O_3—BAC工艺深度处理煤气化废水试验研究

采用O_3—BAC(臭氧—生物活性炭)工艺深度处理Lurgi煤气化废水二级生化出水,在臭氧接触塔水力停留时间为30min,臭氧投加量为9 mg/L,BAC柱反冲洗周期为10 d条件下,COD_(Cr)色度、氨氮和油类物质去除率分别为72.4%、79.7%、38.2%和92.5%。试验结果表明,虽然反冲洗时会对COD_(Cr)及氨氮的去除产生一定影响,但对色度和油类物质的去除影响不大,O_3—BAC工艺不但能够去除煤气化废水中残留的有机物,还能破坏显色有机物的生色基团,处理效果显著。     

粉末活牲炭回流技术去除原水中氨氮的研究

将含粉末活性炭(PAC)的沉淀池排泥水回流至原水进水处,延长PAC在系统中的停留时间,考察系统对氨氮、有机物和浊度的去除效果及去除氨氮的影响因素.结果表明,在温度为21～25℃,投炭量为50 mg/L条件下,系统第7～8天运行稳定,对氨氮、UV254和CODMn的去除率分别为40%、45%和60%左右,出水浊度在1 NTU左右,活性炭泥的生物量为130 nmolP/g左右.当活性炭泥回流比为6%,原水CODMn不超过10 mg/L,Ph为7～8,浊度不超过180 NTU时,对氨氮去除效果最好,为40%～50%,可应对原水氨氮浓度小于1 mg/L的情况.     

反冲洗对饮用水生物活性滤池生物量的影响

研究了反冲洗对生物活性滤池生物量的影响。试验结果表明 ,生物活性滤池中的微生物系统能够抵抗反冲洗时的水动力和氯灭活作用的共同冲击。反冲洗过程中 ,所损失生物量主要是以悬浮状态存在的 ,这些生物量在反冲洗后的过滤过程中会逐渐恢复 ,并能恢复到反冲洗前的水平。反冲洗对亚硝化细菌和硝化细菌的数量均造成了明显的影响     

生物预处理后续工艺中生物砂滤柱的性能研究

对黄浦江原水生物预处理后续工艺中的生物砂滤柱性能进行研究。在不同氨氮浓度的工况下,探讨了生物砂滤柱对氨氮、有机物等指标的去除,分析了生物砂滤柱的生物活性,同时总结了主要设备的设计运行参数。通过中试运行效果表明:在进水中平均氨氮浓度为1.73 mg/L,停留时间6.8 min下,氨氮平均去除率达到91.6%,同时CODMn和UV254的去除率分别为7.9%和7.5%。     

炭砂滤池去除有机物特性的研究

通过现场中试,研究活性炭—石英砂双层滤池(简称炭砂滤池)作为快滤池使用时对水中有机物的去除特性。结果表明:炭砂滤池代替普通砂滤池可有效去除水中的有机物,尤其对中低分子质量有机物去除效果较好。炭砂滤池依靠滤料截留、活性炭吸附和生物降解作用去除CODMn。试验期间炭砂滤池对CODMn去除稳定,平均去除率达50%。炭砂滤池主要依靠活性炭吸附去除UV254,稳定情况下对UV254的去除率在40%～50%。炭砂滤池对于有机物有较强的抗冲击负荷能力,滤速、反冲洗以及水力波动对其去除CODMn和UV254影响不大。     

生物活性滤池的特性研究

以南方某市水厂的沉淀池出水为对象 ,研究生物活性滤池的去除特性和机理。结果表明 :①生物活性滤池出水无异味 ,浊度低于 0 5NTU ,氨氮、亚硝酸盐氮去除率均达 90 %以上 ,CODMn后期去除率稳定在 2 0 %左右 ;②运行初期 ,活性滤料的物理吸附占主导地位。正常运行后 ,是活性滤料的吸附及其上生物膜的降解、粘附絮凝等共同发挥作用 ;③反冲洗有利于生物膜保持较高的活性和活性滤料吸附性能的发挥。     

低温条件下水解——AICS工艺在小城镇污水处理厂的应用研究

为了研究低温条件对水解—交替内循环活性污泥工艺(AICS)的影响,针对吉林省某市采用该工艺的污水处理厂冬季实际运行状况进行了监测分析.研究结果表明,低温对水解-AICS工艺的COD和氨氮去除效果影响较小,COD和氨氮的平均去除率分别达80％和70％以上,但低温限制了生物反硝化过程,冬季进水低负荷也限制了聚磷菌的好氧摄磷,使TN、TP的去除率下降;前端水解池的设置,有效提高了SCOD/TCOD,使溶解性有机物大大增加,有效改善了污水的可生化性.     

曝气生物滤池降解规律试验研究

采用实际分散型生活污水作为试验原水,对曝气生物滤池的降解规律进行了试验研究。结果表明,与传统的观点不同,曝气生物滤池在处理低浓度有机废水时并不发生严格的有机物与氨氮的分段去除现象,有机废水氨氮与有机质基本在同一区域内去除,滤料在10～40cm段的去除率增长速度最快,在70cm之后去除率的增长开始逐渐变缓。在进口段,由于有机质浓度高,供氧充足,有机质的去除率较高;由于异养菌和氨化菌的作用,氨氮浓度在进口段不但不减少,反有微小升高。     

齿轮型流化载体生物接触氧化池预处理微污染水源水研究

填料的选择对于生物接触氧化池的运行非常重要。以齿轮型流化生物载体为填料,对生物接触氧化池预处理微污染水源水进行了系统的中试研究。结果表明,以齿轮型流化生物载体为填料的生物接触氧化池在7天内启动成功,且生物量丰富。载体的流化状态好,氨氮处理效率高,气水比选择1∶2为宜。长期监测表明,生物接触氧化池对氨氮平均去除率为80.26%,对锰的去除率为34.50%,但对有机物去除不稳定。结合分子生物学研究表明,生物接触氧化池在预处理水源水时,载体表面菌属种群丰富,且功能菌属与其去除氨氮、锰和有机物的效能有直接关联,功能菌群数量越高,处理效果越好。     

投加氮源提高臭氧—生物活性炭工艺COD_(Mn)去除效果中试研究

采用中试研究投加氮源(NH4Cl)提高臭氧—生物活性炭工艺去除CODMn的效果。试验结果表明,投加一定量的氮源有利于去除有机物,而过量则无助于去除效果的提高。试验发现,NH4Cl的最佳投加量为0.75mg/L。在最佳投加量下,CODMn总去除率为59.5%,提高了5%左右;生物活性炭对CODMn去除率为36%,提高了6%。     

Experimental study on nitrification in a submerged aerated biofilter.

The aim of the present work was to evaluate the performance of a semi-pilot scale BAF in order to obtain a highly polished effluent in terms of removal of organic matter, suspended solids and ammonia and to observe the influence of temperature, pH and nitrite accumulation on the nitrification process. The ammonia removal efficiency during summer and winter and the nitrite accumulation in presence of free ammonia were observed. The biomass density was measured at different filter bed heights and the sludge production from the effluent of the backwashing water was evaluated. The results obtained were used to calibrate a mathematical model for the prediction of the ammonia removal profile in the filter bed and of biomass thickness.     

Biological aerated filtration of municipal wastewater using a low-cost filtration media.

The main objective of this research was to demonstrate that selected natural lava stones can be successfully used for low-cost aerobic biofiltration of municipal wastewater. To demonstrate the procedure a pilot filter was built using 6 mm lava stones as support material. The filter depth was 3.0 m. Provided with sampling ports at different depths analysis of the wastewater could be made for COD, TSS, ammonia and nitrates nitrogen, pH, temperature and Kjeldahl nitrogen. Backwashing was performed every 72 hours. Total and dissolved COD and TSS behaved similarly with the organic load: The highest removal rates were observed with the lowest organic load of 0.8 kgCOD/m3 d. These removal rates decreased to a minimum value at organic loading rates of 1.5 kgCOD/m3 d and then remained without noticeable changes to the highest value of 3.5 kgCOD/m3 d. The highest total and dissolved COD removal values were 81 and 84%, respectively. For TSS the best removal value was 95%. Up to 75% ammonia removal was achieved at the lowest organic load of 0.8 kgCOD/m3 d. Ammonia removal decreased to 36% with a higher organic load of 1.6 kgCOD/m3 d. The Mean Cellular Retention (MCRT) time varied from 1 to 6 days with an average of 3.2 days. This fact proves that the MCRT depends on the backwashing frequency more than of any other factor involved. The bed volume decreased in about 5% after 300 days of operation. Microscopic observations showed that the small stones were rounder after 300 days and that the volume losses were caused when the edges of the stones were cut by the abrasion caused by backwashing.     

农村污水生物泳动床处理技术研究

生物泳动床工艺是一种采用新型、高效生物填料的生物膜污水处理方法,是生物接触氧化工艺的改进。对农村污水具有很好的处理效果,通过试验发现填料挂膜速度快,一般只需1周左右的时间即可完成。生物填料膜没有集中脱落或闭塞现象、无需反冲洗。COD从250mg/L增到700mg/L,出水COD去除率仍然高达90%以上,出水平均氨氮小于5mg/L,出水平均TN小于20mg/L,TN去除率60%以上。通过调节运行参数和进水水质的试验研究,最终确定出生物泳动床高效低成本的工艺运行参数。     

Function of dynamic membrane in self-forming dynamic membrane coupled bioreactor.

The Self-Forming Dynamic Membrane Coupled Bioreactor (SFDMBR), which uses coarse pore-sized material to separate solid and liquid in bioreactors, has some advantages compared with MBR using micro-/ultra-filtration membranes, for example, low module cost and high flux. The cake layer and gel layer formed on the surface and in the pores of the material during filtration played an important role, called self-forming dynamic membrane (DM), which mainly consisted of activated sludge. In this study, the function of DM in pollutant removal was investigated. It was found that DM could remove some organic matter (12.6 mg L(-1) on average) and total nitrogen (3.01 mg L(-1) on average) in the supernatant. Colloids and organic nitrogen were partly removed by DM while DOC, ammonia nitrogen and nitrate nitrogen removal by DM varied from negative to positive, which resulted from the combination of various biological activities, e.g. nitrification, biological utilization and so on. DO concentration in DM decreased with the depth and reached zero at about 1.5-2.5 mm depth. The organic degradation activity and nitrification activity of the biomass suspended in the bioreactor were higher than those of the biomass in the cake layer, which might be caused by the low DO concentration and low organic pollutant content in DM.     

Ammonia oxidizing bacterial community composition and process performance in wastewater treatment plants under low temperature conditions

Nitrification can be difficult to maintain at wastewater treatment plants (WWTPs) during cold periods resulting in disrupted nitrogen removal. The aim of this study was to relate nitrification process performance to abundance and composition of the ammonia oxidizer communities in two closely located municipal WWTPs in Sweden during an eight month period covering seasonal changes and low temperature conditions. Both facilities showed lower NH(4)(+)-N removal efficiency and nitrification rates as temperature decreased. However, one of the plants had a more stable nitrification rate and higher ammonia removal efficiency throughout the entire period. The differences in performance was related to a shift in the composition of the bacterial ammonia oxidizing community from a Nitrosomonas oligotropha-dominated community to a mixed community including also Nitrosomonas ureae-like ammonia oxidizers. This was likely a response to differences in NH(4)(+)-N and organic loading.     

下向流生物滤池低温堵塞问题的分析与研究

深度处理中下向流生物滤池正常运行条件下,滤柱进水段由于污染物的降解。微生物大量积累,水头损失增长较快。尤其在低温下,由于水力条件、生物微环境、生物相改变以及微生物的自我保护,滤池更易发生气塞、堵塞,其运行周期比中温时降低近2/3,严重影响了净化效果。提出了局部反冲洗法解决膜滤池低温堵塞问题。局部反冲洗后,水头损失由60cm 降到30cm 左右。局部反冲洗在改善滤柱堵塞的同时,为自养亚硝化菌和硝化菌提供了更为稳定、适宜的微环境,使 NH_3-N 的去除率由15%增至50%以上;COD_(Cr)的去除效果因为生物活性的增加并未受到波动。局部反冲洗后,生物量和水头损失沿层积累率的最大值出现在滤柱下段。     

生物接触氧化流化床处理氨氮污水的实验研究

为了提高生物接触氧化流化床处理氨氮污水的脱氮效果,采用生物接触氧化流化床在自然温度下处理人工配制模拟生活污水实验的方法,研究了氨氮污水脱氮处理的可行性、方法与效果。实验结果表明:氨氮被氧化成硝酸可由两类独立的细菌分别催化完成;反应的适宜温度为20~35℃;亚硝酸菌的最适pH值为7~8.5之间,硝酸菌为6~7.5;亚硝酸菌和硝酸菌溶解氧质量浓度在0.5 mg/L以上才能取得较好的硝化效果。反应器内填料粒径在10 mm左右有利于提高氨氮的去除效率;间歇式进水方式使活性污泥具有良好的沉降性,可为氨氮的去除提供良好的环境条件。     

Ammonia removal in the catalytic wet air oxygen process of landfill leachates with Co/Bi catalyst.

Oxidation of ammonia in landfill leachates in the catalytic wet air oxidation (CWAO) process was investigated with Co/Bi catalyst. The characterization of the Co/Bi catalyst was carried out by the X-ray diffraction technique. Studies of ammonia removal from the landfill leachates by CWAO showed that Co/Bi catalyst exhibited higher activities for both total organic carbon (TOC) and ammonia with removal levels of 99% for TOC and 98% for ammonia, respectively. Results also indicated that large amounts of ammonia were produced during the elimination of nitrogenous organic compounds in the CWAO process and the further oxidation of ammonia gave off essentially N2 under 240 degrees C. When the system temperature reached above 240 degrees C, ammonia oxidation rate was much higher with nitrate dominating in the effluent; a very small amount of nitrite was observed in the reaction process, it possibly acts as the intermediate of nitrate ion and molecular nitrogen formation, showing that the system temperature had significant effects on the ammonia oxidation and reaction selectivity towards the production of molecular nitrogen or nitrate.