Pilot Study On Advanced Treatment Of Tailrace In Chlor-alkali Industry Effluent Treatmemt Station By BAF

Chlorine-Alkali Chemical Industry is one kind of high water consumption trade. It is essential to delve into the advanced treatment technology of wastewater reuse for the realization of the sustainable development of society and environment.The present research takes Anhui Chloro Alkali Chemical Group Co.ltd as the subject to carry out the pilot-scale experiment on secondary effluent of the sewage treatment station in this enterprise group. The test adopts Biological Aerated Filter (BAF) and biological contact oxidation, with combination mode of parallel connection. Based on the microbe acclimation and biofilm colonization, the exiperiment inspects the infection of the ratio of gas and water, temperature, pH, hydraulic load, organic load and ammonic nitrogen load to the effluent quality. What's more, the corresponding BAF dynamic model is set up, and the comparison with the advanced treatment of contact oxidation is also analyzed in this thesis.The result of the experiment shows as following:(1) The COD removal efficiency is around 32% when influent COD concentration is at 79.48-131.27 mg/L, the ratio of gas and water is (3~5):1 and the hydraulic load in the range of 1.14-2.27 m/h.(2) When the ratio of gas and water is 5:1, and the hydraulic load changes from 0.57 m/h to 1.53 m/h, the ammonic nitrogen removal efficiency matains at 20%.(3) When the ratio of gas and water is 5:1, and the organic load changes from 1.40 kg COD/(m3·d)to 2.30 kg COD/(m3·d), the COD removal efficiency is around 32%; when the organic load is between 0.87 kg COD/(m3·d)to 1.62 kg COD/(m3·d), the ammonic nitrogen removal efficiency is around 20%.(4) On the condition that the hydraulic load is 1.53 m/h, the ratio of gas and water is 5:1, and the ammonic nitrogen load is under 0.51 kgNH3-N/(m3·d), the removal effect of ammonia nitrogen is better in the reactor.In general, temperature and pH are of little importance in the removal efficiency of COD, but of tremendous importance in ammonic nitrogen removal; contact oxidation has certain removal efficiency for COD, but not as good as BAF technology.The reaction kinetics of the COD degradation in BAF can be simulated with first order exponential decay model.According to Monod equation, the experiment simulates the kinetics test and achives the kinetics equation.