Combined Chemical and Biological Treatments of Landfill Leachate

• Main Authors: Kuo W. Cheng, 鄭國威
• Other Authors: Sheng H. Lin
• Format: Others
• Language: zh-TW
• Published: 2000
• Online Access: http://ndltd.ncl.edu.tw/handle/97202624612901755756

碩士 === 元智大學 === 化學工程研究所 === 88 === Leachate is a common liquid wastewater that is generated in a landfill site or municipal solid waste incinerator. Due to its complex characteristics and presence of many non-biodegradable substance, treatment of the landfill leachate has never been easy. The purpose of this work is to experimentally investigate several combined physical, chemical and biological methods for dealing with this particular type of wastewater. Chemical coagulation was adopted as a pretreatment of the raw landfill leachate. Test results have indicated that removal of suspended solids, color and some inorganic and/or organic compounds is quite good. The important operating variables of chemical coagulation included the initial pH, PAC/polymer ratio and the amount of PAC. Based on the test results, appropriate operating conditions of these variables were established for efficient operations. After chemical coagulation, the landfill leachate was treated by catalytic oxidation in a gas-induced reactor. In this chemical treatment, activated carbon fiber was employed, in conjunction with ozone, as a catalyst in oxidizing the recalcitrants in the wastewater. The test result of catalytic reaction was modeled using various kinetics, including first-order/multi-step, generalized and complex models. The models parameters were established by best fit of these models to the observed data. In the last of treatment train, sequencing batch reactor (SBR) was employed to further elevate the water quality of the landfill leachate to the discharge standards. The leachate after SBR treatment was clear with low COD below 100 ml/l. A Eckenfelder kinetics of completely mixed type was adopted to model the biological reaction of the SBR process and the parameters of the model were empirically identified.