02667cas|a2200241 i 450000500170000000800410001703500150005810000240007324500720009726000520016930000360022149000270025750001050028450200580038952016110044765000470205870000340210570000480213970000420218771000720222981000590230185600650236020260817162952.0230399s1993    th  uzm rtt  00|  a1eng d  a.b100891350 aTran Thi Hong Nhien10aApplication of the BIOSTYR process in domestic wastewater treatment  aBangkok :bAsian Institute of Technology,c1993  a107 leaves +e1 online resource1 aThesis ;vno. EV-93-31  aA thesis submitted in partial fulfillment of the requirement for the degree of Master of Engineering  aThesis (M.Eng.) - Asian Institute of Technology, 1993  aA biological aerated filter combines bacterial degradation of pollutant by fixed biomass with physical filtration in a single reactor. An organic removal process has been operated on an experimental basis at a pilot plant over five months at the AIT - Environmental Engineering Division Laboratory. The wastewater feed was modified AIT domestic wastewater. The process consists of a granular media bed, particularly of polystyrene (thus, named biostyr process) with a specific gravity of approximately 0.06. The cylindial reactor was 4 m high and 0.2 m diameter. Headloss measurement was studied as a function of wastewater temperature, velocity and time. Experiments were conducted at 30°C, 38°C, 45°C and 55°C with velocities of 2 m/h, 4 m/h, 6 m/h and 8 m/h respectively. At 38°C, filtration time range was 5.5-10 hours and over 84% of the soluble COD was removed at all velocities investigated. At 30°C, 75.8- 89.4% COD removal was noticed, 89.4% COD removal with the exception of 6 m/h velocity and 8.5 hour filtration time. At 45 °C, 77.1-87.9% of soluble COD was removed, in which 87.9% COD removal could be obtained at 2 m/h velocity with a filtration time of 40 hours. A decreasing gradient of biomass from bottom to top of the reactor was observed. 2- 5.8% of purified water was consumed for backwashing operation. The optimal suspended solids removal occurred at 30°C with 6 m/h velocity. At lower temperature, maximum suspended solid removal could be obtained. The results indicated that effluent SS could be less than 30 mg/L, that is secondary treatment effluent standard in Thailand. 0aSewagexPurificationxBiological treatment1 aVisvanathan, C.,eChairperson0 aChongrak Polprasert,eExamination Committee1 aFujii, Shigeo,eExamination committee2 aSwedish International Development Agency (SIDA),eScholarship donor2 aAsian Institute of Technology.tThesis ;vno. EV-93-31  3Full-Textuhttp://203.159.5.9/ait-thesis/detail.php?q=B16681