| Odor pollution is thought more and more by people recently, and it is becoming a problem that can not be endured. The design item of Qunli waste water plant in Harbin is invested by the country, in the area along Songhua river.The paper is completed when I practiced in China Northeast Municipal Engineering Design and Research Institute. The paper introduces the process of research and choice about the design project, and through analysing different ways and combination ways, in the end, we confirm a most ideal design scheme, the scheme will provide a basis for the project's construction.One source of the odor pollution is wastewater treatment plants. As sewage treatment technique developed, the number of wastewater treatment plants increases fast. During the whole process of the sewage treatment, odor would be produced everywhere. The odor is harmful for people's subsistence and production. The law about air pollution prevention in china prescribe that every party who let odor be into air must take action on preventing residential area from pollution. Treatment of odor from sewage plants is imperative under the situation.There is not a recognized way to estimate odor pollution, also there is not a design criterion all over the world. As a result, it is very useful to investigate and study to receive much data for perfect design project.At first, the number of the heavily polluted odor of Qunli waste water plant is 25600m3/h, this part of odor should be seriously treated, and the design tolerance of deodorization setting is made in 30000m3/h. Main components are ammonia, sulfureted hydrogen, mercaptan, thiophene, amine and so on. Sulfureted hydrogen contribute most mephitis to odor, and ammonia's mumber is the largest. At the same time, the light polluted odor's tolerance is 65000m3/h, this part odor will be treated through the chimney far away.Contraposing the characteristics of acid absorption,alkali absorption and neutral absorption, we chose the first one, and the absorbent is NaClO, NaClO is neutral, and has low volatility and causticity,high solubility in water. The solution is 20%, and the flow rate is between 0.2 and 1.0m/s. L/G is between 0.1and 1.0L/m3, the press loss is between 19.6and 196Pa, expected removal rates of NH3 and H2S are 90% and 20%.After absorption, the odor's main components are H2S and organic matters, and they should be treated continuously. Adsorption is a suitable method. In this project, the adsorbent is PAN·ACF, and the adsorber is circumgyrate mode. Layer of adsorbent is 350㎜, the area is 4.17㎡, the flow rate is 0.3m/s, the expected removal rate of H2S is 99.5%.In this project, we also design catalysis burn part. In the whole adsorption system, adsorption and desorption process continuously run. The odor from adsorber which is filled with PAN·ACF is put into desorption area, in this area, high temperature is attained to oxidation odor. The catalysis is expected platinum, though it is valuable.Adding fans and tubings, then put the odor from the adsorber into aerotion pools. With the metabolism of the activated sludge, the odor can be controled. The depth of aerotion is about 5m, and the expected removal rate of organic matters and H2S is 99.6%.In the design, odor produced from every unit is collected using collecting system, the fans put the odor into treatment unit through the pipes. The collecting system is inhalation mode.From the context above,"chemical absorption– active carbon fiber adsorption– catalytic oxidation– aeration activated sludge"is adopted to the treatment of odor from Qunli sewage plant in Harbin. It is a new and available united method. Because of the uncertainty of the odor's components and the seasons'changes, some other operations can be chosen when the project run.
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