sewage volume and anticipated flows. Common treatment methods include primary, secondary, and tertiary levels. Primary treatment involves screens, comminution, grit removal and sedimentation to remove solids. Secondary treatment uses biological processes like trickling filters, activated sludge, and oxidation ponds to further reduce organic matter. Tertiary treatment can achieve very high removal rates of 99% for drinking water quality effluent.
The document discusses various aspects of the suspended growth bio-treatment process known as the activated sludge process. It describes the process as using microorganisms to consume organic contaminants in wastewater. The activated sludge process is an economical biological wastewater treatment method that can produce high quality effluent. It also discusses different design configurations for activated sludge systems including extended aeration, sequencing batch reactors, and oxidation ditches. BOD removal and nitrification are key functions of the activated sludge process.
Wastewater Management with Anaerobic Digestion Accra, GhanaHeather Troutman
This analysis identified Old Fadama, an informal settlement of 80,000 inhabitants in Accra, Ghana, that currently lacks adequate access to sanitation facilities, clean water, electricity, and is burdened by severe environmental degradation as a possible site to implement a system of small-scale anaerobic digesters throughout the community as a means to treat 122,139 L of wastewater per day producing 20,727 to 29,406 m3 biogas per day, which is sufficient to run a cooking stove for 3.24 to 4.59 hours per house per day (assuming 5 inhabitants per house). Additionally, this system can provide sufficient fertilizer and soil amendment for utilization in urban and peri-urban agriculture, which provides livelihood for 18 percent of Accra’s total population and produces 90 percent of all perishable produce consumed in the city.
This document describes various municipal wastewater treatment processes including primary treatment to remove settleable solids, secondary treatment using biological processes like trickling filters and activated sludge to reduce BOD, and tertiary treatment using oxidation ponds. It provides details on screening, grit removal, sedimentation, trickling filters, activated sludge, and aerobic, anaerobic and facultative ponds. Diagrams and videos are referenced to illustrate key processes. The goal of wastewater treatment is to extract pollutants, remove toxins, neutralize particles, kill pathogens, and reduce BOD, COD and eutrophication.
Literature Review Basics and Understanding Reference Management.pptxDr Ramhari Poudyal
Three-day training on academic research focuses on analytical tools at United Technical College, supported by the University Grant Commission, Nepal. 24-26 May 2024
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
The presentation also covers the positive and negative aspects of inductive bias, along with strategies for mitigating potential drawbacks. We'll explore examples of how bias manifests in algorithms like neural networks and decision trees.
By understanding inductive bias, you can gain valuable insights into how machine learning models work and make informed decisions when building and deploying them.
We have compiled the most important slides from each speaker's presentation. This year’s compilation, available for free, captures the key insights and contributions shared during the DfMAy 2024 conference.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
RAT: Retrieval Augmented Thoughts Elicit Context-Aware Reasoning in Long-Hori...
US 3904525
1. United States Patent (19) (11 3,904,525
Rosenberg (45) Sept. 9, 1975
(54) WASTE TREATMENT APPARATUS 57 ABSTRACT
76) Inventor: Lawrence R. Rosenberg, 1 Chelsea This patent discloses waste treatment apparatus in
Ridge Dr., Wappingers Falls, N.Y. which after primary treatment of waste (liquid waste)
12590 aeration of the waste occurs in the equalization tank
(22 Filed: Aug. 23, 1973 to start the process to change the normally anerobic
21 ) Appl. No.: 390,892
52) U.S. Cl.................................... 210/150; 261/92
5 i Int. Cl........................................... B01D 33/28
(58) Field of Search....... 210/15, 17, 150, 151, 170,
210/195, 218-221; 261/92, DIG. 75
56) References Cited
UNITED STATES PATENTS
2,591,497 4f1952 Berl................................ 210/150 X
3,269,542 8/1966. Renzi et al...... ... 21Of 17 X
3,371,033 2/1968 Simmons et al. ... ..., 21Of 17 X
3,528,549 9/1970 Ray..................... ... 210/151
3,618,778 11/1971 Benton et al....... ... 2)Of150
3,660,277 5f1972 McWhirter et al. ... 210/15 X
3,680,704 8, 1972 Schaefer ............. ... 2. Of17O X
3,681,236 8/1972 Bergles ct al... ... 20/195 X
3,777,891 12/1973 Stengclin ............................ 210/150
3,788,478 1/1974 Savage ......... ... 210/221 X
3,789,986 2/1974 Oldham et al.. ... 210/151 X
3,827,559 8/1974 Gass ct al. .......................... 210/150
Primary Examiner-Samih N. Zaharna
Assistant Examiner-Robert H. Spitzer
Attorney, Agent, or Firm-William J. Dick
waste material to at least a partially aerobic state.
Thereafter the waste material is applied by a spray to
at least the first stages of a rotating disk biological re
actor where biological slimes are grown on the rotat
ing disks, which slimes serve to further the process of
removing pollutants from the waste being supplied
thereto. The reactor section is comprised ofa plurality
ofdisks each made up ofgroups ofthin wedge shaped
elements of at least a pair of sets, each element of a
set cooperating with each other element in tightly
packed relation for ease ofshipping while when mated
with the elements of the other set are spaced apart,
and when connected together about the rotating shaft
ofthe reactor form spaced apart disks upon which the
biological slime may form.
The purpose of this abstract is to enable the public
and the Patent Office to determine rapidly the subject
matter of the technical disclosure of the application.
This abstract is neither intended to define the
invention of the application nor is it intended to be
limiting as to the scope thereof.
Claims, 16 Drawing Figures
2. 3,904,525PATENTEDSEP 91975
SEET 1. Of 8
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II
NYSOESOENS,N,N,No..
10. 3,904,525
WWASTE TREATMENT APPARATUS
SUVMARY, OF THE INVENTION AND STATE OF
THE PRIOR ART
The present invention relates to apparatus for waste
treatment, and more particularly relates to improve
ments in biological reactors, pre-effluent aeration and
supply of effluent to the reactor.
Because ofthe increased concern by thegeneral pop
ulation and thus of Government regulatory agencies,
water purification has become one ofthe primary con
cerns of the ecologists. Obviously population shifts as
well as industrial expansion has created a problem by
a constant increase in the level of pollution of lakes,
rivers and streams. To reverse the trend of increased
pollution ofsuch bodies of water it has become neces
sary to increase the size and efficiency ofexistingwaste
treatment facilities while improving on new plants with
out an overt increase in the cost of construction of new
plants.
By way ofbackground there are three basic processes
presently in use for waste treatment. The most widely
recognized of the three processes is that of primary
waste treatment in which sedimentation occurs to ef
fect the removal ofthe solids which may settle from the
waste water. Ofcourse, chemical coagulants are some
times used to increase the efficiency of the process in
which case the primary treatment may remove up to
50% of the carbonaceous pollutants when such pollut
ants may be expressed by bio-chemical oxygen demand
(hereinafter referred to as B.O.D.)
The second process utilized for the treatment of
waste water in normally termed a secondary treatment
process which is accomplished conventionally by pro
vidingapparatus which permits the growth ofbiological
slimes (sometimes called biomasses) orflocs which ulti
lize the pollutants in the waste media to enhance their
natural growth processes. In the secondary treatment
process, the waste water is brought into contact with
the biological slimes to supply nutrients and oxygen to
the micro organisms, the slimes then being separated
from the waste water to effect the necessary purifica
tion or clarification of the waste media. Thus in this
type of secondary treatment process, it is necessary
that the biological slime be provided with a continuous
supply of nutrients so as to maintain the growth ofthe
micro organisms as well as requiring a continued oxy
gen supply to effect the nutrition process.
The second process of secondary treatment of waste
water which has gained wide acceptance is known as
the activated sludge process which providesforthe aer
ation ofthe waste water in the presence ofa controlled
amount offree floating biological flocs. The microor
ganisms in the biological flocs extract the pollutants
from the waste water, thereby deriving their nutrition,
and are supplied with oxygen by diffused air which is
injected below the surface of the aeration tank. Thus
pollutants may be removed from the waste material by
conversion into biological slimes which feed, in a con
tinuous cycle, upon the nutrients of the waste along
with appropriate oxygenation. While this process can
remove approximately 60% of the carbonaceous
B.O.D., employing certain variations in aeration, such
as modified aeration and step aeration, up to 90% of
the carbonaceous B.O.D. as well as oxidation ofammo
nia nitrogen may occur.
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The third basic process for treating waste water is
commonly referred to as the standard rate or high rate
trickling filtration process. In this type of process, set
tled waste media is passed over biological slimes grown
on and attached to stationary surfaces. Purification or
clarification of the waste media occurs in a manner
similar to the activated sludge process in that organic
pollutants in the waste water are converted into biolog
ical slimes that are subsequently separated from the
clarified media. Plants employing such a process nor
mally effect a removal of between 60 and 90% of the
carbonaceous B.O.D. depending upon the flow rate
and the load presented to the filtration media.
In recent years a fourth process has come into vogue,
this process being generally referred to as a rotating
disk process for secondary biological waste media
treatment. The process evolved from basic work and
research that was conducted in Germany in the mid
50's. Due to its inherent advantages, which will be dis
cussed more fully hereinafter, there are numerous such
installations existing today in western Europe. In the
mid 60's the process was introduced into the United
States. In this secondary biological waste water treat
ment process, large diameter plastic media or disks are
mounted on a horizontally disposed shaft and rotated
slowly in a tank with 40 to 50% of the surface area of
the disks being submerged in the waste media at any
one time. Organisms which are present in the waste
water adhere to the rotating disks and multiply, form
ing a biological mass on the surface of the rotating
disks. As the disks rotate, the water in the tank moves
down the disk, absorbing oxygen from the surrounding
air. The organisms not only remove oxygen from the air
butalso remove both dissolved oxygen and organic ma
terials from the film of water as it moves down the ro
tating disk. The normal stress of the biological mass
and the shearing forces due to the weight of the mass
as it passes through the waste media causes any excess
biological mass to drop from the disk into the waste
media. In this manner clogging of the disks is pre
vented, while a constant biological mass of micro or
ganisms is kept in the media. Additionally, the rotating
disks create a mixing action which maintains the solids
in suspension until the treated waste water carries the
waste, including the solids, out of the tank for separa
tion and disposal. The advantages of the rotating bio
logical disks are many: (1) the surface area ofthe disks
is far greater than the surface area ofthe waste media
in the tank, permitting the development ofa large area
of fixed biological culture; (2) the movement of the
disks through the media provides vigorous contact of
the biological mass with the waste media providing eff
cient aeration of the waste media; (3) the rotation of
the reactor provides for agitation of the media.
However, there are some disadvantages to the exist
ing apparatus utilized for rotating biological reactors.
For example, in large plants where the disks are of
great diameter there is difficulty in shipping the disks
O from their point of manufacture to the point of assem
65
bly, requiringspecial packing,special carriers resulting
in increased costs of plant construction. Additionally,
due to the very large diameter of the disks anywhere
from 12 to 24 feet in diameter and even more, molds
forformation ofthe disks are extremely expensive rais
ing the cost ofmanufacture. Also, because of the way
Some systems are presently employed, the waste water
iscomposedalmostentirely ofananaerobicpopulation
11. 3.
which requires excessively large biological reactors to
effectively provide secondary treatment to the waste
media.
In view of the above, it is a principal object of the
present invention to provide an improved rotating bio
logical reactor which is easier to assemble in the field.
Another object ofthe present invention is to provide
an improved biological reactor disk in which the disk
is composed ofa plurality ofindividual elements to fa
cilitate construction in the field as well as ease ofship
ping. -
Yet another object of the present invention is to pro
vide an improved disk for a biological reactor in which
the individual disks are formed of a plurality of ele
ments, each element of adjacent disks being adapted
for cooperation with the elements of disks on opposite
sides thereof so as to permit ease of alignment of the
disks and proper spacing thereof from disk to disk.
Yet another object ofthe present invention is to pro
vide elements of a disk ofa rotating biological reactor
in which the elements of some of the disks may be
packed in nested relation one with regard to the other
for ease of shipment, and which may be more easily
handled in the field when mating with elements of an
other set.
Still another object ofthe present invention is to pro
vide means for at least starting the aerobic process by
supplying oxygen to the media in the equalization tank
so as to reduce the loading effect on the first stages of
the biological reactor.
Yet another object ofthe presentinvention is to pro
vide the novel manner of moving the media onto the
initial stages of the biological reactor so as to increase
the effective area ofthe initial stages ofthe reactor, and
to prevent inadvertent biomass removal from the initial
stages during periods of high media throughput.
Other objects and a more complete understanding of
the invention may be had by referring to the following
specification and claims taken in conjunction with the
accompanying drawings in which: -
FIG. is a fragmentary sectional view ofprimary and
secondary treatment apparatus constructed in accor
dance with the present invention;
FIG. 2 is an enlarged fragmentary sectional view
taken along line 2-2 of FIG. ;
FIG. 3 is an enlarged fragmentary sectional view
taken along line 3-3 of FIG. 1;
FIG. 3A isan enlarged fragmentary view ofa portion
of the apparatus illustrated in FIG. 3;
FIG. 4 is a fragmentary sectional side elevational
view of a portion of the apparatus illustrated in FIGS.
1-3;
FIG. 5 is a fragmentary sectional view taken along
line 5-5 of FIG. 4;
FIG. 6 is a perspective view ofa plurality ofelements
comprising a group adapted for coupling to the appara
tus best illustrated in FIGS. 3 and 4:
FIG. 6A is an enlarged fragmentary perspective view
taken along line 6A-6A of FIG. 6;
FIG. 6B is an enlarged fragmentary sectional view
taken along line 6B-6B of FIG. 6;
FIG. 7 is an enlarged fragmentary sectional view
through a plurality of the elements illustrated in FIG.
6 to show their relationship one to the other;
FIG. 8 is a fragmentary sectional view illustrating
some of the elements illustrated in FIG. 6 positioned
for shipmentfrom a manufacturingsource to ajob site;
3,904,525
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FIG. 9 isa fragmentary sectional view, similar to FIG.
7 but showing another embodiment of elements con
structed in accordance with the present invention;
FIG. 10 is a fragmentary sectional view, similar to
FIG.8 but showing some of the elements illustrated in
FIG. 9 in nested relation for shipment from a manufac
turing source; -
FIG. 1 is a fragmentary plan view of another em
bodiment showing alternate means to hold groups of
elements in the apparatus illustrated in FIGS. 1-4;
FIG. 12 is an enlarged fragmentary view ofa portion
of the apparatus illustrated in FIG. 11; and
FIG. 13 is a fragmentary sectional view taken along
line 13-13 of FIG. 12.
Referring now to the drawing, and especially FIG. 1
thereof, a primary and partial view of a secondary
treatment apparatus 10 and 50 respectively is illus
trated therein. In the illustrated instance the primary
treatment apparatus comprises the well known septic
tank, which includes a first compartment 11 which is .
joined to a second compartment 12, the compartments
being divided by an upstanding wall 3 having a port
13A therein at the approximate midpoint of the wall.
The first compartment 11 includes a waste or raw sew
age inletpipe 14which supplies raw sewage to the first
compartment 11 ofthe septic tank. As is conventional,
the septic tank acts as a settling tank, the sludge or
heavier material 15 falling to the bottom ofthe tank or
first compartment 11, while the lighter grease or scum
moves up the liquid waste and floats along the upper
surface thereof as at 16. At the central portion of the
first compartment the waste waterisclearerthan either
the upperor lowerportion,and thusthe clarified waste
water moves through port 3A into the second com
partment 12 wherein additional clarification occurs,
sludge 15 also settling into the bottom in compartment
12 while scum and grease float on the surface of the
upper portion. In the second compartment, once again
therefore, the central portion ofthe waste media forms
a clarified zone. Accordingly, the flow of waste media
is normally taken from this clarified zone and moved
therefrom into further processing apparatus.
Asshown in FIG. 1,an outlet pipe 17 extends into the
clarified zone and hasan outlet port 18 which projects
through an upstanding wall 19 separating the second
compartment from an equalization, sometimes called
an antisurge tank 20. The equalization or antisurge
tank 20functionsto equalize the dailyflow and thereby
even outtheflow to the secondary treatmentapparatus
S. . . .
Conventionally the waste material entering from the
Septic tank or primary treatment apparatus into the
equalization tank 20isanaerobic with regard toits con
tent of oxygen. (Anaerobic means “devoid of oxy
gen'.) Thus the waste matter thatis in the equalization
tank is anaerobic and at the same time full of organic
matter because the bacteria has consumed all of the
available oxygen. Conventionally, the anaerobic waste
material isthen applied to a secondary treatmentappa
ratus wherein oxygen is supplied to allow bacteria
growth to consume the organic matter in the waste me
dia, thereby removing the waste material.
In accordance with a feature ofthe invention, means
are provided in the equalization tank to start the pro
cess ofchangingthe normallyanaerobic waste material
to at least make the waste media partially aerobic. To
this end, and as best illustrated in FIGS. 1 and 2, the
12. 3,904,525
S
equalization tank 20 isprovided with at leastone, in the
illustrated instance a pair of dosing pumps 21, the
pumps beingdesignated 21A and 2 B (FIG. 2) for pur
poses of identification, which feed the waste media in
the equalization tank through discharge piping 22,
(22A and 22B) to the secondary treatment apparatus
50. Each of the discharge piping includes a metering
valve 23, (23A and 23B) to meter the flow from the
equalization tank to the secondary treatment appara
tuS.
In accordance with this feature of the invention,
means are provided to supply oxygen to the waste
media in the equalization tank. To this end, on the inlet
side of the metering valves 23A, 23B is a recirculating
or feedback line or pipe 24 which supplies a recirculat
ing stream of waste media to an aerator, in the illus
trated instance a venturi type nozzle discharge pump
25, and designated 25A and 25B in FIG. 2. The aerator
or venturi pump 25 has an air inlet pipe 26 which ex
tends vertically in the equalization tank and is con
nected to the atmosphere or a source ofairso as to per
mit, as the pump 25 operates, the drawing into and dis
charge from the pump of oxygen containing air. Al
though not shown, the air inlet piping of each venturi
pump (25A, 25B) may be joined to the air inlet piping
of the other to form a common air intake or the intakes
may be separate.
Inasmuch as the oxygen supplied by the aerating or
venturi pump 25 to the waste media in the equalization
tank tends to move upwardly through the waste, the
discharge being preferably near or adjacent the bottom
of the equalization tank, an air space or pocket will
form at the upper portion ofthe tank which may, ifde
sired, by recycled through the aerator and the tank by
providing a vent 27 at the top of the tank, which vent
is connected to an ozone generator 28, such as the
ozone generator sold by C. E. Bauer Company of
Springfield, Ohio. In this embodiment, the apparatus
28 may also have an intake 26A from the atmosphere
through it so that a constant charge of fresh air is sup
plied to the aerating or venturi pump 25.
Thus even with the metering valves 23 closed down,
a constantdischarge ofwaste media through the piping
or recirculating line 24 occurs and thus the pump 25
effects preliminary aeration of the waste media in the
equalization tank starting the process of injecting dis
solved oxygen into the waste media and permitting the
initial formation of some oxygen requiring bacteria to
commence the process of removing nutrients (organic
material) from the waste media. Additionally, even this
preliminary head start on formation of or changing of
the waste media in the equalization tank to at least a
partiallyaerobic nature willgive a headstartto the sec
ondary treatment apparatus permitting an overall re
duction in the size of the secondary treatment appara
tus for given flow conditions.
Under normal operating conditions only one of the
dosing pumps 21 is conventionally used to discharge
waste media from the equalization tank 20 into the sec
ondary treatmentapparatus50. However, itis normally
required that there be a standby dosing pump so that
in the event ofbreakdown ofone ofthe pumps, the sys
tem will not have to be shut down when one pump is
out of operation and being repaired. Accordingly, and
as bestshown in FIG.2, the metering valves23 are con
ventionally connected through piping 30A and 30B to
a tee 31 which discharges the waste media through line
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32 to the inlet ofthe secondary treatment apparatus 50.
In conventional plants the piping 32 discharges di
rectly into the first compartment of the secondary
treatment apparatus 50 which under normal loading
conditions issatisfactory. However, and as will be more
fully explained hereinafter, under conditions of severe
loading, that is when waste media flow is at a very high
rate, thatis the metering valves 23 are wide open, many
times the hydraulic agitation effects a removal of the
biological slime (biomass) from the initial stages ofthe
rotating biological reactor. This cuts down the effi
ciency of the secondary treatment apparatus and can
result in degradation of the entire system because of
the removal of the nutrient consuming bacteria from
the initial stages ofthe reactor. Accordingly, and in ac
cordance with one feature of the invention, extending
the inlet piping32 in opposite directions along the inlet
ofthe tank 51 ofthe biological reactor and by provid
ing a plurality of apertures 33 in the piping 34A and
34Bthus extended the media may be sprayed out ofthe
piping along the entire width of the tank 51 inhibiting
severe hydraulic agitation, even under high flow condi
tions. Preferably the apertures 33A are directed down
wardly so that the media entry is into the tank as op
posed to being against the first stages ofthe reactor. In
this connection the apertured single pipe could be a
plurality of inlet pipes.
Because of the increased flow which is possible due
to pre-aeration, and in the event that it is desirable to
operate both dosing pumps 21A and 2 B, the systems
may be split such as shown in dotted lines in FIG. 2 so
that the inlet piping from pump 21A may extend di
rectly as through piping or inlet line 32A into a sepa
rate entry pipe 34A, while the inlet to the tank 51 from
dosing pump 21 B may be in a like manner split as at
32B and enter into a separate inlet line as at 34B. Ifde
sired, the pipes 34A and 34B may be joined at the cen
tral portion of the tank as by a valve (not shown) so
that the systems may be segregated orjoined together.
The placement of a valve intermediate the two lines
will permit the use ofjust one pump as desired and will
permit segregation of the systems in the event that re
pair or cleaning is necessary in either of the systems.
The secondary treatment apparatus ofthe illustrated
system comprises a biological reactor (as it has come
to be known in the trade) which includes a compart
mented tank 51 havinga contoured bottom with longi
tudinally spaced apart baffles or weirs (not shown) to
separate the tank into longitudinally extending com
partments. As shown in FIGS. 1-4, the reactor com
prises a rotor 55 mounted for rotation in the tank 51,
and includes at least first and second sets 60A and 60B
of radially projecting arms 61 which are spaced about
the rotor 55 and coupled thereto, the first set of arms
60A being axially spaced (see FIG. 4) from the second
set of arms 60B. In accordance with the invention, a
plurality of groups 70 of spaced apart pie or wedge
shaped elements are arranged in superimposed, juxta
position relation. Eachgroup 70 elements is positioned
intermediate adjacent radially projecting arms 61 of
each of the first and second sets 60A and 60B, the
groups forming thereby a plurality ofdisks 71 extend
ing along the rotor 55. Coupling means 72 releasably
couple each group ofelements 70 to the arms 61. Drive
means 52, in the illustrated instance an electric motor
(see FIG. ), effect a slow rotation ofthe rotor so as to
cause atleasta partial sumbersion ofthe groups ofele
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ments into the waste media in the tank during each ro
tation of the rotor.
in accordance with the invention the groups interme
diate the longitudinally separated radially extending
arms 6 of the set of arms 60A and 60B comprise Sets
of thin, wedge or pie shaped elements 73 and 74, the
elements 73 forming a first set, and the elements 74
forming a second set. Each of the elements ofa set has
opposite major surfaces 73A, 73B, 74A, 74B and ar
ranged so that elements of the first set are interdigi
tated with respect to the elements of the second set to
thus form a group.70. As will be more fully explained
hereinafter, the elements of each set are designed for
mating in nested relationship with other elements of its
own set, and adapted for a coacting spaced apart rela
tionship and alignmentwith elements ofthesecond set.
Each of the elements of each of the sets of elements
includes a plurality of protrusions 75 and depressions
76 therein, the protrusions and recessions, in the illus
trated instance, being substantially identical in the
plane ofthe major surfaces, although in FIG.6 to avoid
an optical illusion, the depressions76 are shown merely
as rectangles while the protrusions 75 are shown in de
tail. As shown in FIG. 6A, each ofthe protrusions and
depressions is preferably in the form of truncated
pyramids, which, due to the thinness of the material
used (such as polypropalene, polyethelene, etc.) serves
to stiffen the wedge shaped element.As illustrated best
in FIG.6, each ofthe protrusions and depressions is ad
jacent one another in a preset predetermined pattern,
which aids in the stability of the segment or element
and adds to increase the effective surface area thereof.
Circumscribing each ofthe elements in a broken array
is an upstanding rib 77 which projects from one major
surface of the elements, the rib serving, in a like man
ner, to stiffen the element in conjunction with a central
rib or the like 78. Further stiffening action is obtained
by the short ribs 79 which project from the rib 77, at
various portions therealong. For purposes which will
become more clear hereinafter, the protrusions 75 of
the elements 73 of the first set are arranged to mate
with like protrusions in the elements 74 of the second
Set.
In order to maintain the elements of one set in inter
digitated spaced apart relation with respect to the ele
ments of the other set, integral spacer and alignment
means are preferably formed in the elements 73 and
74. To this end, and referring now to FIGS. 6, 6A, 6B
and 7, each of the elements 73 and 74 includes integral
spacers which cooperate with receptacles in the adja
cent elements. In the illustrated instance, alternate
ones of the protrusions 75 have a cone shaped projec
tion 75A, while intermediate protrusions have a recep
tacle or dimple 75B. The projections 75A and recepta
cles 75B of the elements 73 being offset from the pro
jections and receptacles of the elements 74. Addition
ally the ribs 77 and central rib 78 include spacers or
projections 80 which alternate with receptacles or dim
ples 81, the spacers and receptacles of one set of ele
ments 73 being offset with respect to like parts on the
elements 74. The projections or spacers 75A and 80
may take any suitable form, in the present instance sub
stantially conical, the tip abutting in the flat bottom of
the receptacle in the adjacent element. The spacers
serve to position the adjacent elements of the opposite
set a predetermined distance apart to permit the
growth ofbiological mass therebetween while effecting
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maximum surface contact of each ofthe elements with
the waste media, permitting the waste water or media
to drain from the elements as they are raised out ofthe
tank by rotation and effecting maximum exposure of
the biological slime to air.
Additionally, and as illustrated in FIG. 7, it may be
desirable to provide integral alignment means so that
the elements which are interdigitated may lock one to
the other to effect not only rigidity ofthe group, but to
prevent inadvertent displacement of one element with
respect to the other. To this end, the alignment means
82 comprises a pocket 83 which frictionally engages a
latch.84 in the adjacent element. Each of the elements
includes both pockets and latches, the pockets in one
element ofaset adapted for coacting frictional engage
ment with latches of the adjacent element, when one
element of a set is mated with an element of another
set.As best illustrated in FIG. 6, the pockets 83 are re
inforced by radially extending ribs 87 which aid in giv
ing to the pockets a spring like action when the latch
84 enters into the pocket.
itshouldbe recognized that in certain constructions,
it may be desirable to make a unitized construction of
the elements forming a group. To fabricate such a con
struction it is a simple matter to effect a preselected
points localized heating of adjacent elements.For ex
ample, the latches 84 may be spot welded, the bottom
83A ofthe pocket, the weld being easily affected in as
sembling the elements by an application of heat to the
pocket and tip of the latch 84 as the elements are as
sembled forming thereby an intergral structure of the
group. Of course the elements may take many forms,
which lend themselves to localized spot welding of one
element to the other by spot heating. For example, and
as shown in FIG. 9, elements 173 and 174 having pro
trusions 175 and depressions 176 may include integral
alignment means 82 which comprise stepped pockets
183 which cooperate in frictional engagement with like
formed latches 84. In theillustrated instance, to facili
tate such welding process, the latch 184 includes a flat
184A at the upper portion thereoffor intimate contact
with the interior surface 183A of the pocket. The flat
surface to flat surface contact facilitates the welding of
the two surfaces one to the other merely by heating, for
example with a hot iron, the outside of the pocket.
Each of the elements of a set is adapted for nesting
with elements of its own set to make a compact pack
age for shipment purposes from, for example, a manu
facturing source.Such a stack of elements is illustrated
in FIGS. 8 and 10 wherein the elements may be either
of the sets 73, 74 or as shown in FIG.10, the elements
173 or 174. In either case, these drawings illustrate the
compact and nested arrangement of the elements one
with respect to the other which facilitates their package
ing for shipment.
After the elements have been shipped to some loca
tion, either the job site or the fabrication place, they
are assembled into the form best illustrated in FIGS. 6
and 7. After assembly the elements 73 being interdigi
tated with the elements 74, to form a group 70, a rod
88 is placed through the group 70, and more specifi
cally through an aperture or the like 89 which extends
through each ofthe elements ofeach set, the aperture
in the illustrated instance (see FIG. 6) being formed
through the central rib 78. As shown, the rod 88 ex
tends beyond the group 70. The assembled group is
then coupled between adjacent arms 6 ofthe first and
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second sets ofarms 60A and 60B. To this end, the arms
61 comprise T shaped members which are coupled at
their base to a plate 90 which is keyed on the rotor 55.
As best illustrated in FIGS. 3 and4,the arms 61 include
cross brace members 62 which extend intermediate the
arms circumscribing the plate 90 and thus the rotor 55.
The rotor 55, as shown, is rectangular in cross section
and houses a cylindrical shaft 56 which is anchored in
the rotor as by gusset plates or the like 57A. The plate
90 includes a rectangular aperture 90A which mates
with the rectangular rotor 55, whereby when the rotor
rotates the arms are carried therewith.
In order to properly position the plates 90 on the
rotor 55, the shaft 56 is bolted to a capture plate 57, in
the present instance generally cross shaped, having ap
ertures or holes 58 at the extended ends of the cross.
Rods 59 which extend through the apertures 58 are
suitably sleeved as at 59A, 59B and extend the entire
length ofthe rotor, the rods 59 in conjunction with the
sleeves serving to set the proper spacing between the
plates 90 and functioning to hold the plates axially of
the rotor so as to prevent inadvertent axial movement
thereof, while permitting the placement ofgroups70 of
the elements as hereinafter described. As shown, the
rods may be suitably threaded and held in place to the
capture plate 57 as by nuts 59C.
In order to secure the groups 70 to form the disks 71,
coupling means 72 are provided to couple the groups
intermediate the adjacent arms ofa set 60A and axially
intermediate the first and second set of arms 60A and
60B. In the present instance the coupling means are
connected to the cross braces 62 and comprise a U
shaped receiver 73 having an aperture 73A therein to
receive the extended ends of rod 88. To hold the rods
in the aperture 73A a cap 74 is provided which may be
screwed to the U shaped member in a conventional
manner as shown in FIG. 3A. Thus the rods 88 are low
ered into the aperture 73A and then held in place by
the cap 74 to prevent the groups 70 from dropping
from the sets of arms when the rotor rotates the arms
61 into the tank 51. Once the group ofelements have
been coupled in the manner described to the braces 62
intermediate the arm 61, a plurality of disks is formed
nad thereafter the apparatus may be utilized in the con
ventional manner.
It should be recognized that any number of means
may be employed to connect the groups ofelements 70
together and to the rotor to form the disks 71. For ex
ample, the elements, once formed in a group, may be
wrapped with a band to hold the elements in mating re
lation. In this connection the elements may be notched
or slotted along their periphery, as at 'X' so that the
band may fit in the notch and wrap the group. The
group 70 may then be secured, as before, by the rod 88
to the sets of arms.
Additionally the groups 70 may be secured, either in
the wrapped or unwrapped form by clamping the
groups in a manner to wedge them intermediate the ra
dially diverging arms 61 of the sets of arms 60A and
60B. To this end and referring now to FIGS. 11-13,
arms 6 may be provided with caps, in the illustrated
instance comprising L-shaped brackets 91 which may
be secured to the flange 61A ofthe T-shaped arms 61
as by bolts 92. Straps 93 and 94 may then be criss
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crossed over the group 70 and secured to the caps to
press the group into the space intermediate adjacent
arms 61 of the sets of arms 60A and 60B. The straps
may be adjustably coupled to the caps as by passingthe
same through obtusely arranged pipes 95 and 96 con
nected to the caps. The straps may be kinked at either
side of the pipe as at 97 and 98 and a bolt 99 passed
through apertures in the kinks to permit tensioning of
the straps. Alternately, ofcourse, a turnbuckle arrang
ment may beprovided to connect the straps to the arms
61 and to effect proper tensioning of the straps.
Itshould be recognized that the elements of the pres
ent invention give a significant economic advantage in
both shipping and in makeup prior to placement at the
15 job site. Additionally, the construction ofthe same per
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mits more rapid construction ofthe plantsite and faster
in place service of the secondary treatment apparatus
50.
Although the invention has been described with a
certain degree ofparticularity, it is understood that the
present disclosure has been made only by way ofexam
ple and that numerous changes in the details of con
struction, the combination and arrangement of parts,
and the method ofoperation may be made without de
parting from the spirit and the scope of the invention
as hereinafter claimed.
What is claimed is:
1. Biological mass growing media for attachment to
the rotor of a rotating biological reactor, said media
comprising: a group of thin wedge-shaped elements
each having opposite planar major surfaces and each
surface havinga pattern ofprotrusions and depressions
therein; said elements ofsaid group including coacting
projections and receptacles in adjacent elements, at
least some ofsaid coacting projections and receptacles
on said adjacent elements serving as spacer means in
termediate each ofsaid elements to effect a predeter
mined spacing of said elements one from the other;
alignment means in each of said elements to insure
alignment of adjacent elements one to the other, said
alignment means including pockets in each ofsaid ele
ments and latch means in each of said elements; said
pockets in one element aligning and cooperating for
engagement with latches in an adjacent element.
2. A biological mass growing media in accordance
with claim 1 wherein said latches of one element enter
into said pockets ofan adjacent element and are fric
tionally engaged by said pockets.
3. A biological mass growing media in accordance
with claim 1 wherein said latches and pockets are con
nected together after engagement one with the other.
4. A biological mass growing media in accordance
with claim 1 including radially extending ribs circum
scribing said pockets.
5. A biological mass growing media in accordance
with claim 1 including a rib adjacent the periphery of
said elements.
6. A group ofelements for a biological reactor in ac
cordance with claim 2 wherein when said first and sec
ond set of elements are arranged in a group, the ele
ments ofsaid first set are arranged in interdigitated su
perimposed relationship with respect to the elements of
said second set.
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