Bio-conversion of organic wastes for their recycling in agriculture: an overview of perspectives and prospects

Abstract

Largely accessible organic wastes can be turned into valuable compost product for raising crops organically on one hand, and get them disposed off safely at the other end. Straight use of organic wastes has tribulations like transportation and handling, wider C:N ratio, high application rates, nutrient overloading, weed seeds, pathogens, and metal toxicities. Composting bestows a tactic for coping high volumes of organic wastes in environmentally sound and desirable manners. Composted materials are remarkably regarded for their ability to improve soil health and plant growth, and suppress pathogens and plant diseases. Currently several composting systems have become available; ranging from a crude and slow windrows method, to the most speedy and computer monitored in-vessel system. Scientific investigations of this biological cum chemical process have reached to molecular level. Value addition of compost through beneficial microorganisms, mineral materials and fertilisers is also being considered. The nature and composition of materials put into composting is imperative for its quality rationale. On the whole, principles and processes governing composting are not so straightforward that ordinary enterprises could develop efficient composting facilities for the treatment of organic wastes. In this scenario, accessibility of comprehensive information to the scientific community as well as environmental protection agencies is imperative. This review article brings together the current information necessary for effective composting of organic wastes from different origins with diversified characteristics under various situations. It also covers the schematic description of well known composting systems, and various factors controlling the process.

Microbial Anaerobic Digestion (Bio-Digesters) as an Approach to the Decontamination of Animal Wastes in Pollution Control and the Generation of Renewable Energy

“…Windrow involves placing a mixture of organic waste materials into long, narrow piles on a composting pad which are turned frequently [3]. Piles were mixed with a bucket loader and were capped with manure/bedding to meet Vermont and National Organic Standards (NOS) Board regulations (www.ams.…”

“…The primary types of commercial composting methods are windrow, aerated static pile, and vermicomposting. Although vermiculture does not inherently include a thermophilic phase [3,4], material can be pre-composted through aerated static piles and windrow to remove substances toxic to earthworms, inactivate plant seeds and remove human and plant pathogens. Generally, we have a poor understanding of the biological dynamics that occur during the composting process and there are no current regulations or guidelines that define desirable microbiological properties of compost.…”

Vermicomposting with maize increases agricultural benefits by 304 %

“…The total quantities of organic matter and N, and available P and K were significantly higher in traditional compost than those in vermicompost (P≤0.05, Table 1). This might be because earthworms and microbes require carbon as energy source and nitrogen to build proteins (Ahmad et al 2007). Although carbon and nitrogen were consumed, plentiful additional earthworms were obtained (Table 2); simultaneously, the activities of earthworms convert the cattle manure into a finely divided, peat-like vermicompost, with higher porosity, aeration, drainage, water-holding capacity, and microbial activity being achieved (Edwards and Burrows 1988;Atiyeh et al 2001).…”

“…To solve such problems, more sustainable agricultural practices are urgently required. Compared with chemical agriculture, organic farming has been thoroughly proven as beneficial in maintaining both biodiversity and environmental sustainability (Ahmad et al 2007; Leite et al 2010). Organic farming has been gradually adopted by agriculturalists, particularly in developed countries (Rigby et al 2001;Lobley et al 2009), because of its higher economic and ecological benefits.…”

An Overview of Organic Waste in Composting

“…The performance of the composting process also will depend on the characteristics of the waste because a Corresponding author : aeslina@uthm.edu.my composting is only suitable for waste that is biodegradable [7]. There are many advantages that can arise from composting, including the reduction of volume, weight and water content of the waste as well as producing inactive pathogenic organisms [8,9].…”