| The study of the thesis focused on In-Situ biocarrier capping technology to remedy sediment in the reservoirs. Zeolite, ceramic, and light porous carriers are choosed. They are inoculated couple of nitrification bacteria and denitrification bacteria to make biocarrierss, and then put the biocarriers on the surface of the contaminated sediment in order to restrain and eliminate endogenesis pollution in the sediment through the mechanism of the nitrification and denitrification. The aims of the study is to find out the optimal biocarrier to control endogenesis pollution. We investigated the adsorption kinetics of zeolite and ceramic, and the effect of diameter of zeolite, dosage of zeolite on remediation to explore the mechanism of nitrogen removal. The results will provide theoretical support to In-Situ remediation sediment in reservoirs. The main results and conclusions are as follows.(1) In adsorption kinetics of zeolite experiment, the results show that zeolite can quickly adsorb ammonia, and adsorption equilibrium appear in 6-9hours. In the initial stages of adsorption, the concentration of ammonia decreases from 79.48mg/L to 23.5mg/L, and the adsorption rate is 0.47mg/(L-min), then down to 0.09mg/(L-min). In the initial reaction, ammonia concentration decrease sharply and the adsorption ammonia rate of zeolite is very fast. As time goes on, the rate of adsorption reaction decrease. The adsorption reaction rate of 1～2mm zeolite is 1.125 times of that of 2-4mm zeolite, and is 1.5 times of that of 4-8mm zeolite.(2) The experiment of adsorption ammonia with zeolite and ceramic were carried out. Which inocluted combined the nitrification bacteria WGX15 and WGX18, denitrifiation bacteria HF3 and HF7 respectively. The results show that zeolite is the best biocarrier of adsorption ammonia. The removal efficiency of ammonia depended on the mass of zeolite, and increase with zeolite mass increasing.That is to say, the biological removal efficiency is 30.56%, when the mass of zeolite is 1g, while the biological removal efficiency is 100%, when the mass of zeolite is 5g. In contrast, the mass of removed ammonia is not so much in bio-ceramic system. Under application of 5g ceramic condition the biological removal efficiency is 39.9%.(3) In the experiment of finding out the optimal biocarrier to control endogenesis pollution, the results show that zeolite, ceramic and light porous biocarriers have the capacity of removing NH4+-N and TN. We observed that the removal efficiency of NH4+-N and TN respectively is 89.6% and 84.8% in bio-zeolite system, and the corresponding date is 65.1% and 59% in bio-ceramic system. The removal efficiency of NH4+-N and TN is 35.6% and 37.8% in bio-light porous system. So, bio-zeolite is the best carrier, and the bio-ceramic is better. Light porous fillers is the worst.(4) The experiment was carried out to investigate the effect of zeolite diameter on remedying the contaminated sediment. 1～2mm,2～4mm,4-8mm of zeolite were used and carried out under inoculation or non-inoculation conditions. We observed that under inoculation condition the removal efficiency of TN is 74.05%,85.24% and 78.99%, and the removal efficiency of NH4+-N is 80%,97.92% and 89.48%. Moreover, under the non-inoculation condition the removal efficiency of TN is 88.93%,82.81% and 82.54%, and the removal efficiency of NH4+-N is 94.41%, 87.21% and 91.71%. The results mentioned above show that the TN removal is independent on the diameter of zeolite.(5) The experiment was carried out to explore the effect of zeolite dose on remediation of sediment. The zeolite dose is 160g,190g,220g and 250g in this study. The results show that the removal efficiency of TN and NH4+-N is 83.15% and 100%, when the zeolite dose is 250g. The dose of zeolite is more, and the surface area is greater, and the attached nitrifying bacteria and denitrifying bacteria is more. So removal TN is better.(6) We tested two kinds of contaminated sediment using in-situ bio-zeolite capping technology. One is taken from man-made lake of Tang Paradise, another is a lake of Yangzhou. The results show that the removal efficiency of TN is 84.77% and 92.25%, while the removal efficiency of NH4+-N is 89.59% and 100%. These results show that In-Situ biocarrier capping is a effective technique to remedy contaminated sediment.
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