Interaction and Competition Between Methanogens and Acetogens in Anaerobic System

• Main Authors: Michael SetiadiTanera, 陳威威
• Other Authors: Langmuir Whang
• Format: Others
• Language: en_US
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/6c65r4

碩士 === 國立成功大學 === 環境工程學系 === 106 === Nowadays, energy demand is one of the hottest issue that we have. Caused by human population exponential growth in last decades, energy is predicted would not enough for fulfilling human needs, but higher bio-waste. Anaerobic bacteria have ability to convert common bio-waste such as polysaccharide to make a methane gas which has a big energy storage. In this research, we focus on the last step of methane production anaerobic bacteria, which are methanogens and acetogens. We examine the effect of acetogens and methanogens inhibition in anaerobic system. We use 2-bromoethanesulfonate (BES) and ampicillin for doing inhibition on methanogens and acetogens, respectively. Batch culture has done in different initial condition to analyze their performance at 35oC temperature and on 120 rpm shaker. Results shows that 50 mM of BES can fully inhibit 5 mL of sludge in 150 mL working volume, meanwhile 300 ppm of ampicillin can inhibit acetogens. Moreover, from the result we can conclude that methanogens will produce methane gas when the hydrogen gas concentration inside the system is low. Hydrogenotrophic methanogens and acetoclastic methanogens will have better performance when each of them work separately. Thus, the higher acetate concentration will generate acetoclastic methanogens to increase the ratio between methane and carbon dioxide production. Acetoclastic methanogens and hydrogenotrophic methanogens has 48 hours and 72 hours of lag phase, respectively, before they produce methane gas. Nevertheless, Acetoclastic methanogens has higher rate than Hydrogenotrophic methanogens, but after around 2.5 mmol x carbon atom of substrate is exist, the Hydrogenotrophic methanogens has higher methane production rate.