Hazardous Waste Management:Overview Waste Management
Definition of Hazardous Waste   A solid or liquid wastes which because of its quantity, concentration or physical, chemical or infectious characteristics, may: Cause  increase  in mortality or severe illness, Pose a substantial potential  hazard  to human health or environment, when improperly  treated ,  stored ,  transported  or  disposed
Definition of Hazardous Waste
Characteristics of Hazardous Waste   Ignitability  (flash point >60 o C) Corrosivity  (pH <2 or >12.5) Reactivity  (unstable materials or material that cause violent reaction when in contact with another material) Toxicity  (Leachate Test)
Nature of Hazardous Waste Management Hazardous Waste field is  interdisciplinary Requires professionals with diverse background working together to solve the complex issue of hazardous waste management  Environmental Impact and Risk Assessment Treatment, Storage and Disposal Waste Minimization, Recycling and Reduction  Management and Cost
Past Disposal Practice Soil Spreading  Pits/Ponds/Lagoons Sanitary Landfills Drum Storage Areas  Underground Storage Tanks Midnight Dumping  Uncontrolled Incineration
Waste Generation Rates By Industry
Typical Hazardous Waste Types
Why the need for HWTC?  Protect public health and the environment Reduce impact of hazardous waste on surface water and ground water Provide the means to enhance: Waste minimization  at various industrial operations, and Waste recycling
Objectives of HWTC  Avoid and minimize  environmental and health pollution risks associated with the generation, storage, collection, transport, handling, recycling, and disposal of hazardous wastes  Ensure the movement and disposal practice of hazardous wastes is always  controlled  and environmentally safe, flexible, and economically sustainable  for local conditions
Technical Feasibility  Can the wastes be  separated  at source to avoid co-mingling and  analyzed before shipping to the facility? What characteristics are the separated wastes likely to have? What  quantity  of the wastes should be considered as wastewater?
Market and Economic Feasibility  Is there a  local market  for the products of recycling? Is there an  international market  for the products of recycling? What scale of disposal  fees  is to be expected for each category of waste? What  rate of return  would a Private Sector investor expect for providing and operating a Hazardous Waste Recycling Facility?
Materials Disposed in HWTC  Liquid organic waste Oily sludge and residue from petroleum industry  Spent oil and catalysts Contaminated soil  Liquid heavy metals Acidic and basic solids and liquids  Liquid ammonia and urea Off-Specification products
Estimation of Hazardous Wastes Quantities??   Hazardous Waste Inventory: Estimate the total waste stream quantity Deduct the portion of these wastes that are being recycled or processed at the generator’s own facilities Deduct any co-mingled wastes that are impossible to separate in a cost-effective manner
Estimation of Hazardous Wastes Quantities (cont.)   Deduct waste quantities being disposed without permit Prepare an integrated treatment system for the remainder with  add-on facilities  for growth and improvement in anticipation of reducing any unauthorized disposal Propose action as necessary for treatment and disposal facilities for the co-mingled and improperly disposed wastes
HWTC Design Approach A  flexible  modular design  will provide the Project Authority with the opportunity to attract private sector investments and will minimize capital cost in the long-term Focus initially on the major polluters Provide HWTC to treat part of  the waste Initiate and monitor
HWTC Design Approach (cont.) 2. Due to the nature of the hazardous wastes and their  potential to change  characteristics and properties over time, the HWTC needs to be properly designed and equipped with facilities that are capable of safely meeting the needs of handling and disposing the hazardous waste
Description of the HWTC Liquid Waste Treatment Facility Land Farming Facility Class I Hazardous Waste Landfill Class II Regular Waste Landfill  Solidification and Stabilization Unit Incinerator
 
Important Points  The priorities of hazardous Waste management in  decreasing  order of importance: Minimization/Prevention  Treatment/Remediation Disposal
Liquid Waste Treatment Facility Separate tank farm storage for acidic and basic waste as well as drum storage area Neutralization reactors Sludge storage reactor Standby neutralization reactors to be used during maintenance
 
Activated Carbon Column
Liquid Phase Adsorption Treatment System
Industrial Wastewater Treatment
Chemical Oxidation In general the objective of chemical oxidation is to detoxify waste by adding an oxidizing agent to chemically transform waste components Chemical oxidation is a well established technology that is capable of destroying a wide range of organic molecules, including chlorinated VOCs, phenols and inorganics such as cyanide
Process Description  Chemical Oxidation is based on the delivery of oxidants to contaminated media in order to either destroy the contaminants by converting them to innocuous compounds commonly found in nature The oxidants applied are typically hydrogen peroxide (H 2 O 2 ), potassium permanganate (KMnO 2 ), ozone (O 3 )
Process Description
Land farming is the preferred technology for the treatment of oily sludge and hydrocarbon contaminated soils, which constitute the main component of hazardous organic wastes to be treated at the HWTC   Land Farming Facility
Base Liner Detail
Compounds to be treated at the land Farming Facility: Volatile Organic Compounds  (VOCs): benzene, ethylbenzene, toluene, xylenes; Semi-Volatile Organic Compounds  (SVOCs): phenols, creosol, naphthalene, phennathrene, benzo(a)pyrene, flourrene, anthracene, chrysene; and Heavy Metals : chromium, cyanides, lead and nickel Land Farming Facility (cont’d)
 
Aerobic Biodegradation  ORGANIC POLLUTANT  +  MICROORGANISMS  +  NUTRIENTS  +  OXYGEN CARBON DIOXIDE  +  WATER  +  BIOMASS HYDROCARBON PRODUCT
Microorganisms  Regarding the natural breakdown of hydrocarbon products, bacteria are the main microorganism in the bioremediation process  Bacteria act as decomposers and utilize hydrocarbon product as a source of energy
Nutrients  Nutrients enhance the biodegradation process by supplying essential elements required for optimal microbial growth and maintenance  Nutrients can be supplied in the field through the application of manure or fertilizer C:N:P = (100-300):10:1
Requirements for Biodegradation   Proper nutrient balance  Temperature  15 – 30  o C Acceptable pH  5.5 - 8.5 Moisture content of 60% - 80% of field capacity Oxygen concentration Presence of toxic heavy metals
Naphthalene Removal Efficiency
Bio-piles
Soil Composting
Hazardous Waste Landfill Class I Landfill should include: Double liner  Leachate collection  Leachate detection system Surface water control mechanism Impermeable cover system
 
Hazardous Waste Landfill
Hazardous Waste Landfill Liner System
Regular Waste Landfill Class II Landfill should include: Single liner  Leachate collection  Surface water control mechanism Impermeable cover system
Regular Waste Landfill
Solidification and Stabilization The solidification and stabilization facility (SSF) will be designed to inactivate and immobilize contaminants prior to landfilling
Solidification and Stabilization  The following waste will be processed by SSF plant prior to landfilling: Mercury contaminated solid wastes; Solid miscellaneous inorganic sulfur; Semi-solid hazardous waste; and Sludge from Liquid Hazardous Waste Treatment
Solidification and Stabilization S/S reduces the mobility of hazardous substances and contaminants in the environment through both physical and chemical means S/S seeks to trap or immobilize contaminants within their host medium (i.e. soil, sand and binding agent) Leachability testing is usually performed to measure the immobilization of contaminants from the stabilized matrix
Solidification and Stabilization General binding and sorbent materials: Cement Pozzolans Lime Silicates Organically Modified Clays
 
High Temperature Thermal Desorption HTTD is  a technology in which wastes are heated to 320 to 560  o C  Produce final contaminant concentration level below 5 mg/kg
Incinerator Structure to house the furnace  Tipping floor where the Hazardous Waste is disposed Storage pit to store the Hazardous Waste delivered  Charging system  Furnace Air pollution control  Ash handling system
HWTC Control Philosophy  Provide a Supervisory Control and Data Acquisition (SCADA).  The SCADA system will provide two levels of control:  Level 1  control operates equipment directly and bypasses all interlocks.  Level 2  is initiated directly by computer programming. Level 2 controls, operates equipment and processes remotely.
Typical Control System
Environmental Monitoring  Air Quality Groundwater Quality Surface Water Quality Dust and Noise
Environmental Monitoring  Selection of the parameters of concern Sampling methodology  Quality assurance /quality control plan
Project Approach Task 1: Review of Existing Data Task 2: Discussion with Project Authority Task 3: Development and Finalization of HWTF Design Task 4: Prepare Final Design Drawings and Design Basis Memorandum
Project Approach (cont.) Task 5: Design of Liquid Hazardous Waste Treatment Facility Task 6: Class I and II Landfills Design Task 7: Land Framing Facility Design Task 8: Solidification and Stabilization Facility Design
Project Approach (cont.) Task 9: HWTC Construction Task 10: Facility Commissioning and Operation  Task 11: Facility Handing Over
Conclusions Key to proper design of HWTC is system   flexibility   to adjust to hazardous waste quantities and properties over time Enforcement  of environmental law and regulations
Leachate Treatment Using Wetlands Department of Environmental Engineering  Beijing University of Chemical Technology  December 2003
Wetlands Wetland is define as land having the water table at, near or above the land surface or which is saturated for long enough period to promote wetland or aquatic processes as indicated by hydric soils, hydrophilic vegetation, and various kinds of biological activity which are adapted to the wet environment.
Treatment Mechanisms in a Wetland System
Type of Engineered wetlands Constructed wetland systems are classified into two general types:  Horizontal Flow System (HFS) Surface Flow (SF) Sub-surface Flow (SSF) Vertical Flow System (VFS).
Horizontal Flow Wetland System
Surface Flow Wetland System
Subsurface Flow Wetland System
Field Monitoring
Field Monitoring  Monitoring wells Pond #1 Pond #2 Peat Filter SW-1 SW-4 SW-3 SW-2 D B A C FSW-1 FSW-2 FSW-3 W-2 W-1 MW-4 MW-1 MW-2 MW-5 MW-3 Manhole Pump
Field Monitoring
Boron adsorption was directly related to organic content Peat filter was effective in treating landfill leachate The adsorption capacity of the peat can be significantly enhanced by lime addition Conclusions

Hazardous Waste Management

  • 1.
  • 2.
    Definition of HazardousWaste A solid or liquid wastes which because of its quantity, concentration or physical, chemical or infectious characteristics, may: Cause increase in mortality or severe illness, Pose a substantial potential hazard to human health or environment, when improperly treated , stored , transported or disposed
  • 3.
  • 4.
    Characteristics of HazardousWaste Ignitability (flash point >60 o C) Corrosivity (pH <2 or >12.5) Reactivity (unstable materials or material that cause violent reaction when in contact with another material) Toxicity (Leachate Test)
  • 5.
    Nature of HazardousWaste Management Hazardous Waste field is interdisciplinary Requires professionals with diverse background working together to solve the complex issue of hazardous waste management Environmental Impact and Risk Assessment Treatment, Storage and Disposal Waste Minimization, Recycling and Reduction Management and Cost
  • 6.
    Past Disposal PracticeSoil Spreading Pits/Ponds/Lagoons Sanitary Landfills Drum Storage Areas Underground Storage Tanks Midnight Dumping Uncontrolled Incineration
  • 7.
  • 8.
  • 9.
    Why the needfor HWTC? Protect public health and the environment Reduce impact of hazardous waste on surface water and ground water Provide the means to enhance: Waste minimization at various industrial operations, and Waste recycling
  • 10.
    Objectives of HWTC Avoid and minimize environmental and health pollution risks associated with the generation, storage, collection, transport, handling, recycling, and disposal of hazardous wastes Ensure the movement and disposal practice of hazardous wastes is always controlled and environmentally safe, flexible, and economically sustainable for local conditions
  • 11.
    Technical Feasibility Can the wastes be separated at source to avoid co-mingling and analyzed before shipping to the facility? What characteristics are the separated wastes likely to have? What quantity of the wastes should be considered as wastewater?
  • 12.
    Market and EconomicFeasibility Is there a local market for the products of recycling? Is there an international market for the products of recycling? What scale of disposal fees is to be expected for each category of waste? What rate of return would a Private Sector investor expect for providing and operating a Hazardous Waste Recycling Facility?
  • 13.
    Materials Disposed inHWTC Liquid organic waste Oily sludge and residue from petroleum industry Spent oil and catalysts Contaminated soil Liquid heavy metals Acidic and basic solids and liquids Liquid ammonia and urea Off-Specification products
  • 14.
    Estimation of HazardousWastes Quantities?? Hazardous Waste Inventory: Estimate the total waste stream quantity Deduct the portion of these wastes that are being recycled or processed at the generator’s own facilities Deduct any co-mingled wastes that are impossible to separate in a cost-effective manner
  • 15.
    Estimation of HazardousWastes Quantities (cont.) Deduct waste quantities being disposed without permit Prepare an integrated treatment system for the remainder with add-on facilities for growth and improvement in anticipation of reducing any unauthorized disposal Propose action as necessary for treatment and disposal facilities for the co-mingled and improperly disposed wastes
  • 16.
    HWTC Design ApproachA flexible modular design will provide the Project Authority with the opportunity to attract private sector investments and will minimize capital cost in the long-term Focus initially on the major polluters Provide HWTC to treat part of the waste Initiate and monitor
  • 17.
    HWTC Design Approach(cont.) 2. Due to the nature of the hazardous wastes and their potential to change characteristics and properties over time, the HWTC needs to be properly designed and equipped with facilities that are capable of safely meeting the needs of handling and disposing the hazardous waste
  • 18.
    Description of theHWTC Liquid Waste Treatment Facility Land Farming Facility Class I Hazardous Waste Landfill Class II Regular Waste Landfill Solidification and Stabilization Unit Incinerator
  • 19.
  • 20.
    Important Points The priorities of hazardous Waste management in decreasing order of importance: Minimization/Prevention Treatment/Remediation Disposal
  • 21.
    Liquid Waste TreatmentFacility Separate tank farm storage for acidic and basic waste as well as drum storage area Neutralization reactors Sludge storage reactor Standby neutralization reactors to be used during maintenance
  • 22.
  • 23.
  • 24.
    Liquid Phase AdsorptionTreatment System
  • 25.
  • 26.
    Chemical Oxidation Ingeneral the objective of chemical oxidation is to detoxify waste by adding an oxidizing agent to chemically transform waste components Chemical oxidation is a well established technology that is capable of destroying a wide range of organic molecules, including chlorinated VOCs, phenols and inorganics such as cyanide
  • 27.
    Process Description Chemical Oxidation is based on the delivery of oxidants to contaminated media in order to either destroy the contaminants by converting them to innocuous compounds commonly found in nature The oxidants applied are typically hydrogen peroxide (H 2 O 2 ), potassium permanganate (KMnO 2 ), ozone (O 3 )
  • 28.
  • 29.
    Land farming isthe preferred technology for the treatment of oily sludge and hydrocarbon contaminated soils, which constitute the main component of hazardous organic wastes to be treated at the HWTC Land Farming Facility
  • 30.
  • 31.
    Compounds to betreated at the land Farming Facility: Volatile Organic Compounds (VOCs): benzene, ethylbenzene, toluene, xylenes; Semi-Volatile Organic Compounds (SVOCs): phenols, creosol, naphthalene, phennathrene, benzo(a)pyrene, flourrene, anthracene, chrysene; and Heavy Metals : chromium, cyanides, lead and nickel Land Farming Facility (cont’d)
  • 32.
  • 33.
    Aerobic Biodegradation ORGANIC POLLUTANT + MICROORGANISMS + NUTRIENTS + OXYGEN CARBON DIOXIDE + WATER + BIOMASS HYDROCARBON PRODUCT
  • 34.
    Microorganisms Regardingthe natural breakdown of hydrocarbon products, bacteria are the main microorganism in the bioremediation process Bacteria act as decomposers and utilize hydrocarbon product as a source of energy
  • 35.
    Nutrients Nutrientsenhance the biodegradation process by supplying essential elements required for optimal microbial growth and maintenance Nutrients can be supplied in the field through the application of manure or fertilizer C:N:P = (100-300):10:1
  • 36.
    Requirements for Biodegradation Proper nutrient balance Temperature 15 – 30 o C Acceptable pH 5.5 - 8.5 Moisture content of 60% - 80% of field capacity Oxygen concentration Presence of toxic heavy metals
  • 37.
  • 38.
  • 39.
  • 40.
    Hazardous Waste LandfillClass I Landfill should include: Double liner Leachate collection Leachate detection system Surface water control mechanism Impermeable cover system
  • 41.
  • 42.
  • 43.
  • 44.
    Regular Waste LandfillClass II Landfill should include: Single liner Leachate collection Surface water control mechanism Impermeable cover system
  • 45.
  • 46.
    Solidification and StabilizationThe solidification and stabilization facility (SSF) will be designed to inactivate and immobilize contaminants prior to landfilling
  • 47.
    Solidification and Stabilization The following waste will be processed by SSF plant prior to landfilling: Mercury contaminated solid wastes; Solid miscellaneous inorganic sulfur; Semi-solid hazardous waste; and Sludge from Liquid Hazardous Waste Treatment
  • 48.
    Solidification and StabilizationS/S reduces the mobility of hazardous substances and contaminants in the environment through both physical and chemical means S/S seeks to trap or immobilize contaminants within their host medium (i.e. soil, sand and binding agent) Leachability testing is usually performed to measure the immobilization of contaminants from the stabilized matrix
  • 49.
    Solidification and StabilizationGeneral binding and sorbent materials: Cement Pozzolans Lime Silicates Organically Modified Clays
  • 50.
  • 51.
    High Temperature ThermalDesorption HTTD is a technology in which wastes are heated to 320 to 560 o C Produce final contaminant concentration level below 5 mg/kg
  • 52.
    Incinerator Structure tohouse the furnace Tipping floor where the Hazardous Waste is disposed Storage pit to store the Hazardous Waste delivered Charging system Furnace Air pollution control Ash handling system
  • 53.
    HWTC Control Philosophy Provide a Supervisory Control and Data Acquisition (SCADA). The SCADA system will provide two levels of control: Level 1 control operates equipment directly and bypasses all interlocks. Level 2 is initiated directly by computer programming. Level 2 controls, operates equipment and processes remotely.
  • 54.
  • 55.
    Environmental Monitoring Air Quality Groundwater Quality Surface Water Quality Dust and Noise
  • 56.
    Environmental Monitoring Selection of the parameters of concern Sampling methodology Quality assurance /quality control plan
  • 57.
    Project Approach Task1: Review of Existing Data Task 2: Discussion with Project Authority Task 3: Development and Finalization of HWTF Design Task 4: Prepare Final Design Drawings and Design Basis Memorandum
  • 58.
    Project Approach (cont.)Task 5: Design of Liquid Hazardous Waste Treatment Facility Task 6: Class I and II Landfills Design Task 7: Land Framing Facility Design Task 8: Solidification and Stabilization Facility Design
  • 59.
    Project Approach (cont.)Task 9: HWTC Construction Task 10: Facility Commissioning and Operation Task 11: Facility Handing Over
  • 60.
    Conclusions Key toproper design of HWTC is system flexibility to adjust to hazardous waste quantities and properties over time Enforcement of environmental law and regulations
  • 61.
    Leachate Treatment UsingWetlands Department of Environmental Engineering Beijing University of Chemical Technology December 2003
  • 62.
    Wetlands Wetland isdefine as land having the water table at, near or above the land surface or which is saturated for long enough period to promote wetland or aquatic processes as indicated by hydric soils, hydrophilic vegetation, and various kinds of biological activity which are adapted to the wet environment.
  • 63.
    Treatment Mechanisms ina Wetland System
  • 64.
    Type of Engineeredwetlands Constructed wetland systems are classified into two general types: Horizontal Flow System (HFS) Surface Flow (SF) Sub-surface Flow (SSF) Vertical Flow System (VFS).
  • 65.
  • 66.
  • 67.
  • 68.
  • 69.
    Field Monitoring Monitoring wells Pond #1 Pond #2 Peat Filter SW-1 SW-4 SW-3 SW-2 D B A C FSW-1 FSW-2 FSW-3 W-2 W-1 MW-4 MW-1 MW-2 MW-5 MW-3 Manhole Pump
  • 70.
  • 71.
    Boron adsorption wasdirectly related to organic content Peat filter was effective in treating landfill leachate The adsorption capacity of the peat can be significantly enhanced by lime addition Conclusions