Introduction-to-Solid-Hazardous-Waste-Management.pdf

Lecture 3 Solid & Hazardous Waste Management 1  Waste Classification ❑ Any material which is not needed by the owner, producer or processor. Classification o Domestic waste o Factory/Industrial wa...

Lecture 3 Solid & Hazardous Waste Management 1  Waste Classification ❑ Any material which is not needed by the owner, producer or processor. Classification o Domestic waste o Factory/Industrial waste o Waste from oil factory o E-waste o Construction waste o Agricultural waste o Food processing waste o Bio-medical waste o Nuclear waste  Composition of Classified of Wastes o Solid waste - vegetable waste, kitchen waste, household waste etc. o E-waste - discarded electronic devices like computer, TV, music systems e o Liquid waste - water used for different industries eg tanneries, distilliries, dairy industries, thermal power plants o Plastic waste - plastic bags, bottles, buckets/containers etc. o Metal waste - unused metal sheet, metal scraps etc. o Nuclear waste - unused materials from nuclear power plants  Solid Waste* o Any garbage or refuse (Municipal Solid Waste) ⮚ Garbage – wet discard or kitchen waste (rubbish) ⮚ Trash – dry discard e.g. waste paper, dust etc ⮚ Other terms: refuse, litter o Sludge from a wastewater treatment plant, water supply treatment plant, or air pollution control facility o Other discarded material including solid, liquid, semi-solid, or contained gaseous material from industrial, commercial, mining, and agricultural operations, and from community activities Source: http://www.epa.gov/epaoswer/osw/basifact.htm#solidwaste Municipal Solid Waste Sources Source: http://ncrpb.nic.in/ 5  SW generation in Metro Manila ❑ 0.50 kg/capita/day* ❑ with population ~ 12M = 6000 tons of SW/day generated ❑ rely only on garbage collection; no composting, no burning *Bernardo, E.C. Annals of the NY Academy of Sciences. 1140(1): p. 420-424, 2008 6  Municipal Solid Waste Management RA 9003: Ecological Solid Waste Management Act of 2000 Source REDUCTION, or waste prevention, ⮚ designing products to reduce the amount of waste that will later need to be thrown away and also to make the resulting waste less toxic. 7  Municipal Solid Waste Management RECYCLING ⮚ recovery of useful materials, such as paper, glass, plastic, and metals, from the trash to use to make new products, reducing the amount of virgin raw materials needed. 8  Municipal Solid Waste Management COMPOSTING ⮚ involves collecting organic waste, such as food scraps and yard trimmings, and storing it under conditions designed to help it break down naturally. The resulting compost can then be used as a natural fertilizer. 9 Waste Management Disposal and Combustion of Municipal Solid Waste Landfills ⮚ engineered areas where waste is placed into the land. Landfills usually have liner systems and other safeguards to prevent polluting the groundwater. Energy Recovery from Waste ⮚ conversion of non-recyclable waste materials into useable heat, electricity, or fuel. Transfer Stations ⮚ facilities where municipal solid waste is unloaded from collection vehicles and briefly held while it is reloaded onto larger, long-distance transport vehicles for shipment to landfills or other treatment or disposal facilities. 11  Open Dump o Unsanitary, draws pests and vermin, harmful runoff and leachates, toxic gases o Still accounts for half of solid waste  Sanitary Landfill Characteristics o Layer of compacted trash covered with a layer of earth once a day and a thicker layer when the site is full o Require impermeable barriers to stop escape of leachates: can cause problem by overflow o Gases produced by decomposing garbage needs venting Sanitary Landfill Sanitary Landfill  When landfill is full, Topsoil layers of soil and clay seal in trash Electricity Sand generator Clay Methane storage building Leachate and compressor Garbage building treatment system Probes to detect methane Methane gas Pipes collect explosive leaks recovery well methane as used as fuel to generate electricity Leachate Compacted storage solid waste tank Garbage Groundwater Sand Leachate Leachate pumped monitoring pipes up to storage tank well Synthetic for safe disposal liner Leachate Sand Groundwater monitoring Clay and plastic lining well Clay to prevent leaks; pipes Subsoil collect leachate from bottom of landfill Sanitary Landfill  Sanitary Landfill o Avoid: ⮚Swampy area/ Flood plains /coastal areas ⮚Fractures or porous rocks ⮚High water table o Prefer: ⮚Clay layers ⮚Heads of gullies  Monitoring of Sanitary Landfills o Gases: Methane, Ammonia, Hydrogen sulfide o Heavy Metals: Lead, Chromium in soil o Soluble substances: chloride, nitrate, sulfate o Surface Run-offs o Vegetation: may pick up toxic substances o Plant residue in soil o Paper/plastics etc – blown by the wind Sanitary Landfills: Trade-offs  Incineration ❑ Solves space problem but: ⮚produces toxic gases like dioxins, Cl, HCl, HCN, SO2 ⮚High temp furnaces break down hazardous compounds but are expensive ($75 - $2K/ton) ⮚Heat generated can be recovered: % of waste burnt ▪ Japan 67%, Switzerland 80%, USA 6% Incineration o Air pollution vs o Waste to energy  Incineration ‘Waste to energy’ incinerator  Hazardous Waste Hazardous waste is a waste with properties that make it dangerous or potentially harmful to human health or the environment Properties o Ignitability - Ignitable wastes create fires under certain conditions or are spontaneously combustible, or have a flash point less than 60 °C (140 °F). o Corrosivity - Corrosive wastes are acids or bases (pH less than or equal to 2 or greater than or equal to 12.5) that are capable of corroding metal containers, such as storage tanks, drums, and barrels. o Reactivity - Reactive wastes are unstable under "normal" conditions. They can cause explosions, toxic fumes, gases, or vapors when mixed with water.  Properties of Hazardous Waste o Toxicity - Toxic wastes are harmful or fatal when ingested or absorbed (e.g., containing mercury, lead, etc.). When toxic wastes are disposed of on land, contaminated liquid may drain (leach) from the waste and pollute ground water. Toxicity is defined through a laboratory procedure called the Toxicity Characteristic Leaching Procedure (TCLP). o Major types: ⮚ Toxic Organics ⮚ Heavy Metals ⮚ Radioactive wastes – (separate in Ph)  Hazardous Diamond and Symbols NFPA diamond – National Fire Protection Association CLP - Classification Labelling and Packaging (EU) GHS – Globally Harmonized System of Class’n & Labeling of Chem Dealing with Hazardous Wastes RA 6969: Toxic Substances and Hazardous and Nuclear Wastes Control Act of 1990  Detoxifying and Removing Wastes Physical methods – cementation, encapsulation Chemical methods – chem. stabilization / fixing Bioremediation Phytoremediation Plasma incineration  Detoxifying and Removing Wastes Chemical methods – chem. stabilization / fixing  Detoxifying and Removing Wastes Bioremediation  Detoxifying and Removing Wastes Phytoremediation ex. Constructed wetland  Detoxifying and Removing Wastes Plasma incineration Hazardous Waste Landfill Deep-well Disposal Life Cycle of Waste Cradle to Grave 38 Life Cycle of Waste - Sustainable 39