With waste management highlighted as one of the major environment problems, local authorities have embarked on an intensive process of evaluating and identifying the most effective techniques and technologies available to curb the menace. Arguably, a drastic increase in volumes of waste and lack waste management awareness can be blamed for financial, and resource constraint witnessed in the overall waste management. The common problems for the local authorities are to identify and select an appropriate technology in waste management. Far from the conventional composting, landfilling and incineration, the authorities in collaboration with waste disposal organisations can fully implement the Anaerobic Digestion (AD), integrated bio-digester, Mechanical-Biological Treatment for unsorted organic waste and Biofuel Gasification as alternative systems in organic waste management.
Anaerobic Digestion has been in operation for a while but on a small scale by institutions such as SUEZ and Darling Ingredients. The proposed plan would entail large-scale disposal process that would see massive digestion tanks constructed where the large scale anaerobic fermentation will be taking place (Visvanathan, 2011). The methane collected from the process would be used to produce electricity that would be added to the national grid. Shea et al. (2011) argue that the central institution could set up digestion facilities to be used in transforming the organic waste into energy and organic fertiliser.
According to Korres, O’Kiely, Benzie and West (2013), Pyrolysis is another technique that could greatly help in disposing off organic waste from the city. Under this process, decomposition of the organic materials is quickened under intense heating in the absence of oxygen to produce hydrocarbon gasses. Further, these hydrocarbon gasses are heated to produce liquid fuel which can be used for industrial purposes. The solid byproducts of Pyrolysis process could then be sent back for recycling or to the landfills.
Mechanical-Biological Treatment is another approach that is widely recommended for unsorted waste disposal. The approach is invaluable in dealing with oversize waste items before subjecting them to the normal composting. The process involves manual sorting of the oversize organic materials before homogenising them into small elements (Organic Waste Program Planning & Logistics- Organic Waste Solutions, 2016). These materials are subjected to biological degradation by providing the favorable condition for their fast decomposition. The end products are high-end organic fertilisers that are sold to the farmers while the remaining small portions of waste are sent to the landfills (Mohan et al., 2006). Therefore, Mechanical-Biological Treatment in a way, would help in reducing the amount of waste sent to the landfills while developing a cheap source of organic fertiliser and mulch for farming (Korres, O’Kiely, Benzie and West, 2013). However, this approach needs an insightful examination to prevent the use of contaminated organic fertiliser that could eventually end up in food.
Biofuel gasification and production is another method utilisable as an alternative waste disposal system. It is an approach entailing biomass gasification to produce a gas similar to the LPG specifically as a transport fuel. During the process, the biomass being fed to a reactor and subjected to thermal chemical decomposition. The decomposition process yields a high-quality biome-thane which is combinable with the natural gas or used solely as fuel. This approach in highly recommended given the alarming rate at which the fossil fuels are destroying our environment or even at worse running out. For a sustainable and efficient waste management solution, the city should resort to this approach not only for cheap fossil-free fuel but also for environment protection.
Global Reach Internet Productions, I. 2016, Fast Pyrolysis Process – Avello Bioenergy, Avellobioenergy.com. Viewed 8 June 2016, <http://www.avellobioenergy.com/en/technology/fast_pyrolysis/>.
Korres, N., O’Kiely, P., Benzie, J. and West, J. 2013, Bioenergy production by anaerobic digestion : using agricultural biomass and organic wastes,.
Mohan, D., Pittman, C.U. and Steele, P.H., 2006, Pyrolysis of wood/biomass for bio-oil: a critical review. Energy & Fuels, 20(3), pp.848-889.
Shea T, Briggs J, Bharambe G, Clancy B, Gough D, 2011, Sydney Water’s New Biosolids Management Strategy Builds on strategic process modeling capacity. Proceedings of WEFTEC
Organic Waste Program Planning & Logistics- Organic Waste Solutions 2016, Organicwastesolutions.com. Viewed 8 June 2016, <http://organicwastesolutions.com/organic-waste-management-strategies.html>.
Visvanathan, C. 2011, Decentralized approach to treating the organic fraction of municipal solid waste with energy recovery by using inclined dry anaerobic digestion, Knovel.