Effect Of Nutrient Elements On Sulfur Autotrophic Denitrification Efficiency And Engineering Regulation Strategy

In this project,the experimental method of small-scale experiment-pilot verification was used to investigate the influence of nutrients on sulfur autotrophic denitrification efficiency and engineering regulation strategies.According to the operation of the small test reactor,the mechanism of nutrient elements affecting the nitrogen removal efficiency of the reactor was further explored.Therefore,it provides a theoretical basis for the design and operation of the pilot experiment,takes the sulfur autotrophic denitrification biological denitrification system to achieve deep denitrification as the overall goal,simulates the actual production process,carries out corresponding operation regulation of the filter,and explores the efficient denitrification operation mode of the reaction system,which has practical reference significance for the engineering application of sulfur autotrophic denitrification process.(1)The laboratory water distribution was used as the influent water to run the sulfur autotrophic small test reactor to investigate the influence of different nutrients on its nitrogen removal efficiency,which provided a theoretical basis for the design and regulation strategy of the pilot test.The test found that the denitrification efficiency of the small-test reactor had the concentration limitation of each nutrient element,and the denitrification effect of each reactor was changed by the concentration of ammonia nitrogen,phosphorus and inorganic carbon in the influent under the conditions of influent water temperature of 25°C and EBCT of 0.5h.After the concentration of ammonia nitrogen in the influent water is reduced to 0.2mg/L,the denitrification efficiency will be greatly limited,and the average nitrogen removal rate is 9.80mg/L.When the phosphorus concentration of the influent water was lower than 0.05mg/L,the denitrification rate was significantly reduced,the reactor collapsed rapidly,and the average nitrogen removal was 4.84mg/L.After the inorganic carbon concentration of the inorganic water drops to 100mg/L,the denitrification rate will gradually decrease,and the average nitrogen removal rate will decrease from 8.72mg/L to 2.4mg/L during the process of reducing from 100mg/L to20mg/L.Therefore,in practical applications,pay attention to the changes of various nutrients to ensure the stable and efficient operation of the reactor.(2)Based on the operation data of the pilot reactor,the econometric relationship between each nutrient element and the synthesis of denitrifying bacterial cells was calculated and analyzed,and the influence of each nutrient element on the sulfur autotrophic denitrification process was analyzed from the response mechanism of microorganisms to each nutrient element.Using the actual wastewater as influent,the effects of sulfur autotrophic denitrification and nitrogen removal were explored through the pilot reactor and the possibility of pilot experiment was explored,and then the pilot scale sulfur autotrophic denitrification filter was designed and built,and a set of operating strategies suitable for sulfur autotrophic denitrification and nitrogen removal filter under different water quality conditions were explored.Under this operation strategy,the total nitrogen removal load of pilot filter can reach0.63kg N/m~3/d,which meets the requirements of practical engineering and provides a reference for the application of sulfur autotrophic denitrification technology in practical engineering.