Factors Affect Biological Remediation of Petroleum Contaminated Soils

• Main Authors: Shih-Ming Lin, 林仕明
• Other Authors: Shan-Shin Ton
• Format: Others
• Language: zh-TW
• Published: 1999
• Online Access: http://ndltd.ncl.edu.tw/handle/73064766060966120556

碩士 === 逢甲大學 === 土木及水利工程研究所 === 87 === Oil Spill to pollute the environment has been worried by scientists continuously. By chemical or physical treatments, the pollutants may effectively be removed. But the environment will be hurt again at the same time. Comparatively, bioremediation has the advantage of natural character, less expense and without any adverse effects to the environment. It obviously has great potential in the future. Bioremediation of enzyme-adding has been used in this experiment. By adding enzyme to the contaminated soil, we observed the capability of hydrocarbon-utilizing bacteria to decompose the total petroleum hydrocarbon (TPH) in the soil. Ozonation has also been applied to break down the complex hydrocarbon compounds into simple ones, to reduce the duration of bioremediation. Factors such as soil aeration, water contents, pH and heavy metals have been discussed to understand the impacts of microbial activities and TPH degradation rate on the soil. The experiment results show that, aeration of the soils can greatly enhance the growth of hydrocarbon-utilizing bacteria in the soil. This phenomenon is very assured in ozonation pretreatment. Aeration also helps in evaporation (especially for diesel) of TPH in the soil. The highest degree of degradation ups to 93%. Addition of enzyme is good for stimulating the regrowth of microbial in the soils as well, it is evidenced by the 100 times increased of bacteria counts in post-ozonation treatments. The degradation rate of hydrocarbon compounds was accelerated when the quantity of bacteria increased. The initial TPH of the soil has been reduced by ozonation from 51% to 80%. The addition of enzyme stimulated bacteria growth, accelerated biodegradation rate; therefore, shorten the long-winded time that bioremediation needed. It is concluded that properly controls the environmental factors and supply adequate materials for the growth of bacteria in the soil can degrade the pollutants completely. The application of ozonation as the pretreatment process accelerates the degradation rate can further shorten the time of bioremediation.