Abstract
The process of collection, transport, disposal, recycling, and monitoring of wastes is called waste management. The waste management is undertaken to recycle the wastes so as to reduce the ill effects of wastes on environment, health, and aesthetics. There are several kinds of wastes produced such as agricultural wastes, municipal wastes, industrial waste, mining waste. Some wastes are more hazardous such as medical wastes and nuclear wastes. Various techniques are used for the management of wastes which includes landfilling, incineration, anaerobic digestion, pyrolysis, plasma gasification, recycling, composting. Anaerobic digestion produces biofuel in the form of biogas. Plasma gasification results in the generation of electricity from wastes. Recycling of wastes involves the collection, sorting, and reprocessing of wastes into new products. Vermicomposting is the preferred form of composting as it results in the formation of vermicompost called black gold due to the presence of rich nutrients and growth promoting factors in it.
TopWaste Categories
There are several kinds of wastes produced; some are more hazardous such as medical wastes and nuclear wastes (British Medical Association, 1999). Wastes are released into air, water or land. Following are the main categories of wastes:
Solid Waste
Solid wastes are the wastes that are that are deposited at the site where they are produced. They are further categorized into following types:
Agricultural Waste
It includes sugarcane trash, rice straw, leaves of trees and crops, rotten vegetables, fruits and flowers, animal wastes such as cattle dung, pig manure, poultry manure etc. Most of the agricultural wastes are organic and hence can be converted to biofertilizer; vermicompost through vermicomposting (Venkatachalaiah, 1996; Garg et al., 2006; Muthukumaravel et al., 2008; Reddy et al., 2009; Ansari & Rajpersaud, 2012). Rest of the agricultural wastes can be incinerated or disposed in landfills. Air pollutants are released from incineration (Lai et al., 2009). Landfilling results in the emission of greenhouse gases such as carbon dioxide and methane which result in global climate change (Hurst et al., 2005).
Key Terms in this Chapter
Pyrolysis: It involves the thermal treatment of wastes materials in a sealed vessel under high temperature and pressure, with limited availability of oxygen to produce energy, activated carbon and other refined products.
Plasma Gasification: It involves the thermal treatment of waste materials in a sealed vessel under high temperature and pressure, with limited availability of oxygen to produce highly ionized and electrically charged syngas for the generation of electricity and heat.
Incineration: It includes burning of wastes in open areas or in an incinerator. Nowadays incineration in most of the developed countries is carried out in an incinerator that results in the conversion of waste to energy in the form of heat, electricity, or production of steam.
Waste Management: The process of collection, transport, disposal, recycling and monitoring of wastes is called as waste management.
Landfilling: In this method wastes are dumped in open land and wetlands.
Vermicomposting: The process of preparation of organic fertilizers with the use of earthworms is called as vermicomposting. It is the technique of breeding and raising earthworms for the production of vermicompost.