Aeration biofilter referred to as BAF, is the late 80s in Europe and the United States developed a new biofilm wastewater treatment process, in the early 90s have been greatly developed, the largest scale of several hundred thousand tons per day, and development can be off Nitrogen and phosphorus removal.
① one-time investment than the traditional method of 1/4; ② occupied area for the conventional process 1/10 ~ 1/5, running low 1/5; ③ water requirements suspended solids 50 ~ 60mg / L, Level of treatment, such as the use of hydrolysis of acidification pool; ④ fillers are mostly shale ceramsite, diameter 5mm, layer height 1.5 ~ 2m; ⑤ water down, gas up the reverse flow can not be a secondary sink.
Aeration biofilter compared with the ordinary activated sludge method, with a high organic load, small footprint (1% of the ordinary activated sludge method), less investment (saving 30%), will not produce sludge expansion, Oxygen transmission efficiency is high, the water quality is good, but it is more demanding on the water SS (generally require SS ≤ 100mg / L, the best SS ≤ 60mg / L), so the need for pretreatment of water. At the same time, its backwash water, head loss are larger.
Aeration biofilter as a set of biological oxidation and trapping suspended solids in one, saving the follow-up sedimentation tank (secondary settling tank), with a volume load, hydraulic load, short hydraulic retention time, the required infrastructure investment, water quality: Running low energy consumption, low operating costs.
Aeration biofilter has a wide range of applications, and it has a very good or even irreplaceable function in water depth treatment, micro-polluted source water treatment, refractory organic matter treatment, low temperature sewage nitrification, low temperature micro-polluted water treatment.
In the low-temperature sewage, Xining second sewage treatment plant due to the minimum winter water temperature of about 6 ℃, in order to solve the problem of nitrification, in the feasibility study report recommended aeration bio-filter + A2 / O treatment process.
In the new project of 40,000 cubic meters / ton of sewage treatment plant (BOT concession project) project, the first application in the domestic sewage treatment project and the success of its process for the hydrolysis + secondary aeration biofilter (CN Pool and N pool two), the project has been put into operation.
In the treatment of refractory organic matter, Qingdao Beer (Xuzhou Jinbo) Co., Ltd. wastewater treatment project, and then the hydrolysis of acidification + aeration biofilter treatment process, from the operation point of view, the selection process is to meet the requirements.
In the water reuse, the Dalian Malan River sewage treatment plant project, using the French profit at least A3D + BIOFOR process technology, water quality to three standards, daily sewage treatment 120,000 tons, of which 40,000 tons of water back For urban greening, construction, industry and so on.
Shanxi Linfen water reuse project, the secondary treatment of water as a water source, in order to solve its ammonia nitrogen index, the project uses aeration biofilter as a pretreatment unit.
In the domestic, pig farm manure sewage treatment works, printing and dyeing wastewater treatment works, casing processing wastewater treatment works, starch wastewater treatment projects have applied.