Effects Of Sulfate And Salinity On Denitrification Performance Of Anaerobic Ammonia Oxidation In Flue Gas Denitrification Tailings In Thermal Power Plant

Compared with the traditional biological nitrification or denitrification technology, it is unnecessary for anaerobic ammonia oxidation technology to provide organic matter as electron donor. Saving operating cost, the anaerobic ammonia oxidation technology is of great value in practical research.Anaerobic ammonia oxidation sludge was taken from the Laboratory of Water Pollution Control in Qingdao University. The experimental conditions were 35±1℃,HRT for 20 hours and pH(7.5 ± 0.2). After cultivation of 25 days, Anaerobic Sequencing Batch Reactor(ASBR) was launched successfully reducing reddish sludge. The results showed that the ratio of removing nitrogen from ammonium and nitrite ion reached 98.14%, 98.14% respectively when the anaerobic ammonia oxidation was running stably.Ratio of removing nitrogen from ammonium, nitrite and nitrate ion while the anaerobic ammonia oxidation was running stably reached 1:( 1.29±0.02) :(0.25±0.02). The reactor running stably in recovery phase illustrated that anaerobic ammonia oxidation reaction was dominant. The MISS and VSS of the sludge are11.80 g/L and 8.85 g/L respectively. The activity of anaerobic ammonia oxidation sludge in the reactor was recovered.The effect that sulfate radical impacts on the properties of anaerobic ammonia technique of removal nitrogen was studied. By the mixed waste water to experiment, the concentration of SO42-was gradually increased from 500 mg/L to the highest, 6000 mg/L, at an average of gradient 1500 mg/L. Effect of SO42- in desulfurization waste water on anaerobic ammonia oxidation process could be evaluated by the speed change of removing nitrogen from ammonium, nitrite ion and total nitrogen.Experimental results showed that when the concentration of sulfate was below6000 mg/L under the low ratio of C/N waste water, anaerobic ammonia oxidation reactor was adaptive to this kind of water and showed good effect of denitrification for a long time of domestication. This means that the concentration of sulfate waste water would not have inhibitory effect on anaerobic ammonia oxidation reactor.The effect that salinity impacts on the performance of anaerobic ammonia technique of removal nitrogen was studied. By the mixed waste water to experiment, the concentration of Cl-was gradually increased from 1000 mg/L to the highest,10000 mg/L, at an average of gradient 2500 mg/L. Effect of Cl- in desulfurization waste water on anaerobic ammonia oxidation process could be evaluated by the speed change of removing nitrogen from ammonium, nitrite ion and total nitrogen.The experimental results showed that when the salinity was less than 3000 mg/L,the removal rate of ammonia nitrogen was more than 95%. When the salinity was more than 5000 mg/L, the removal rate of ammonia nitrogen fell slightly but still more than 90%. When the salinity was more than 7000 mg/L, the removal rate of ammonia nitrogen decreased significantly and less than 75%. However, the removal rate of ammonia nitrogen showed a rising trend for the prolonged domestication. This means that domestication time is the key to the efficiency of denitrification in the reactor under the high salt environment.