The Study On Improved Technology Of Smoke Simultaneously Desulfurization And Denitrification By Double Tandem Biological Filter

The development of industrialization has gradually increased the demand for fossil fuels such as coal.The flue gas emitted from the combustion of fossil fuel contains a large amount of sulfur dioxide and nitrogen oxide gas,and this is the major factor in the formation of acid rain in most parts of the world.The biological flue gas desulfurization and denitrification technology attracts the attention of many scholars because of its advantages of less investment,low energy consumption,and good effect.At present,some progresses and achievements have been made.In this project,the circulating fluid generated in the flue gas desulfurization and denitrification process is treated as wastewater into the wastewater desulfurization and denitrification process.The pollutants in the gas phase that have been transferred to the liquid phase are further removed.The effluent is injected into the circulation tank as a circulating fluid to participate in the purification of the exhaust gas by the biofilm packing tower.Establish a biogas-liquid phase treatment of SO₂ and NO_X systems in flue gas.The effects of spray volume,gas flow rate,inlet gas concentration of SO₂ and NOx,pH of liquid phase treatment equipment,COD,dissolved oxygen,hydraulic retention time,and addition amount of nutrient in circulating fluid on the process effect were investigated to determine the optimum process conditions.High-throughput sequencing technology and related statistical analysis methods are used to analyze and identify microbial strains and bacterial structures inside each reaction device in the process.Examine the condition of microbial complex flora.The main research results are as follows:?1?Under the optimum process conditions,in the biogas-liquid phase combined system SO₂ purification rate can reach 100%,NO_X purification rate can reach 83%,the sulfate removal rate in the HABR unit is approximately 55%.The nitrate removal rate in the BAF unit is approximately 75%.The optimum process conditions are:The total gas flow is 0.2m3/h;Desulfurization tower denitrification tower circulating liquid spray volume are 10L/h¹2L/h;SO₂ gas concentration is about 3000mg/m3 and NO_X gas concentration is about 2000mg/m3.BAF device pH=7,C/N=12,DO=3mg/L;HABR device pH=6,C/S=4;After two days of treatment of circulating fluid in the BAF unit,the effluent enters the lower tank of the denitrification tower circulating fluid,After the HABR device treated the circulating fluid for 4 days,the effluent was pumped into the lower tank of the desulfurization tower circulating fluid;Each change the circulating fluid for 2L;Every 10 days,the nutrient composition was added to the desulfurization tower denitrification tower,and the nutrient addition amount was reduced to 1/2.?2?When the purification efficiency of the gas-liquid phase combined flue gas system is stable,Extraction of domesticated microbial samples in gas phase and liquid phase devices with 16S rDNA gene amplification of samples.High-throughput sequencing was used to analyze the microbial population structure in the system.Detection of desulfobacterales,Desulfuromonaeles,Desulfobulbaceae,SRB2,Thiomicrospira,and Garciella related to biological desulphurization;The BS5 class,Draconibacteriaceae family,Vulcanibacillus,Anaerovorax genera related to biological denitrification were detected,and the dominant strains in the system were determined.