Advanced nitrogen removal of sulfur autotrophic denitrification under low nitrogen concentration
Sulfur autotrophic denitrification reactor was constructed to explore the advanced nitrogen re-moval of secondary effluent water of sewage treatment plant and limiting nitrogen removal of tail water.The study results showed that,under the condition that the mass concentration of DO was lower than 0.5 mg/L,the HRT was 15 min,the mass concentration of TN of the secondary effluent water could be steadily reduced from about 10 mg/L to less than 5 mg/L,and the effluent TN concentration could meet the requirement of grade A in local standard of DB5301/T 43-2020 Emission limits for main water pollutants from urban sewage treatment plants of Kunming city.Under the condition that the mass concentration of DO was lower than 0.5 mg/L,the HRT was 20 min,the mass concentration of TN in the tail water steadily decreased from about 6 mg/L to below 1 mg/L,the TN concentration in the effluent water could meet the ClassⅢ water standard in GB 3838-2002 Environmental quality standards for surface water.The microbial community structure in the reactor was analyzed by high-throughput sequencing,and the results showed that the dominant surfur autotrophic denitrifying bacteria at genus level were Thiobacillus and Sulfurimonas.
autotrophic denitrificationadvanced nitrogen removallimiting nitrogen removalHRTmicro-bial community structure