Solid Waste & Hazardous Waste

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Solid Waste & Hazardous Waste

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  • 1. Solid Waste & Hazardous WasteHikmat Al SalimMarch 20123/9/2012 solid & Hazardous waste 1

2. Waste Classification Municipal waste Construction demolition debris Nonhazardous industrial waste Incineration ash Hazardous waste 3. RegulationsSolid waste is regulated under theResourceConservation and Recovery Act (RCRA).Classification of non-hazardous and hazardouswaste depends on the chemical constituents ofthe leachate . 4. A waste is classified as a hazardous if it has ahazardous characteristic listed below.1. Hazardous Characteristics: Ignitable Hazardous Waste (TRIC) A liquid waste which has a flash point of less than orequal to 140 degrees F (60 degrees C) as determinedby an approved test method. A non-liquid waste which, under standardconditions, is capable of causing a fire throughfriction, absorption of moisture or a spontaneouschemical change and when ignited, the waste burnsso vigorously and persistently that it creates a hazard. An ignitable compressed gas or oxidizer.March 20123/9/2012 solid & Hazardous waste 4 5. 2. Corrosive Hazardous Waste (TRIC) An aqueous waste with a pH of less than or equalto 2 or greater than or equal to 12.5 is consideredto be a corrosive hazardous waste. A liquid waste that corrodes steel at a minimumrate of .25 inch per year as determined by anapproved test method.March 20123/9/2012 solid & Hazardous waste 5 6. (TRIC)3. Reactive Hazardous Waste A solid waste that is normally unstable, reactsviolently with water, or generates toxic gaseswhen exposed to water or other materials.4. Toxic Hazardous Waste A waste that contains certain substancesdetermined to be harmful at or in excess of themaximum concentration. Some of thosesubstances include lead, arsenic, and mercury.March 20123/9/2012 solid & Hazardous waste 6 7. Nature of Waste Problem Moisture within and flowing on the waste generatesleachate Leachate takes the characteristics of the waste Thus leachate is very variable and is site-specific -there is no "typical" leachate Flows gravitationally downward into the leachatecollection system Enters groundwater unless a suitable barrier layer orsystem is providedMarch 20123/9/2012 solid & Hazardous waste 7 8. Outlines Waste management methods Landfill design and regulations Function and usage of geosynthetics in landfillsystems Durability of geosynthetics Future trend of landfill management 9. Source ReductionSource reduction involves reduction in thequantity or toxicity of materials during themanufacturing process via: Decrease the amount of unqualified products byimproving quality control Decrease the unit weight of the product byusing high quality material. 10. Combustion Combustion can reduce the volume of the solid wasteup to 90% at the same generate power. There are 140 combustion plants the US. Emission must meet the EPA Clean Air Act. Residual ash is hazardous material and should bedisposed accordingly. 11. Destruction of wastes by Combustion The method is suitable for: Gases Liquids Slurries Sludge wastes Solids Containerized Incineration destroys molecular structure, thusmolecules with more stable structures and strongerchemical bonds require longer residence timesand/or higher temperatures.March 20123/9/2012 solid & Hazardous waste 11 12. Incinerator operating conditions must be monitoredcontinuously. The following are some parametersaffecting the efficiency of burning: Combustion temperature Residence timeDegree of mixing Presence of excess air The type of incinerator required depends on thechemic and physical state of "waste" :March 20123/9/2012 solid & Hazardous waste 12 13. Liquid injection Any pumpable waste Converts liquid waste to gas prior to combustionKilns Used on solids, liquids, and gases Many different types (e.g., rotary kilns, cement kilns, limekilns,aggregate kilns).Calcination or sintering 1800oC and atmospheric pressure. Destroys organics; reduces the volume of inorganics Incinerator Performance must be monitored, thus:March 20123/9/2012 solid & Hazardous waste 13 14. Destruction and Removal Efficiency (DRE) must bedetermined. This done by "monitoring" organization.The higher the figure of DRE , the more efficient isthe incinerator. DRE of 99.99% for all principalorganic hazardous constituents (POHCs) isrequired. Example: Wastes containing dioxins and furansrequires 99.9999% DREMarch 20123/9/2012 solid & Hazardous waste 14 15. Incomplete combustion afterburners must be installedfor exhaust Combust the exhaust at higher temperature than thecombustion of primary waste stream. Example: dioxinand furan creation, more toxic than precursors 75 dioxin congeners; 135 furan congeners Incinerators usually produce particulates; thusparticulate controls are important. Particulates can beremoved by using bag-houses, and water scrubbers Control of acid formation is also important e.g. HCl fromcombustion of chlorinated organics. Acids corrodemetals and form "acid precipitates", and acid rain. .Congeners are toxic chemicals that are formed duringincineration. A member of the same kind, class, orgroupMarch 20123/9/2012 solid & Hazardous waste 15 16. Municipal Solid Waste DisposalINCINIRATIONMarch 20123/9/2012 solid & Hazardous waste 16 17. March 20123/9/2012 solid & Hazardous waste 17 18. Landfill Landfill implies disposal of waste in the ground. 70% of the waste is disposed in landfill and thepercentage has been gradually decreasing. The amount of waste actually increased due topopulation growth. 19. March 20123/9/2012 solid & Hazardous waste 19 20. March 20123/9/2012 solid & Hazardous waste 20 21. The Largest Landfill Staten Island, NY 3,000 acres 2.4 billion cubicfeet of waste 25 times of thegreat pyramid 22. Nature of Waste Problem Moisture within and flowing on the waste generatesleachate Leachate takes the characteristics of the waste Thus leachate is very variable and is site-specific - thereis no "typical" leachate Flows gravitationally downward into the leachatecollection system Enters groundwater unless a suitable barrier layer orsystem is provided 23. Hazardous Waste Definition Waste is listed in Appendix VIII of Title 40, Codeof Federal Regulations, Part 251. Waste is mixed with or derived from hazardouswaste. Waste is not identified as municipal waste. Waste possesses one of the followingcharacteristics: ignitable; corrosive; reactive and toxic. 24. Minimum Technology Guidance (MTG)for a Subtitle D LandfillSolid Waste150 mm300 mm600 mmFilter (or GT)Drain (or GN/GC)Clay @ 1x10-7 cm/secSoil SubgradeGT (opt.)GM*Compositeliner 25. MTG for a Subtitle C Landfill300 mm Drain (or GN)S-GM*Solid Waste150 mm300 mm900 mmFilter (or GT)Drain (or GN/GC)Clay @ 1x10-7 cm/sec(to highest groundwater level)P-GM*3.0 mCompositeliner 26. Landfill Covers(Non-hazardous landfill withoutGeosynthetic on the bottom liner system)Erosion LayerInfiltration Layer150 mm450 mm 27. Cover Layers Erosion Layer Earthen material is capable of sustaining nativeplant growth Infiltration Layer Permeability of this layer of soil should be lessthan or equal to the permeability of any bottomliner system or natural subsoils present, orpermeability less than 1x10-5 cm/sec whicheveris less 28. Landfill Cover System(Subtitle C & D, and Corp of Eng.)150 mm150 mm300 mm Drain (or GN)600 to900 mmTopsoilFilter (or GT)Clay @ 1x10-7 cm/secSolid WasteVaries(frost depth)Cover Soil300 mm Gas Vent (or GT)GM 29. Landfill Site Conforms with land use planning of the area Easy access to vehicles during the operation of thelandfill Adequate quantity of earth cover material that iseasily handled and compacted Landfill operation will not detrimentally impactsurrounding environment Large enough to hold community waste for some time 30. Geosyntheticsgeomembranes (GM)geosynthetic clay liners (GCL)geonets (GN)geotextiles (GT)geogrids (GG)geopipe (GP)geocomposites (GC) 31. Primary FunctionsType S R F D BGM - - - - YGCL - - - - YGN - - - Y -GT Y Y Y Y -GG - Y - - -GP - - - Y -GC Y Y Y Y YS = separation, R = reinforcement, F = filtrationD = drainage, B = barrier 32. Liner SystemGTGGGNGCLGMCCLGravel w/perforated pipe 33. Final Cover System 34. Solid Waste 35. Composite Barriers(Intimate Contact Issue)LeachateCCLClay Liner(by itself)LeachateCCLComposite Liner(with intimate contact)Does the GT compromise the compositeliner concept?Ans: Generally no...LeachateComposite Liner(GM + GCL)GCL 36. Composite Barriers(Theoretical Leakage)GM alone (hole area a)Composite liner (GM/CCL)Leachateks= 2Q C a gh BQ = 0.21 a0.1 h0.9 ks0.74(for good contact)Q = 1.15 a0.1 h0.9 ks0.74(for poor contact)Ref. Bonaparte, Giroud & Gross, GS 89) 37. Average Values of Leakage QuantitiesLife Cycle StageLeakage Rate (lphd)1 2 3403020100GMGM/CCLGM/GCLSandLeak Detection 38. Average Values of Leakage Quantities(contd)GM/CCLLife Cycle StageLeakage Rate (lphad)1 2 320151050GMGM/GCLGeonetLeak Detection 39. GeomembranesWidely Used Geomembranes Limited Used GeomembranesHigh density polyethylene(HDPE)Chlorosulfonatedpolyethylene (CSPE)Linear low densitypolyethylene (LLDPE)Ethylene interpolymer alloy(EIA)Flexible polypropylene(f-PP)Ethylene propylenetrimonomer (EPDM)Polyvinyl chloride-plasticized(PVC-p) 40. Compositions(approximate percentage)Type Resin CarbonBlackPlasticizer Anti-oxidantFillerHDPE 95-97 2-3 0 1-0.5 0LLDPE 95-97 2-3 0 1-0.5 0PVC-p 50-70 1-2 25-35 1-0.5 5-10fPP 95-97 2-3 0 1-0.5 0CSPE 40-60 5-40 0 1-0.5 5-15EPDM 25-30 20-40 0 1-0.5 20-40 41. Material Properties Mechanical property Density Melt flow Carbon black Plasticizers Antioxidant 42. Tensile Behavior Test method varies according to the resin type andstyle of the geomembrane. Each test method consists of unique shape ofspecimen and strain rate. Methods: HDPE, LLDPE and fPP ASTM D 638 Type IV PVC-p ASTM D 882 All reinforced geomembranes ASTM D 751 43. Design ConceptFSAllowable (Test) PropertyRequired (Desig