Anaerobic Digestion

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Anaerobic Digestion

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Overview

This essay studies the present status of the technology in Anaerobic Digestion in US. In the first section the general process of anaerobic digestion is described. Anaerobic Digestion is basically the decomposition of organic wastes in the absence of oxygen. A brief appraisal is provided about the current position of Anaerobic Digestion in the US energy Production. Then in the next section, the technological challenges of the Anaerobic Digestion are considered. The example of the usage of Anaerobic Digestion technology is discussed and the benefits of this technology. Also the demerits of this technology for the production of biogas are examined. Finally the current improvement in anaerobic digestion technologies in US is analyzed. Introduction

The Anaerobic Digestion is defined as the biodegradation of organic material that takes place in the absence of oxygen and in the presence of anaerobic microorganisms. The whole process proceeds in the series of metabolic reactions with the help of microorganisms. The organic material which is decomposed is generally the Municipal Solid Waste (MSW). This is the waste produced by the society excluding agriculture and industrial wastes. So, the waste that comes under MSW is commercial waste like from shops, markets, stores, hotels or residential waste from houses or institutional waste from hospitals, schools. The process of anaerobic Digestion completes in four stages namely Hydrolysis, Acidogenesis, Acetogeneis and Methanogenesis. In the first stage enzymes are secreted by microorganism and produced amino acids and glucose. Then these amino acids are converted into acetic acid by acetogenic bacteria. Finally a group of methanogenic bacteria convert CO2 , H2 and acetate to methane. The process is carried out in digester at temperature 300C…...

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