Hazardous wastes treatment, storage, and disposal facilities

Abstract

Hazardous waste (HW) is defined as any residue or combination of residues that may be a potential hazard to humans or the environment. Wastes are classified as hazardous if they exhibit one or more properties of ignitability, corrosivity, reactivity, or toxicity. HW sources may be household, industrial, or biomedical. A waste is determined to be hazardous if it is specifically listed on one of four lists (the F, K, P, and U lists). Universal HWs are batteries, lamps, pesticides, mercury from thermometers, etc. Therefore, HW needs to be handled, stored, transported, treated, or disposed of carefully. A hazardous waste management strategy involves the following steps: (i) Waste minimization, (ii) detoxification and neutralization of waste by treatments, (iii) destruction of combustible waste by incineration, (iv) solidification of sludge and ash from steps 2 and 3, and (v) disposal of residues in landfills (waste minimization strategies include source reduction, recycling, and waste exchange). These steps help in resource conservation, economic efficiency, and environmental protection. The treatment methods are categorized as physical, chemical, and biological. Physical treatment involves a variety of separation techniques such as screening, sedimentation, centrifugation, flotation, adsorption, stripping, and reverse osmosis. Chemical treatments are meant for the absolute disintegration of hazardous waste into nontoxic forms. Chemical methods include neutralization, precipitation, oxidation, and reduction. In biological treatment methods, different types of microorganisms are used for the degradation of specific HW compounds. Some microbes found in soil and sewage sludge have been tested in the degradation of organic chemicals. Incineration has been used widely for disposal of hazardous wastes that cannot be reused or recycled and cannot be disposed of safely in a landfill because of excessive toxicity or risk of infectious transmission. This technique allows for significant volume reduction and varying magnitudes of toxicity reduction in the hazardous waste being treated. The disposal options include land disposal, underground disposal, deep well or underground injection, aqueous organic treatment, incineration, and landfill and surface impoundments. To evaluate economics and potential pollution risks, a proper disposal method should be adopted. To prevent environmental pollution from landfills, it is essential that the site be taken into account. Therefore, this chapter will deal with identifying and characterizing hazardous waste as well as its treatment and disposal. It will also deal with all the advanced technologies for waste disposal and critically discuss the best available technology (BAT) in the Indian context. © 2022 Elsevier Inc. All rights reserved.