Saturday, March 2, 2019

Literature Review Methane

Methane retrieval from Landfills Utilization as a Potential Energy Source and affect on Reduction of Green House throttleses According to The Conference shape up of Canada, current Canadian municipal solid do in (MSW) generation levels ar approximately 30 one million million tonnes per year, with a rate of 894 kg per capita, 67 percent of which is landfilled. (Jones L. et al. 2002) salubrious landfills burry MSW under soil, sanctioning a mazy series of reactions to occur, where anaerobic microorganisms decompose a portion of the radical fraction of the exhaust producing methane and speed of clean-cut dioxide.Methane generation and emission from landfills argon guinea pigs of major interestingness due to methanes role in the nursery effect, migration of hazard dominance, health and asylum issues and energy applications. The objective of this literature review is to provide a elliptic relationship between MSW and landfill turgidityses (LFG), details of potential meth ods used for capturing methane as pose to emitting the gas as well as the benefits of doing. Rendering to information create verb exclusivelyy by D. R. Reinhart and T. G. Townsend (1998), MSW contains approximately 50 70 % of biodegradable genuine, such as food, paper, wood, and garden trimmings.Once MSW is deposited into a landfill, it undergoes a number of biological, physical and chemical changes. These changes atomic number 18 greatly dependent on site conditions, waste characteristics, temperature, quantity of oxygen, moisture content and other factors. (Nozhevinikova et al. 1993) The most heavy reactions occurring within the landfill are those involving the microbes which drive to consume the carbon in the organic material, in turn cause the decomposition and eventually stellar(a) to the evaluate of LFG.In sanitary landfills, the process of bury waste and regularly covering deposits with a low permeability material creates an internal anaerobic environment that favo rs methane producing bacteria since the presence of oxygen is lacking. Pathways leading to the production of methane and carbon dioxide from anaerobic digestion of organic fraction of solid waste are briefly described bellow 1) Decomposition of organic division- In this preliminary process, compounds of higher molecular stool (Lipids, proteins, nucleic acids etc. are modify into intermediate mass compounds qualification them much more suitable for the microorganisms as a source of energy and cell carbon 2) Conversion of de still matter to Organic Acid- In this phase, the liveing microorganisms convert the intermediate molecular mass compounds into lower molecular mass compounds such as compel organic acids. 3) Conversion of Acetic Acid to Methane Gas- During this stage, the microorganisms transform the acetic acid into methane (CH4) and carbon dioxide ( carbon dioxide) gasses. Cassia de Brito Galvao, T. and Pos, W. H. 2002) As the solid waste decomposes in landfills, the gas wh ich is emitted is composed of approximately 50 percent CH4 and 50 percent CO2, both of which are green house gasses (GHG) (Bingemer, H G. , Crutzen, P. J. 1987) With Landfilling being the primary source of tendency of MSW around the world, (Encyclopedia Britanica 2012) methane emissions from landfill represent the largest source of GHG emissions from the waste sector, contributing around 700 Mt CO2-e. coupled Nations purlieual course of studyme 2012) As recorded by Environment Canada (2010), similar trends exist nationally with emissions from Canadian landfills accounting for 20% of the hit national methane emissions. Information gathitherd in a thesis brisk by Palananthakumar, B. (1991) outlines the proportion of methane produced world wide from landfills, and finish be seen illustrated diagrammatically below in Figure 1. 0. Figure 1. 0 % of Methane Production Contributions widely distributed from Landfill Existing research leads to the confident statement that methane is a potent greenhouse gas.As summarized in a 2009 article from the municipal upstanding Waste, the Journal for municipal Solid Waste Professionals, In its Fourth Assessment Report (2007), The Intergovernmental plug-in on Climate transport (IPCC) concluded that, on a 100-year age frame, each molecule of methane has a global warming potential 25 times higher than that associated with a molecule of carbon dioxide. (Duffy, D. P. et al 2009) put off 1. 0 summarizes the enumerated global warming potential for the primary greenhouse gasses discussed. bow 1. Global Warming Potential (GWP) for a Given Time skyline Greenhouse Gas GWP20-yr (kg CO2-e GWP (IPCC 2007) 100-yr (kg CO2-e) GWP 500-yr (kg CO2-e) Carbon Dioxide (CO2) 1 1 1 Methane (CH4) 72 25 7. 6 (Forster, P. et al 2007) In the last decade, attention to methane emissions from landfills has braggy significantly with increased and ongoing awareness of global warming. The efforts of individual landfills as well as the nations as a whole are nearly monitored for the control of methane emissions.A trend has been observed that the magnitude of methane emission has been slightly decreasing, which is potentially due to the development of LFG to energy projects. Contrary to the negative perception associated with all greenhouse gasses, capturing this LFG can lead to beneficial outcomes. Generally, recovered methane either flares or is used as source of energy. The use of the gas as a source of energy is economical and environmentally friendly method to wince LFG emissions. There are three primary approaches for the utilization of LFG.They include 1) hold use of gas topical anaestheticly 2) Generation of electricity and distribution by dint of power grid 3) Processing and injection into a gas pipeline. (Palananthakumar, B. 1991) The captured LFG has the potential to provide a continuous source of energy and improve local air quality. In addition, using LFG can significantly concentrate GHG emission, making th e option of exploiting this alternative energy source a very executable option to MSW oversight. The United States environmental fortress mental representation has utilise this MSW management option and continues to encourage it.They have created a program that aims to help reduce methane emissions from landfills by assisting and encouraging the recovery and use of LFG as an energy resource. Since the programs inception, Landfill Methane Outreach Program (LMOP) has assisted 520 LFG energy projects in the United States reduce landfill CH4 emissions and avoid CO2 emissions by a combined 44 million metric lots of carbon equivalent. The reduction of methane emission through this program has slightly influenced the overall emission of LFG in USA.The success of LMOP can be reckoned by observing statistics from 2010 where reductions from all operational LFG energy projects were equivalent to Annual GHG emissions from 18. 5 million passenger vehicles. (United States Environmental Pr otection Agency 2012) A variety of technologies exist to generate electricity from collected methane including, internal combustion engines, gas turbines, and microturbines. Although there is a diversity of technologies, approximately eighty five percent of lively LFG electricity generation projects use internal combustion engines or turbines. United States Environmental Protection Agency 2012) How much energy can Municipal solid waste produce? is a common question among quick research. According to An Overview of Landfill Gas Energy in the United States published by U. S. Environmental Protection Agency Landfill Methane Outreach Program, one million tons of landfilled MSW can produce an electricity generation capacity of approximately 0. 8 MW. To farther quantify this value, allowing the magnitude of the electricity generation to be understood, Focus on Energy (2003) outlines that 0. 8MW would be drawn to power approximately 8 000 100w light bulbs.It can be concluded that LFG re covery wreaks benefits environmentally, socially and economically. LFG recovery, particularly methane, also makes an impact on the larger issue termed green house effect, as it is amongst the most cost effective and feasible measures to reduce greenhouse gas emissions. The recovered LFG can be directly or indirectly utilized to produce energy, which is a perpetually small, however a very important component of an integrated approach to the solid waste management apt(p) that the use of landfills continues to remain the predominant method of municipal solid waste disposal in most countries. Global Methane 2012) References Bingemer, H G. , Crutzen, P. J. (1987). The Production of Methane from Solid Wastes. Journal of Geophysical Research, 90(D2), 21812187. Cassia de Brito Galvao, T. and Pos, W. H. (2002) Landfill Biogas Management Case of Chilean Sanitary Landfills. Recovering Energy from Waste, 183-194. Conference Board of Canada. (2011). Municipal Waste Generation. How Canada P erforms, http//www. conferenceboard. ca/hcp/details/environment/municipal- waste-generation. aspx_ftnref3 (Sept. 28th, 2012) Duffy, D.. P et al (2009). Moving Up to the put across of the Landfill. Municipal Solid Waste Management. 19(2), 36-39. Encyclopedia Britanica (2012). Solid Waste Management. http//www. britannica. com/EBchecked/topic/553362/solid-wastemanagement /72390/Sanitary-landfill (Sept. 29th, 2012) Environment Canada (2010). Municipal Solid Waste and Greenhouse Gases. http//www. ec. gc. ca/gdd-mw/default. asp? lang=Enn=6F92E701-1 (Sept 29th, 2012) Focus On Energy (2003). Electricity rudiments for Renewable Energy Systems, Focus on Energy, Wisconsin. Forster, P. et al (2007) Changes in atmospherical Constituents and in Radiative Forcing. Climate Change 2007The Physical cognizance Basis. Cambridge University Press, Cambridge, United res publica and New York, NY, USA. Global Methane (2012). Basic Concepts of Integrated Solid Waste Management. internationalist Be st Practices Guide for LFGE Projects, Global Methane Initiative, U. S. Environmental Protection Agency, Washington, DC. Jones, L. et al. (2002). Environmental Indicators fifth Edition. Critical Issues Bulletin, The Fraser Institute Vancouver, BC Landfill Methane Outreach Program (2012). An Overview of Landfill Gas Energy in the United States U. S. Environmental Protection Agency, Washington, DC.Nozhevinikova, A. N. , et al. (1993). Microbiological Process in Landfills. Water Science Technology, 27(2), 243-252. Reinhart, D. R. , and Townsend, T. G. (1998). Landfill Bioreactor Design Operation, CRC Press LLC Boca Raton, FL, USA. Palananthakumar, B. (1991). Modeling of Methane Generation, Oxidation and Emission in Landfills. M. Eng. Thesis, Asiatic Institute of Technology School of Environment, Resources and Development, Bangkok, Thailand. United States Environmental Protection Agency (2012). Landfill Gas EnergyA Guide to Developing and Implementing Greenhouse Gas Reduction Progra ms. Local Government Climate and Energy Strategy Guides, U. S. Environmental Protection Agency, Washington, DC. United States Environmental Protection Agency (2011). Landfill Methane Outreach Program. Environmental Protection Agency, http//www. epa. gov/lmop/ faq/ lmop. html (Sept 29th, 2012) United Nations Environmental Programme (2012) Waste and Climate Change Global Trends and Strategy Framework. United Nations Environmental Programme Division of Technology, perseverance and Economics International Environmental Technology Centre, Osaka, Japan.

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