Study On Purification Of Sulfur Gas With Bio-trickling Filter Used Microbial Inoculum

Sulfur gas is a kind of harmful industrial waste gas. It not only pollutes the environment, creates acid rain, but also will endanger people’s health. Nowadays, the technology of bio-trickling reactor for industrial waste gas is getting more and more attention featured by simpler control, lower energy consumption, no secondary pollution,higher treatment efficiency, etc.This research focused on the improvement of the bio-trickling filter on the basis of related research in and out of the country. Bacteria was screened, domesticated and cultivated. Nutrient solution was replaced with the bacteria. This experiment studied the removing efficiency of improved bio-trickling reactor for sulfur dioxide and hydrogen sulfide, and the main factors of purification conditions are optimized.Bacteria from the samples were screened, domesticated and cultivated, bacteria could be got that can purify the sulfur gas. Bacteria were mixed and expand trained. The bio-film of the equipment was prepared from bacteria that had been screened and cultivated. The technics of biological desulfurization was studied using ceramsite as bacterium’s carrier and using bio-trickling filter as biological reactor. Bio-film was rapid fixed on ceramsite’s surface. After the bio-film was formed, quantitative sulfurous gas was bubbled into biological reactor, then purification effect of bio-trickling filter was studied for sulfur gas, and the conversion of the sulfur in the sulfur gas was explored, the main factors affecting of the purification efficiency also was studied.The results showed:(1) The bacteria was screened and cultivated, then was mixed and expand trained, and author could get bacteria that can purify the sulfur gas.(2)Usebacteria as circulating spray, bio-trickling filter could more efficiently purify sulfur gas,compared with water and nutrient solution.(3) During the purification of improved biological trickling filter for sulfide gas, purification efficiency and the p H reduced with the increase of system running time.(4) When the room temperature is 25 ℃, sulfur dioxide concentration in the intake gas was 1800 mg / m3, the gas residence time was 25 s,the spraying density was 1.65 m3/(m2·h), the p H was 5.5, the device for the removal of sulfur dioxide is the highest, it is 95%; When hydrogen sulfide concentration in the intake gas was 480 mg/m3, the gas residence time was 135 s, the spraying density was0.7 m3/(m2 · h), the p H was 5.5, the device for the removal of hydrogen sulfide is the highest, it is 85%. From above conclusion, sulfur gas concentration in the intake gas was less than 1700 mg/m3, the gas residence time was higher than 135 s, the spraying density was between 0.5m3/(m2·h) and 1.7 m3/(m2·h), the p H was 5.5, the device for the removal of sulfur gas is the higher.