The document describes a non-chemical cooling water treatment system called VRTX that uses controlled hydrodynamic cavitation to control bacteria like Legionella. It works by passing water through a mechanical unit that subjects it to rapid changes in pressure and vacuum, hydrodynamic cavitation, and collision forces that rupture bacterial cell walls. Laboratory and field tests showed it can effectively eradicate bacteria in cooling water systems. The system produces calcium carbonate precipitates that prevent scale buildup and keeps corrosion rates low. It provides a non-chemical alternative to traditional cooling water treatment methods.
This document discusses cooling water problems such as corrosion, scale, fouling, and microbiological contamination. It explains the causes and factors that influence these problems, as well as methods to control and prevent each problem. Key topics covered include the corrosion process, scale formation mechanisms, types of fouling, factors influencing microbial growth, and chemical treatment options for control and prevention.
This document provides an overview of cooling water treatment. It defines a cooling tower as a heat rejection device that uses evaporation to lower the temperature of a water stream. It describes the different types of cooling towers and their designs. It then discusses the normal terminology used in open recirculating cooling water systems, including hold up capacity, blowdown, drift loss, evaporation losses, system losses, and concentration cycle. The document goes on to explain issues like corrosion, scaling, fouling, and deposition in cooling water systems and how treatment addresses them. It provides details on phosphate corrosion technology and scale formation. It also covers microbiological fouling and the factors influencing bacterial growth. Finally, it discusses cooling water treatment methods for corrosion,
This document summarizes a plant chemistry report on reverse osmosis systems. It covers topics like water properties, sea water impurities, the anatomy and principles of reverse osmosis systems. It also discusses common problems like boron removal, high pH scaling issues, membrane oxidation, and fouling causes like suspended solids, microbiological growth, and silica. Troubleshooting methods involving pressure vessel probing and single element performance tests are presented.
1. The document summarizes a study that evaluated the effect of mixed corrosion inhibitors in a cooling water system. Carbon steel specimens were immersed in mixtures of sodium phosphate and sodium glocunate at different concentrations and temperatures.
2. The corrosion inhibitors efficiency was calculated to be 98.1% using inhibited versus uninhibited water. The corrosion rate decreased with higher inhibitor concentration and temperature, with the lowest rate of 0.014gmd at 80 ppm and 100°C for 5 days.
3. Corrosion occurs electrochemically when an electric current flows from one part of a metal to another through water. Various factors like dissolved solids, pH, alkalinity, and hardness affect corrosion
This document provides an overview of cooling water problems and solutions. It discusses common issues like scaling, corrosion, and biological growth that result from poor water quality. The document then covers critical water parameters like conductivity, pH, alkalinity, hardness, and saturation index. It explains different types of scale and methods to control scale, such as water softening, pH adjustment, controlling concentration cycles, and chemical treatment. The focus is on maintaining water quality to prevent problems and reduce maintenance costs for cooling systems.
The presentation discussed various types of aeration processes used in water treatment including mechanical aeration methods like packed column aeration. It also summarized key applications of aeration like removal of hydrogen sulfide, iron, manganese and ammonia. The presentation concluded with an overview of aeration systems and design criteria for diffused aeration commonly used for removal of volatile organic compounds.
This document discusses wastewater management in industries. It outlines the objectives of understanding wastewater quality requirements, design, and disposal methods for different industries. It covers sources of water, water quality parameters, common water impurities, and pretreatment methods like softening, filtration, and ion exchange. The document also discusses the importance of water quality for food processing industries and methods to reduce waste volumes, like classifying wastes, conserving water, changing production processes, and reusing effluents.
The document discusses the processes of mixing, coagulation, and flocculation in water treatment. It defines coagulation as destabilizing particles in water so they can attach to other particles and be removed. Flocculation is the formation of larger particles called flocs. Key factors that affect these processes are mixing conditions, pH, alkalinity, temperature, and turbidity. Common coagulant chemicals like alum and ferric salts are added for coagulation. Flocculation aids like polymers can help form stronger flocs. Proper process control includes monitoring these factors. Rapid mixing distributes coagulants uniformly while flocculation encourages floc formation.
This document discusses cooling water problems such as corrosion, scale, fouling, and microbiological contamination. It explains the causes and factors that influence these problems, as well as methods to control and prevent each problem. Key topics covered include the corrosion process, scale formation mechanisms, types of fouling, factors influencing microbial growth, and chemical treatment options for control and prevention.
This document provides an overview of cooling water treatment. It defines a cooling tower as a heat rejection device that uses evaporation to lower the temperature of a water stream. It describes the different types of cooling towers and their designs. It then discusses the normal terminology used in open recirculating cooling water systems, including hold up capacity, blowdown, drift loss, evaporation losses, system losses, and concentration cycle. The document goes on to explain issues like corrosion, scaling, fouling, and deposition in cooling water systems and how treatment addresses them. It provides details on phosphate corrosion technology and scale formation. It also covers microbiological fouling and the factors influencing bacterial growth. Finally, it discusses cooling water treatment methods for corrosion,
This document summarizes a plant chemistry report on reverse osmosis systems. It covers topics like water properties, sea water impurities, the anatomy and principles of reverse osmosis systems. It also discusses common problems like boron removal, high pH scaling issues, membrane oxidation, and fouling causes like suspended solids, microbiological growth, and silica. Troubleshooting methods involving pressure vessel probing and single element performance tests are presented.
1. The document summarizes a study that evaluated the effect of mixed corrosion inhibitors in a cooling water system. Carbon steel specimens were immersed in mixtures of sodium phosphate and sodium glocunate at different concentrations and temperatures.
2. The corrosion inhibitors efficiency was calculated to be 98.1% using inhibited versus uninhibited water. The corrosion rate decreased with higher inhibitor concentration and temperature, with the lowest rate of 0.014gmd at 80 ppm and 100°C for 5 days.
3. Corrosion occurs electrochemically when an electric current flows from one part of a metal to another through water. Various factors like dissolved solids, pH, alkalinity, and hardness affect corrosion
This document provides an overview of cooling water problems and solutions. It discusses common issues like scaling, corrosion, and biological growth that result from poor water quality. The document then covers critical water parameters like conductivity, pH, alkalinity, hardness, and saturation index. It explains different types of scale and methods to control scale, such as water softening, pH adjustment, controlling concentration cycles, and chemical treatment. The focus is on maintaining water quality to prevent problems and reduce maintenance costs for cooling systems.
The presentation discussed various types of aeration processes used in water treatment including mechanical aeration methods like packed column aeration. It also summarized key applications of aeration like removal of hydrogen sulfide, iron, manganese and ammonia. The presentation concluded with an overview of aeration systems and design criteria for diffused aeration commonly used for removal of volatile organic compounds.
This document discusses wastewater management in industries. It outlines the objectives of understanding wastewater quality requirements, design, and disposal methods for different industries. It covers sources of water, water quality parameters, common water impurities, and pretreatment methods like softening, filtration, and ion exchange. The document also discusses the importance of water quality for food processing industries and methods to reduce waste volumes, like classifying wastes, conserving water, changing production processes, and reusing effluents.
The document discusses the processes of mixing, coagulation, and flocculation in water treatment. It defines coagulation as destabilizing particles in water so they can attach to other particles and be removed. Flocculation is the formation of larger particles called flocs. Key factors that affect these processes are mixing conditions, pH, alkalinity, temperature, and turbidity. Common coagulant chemicals like alum and ferric salts are added for coagulation. Flocculation aids like polymers can help form stronger flocs. Proper process control includes monitoring these factors. Rapid mixing distributes coagulants uniformly while flocculation encourages floc formation.
This document discusses cooling water chemistry and chemical treatment. It outlines the sources and typical chemistry of cooling water makeup. Key factors that must be controlled include calcium carbonate, chlorides, pH, and suspended solids. Major cooling water problems are corrosion, scaling, biofouling, and fouling. Chemicals added to control these include zinc phosphate for corrosion inhibition, scale inhibitors, oxidizing and non-oxidizing biocides, and dispersants. Maintaining proper cooling water chemistry limits is important for the effective functioning and protection of cooling systems.
This document discusses cooling water treatment at a fertilizer plant in India. It provides details on the plant's cooling towers and water chemistry parameters. Cooling water treatment is needed to prevent corrosion, scaling, and microbial fouling of the system. Common issues like corrosion, scaling, and biofouling are discussed along with the mechanisms of corrosion inhibition, scale inhibition, and microbial control through chemical treatment.
Power plant chemistry external water treatmentumar farooq
The document provides information about power plant chemistry and external water treatment. It discusses basic chemistry concepts, water chemistry, types of hardness, and external water treatment methods like softening, demineralization, and desalination. It also covers a marine ecology survey conducted by a WSP auditor at Shuaibah Sea that observed fish and algae but no live hard coral near the outfall pipe due to turbid water from the plant.
This document discusses cooling water treatment in cooling towers. It covers cooling tower concepts and types including spray ponds, natural draft, induced draft, and forced draft towers. It also discusses design factors like circulation volume and temperature change. Key water treatment issues addressed include corrosion, scaling, fouling, and microbiological growth. Solutions discussed include corrosion inhibitors, scale inhibitors, dispersants, and biocides. Existing chemical products used at the plant are also listed.
1) Cooling tower water quality must be carefully managed to prevent problems like scale formation, corrosion, and biological fouling.
2) Left unattended, the water can support biological growth and corrode or scale equipment. Proper treatment includes monitoring cycles of concentration and blowing down water to control solids levels.
3) Poor water maintenance leads to reduced efficiency from scale, corrosion from deposits, and biological fouling of the cooling tower fill. Water treatment strategies include controlling cycles, inhibiting scale and corrosion, and biocide addition.
Raw Water Intake & Pre Treatment of Raw Water in a Thermal Power PlantSUDHEER KUMAR KALYANAM
The document discusses the treatment process for raw water from rivers and lakes. It describes how raw water contains physical, biological, and chemical impurities. The treatment process involves intake, screening, pre-chlorination, storage, aeration, coagulation, flocculation, clarification, filtration through sand and activated carbon, and storage of filtered water. This multi-stage process removes suspended solids, bacteria, algae and other contaminants to produce portable water suitable for drinking and industrial use.
The document discusses a water treatment seminar that covers properties of water, pH, chiller and cooling tower operation, and common problems in cooling tower water like scale, corrosion, fouling, and microbiological fouling. It explains how water treatment chemicals can prevent scale through crystal distortion and dispersancy, and inhibit corrosion through the formation of protective films on metal surfaces. Proper bleed-off is also important to control mineral concentrations and prevent scale formation.
The document discusses reverse osmosis based desalination, focusing on developments in reverse osmosis membrane technology. It begins with an overview of desalination techniques, highlighting the importance of reverse osmosis. It then describes the reverse osmosis process and membrane types that have been developed, including cellulose acetate, thin film composite, and thin film nanocomposite membranes. The use of nanoparticles is discussed as a way to enhance membrane properties and address challenges like fouling and chlorine resistance. Overall, the document outlines the history and current state of reverse osmosis membrane technology and its role in seawater desalination.
Biological oxygen demand (BOD) refers to the amount of oxygen used by bacteria to break down organic matter in water. High BOD can deplete oxygen levels and harm aquatic life. Sources of organic matter include natural inputs like plant debris and human/industrial inputs from facilities like wastewater treatment plants. Wastewater treatment is a multi-step process involving primary treatment to remove solids, secondary treatment using microbes to break down organic carbon, and sometimes tertiary treatment to further reduce nutrients. The goal is to make water safe to return to the environment while eliminating pathogens.
Water Treatment Processes:- Coagulation , Flocculation, Filtration by Kalpesh...kalpesh solanki
The document discusses various processes involved in water treatment, including coagulation, flocculation, and filtration. It provides details on each major step:
- Coagulation involves adding chemicals like aluminum sulfate to destabilize particles in water and allow them to agglomerate. Flocculation then forms these particles into larger flocs to facilitate their removal.
- Filtration passes water through filter media like sand to remove remaining particles and microorganisms. Slow sand filters have a biological layer that assists with removal, while rapid sand filters use physical filtration at higher flow rates.
- Other key processes discussed include sedimentation to remove settled particles, aeration to improve odor and taste, and disinfection to kill
Aeration is the process of bringing water and air into close contact to remove dissolved gases like carbon dioxide and oxidize dissolved metals such as iron. It is often the first major process at water treatment plants. There are two main methods of aeration - passing water through air, and passing air through water. Common reasons for aeration include oxidation of organic matter, increasing dissolved oxygen, and removing substances that cause odor or could interfere with subsequent treatment processes.
The document discusses plant chemistry and pretreatment systems for water. It covers topics like water chemistry, pretreatment processes including coagulation, flocculation, and sedimentation. It discusses the types of contaminants found in water sources and pretreatment chemicals used. The document is intended to provide training on identifying chemical hazards, water quality control, and troubleshooting pretreatment systems.
The document discusses aeration in water treatment. Aeration serves several purposes including increasing dissolved oxygen, removing gases like hydrogen sulfide and methane, and oxidizing iron and manganese from soluble to insoluble states. Common aerators used are gravity aerators, fountain aerators, injection aerators, and mechanical aerators. Gravity aerators expose water to atmosphere using cascades or multi-tray designs. Injection aerators introduce fine air bubbles using perforated pipes or diffusers. Aeration converts iron and manganese into insoluble forms that precipitate out for removal.
Industries use water that obtained from the water treatment system for a variety
of purposes, such as:
- For manufacturing goods.
- For heating.
- For cooling.
- As carrier of raw material.
- As carrier of waste matter.
- As a solvent.
● The resulting water is then classified as a wastewater.
If a waste stream is found to be hazardous due to corrosivity, neutralization is the primary treatment used. It is used as a pretreatment system before a variety of biological, chemical, and physical treatment processes.
It is the process of adjusting the pH of water through the addition of an acid or a base, depending on the target pH and process requirements. Some processes such as boiler operations and drinking water standards need neutral water at a pH of 7.
Removal of boron from aqueous solution using reverse osmosisakhilesh kushwaha
This document presents information on removing boron from water using reverse osmosis (RO). It discusses the health risks of boron in drinking water and various boron removal methods. It outlines the RO process, factors that affect it like pH, pressure and temperature. Experimental results show boron rejection increased with higher pH and pressure. The conclusion is that RO can effectively remove boron when optimizing operating conditions.
Feed water treatment methods include internal treatment processes like zeolite treatment and demineralization, and external treatment processes like mechanical and chemical treatment. Demineralization, or ion exchange, involves removing ionic substances from water using cation and anion exchange resins to produce essentially distilled water. In the demineralization process, raw water first passes through a cation exchanger to remove bicarbonates and is then passed through an anion exchanger to remove chlorides, sulfates, and nitrates, exchanging them for hydrogen and hydroxyl ions. The treated water is then passed through a degasifier tower to remove carbon dioxide by contacting the water with low pressure air.
How Reverse Osmosis Water Purification Systems WorkAlisha Roy
Reverse Osmosis is a process in which dissolved inorganic solids (such as salts) are removed from a solution (such as water). This is accomplished by household water pressure pushing the tap water through a semi permeable membrane. The membrane (which is about as thick as cellophane) allows only the water to pass through, not the impurities or contaminates. http://catalogs.indiamart.com/products/reverse-osmosis-systems.html
This document provides an overview of cleaning reverse osmosis and nanofiltration membrane elements. It discusses common types of fouling and scaling like carbonate, sulfate, organic and biological, and recommends appropriate cleaning methods. Cleaning solutions may include acids, bases, chelating agents and detergents. The document outlines the cleaning process, safety procedures, and recommends feed flow rates during cleaning based on element size and pressure. The goal of cleaning is to remove buildup and restore membrane performance by reducing pressure and increasing permeate flow.
Analysis BOD is an important parameter in identifying the extend of pollution in a water body. This presentation explains the various methods of BOD analysis as per the APHA manual
This document provides an overview of bioreactors. It begins with an introduction that defines bioreactors as engineered systems that support biologically active environments. It then discusses the role of bioreactors in biotechnology and the growth of microorganisms. The document proceeds to classify bioreactors into suspended growth and biofilm types. It provides examples of different bioreactor arrangements and discusses mass balances in bioreactors. It concludes by covering applications of bioreactors in wastewater treatment.
Fouling, in technical language, it is the general term of unwanted material which is accumulating on surfaces, such as inside pipes, machines or heat exchanger.
This document discusses cooling water chemistry and chemical treatment. It outlines the sources and typical chemistry of cooling water makeup. Key factors that must be controlled include calcium carbonate, chlorides, pH, and suspended solids. Major cooling water problems are corrosion, scaling, biofouling, and fouling. Chemicals added to control these include zinc phosphate for corrosion inhibition, scale inhibitors, oxidizing and non-oxidizing biocides, and dispersants. Maintaining proper cooling water chemistry limits is important for the effective functioning and protection of cooling systems.
This document discusses cooling water treatment at a fertilizer plant in India. It provides details on the plant's cooling towers and water chemistry parameters. Cooling water treatment is needed to prevent corrosion, scaling, and microbial fouling of the system. Common issues like corrosion, scaling, and biofouling are discussed along with the mechanisms of corrosion inhibition, scale inhibition, and microbial control through chemical treatment.
Power plant chemistry external water treatmentumar farooq
The document provides information about power plant chemistry and external water treatment. It discusses basic chemistry concepts, water chemistry, types of hardness, and external water treatment methods like softening, demineralization, and desalination. It also covers a marine ecology survey conducted by a WSP auditor at Shuaibah Sea that observed fish and algae but no live hard coral near the outfall pipe due to turbid water from the plant.
This document discusses cooling water treatment in cooling towers. It covers cooling tower concepts and types including spray ponds, natural draft, induced draft, and forced draft towers. It also discusses design factors like circulation volume and temperature change. Key water treatment issues addressed include corrosion, scaling, fouling, and microbiological growth. Solutions discussed include corrosion inhibitors, scale inhibitors, dispersants, and biocides. Existing chemical products used at the plant are also listed.
1) Cooling tower water quality must be carefully managed to prevent problems like scale formation, corrosion, and biological fouling.
2) Left unattended, the water can support biological growth and corrode or scale equipment. Proper treatment includes monitoring cycles of concentration and blowing down water to control solids levels.
3) Poor water maintenance leads to reduced efficiency from scale, corrosion from deposits, and biological fouling of the cooling tower fill. Water treatment strategies include controlling cycles, inhibiting scale and corrosion, and biocide addition.
Raw Water Intake & Pre Treatment of Raw Water in a Thermal Power PlantSUDHEER KUMAR KALYANAM
The document discusses the treatment process for raw water from rivers and lakes. It describes how raw water contains physical, biological, and chemical impurities. The treatment process involves intake, screening, pre-chlorination, storage, aeration, coagulation, flocculation, clarification, filtration through sand and activated carbon, and storage of filtered water. This multi-stage process removes suspended solids, bacteria, algae and other contaminants to produce portable water suitable for drinking and industrial use.
The document discusses a water treatment seminar that covers properties of water, pH, chiller and cooling tower operation, and common problems in cooling tower water like scale, corrosion, fouling, and microbiological fouling. It explains how water treatment chemicals can prevent scale through crystal distortion and dispersancy, and inhibit corrosion through the formation of protective films on metal surfaces. Proper bleed-off is also important to control mineral concentrations and prevent scale formation.
The document discusses reverse osmosis based desalination, focusing on developments in reverse osmosis membrane technology. It begins with an overview of desalination techniques, highlighting the importance of reverse osmosis. It then describes the reverse osmosis process and membrane types that have been developed, including cellulose acetate, thin film composite, and thin film nanocomposite membranes. The use of nanoparticles is discussed as a way to enhance membrane properties and address challenges like fouling and chlorine resistance. Overall, the document outlines the history and current state of reverse osmosis membrane technology and its role in seawater desalination.
Biological oxygen demand (BOD) refers to the amount of oxygen used by bacteria to break down organic matter in water. High BOD can deplete oxygen levels and harm aquatic life. Sources of organic matter include natural inputs like plant debris and human/industrial inputs from facilities like wastewater treatment plants. Wastewater treatment is a multi-step process involving primary treatment to remove solids, secondary treatment using microbes to break down organic carbon, and sometimes tertiary treatment to further reduce nutrients. The goal is to make water safe to return to the environment while eliminating pathogens.
Water Treatment Processes:- Coagulation , Flocculation, Filtration by Kalpesh...kalpesh solanki
The document discusses various processes involved in water treatment, including coagulation, flocculation, and filtration. It provides details on each major step:
- Coagulation involves adding chemicals like aluminum sulfate to destabilize particles in water and allow them to agglomerate. Flocculation then forms these particles into larger flocs to facilitate their removal.
- Filtration passes water through filter media like sand to remove remaining particles and microorganisms. Slow sand filters have a biological layer that assists with removal, while rapid sand filters use physical filtration at higher flow rates.
- Other key processes discussed include sedimentation to remove settled particles, aeration to improve odor and taste, and disinfection to kill
Aeration is the process of bringing water and air into close contact to remove dissolved gases like carbon dioxide and oxidize dissolved metals such as iron. It is often the first major process at water treatment plants. There are two main methods of aeration - passing water through air, and passing air through water. Common reasons for aeration include oxidation of organic matter, increasing dissolved oxygen, and removing substances that cause odor or could interfere with subsequent treatment processes.
The document discusses plant chemistry and pretreatment systems for water. It covers topics like water chemistry, pretreatment processes including coagulation, flocculation, and sedimentation. It discusses the types of contaminants found in water sources and pretreatment chemicals used. The document is intended to provide training on identifying chemical hazards, water quality control, and troubleshooting pretreatment systems.
The document discusses aeration in water treatment. Aeration serves several purposes including increasing dissolved oxygen, removing gases like hydrogen sulfide and methane, and oxidizing iron and manganese from soluble to insoluble states. Common aerators used are gravity aerators, fountain aerators, injection aerators, and mechanical aerators. Gravity aerators expose water to atmosphere using cascades or multi-tray designs. Injection aerators introduce fine air bubbles using perforated pipes or diffusers. Aeration converts iron and manganese into insoluble forms that precipitate out for removal.
Industries use water that obtained from the water treatment system for a variety
of purposes, such as:
- For manufacturing goods.
- For heating.
- For cooling.
- As carrier of raw material.
- As carrier of waste matter.
- As a solvent.
● The resulting water is then classified as a wastewater.
If a waste stream is found to be hazardous due to corrosivity, neutralization is the primary treatment used. It is used as a pretreatment system before a variety of biological, chemical, and physical treatment processes.
It is the process of adjusting the pH of water through the addition of an acid or a base, depending on the target pH and process requirements. Some processes such as boiler operations and drinking water standards need neutral water at a pH of 7.
Removal of boron from aqueous solution using reverse osmosisakhilesh kushwaha
This document presents information on removing boron from water using reverse osmosis (RO). It discusses the health risks of boron in drinking water and various boron removal methods. It outlines the RO process, factors that affect it like pH, pressure and temperature. Experimental results show boron rejection increased with higher pH and pressure. The conclusion is that RO can effectively remove boron when optimizing operating conditions.
Feed water treatment methods include internal treatment processes like zeolite treatment and demineralization, and external treatment processes like mechanical and chemical treatment. Demineralization, or ion exchange, involves removing ionic substances from water using cation and anion exchange resins to produce essentially distilled water. In the demineralization process, raw water first passes through a cation exchanger to remove bicarbonates and is then passed through an anion exchanger to remove chlorides, sulfates, and nitrates, exchanging them for hydrogen and hydroxyl ions. The treated water is then passed through a degasifier tower to remove carbon dioxide by contacting the water with low pressure air.
How Reverse Osmosis Water Purification Systems WorkAlisha Roy
Reverse Osmosis is a process in which dissolved inorganic solids (such as salts) are removed from a solution (such as water). This is accomplished by household water pressure pushing the tap water through a semi permeable membrane. The membrane (which is about as thick as cellophane) allows only the water to pass through, not the impurities or contaminates. http://catalogs.indiamart.com/products/reverse-osmosis-systems.html
This document provides an overview of cleaning reverse osmosis and nanofiltration membrane elements. It discusses common types of fouling and scaling like carbonate, sulfate, organic and biological, and recommends appropriate cleaning methods. Cleaning solutions may include acids, bases, chelating agents and detergents. The document outlines the cleaning process, safety procedures, and recommends feed flow rates during cleaning based on element size and pressure. The goal of cleaning is to remove buildup and restore membrane performance by reducing pressure and increasing permeate flow.
Analysis BOD is an important parameter in identifying the extend of pollution in a water body. This presentation explains the various methods of BOD analysis as per the APHA manual
This document provides an overview of bioreactors. It begins with an introduction that defines bioreactors as engineered systems that support biologically active environments. It then discusses the role of bioreactors in biotechnology and the growth of microorganisms. The document proceeds to classify bioreactors into suspended growth and biofilm types. It provides examples of different bioreactor arrangements and discusses mass balances in bioreactors. It concludes by covering applications of bioreactors in wastewater treatment.
Fouling, in technical language, it is the general term of unwanted material which is accumulating on surfaces, such as inside pipes, machines or heat exchanger.
Basic Thermal Power Plant Chemistry, for Operational Staff.Syed Aqeel Ahmed
The document provides an overview of water chemistry training for power plant operators. It discusses the importance of controlling water quality to prevent scale, corrosion, and biological growth in power plant systems. It covers external water treatment processes like clarification, filtration, and desalination. It also summarizes internal water treatment including oxygen scavenging, pH control, and use of chemicals like hydrazine. Key water quality parameters that are monitored like conductivity, pH, chlorides, and sodium are explained. The document provides troubleshooting guidance and emphasizes the importance of detecting condenser leakage to prevent contamination of boiler water.
1. The document discusses biofilm growth in dead legs of high purity water piping systems. Dead legs are areas of stagnant flow that can allow biofilm to grow.
2. An experiment was conducted using piping with dead legs of varying lengths (2D, 4D, 6D) and fluid velocities (0.28m/s, 0.56m/s, 1.03m/s) to measure temperature profiles. Higher velocities resulted in faster temperature stabilization, indicating better mixing that inhibits biofilm.
3. Computational fluid dynamics (CFD) modeling was also used to simulate fluid flow and temperature distributions in the dead legs. The experimental data was used to validate the CFD models.
This document provides information about troubleshooting catalytic reactors. It begins with definitions of key terms like catalyst, activity, selectivity, and sintering. It then discusses common symptoms of issues like higher than expected pressure drop, rapid decline in conversion, and temperature runaways. For each symptom, it lists possible causes such as catalyst degradation, poisoning, maldistribution of gas flow, and inadequate heat transfer. It also covers mechanisms of catalyst deactivation like thermal sintering, chemical poisoning, and mechanical fouling. Overall, the document concisely outlines how to diagnose problems in catalytic reactors based on observable symptoms and their potential root causes.
Coagulation and flocculation in watertreatment Ghassan Hadi
The document discusses various processes involved in water treatment, including coagulation, flocculation, and filtration. It provides details on each major step:
- Coagulation involves adding chemicals like aluminum sulfate to destabilize particles in water and allow them to agglomerate. Flocculation then forms these particles into larger flocs to facilitate their removal.
- Filtration passes water through filter media like sand to remove remaining particles and microorganisms. Slow sand filters have a biological layer that assists with removal, while rapid sand filters use physical filtration at higher flow rates.
- Other key processes include sedimentation to remove settled flocs, disinfection to kill pathogens, and softening to reduce water hardness
Heat is generated during fermentation that must be controlled. Common heat transfer configurations for bioreactors include jacketed vessels, internal coils, and external heat exchangers. External heat exchangers are best for heat transfer but require careful control of sterility and oxygen transfer. Internal coils can interfere with mixing and cleaning. Mass transfer in fermentation involves the diffusion of gases like oxygen across phase boundaries according to Fick's law and two-film theory. Downstream processing after fermentation includes steps like filtration, centrifugation, chromatography, and crystallization to isolate and purify products.
This document reviews research on solar desalination systems using the humidification-dehumidification process. It begins with an abstract summarizing that desalination removes dissolved minerals from saline or brackish water. The paper evaluates different system layouts and components of humidification-dehumidification systems by comparing the works of various authors. It concludes that while humidification-dehumidification technology shows promise for small-scale decentralized water production, further research is needed to improve efficiency and reduce costs.
Removal of Arsenic from Ground Water by Electrocoagulation Effluent Treatment...IRJET Journal
The document discusses the removal of arsenic from groundwater using a combination of electrocoagulation and low-cost adsorbents. It begins with an introduction to water pollution and various heavy metals like arsenic that contaminate water sources. Then it describes the process of electrocoagulation which involves using electrodes to introduce metal ions that remove impurities. The electrocoagulation is combined with an effluent treatment process using additional techniques like activated carbon, reverse osmosis and ultrafiltration to further purify the water before it is safe for consumption. The document evaluates this combined approach as an effective and low-cost means of treating arsenic contaminated groundwater.
The higher temperature at the heat transfer
surfaces increases the rate of scale formation on these surfaces, there by reducing the efficiency
and operating capacity of the unit
The document describes the process of treating waste water from communities. It involves primary, secondary and tertiary treatment stages. Primary treatment includes screening to remove solids, and sedimentation to allow grit to settle. Secondary treatment uses anaerobic digesters and activated sludge processes to break down organic waste. Tertiary treatment includes disinfection through UV light or chlorine before water is released into waterways, used for irrigation, or passed through wetlands. The goal is to remove pollutants and pathogens before water is returned to the environment.
wastewater in NZ, sewage treatment in NZ, process of wastewater in NZ, process of sewage treatment in NZ, primary secondary tertiary treatment of waste water, screening of wastewater, grit removal tanks, sedimentation, process of separation, anaerobic digestors, activated sludge, trickling filters, oxidation ponds, polishing ponds, disinfection of waste water, wetlands, irrigation, UV lamp disinfection of wastewater, chlorine disinfection of wastewater, ozone disinfection of wastewater
This document discusses water treatment processes. It describes that water treatment removes contaminants from wastewater through physical, chemical, and biological processes. The objective is to produce a safe fluid and solid waste suitable for disposal or reuse. Sewage can be treated either close to its source in a decentralized system, or collected and transported to a centralized municipal treatment plant. Key processes mentioned include screening, grit removal, primary sedimentation, biological treatment, and disinfection.
Application of Hydrodynamic cavitation as advanced oxidation process to treat...Sivakumar Kale
This document discusses the application of hydrodynamic cavitation as an advanced oxidation process to treat industrial wastewater. It begins by explaining that conventional biological treatment cannot fully degrade non-biodegradable compounds in industrial wastewater. It then introduces hydrodynamic cavitation as an alternative, describing how cavitation generates radicals that can degrade pollutants. The document outlines the experimental setup used, including a venturi tube reactor, and describes the degradation mechanisms of mechanical effects, chemical effects from radicals, and thermal effects. It presents results showing the process can oxidize over 99% of certain compounds. It concludes by discussing the need for further research on pressure profiles, reaction kinetics, and scaling the technology.
Plasma-chemical treatment of industrial wastewaters from brewery “Brasseries ...IJERA Editor
This document summarizes a study on treating industrial wastewater from a brewery in Cameroon using plasma-chemical treatment. The researchers collected wastewater samples from the central collection point of the brewery and analyzed them to determine pollution levels. They then exposed the samples to a gliding arc plasma discharge for periods of 3-60 minutes. Exposing the wastewater to 60 minutes of the plasma discharge reduced turbidity by 52.22% and absorbance by 50.19%, indicating degradation of colored compounds. After 60 minutes of treatment, levels of biochemical oxygen demand, chemical oxygen demand, and total organic carbon in the wastewater were also reduced significantly, by 52.05%, 68.63%, and 69
Plasma-chemical treatment of industrial wastewaters from brewery “Brasseries ...IJERA Editor
This work focuses on the study of the chemical reactivity of an advanced oxidation process (AOP), called the
plasma technique, in order to prevent industrial effluent from pollution and better cope to several damage of
environment. The oxidizing and acidifying properties of an electric discharge of the gliding arc plasma and its
application to a target which is a real effluent (wastewater from Brasseries du Cameroun -Bafoussam plant)
fascinated this study. Samples were collected from the central collecting point (CCP) of the effluent. The
collected effluent samples were analyzed by volumetric and instrumental methods, and then exposed to the
gliding discharge during specific time periods of 3-60 min to exhibit the desired decontamination effects. At the
end of 60 min of exposure time to the discharge, 52.22% and 50.19% obtained respectively to abatement of
turbidity and rate of fall in absorbance. This reduction can be explained by the fact that the coloured compounds
were degraded and this degradation gave rise to the transparent appearance observed. After stopping the
discharge process, the abatement percentage of BOD5, COD and TOC, were obtained at the same time (60min)
with values of 52.05%, 68.63% and 69.37% respectively. These results reflect the considerable reduction of the
pollution load of the wastewaters collected from CCP of the brewery. These results showed that the
effectiveness of the gliding arc plasma depends not only on the physico-chemical parameters of the target, but
also on the exposure time and concluded that the non-thermal plasma process alone provides good reduction of
organic pollutants in wastewater. Moreover, the phenomenon of post- discharge, even though not studied in
details demonstrated that, after switching the discharge, the evolution of parameters such as pH, electrical
conductivity and TDS increase.
Abstracts of publications in ppc whilst affiliated with sask powerEmmanuel Quagraine
1) The document summarizes 5 journal publications by Emmanuel K. Quagraine related to power plant chemistry while affiliated with SaskPower.
2) The publications provide evidence that chlorinated compounds can ingress into power plant condensers in gaseous form through weak seals or porous brass tubesheets, causing chloride contamination issues. Regression models were able to confirm this hypothesis.
3) One publication evaluates using a biologically active carbon filter in series with a granular activated carbon filter for removing organics in boiler makeup water, finding over 80% removal with the two filters working synergistically.
Ultrasonic technology uses high frequency sound waves to treat water and wastewater through a process called cavitation. Cavitation occurs when sound waves cause bubbles to form, grow, and violently collapse in the liquid, generating high temperatures and pressure that can break down organic compounds. This document reviews the science behind cavitation, including how piezoelectric transducers generate ultrasound, the formation of hydroxyl radicals, and the differences between transient and stable cavitation. Applications include suppression of algae growth and biofilm formation without using chemicals.
The document provides information about an electrostatic scale preventer system called eSCALE-OFF. It discusses how the system works by using electrostatic energy to give a positive charge to particles in water, causing them to repel each other rather than forming scale. This prevents new scale and dissolves existing scale deposits. The system requires minimal maintenance and energy to operate. It provides benefits over traditional chemical treatment systems such as lower operational costs, reduced corrosion and pollution, and elimination of chemical safety and disposal issues.
1. Evaluating Efficacy of New Technology For Bacteria & Legionella Control
Robert Kelsey, X. Terpstra HydroVRTX™ BV
Abstract
This paper describes an alternative, patented, non-chemical cooling water treatment system that
has proven to be effective in controlling/eradicating bacteria and Legionella. The VRTX system
is a side-stream treatment system and includes a mechanical VRTX unit and a
separation/filtration unit. The VRTX unit works primarily on the principals of Controlled
Hydrodynamic Cavitation (CHC). The CHC actions destroy microbial cell walls and converts
dissolved calcium and bicarbonate ions into aragonite calcium carbonate (CaCO3) colloids,
when cooling water is pumped through the VRTX unit. The separation unit is used to remove
the precipitated calcium carbonate and other suspended solids from the recirculating cooling
water to keep the cooling water system clean.
The VRTX system eradicates bacteria by a combination of synergistic actions: pressure,
vacuum, kinetic impact and shear force at the collision point, hydrodynamic cavitation, sonic
waves and oxidizing chemicals produced from cavitation. In this paper, laboratory and field
tests results are presented to demonstrate the effectiveness of VRTX system in controlling
bacteria and Legionella in cooling water systems.
Introduction
Identifying, monitoring and controlling Legionella and Legionnaires’ disease has became a
worldwide health issue and concern. Legionellosis is a collectable term describing infection
produced by the pathogen Legionella, a bacterium found water and the environment – naturally
occurring surface water as well as potable and non-potable water supplies.
The mode of Legionnaire infection is the inhalation of bacteria Legionella laden, small water
droplets (aerosol) or aspiration of contaminated water. The disease has two distinctive forms:
Legionnaires’ disease, a sever form of infection that includes pneumonia and Pontiac fever, a
milder illness.
Cooling water systems can frequently be colonized with Legionella bacteria. Several cooling
water systems can readily produce airborne water droplets (aerosol). In industry the primary
sources of airborne water droplets are cooling towers, evaporative condensers, and air wash
systems.
In this paper, a new, alternate technology is described for cooling water treatment. The system
is a patented, mechanical device using the principles of kinetic energy, chemical equilibrium
and hydrodynamic cavitation to treat fluids. Extensive laboratory testing and field tests have
shown that this non-chemical treatment method can effectively control scale, corrosion and
bacteria activities, including Legionella, in cooling water systems. The emphasis of this paper is
on bacteria and Legionella control / eradication.
2. Brief Description of Technology
VRTX system is a side-stream treatment system (see Graph 1). It includes two parts: a VRTX
unit and a separation/filtration unit (see Photo 1). The separation/filtration unit is used to
remove the precipitated calcium carbonate and other suspended solids from the recirculating
cooling water.
The patented VRTX chamber consists of a pressure equalizing chamber and a cavitation
chamber (Graph 2). Inside the cavitation chamber, two pairs of nozzles are positioned opposite
each other - at specific distances, lengths and angles. Sump water is first pump into the pressure
equalizing chamber at a pump pressure of ~70 PSI. From the equalizing chamber, water is
channeled into the cavitation chamber, where water is forced to rotate at high velocities. The
rotation of water streams creates a high vacuum, typically greater than -27.5’ Hg. This high
vacuum condition causes micro-sized bubbles to form in the water streams. These bubbles are
filled with a mixture of vapor and dissolved gases, most commonly carbon dioxide and oxygen.
The water streams in two nozzles rotate in opposite directions. Meanwhile, the water streams
To process Return from process
Separator
To drain
Graph 1: Schematic of VRTX system layout
Photo 1. VRTX Unit and Separation System Graph 2. Schematic Water Flow
Inside of VRTX Chamber
3. travel forward at accelerating speeds. Upon exiting from the nozzle, the opposite water streams
collide at the mid-point of cavitation chamber. At this point, pressure increases spontaneously,
causing the sudden implosion of micro-sized bubbles. At the moment of collapse,
hydrodynamic cavitation generates intensive shocking waves and produces extremely high
temperatures. Under these conditions, chemical reactions are forced to occur and bacteria are
ruptured by both mechanical and physical forces.
When the cooling water is pumped through the VRTX chamber, dramatic changes in velocity
and, consequently, static pressure lead to the destruction of microbial cell walls and the
conversion of dissolved calcium and bicarbonate ions into calcium carbonate (CaCO3) aragonite
colloids:
Ca2+
+ 2HCO3
-
CaCO3 + CO2 + H2O
Scale Control
The CaCO3 colloids formed under these conditions are in the form of aragonite, shown by
microscopic analysis (Photo 2). Aragonite has the same chemical composition as calcite, but
their molecular structures are quite
different. The rhombohedra calcite
crystal has six flat surfaces; these
flat surfaces lead to significant
adhesion sites and readily attach to
other surfaces and form a hard
deposit. Conversely, the shape of
aragonite is needle-like. This
unique shape substantially reduces
the adhesion sites for and to other
surfaces, and tends to form soft
deposits. Deposits and formation of
aragonite CaCO3 are more stable
upon heating and can be carried
throughout a heating or cooling
system while causing no apparent
damage and no appreciable build-
up. This transport property allows the CaCO3 particles to be removed by the filtration unit,
where they are physically separated from the recirculating water.
Energy
EnergyDissolved
bicarbonate ions
Dissolved Ca
ions
CaCO3
colloids+ Water
Carbon
dioxide
gas
+ +
Photo 2. Aragonite Crystals Formed in VRTX Treated
Water
4. Corrosion Control
By eliminating corrosion chemicals usually used in treatment, raising and maintaining pH in
alkaline range of 8.5, reducing microbiological activities, and maintaining low levels of
suspended solids, the VRTX system effectively reduces the corrosivity of recirculating waters
and keeps corrosion rates low. Chart 1 lists examples of corrosion field test results.
Bacteria Control
VRTX technology kills bacteria by a
combination of different actions: pressure,
vacuum, kinetic impact and shear force at
collision point, hydrodynamic cavitation,
sonic waves and oxidizing chemicals
produced from cavitation. The exact
mechanism is still under investigation.
Nonetheless the following summarizes two
actions that contribute to VRTX’s ability to
control and eradicate bacteria.
• Dramatic changes in pressure and
vacuum: Graph 3 illustrates the
changes of hydrostatic pressure in
water passing through the VRTX
unit.
• Typically the membrane wall of most
bacteria is fragile. Under such
dramatic and rapid pressure changes,
over an extremely short period of
Atmospheric pressure in sump
Discharge pressure (2 – 4 psi)
Pump pressure (~ 70 psi)
Near vacuum condition inside
of cavitation chamber (-27.5’ Hg)
High pressure and shear created by the collision
of water streams at the mid-point of chamber
Atmospheric pressure in sump
Graph 3. Changes in Pressure of Water
Passing VRTX Unit
Chart 1. Recent Corrosion Test Results
5. Collapsing
bubble
Microjet
Solid
Photo 3. Microjet created by cavitation
time (several micro seconds), the membrane wall is weakened or damaged. The direct
impact of shear and collision forces created by the collision of water streams also
contributes to rapture the membrane. Once the membrane is broken, the liquid
components inside the cell will leak out, leading to the death of bacteria. In addition,
extracellular polymeric substance (EPS) associated with biofilm and which surround and
protect free-floating bacteria is readily stripped away and destroyed.
• Hydrodynamic cavitation:
• Microjet – When micro-sized bubbles collapse near a suspended solid or bacteria,
it implodes asymmetrically. A jet of liquid is formed on the side of bubble
opposite the bacteria and penetrates through the bubble at ~ 250 mil/hr. A
microjet is strong enough to
puncture metal plates, causing
the premature pump
failures. It can easily
punch through the cell
wall of bacteria.
• Intermediate species – Cavitation results in extremely high temperatures and
high pressures in localized areas. As a result, water molecules are split up and
form free radicals:
H2O →→→→ H + OH•
The dissociation of water is thought to be produced by electrical discharges
resulting from hydrodynamic cavitation or by thermal dissociation due to adiabatic
compression of the collapsing bubbles. Hydroxyl radicals can combine to form
hydrogen peroxide:
OH• + OH• H2O2
Hydrogen peroxide is also formed by the reaction between hydrogen atoms and
dissolved oxygen in water:
H + O2 HO2*
HO2
• + HO2
• H2O2 + O2
These species are unstable and exist for short periods of time. However, they are
continuously generated which contribute to bacteria kill.
On summary, it is believed that the synergistic combination of actions, dramatic changes
in pressure, vacuum, impact, sheer and hydrodynamic cavitation, contribute to the eradication of
microorganisms.
6. Laboratory Evaluations
The effectiveness of VRTX in eradicating bacteria has been demonstrated over several years by
field tests and independent third party evaluations.
Chart 2. Summary of Five Years of Laboratory Testing
- E. Coli -
1 pass 2 passes 3 passes
Chart 3. Examples of Repetitive Testing
- E. Coli -
7. Field Tests
1 pass 2 passes 3 passes 4 passes 5 passes
! " # $ % & '
Chart 4. Example of Laboratory Testing
- Heterotrophic Bacteria -
Chart 5. Total Bacteria In Cooling Towers
9. Legionella Tests
Laboratory Testing – Lab grown Legionella
I. Pneumophila sg -1
Dechlorinated tap water
Not temperature controlled
Standard VRTX unit – 70 psi
0%
20%
40%
60%
80%
100%
0 10 20 30 40 50 60
NUMBER OF PASSES THROUGH VRTX
PERCENTKILLED
70
90
110
130
150
170
TEMPERATRURE(F)
100
1,000
10,000
100,000
7/17 7/27 8/6 8/16 8/26 9/5 9/15 9/25 10/5 10/15
Colonies/Coupon
3 4 + , + 5 6
$ 1 7 5 6
Chart 8. Sessile Bacteria In Evaporative Condensers
(Food Manufacture – Chanhassen, MN)
Chart 9. Initial Laboratory Testing at Special Pathogens
Laboratory, VA Medical Center, Pittsburgh, PA
10. 1
1
0
100
1000
1000
0
100000
1000000
1000000
0
0 60 120 180 240 300 36
0Time, minute
E.coliconcentration,cfu/mL
1
1
0
100
100
0
1000
0
100000
0 6
0
120 180 240 300 360
Time, minute
Legionellaconcentration,cfu/mL
Control
Chart 9. Test Results at Special Pathogens Laboratory, VA
Medical Center, Pittsburgh, PA (Lab Grown E – Coli)
Chart 10. Test Results at Special Pathogens Laboratory, VA
Medical Center, Pittsburgh, PA (Naturally Grown Legionella
Pneumophila serogroup I)
Control
Test
Control
Test
11. Legionella Field Testing – Cooling Tower
Chart 11. A food manufacture plant – Chicago, IL
Conclusion
VRTX technology is a non-chemical alternative for controlling scale, corrosion and bacteria.
VRTX is targeted for industrial applications (process streams and wastewater streams) and
cooling water systems, cooling towers, condensers and air washers. In these applications scaling
and corrosion are not limiting factors, as they are successfully treated by VRTX. VRTX’s
ability to control/eradicate bacteria is not compromised by moderate to high levels of TDS,
TSS, alkalinity and hardness typically found in industrial cooling water systems.
Overall, there are several common ways to control and eradicate Legionella. Biocides, both
oxidizing and non-oxidizing, have proven to be effective in potable, non-potable and industrial
cooling water applications. However, the use of biocides causes environmental concerns and are
subject to ever-increasing legislation -- some will be banned and alternatives will be costly.
The use of copper and silver ionization has proven to be effective in laboratory testing and
field-testing. This method is very effective in potable water systems. In non-potable water
systems, especially in cooling towers and evaporator condensers, cycles of concentration can be
above 3, causing the alkalinity and hardness levels to increase, notably calcium levels.
Increased hardness in the recycled water will cause scaling to occur on the electrodes and the
effectiveness can be reduced. Additionally, bacteria resistance can build over a period of time.
Ultraviolet is also effective in potable water systems but, again, it is less effective in non-
potable water systems and in cooling water systems such as cooling towers and evaporator
condensers, where calcium carbonate and/or other solids will deposit on the lamps. In
* 8 # 8 * 9 : ; 7 "
$ 1 7
+ 1 #
3 4 + , 1 #
/ 0
12. wastewater treatment applications and cooling water treatment applications, scaling frequently
occurs and cleaning of the UV lamps is sometimes required on a daily basis. In addition, UV
may not kill Legionella presence in biofilms and, if biofilms are present, UV must be used in
conjunction with other treatment methods.
Ozone is effective in potable water but is not as effective in non-potable water and cooling
water systems. The strong oxidation potential of ozone is what makes it most attractive for use
as a biocide in water systems. However, it becomes less effective when there is chemical
oxygen demand (COD) present. The organic matters in water will consume the available ozone.
The strong oxidation potential of ozone makes it corrosive to some materials such as rubber
fittings, gaskets, and certain kinds of metals and alloys. In addition, numerous field tests have
indicated that ozone has no capability to control scale formation in cooling water systems.
The fundamental principles of VRTX allow it to be used in cooling water systems. It has been
successfully tested under laboratory and proven effective in field conditions on both lab-grown
and naturally grown Legionella over an extensive period of time. Equally important have been
several field studies and case histories.
Refs: Dr. Janet Stout of the Special Pathogens Laboratory
VA medical Center Pittsburg PA