Solid & Hazardous Waste Management Lecture 3

Questions and Answers

What is the classification of waste that includes discarded electronic devices like computers and TVs?

E-waste

Which type of waste prevention involves designing products to reduce the amount of waste that will later need to be thrown away?

Incineration

Recycling

Composting

Source Reduction (correct)

Recycling involves recovering useful materials from trash to make new products.

True

___ involves collecting organic waste, such as food scraps and yard trimmings, and storing it under conditions designed to help it break down naturally.

<p>Composting</p> Signup and view all the answers

Match the hazardous waste properties with their descriptions:

<p>Ignitability = Create fires under certain conditions or are spontaneously combustible Corrosivity = Capable of corroding metal containers like storage tanks Reactivity = Unstable under normal conditions and can cause explosions or toxic fumes Toxicity = Harmful or fatal when ingested or absorbed</p> Signup and view all the answers

Study Notes

Waste Classification

Waste is any material that is not needed by the owner, producer, or processor.
Types of waste: domestic, factory/industrial, oil factory, e-waste, construction, agricultural, food processing, bio-medical, and nuclear waste.

Composition of Classified Wastes

Solid waste: vegetable waste, kitchen waste, household waste, etc.
E-waste: discarded electronic devices like computers, TVs, music systems, etc.
Liquid waste: water used for different industries like tanneries, distilleries, dairy industries, thermal power plants.
Plastic waste: plastic bags, bottles, buckets/containers, etc.
Metal waste: unused metal sheets, metal scraps, etc.
Nuclear waste: unused materials from nuclear power plants.

Solid Waste

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.

Municipal Solid Waste Sources

Sources: residential, commercial, institutional, industrial, construction, and demolition activities.

Municipal Solid Waste Management

RA 9003: Ecological Solid Waste Management Act of 2000.
Strategies: source reduction (waste prevention), recycling, composting.

Waste Management Hierarchy

Source reduction (waste prevention).
Recycling: recovery of useful materials, such as paper, glass, plastic, and metals, from the trash to use to make new products.
Composting: involves collecting organic waste, such as food scraps and yard trimmings, and storing it under conditions designed to help it break down naturally.

Disposal and Combustion of Municipal Solid Waste

Landfills: engineered areas where waste is placed into the land, with 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.

Open Dump

Unsanitary, draws pests and vermin, harmful runoff and leachates, toxic gases.
Still accounts for half of solid waste.

Sanitary Landfill

Characteristics: layer of compacted trash covered with a layer of earth once a day and a thicker layer when the site is full.
Impermeable barriers to stop the escape of leachates.
Gases produced by decomposing garbage need venting.
Avoid: swampy area/flood plains/coastal areas, fractures or porous rocks, high water table.
Prefer: clay layers, heads of gullies.

Monitoring of Sanitary Landfills

Gases: methane, ammonia, hydrogen sulfide.
Heavy Metals: lead, chromium in soil.
Soluble substances: chloride, nitrate, sulfate.
Surface Run-offs.
Vegetation: may pick up toxic substances.
Plant residue in soil.
Paper/plastics, etc. – blown by the wind.

Incineration

Solves space problem but produces toxic gases like dioxins, Cl, HCl, HCN, SO2.
High-temperature furnaces break down hazardous compounds but are expensive.
Heat generated can be recovered: waste to energy.

Hazardous Waste

Hazardous waste is a waste with properties that make it dangerous or potentially harmful to human health or the environment.
Properties: ignitability, corrosivity, reactivity, toxicity.
Major types: toxic organics, heavy metals, radioactive wastes.
Hazardous diamond and symbols: NFPA diamond, CLP, GHS.

Dealing with Hazardous Wastes

RA 6969: Toxic Substances and Hazardous and Nuclear Wastes Control Act of 1990.
Methods: physical (cementation, encapsulation), chemical (chem. stabilization/fixing), bioremediation, phytoremediation, plasma incineration.