Abstract:

For the purpose of reducing the ammonia nitrogen and the organic pollutant with high concentration in the landfill leachate, this text used combination treatment with lime coagulation, blow off and CO2 aeration to pretreat the landfill leachate in order to lessen the pollutant load to the biochemical treatment in the later stage. This text used single-factor experiment to discuss the impact of different factors, such as dosing quantity of CaO, aeration time, temperature and the ratio of gas and solid, on the removal efficiency of the ammonia nitrogen, COD and UV254. It also discussed the most efficient reaction condition of the comprehensive treatment effect by orthogonal experiment. The experiment also aerate with CO2 after the orthogonal experiment as to reduce the high pH and the concentration of Ca2+. The results of this experiment indicated that, the removal efficiency of ammonia nitrogen had direct correlativity with each factors. That of COD and UV254 had positive relationship with the dosing quantity of CaO. With the most efficient experiment condition of coagulation-blow off which obtained from the orthogonal experiment, the removal rate of the ammonia nitrogen, COD and UV254 could get 98.8%, 60.2%, 68.7% respectively. After the further aeration with CO2, the pH of the garbage percolate fall to 6.8 from 12.1. The removal rate of the concentration of Ca2+ was 70.3% and that of COD was 65.7%.