Study On Vermibiofilter Disposing Sewage Technology

With the rapid growth of world economy, the impact of environmental pollution to water resources is more and more serious, Which leads to an urgent affair in water resources protection and water pollution control to the world and particularly to our country. The sewage treatment ratio of city is low, and makes severe consequence in our country. Traditional activated sludge process has some defects, and its cost of construction and running is too high. It directly influences the design and construction of sewage treatment plants and the improvement sewage treatment ratio in our country. And so, to develop new technology of disposing sewage is urgent in present. Vemibiofilter(VBF) ,an ecological new way to dispose sewage, was widely studied in France and Chile, and was applied in sewage and wastewater treatment of food industry or agriculture recently. In our country, however, the research on VBF is rarely reported. VBF has many merits as following:1) Be a natural ecological technology of disposing sewage, and have a easy fore disposal, little surplus sludge and no second pollution;2) Simple and short flow process, have not required primary sediment pond, secondary sediment pond and aeration pond, and low cost for construction;3) Have good effect, produce no odor;4) Management is easy and low cost;5) The scale is alterable and can be used in both a big city and a household;6) Can be applied in disposing sewage and wastewater of food industry or agriculture;Accordingly, under present economic strength, it is significant to research and exploit VBF. According to practical situation of our country, the program that we had been carrying out mainly focuses on studying VBF application in disposing sewage. From Aug. 8th, 2000 to Aug. 8th, 2001, the test of disposing sewage was carried out in Shanghai Longhua Sewage Treatment Plant and Shanghai Minhang District Sewage Treatment Plant.The result showed, at normal condition with 1.3～1.5m3/m2 d hydraulic load, the effluent of VBF could reach the secondary criterion of the national sewage discharged criterion (GB8978-1996). The removal ratio of CODcr,BOD5 and SS was above 80%, 85% and 90%, respectively. The effect of removing nitrogen(N) and phosphorus(P) was preferable. From June to Aug. 2002, we had made further the test of disposing synthesis wastewater at Shanghai Fengxian Sewage Plant Nanpai No.6 pumping station and acquired preliminary effect.