The Diversity of PHA-producing Bacteriain Activated Sludge Systems

• Main Authors: Bi-Ling Chen, 陳碧苓
• Other Authors: Sheng-Jie You
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/19258946153718921919

碩士 === 中原大學 === 土木工程研究所 === 95 === In Taiwan the use constantly of biological treatment processes is activated sludge, and a residual product from wastewater treatment process is wasteslugde haven become a burden that is harm to environment. The organic compound of specific bacteria’s cell among wasteslugde are called Polyhydroxyalkanoates (PHAs) that can be manufactured to become biodegradable plastic. PHA-producing bacteria in activated sludge are called Phosphate Accumulating Organisms (PAOs) that can be reached to removal of phosphorus from wastewater in Biological Phosphorus Removal system. Due to wasteslugde is a burden that is harm to environment, so the reduce of waste slugde and the source of energy are very important. Therefore, this study would analysis the diversity of PHA-producing bacteria in activated sludge of Nei Hu sewage treatment plant by using biotechnology of molecule, and confer the PHA content in bacterial , and find the optimization condition of accumulative PHA . Last, the feasibility study is about PHA-producing bacteria accumulate PHA by using the above liquid of wasteslugde anaerobic digestion. Experimental results have shown the number of PHA-producing bacteria in Nei Hu sewage treatment plant are about sixty-one by using PCR detective. Calculating the advantage baterial of PHA-producing bacteria in Nei Hu sewage treatment plant are Ralstonia sp. and Zoogloea ramigera which are around 25.9 and 11.9％ in all PHA-producing bacteria. In the diversity of phaC gene in Nei Hu sewage treatment plant’s sludge,the phylogenic tree is shown that the relation of in these bacteria is extremely wide. In the PHA content of PHA-producing bacteria, the results have shown the PHA content of several PHA-producing bacteria is 6 to 35％ of cell dry weight by using glucose as carbon source , among them Zoogloea ramigera is get highest PHA content , is around 35.08％ of cell dry weight.The next is alpha proteobacterium 5Z2111, the PHA content of alpha proteobacterium is around 19.38％ of cell dry weight. In optimization condition of PHA-producing bacteria’s PHA content, the results have shown that when pH of medium is controlled at 6 or 7 and cultivated temperature is controiied at 30℃, the greater part of PHA-producing bacteria are get higher PHA content by using glucose as carbon source. Besides the PHA content of PHA-producing bacteria is iower by using acetate as carbon source, is around 1 to 3％ of cell dry weight. In the PHA content of PHA-producing bacteria by using the above liquid of wasteslugde anaerobic digestion, the results have shown that PHA-producing bacteria use the excess carbon from the above liquid of anaerobic digestion, the PHA content of cell dry weight is about 1％.The result of PHA content which is lower in this part is the same with PHA content by using acetate as carbon source.