| Based on the previous research results from the municipal sewage treatment plant and sewage pumping station, H2S, NH3,VOCs and stench concentration were chosen to be monitored by continuously quantitative mearsuring before and after treatment by deodorant biotrickling filter system, Catalytic activated carbon tower deodorant systems and plasma deodorant system respectively. Three deodorant mechanisms which affected the deodorant efficient were discussed. At the same time a survey about the main odor sources emited from coarse screen, grit chamber, concentrated tank and dewatering workshop of sewage treatment plant and the stench emited from workshop, factory sector of two sewage pumping stations was conducted.The following conclusions and understanding were made.1. The survey and research on the stench source of sewage treatment plant and sewage pumping stations.The sewage treatment plant survey results showed that: (1) the monitoring of the stench of the main sewage plant odor sources indicated that H2S was emited around 0～22 mg/m3, which was significantly higher than those of NH3. So H2S was the most important indicators for controlling the stench. However, at sludge treatment sections there were many types of volatile organic compounds (VOCs), and toluene, sulfide and ethanethiol which were the strong odor substances. Therefore, in the sludge treatment area, in addition to H2S, the volatile organic compounds (VOCs) removal was also very important. (2) H2S and NH3 emited from coarse screen, grit chamber, concentrated tank and dewatering workshop showed significant seasonal variation, the emissions concentration of both were higher in summer and autumn season,but they were the opposite case in winter and spring. (3) for the H2S and NH3 generated from sewage, the emissions concentration increasing as the increase of the water temperature. When the water temperature was lower than 18℃and 21.6℃, the emissions concentrations of H2S and NH3 from coarse screen, grit chamber and sludge thickener were closed to 0. (4) rainfall could reduce the stench emited from sewage treatment plant, the dilution of pollutants and the increase of dissolved oxygen concentration and the decrease of water temperature might be the main reasons why the concentrations were low in the rainy days.The investigations of xi hao chong sewage pumping station revealed that: H2S concentration in xi hao chong sewage pumping station workplace was 0.06～0.62 mg/m3, NH3 concentration was around 0.01～0.06mg/m3, and the stench concentration was 68～175 (OU/m3). The concentration of NH3 in the edge of factory met the air emission standards, while the concentration of H2S and the stench concentration were beyond the standards.The investigations of dong hao chong sewage pumping station revealed that: H2S concentration in side dong hao chong sewage pumping station workplace was 0.01～0.05 mg/m3, NH3 was 0.03～0.12mg/m3, and the stench concentration was 41～68 (OU/m3). The concentration of H2S and NH3 in the edge of factory met the 2nd emission standards of municipal sewage treatment plant emissions GB18918-2002, but the stench unit still exceeded the standard.2. Analysis of the treatment efficiency and impact factors on the stench (H2S, NH3 and the stench concentration) treated by two biotrickling filter deodorant systems. The results showed that: (1)Biotrickling filter deodorant system①the concentration of H2S, NH3 and the stench concentration of the infficent air were 0.148～0.684 mg/m3, 0.107～0.652mg/m3 and 977～4121 (OU/m3) respectively. After the treatment by the biotrickling filter deodorant system, the effluent concentrations of H2S, NH3 and the stench concentration were 0.013～0.064 mg/m3, 0～0.081mg/m3 and 174～447(OU/m3) respectively, and their corresponding removal rates were 84.5 %, 75.2% and 82.2% above. (2)Biotrickling filter deodorant system②the concentration of H2S, NH3 and the stench concentration were 0.158～1.016 mg/m3, 0.206～0.782mg/m3 and 995～4121(OU/m3) respectively. After the treatment by the biotrickling filter deodorant system, the effluent concentration of H2S, NH3 and the stench concentration were 0.025～0.124 mg/m3 , 0.012～0.088mg/m3 and 174～447 (OU/m3) respectively, and their corresponding removal rates were 77.2 %, 73.1% and 82.2% above. (3)The treatment efficiency for H2S, NH3 and the stench concentration efficiency was decreased with lower temperatures, but the total removal efficiency of H2S, NH3 and the stench concentration in the system were still maintained at 84.5%, 75.2%, 82.2% and 77.2%, 73.1% ,70.8%.3. Analysis of the treatment efficiency and impact factors on the stench (H2S, NH3, the stench concentration) by the catalytic activated carbon deodorant system. The results showed that: (1) The average removal rates of H2S, NH3 and the stench concentration by the catalytic activated carbon deodorant system were 97.9%, 86.7% and 87.4% respectively. (2) There was no biofilm growth on the surface of catalyst of activated carbon. In catalytic activated carbon deodorant system, the role of deodorant was played partly by enhancing the ability of granular activated carbon with a major coal base-band in order to promote the oxidation, and partly was played by the adsorption of catalyst activated carbon, to achieve an effective removal of to the stench. (3)The main factors that affected catalytic-activated carbon deodorant system were gas residence time, pressure drop and the frequency for renew treatment.4. Analysis of the treatment efficiency and impact factors on the stench (H2S, NH3, the stench concentration) by the plasma deodorant system. The results showed that:(1)The concentration of H2S in the influent air was 0.456～2.877 mg/m3, with an average intake concentration of 1.268 mg/m3, after a plasma reactor's treatment, the concentration was 0.316～1.549 mg/m3 , with an average concentration of 0.660 mg/m3. It didn't meet the state emission standards over time, the concentration of NH3 in the sewage pumping station was low, the concentration of NH3 into the deodorant system was 0.046～0.256 mg/m3, with an average of 0.119 mg/m3, after the treatment by the system, the effluent was about 0.020～0.087 mg/m3 . The stench concentrations into the plasma deodorant system were between 1303 and 5495 (OU/m3), which were between 412 to 2137 (OU/m3) after treatment. (2) The main factors that affected the treatment efficiency of plasma deodorant system were voltage and frequency, gas residence time, polar electrode, the reactor cylinder shape and size.
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