Study On The Campus Sewage Treatment With Three-phase Circulation Integrate Biological Fluidized Bed

Nowadays, there are more than forty millions college students live in campus in China which has huge population.How to treat the growing campus sewage emissions is a very important problem that should be solved. three-phase internal circulation fluidized bed reactor, based on activated sludge process and biofilm process,with lower power consumption and higher efficiency might be helpful to solve this problem.In this experimental research object, campus sewage from canteen in Lanzhou technology university western campus was treated with three-phase internal circulation fluidized bed reactor and plastic material BM2 carrier. There for the effect of treatment to campus sewage with three-phase internal circulation fluidized bed reactor could be test.The whole research object is consist of stage of membrane and stages of determination: in the stage of membrane, the three-phase internal circulation fluidized bed reactor had been running for 20 days with carrier and sewage in to stabilise the system. when biofilm carriers was formed and attaches securely to carrier surface, the system is successful; in the stage of determination, temperature,aeration, COD, PH, ammonia nitrogen, turbidity, sludge concentration and sludge loading were determinated when hydraulic retention time is 8, 12, 24 and 48 hours respectively.Experimental results :Under stable system condition,when HRT between 24 and48 hours, COD of effluent water is at 0mg/l ~ 60mg/l and COD removal rate is more than 91%.When HRT between 8 and 12 hours,COD of influent water is at 0mg/l ~500mg/l and effluent water is at 0mg/l ~ 60mg/l and ammonia of the effluent water is stabilizing at 1.5mg/l.Experimental results show that the three-phase internal circulation fluidized bed reactor is compact structure, low power consumption, high treatment efficiency. The effect of treatment with this reactor is well, conforming which that of national primes standard. When the COD of influent water under 30mg/l. When concentration of COD,temperature and HRT are strikingly different, the reactor system could maintain high COD removal rate in any stage. It means the three-phase internal circulation fluidized bed reactor has a stronger capacity of resisting impact load and a stable system, which could guarantee high quality of effluent sewage.