Research Of Treatment Of Excess Sludge And Operation Efficiency In Sludge Drying Reed Beds

Sludge drying reed bed is one of constructed wetland technology, composed of shallowbed body filler and phragmites. Purification of sewage and sludge in sludge drying reed bed isthe result of joint action with soil, plant and microbial filler. The filler surface and reed rootsgrow a lot of microorganism when reed bed is completed. Sewage flows through the bed,suspended substance being intercept by soil, filler and root barrier. Organic matter can beremoved through attached on the surface of the filler biofilm adsorption, assimilation anddissimilation.The technology has been studied for nearly30years in foreign countries, but it is stillrelatively rare in China. This paper introduces the dry reed wetland system, setting thecontrast test of ventilation and no ventilation,and the effluent quality of leachate infiltrationbeing studied.Experiments show that the ventilation promote plant to grow. The removal effect ofphosphorus, the second pool is the best and the first pool is the worst. COD of the three pondeffluent are still not meet the "urban sewage treatment plant pollutant discharge standard"(GB18918-2002), needing to continue to treat.The three pool water leachate ammonianitrogen removal situation positively, effect of ammonia nitrogen removal is the best in firstpool; the content of nitrate and nitrite are more than the residual sludge, the residual sludgecontent of nitrate and nitrite content are relatively low, presenting the phenomenon ofnegative removal.Comparing the water content sludge drying bed, planting reeds pool than not plantedreeds is slightly low, it is significant before September, respectively65.2%(No2),66.9%(No3) and65.9%(No1). pH value of the effluent value of leachates is similar with raw sludge,this shows that they have not special effects to pH value with changed structure of bed body.Effects of pH value, moisture content and temperature on the ammonia nitrogen and thecontent of polysaccharides have obvious correlation. Moisture content is closely related topolysaccharides. Nitrate is closely related to nitrite. Sludge reduction effect is obvious,specially phosphorus and COD removal.