Research On Transformation Pattern Of Ammonia Nitrogen In Laboratory Simulating Semi-aerobic Landfill

Through the laboratory simulated test on semi-aerobic landfill, this thesis discusses the degradation of nitrogenous waste, reveals the degradation mechanism of waste in semi-aerobic landfill, provides theoretic basis and technical support for the deep research and engineering application of semi-aerobic landfill and offers ideas for the reconstruction of anaerobic landfill.The experiment results show that processes of ammonia nitrogen degradation in leachate of semi-aerobic landfill are devided into three stages: initial adjustment stage, transition stage and stabilization stage. Concentration of ammonia nitrogen increases rapidly in the initial adjustment stage while decreases rapidly in the transition stage, and the speed of decrease is higher than that in stabilization stage. The change treads of total nitrogen and nitrate nitrogen in leachate was similar to that of ammonia nitrogen. The increase of the value of pH which is caused by alkalinity produced by denitrification results in an accumulation in nitrite nitrogen in the initial stage.The semi-aerobic landfill can eliminate the pollution of nitrogen in the landfill by means of its self-disposal function in a shorter period within the laboratory simulated conditions. This supplies an important idea and way for solution to the problems of high concentration of ammonia nitrogen being difficult to treat in leachate in the middle and final stages. Waste density can decrease the oxygen content carried by waste, change the water content, which may lead to increase of the anaerobic area and decrease of the aerobic area in semi-aerobic landfill, thus affect the speed of degradation and prolong the stabilizing time of semi-aerobic landfill. The influence on ammonia degradation of leachate is parabola relationship instead of simple linearity. A model is constructed by for its ammonia nitrogen's degradation in leachate, the time degradates and meet the discharge standard is estimated at 439 days and the way of elimination of ammonia nitrogen is proposed at anaerobic landfill.This thesis is a good attempt in semi-aerobic landfill. The experiment results under middling scale experiment shed some light in the future operation, administration and design of semi-aerobic landfill, and contribute a lot to the removal of ammonia nitrogen in anaerobic landfill.