空气曝气与纯氧曝气生物滤池应用于污水深度处理的研究

采用两种不同气源的曝气生物滤池对污水处理厂二级出水进行深度处理中试研究.结果表明,空气曝气和纯氧曝气生物滤池对COD_(Mn)的去除率相近,分别为30.5%和30.9%;以纯氧为气源的生物滤池硝化能力远强于空气曝气生物滤池,氨氮总去除率77.4%,出水氨氮为2.1～6.3 mg/L;纯氧曝气提高了滤池上部氨氮去除效果,维持滤池内溶解氧在6 mg/L以上,沿水流方向使pH逐渐下降.纯氧曝气生物滤池是污水深度处理中去除氨氮的有效工艺.     

膜生物反应器处理避孕药废水初探

采用A/O膜生物反应器处理高氨氮、高pH、难生物降解的避孕药废水。试验结果表明,此工艺处理该类废水可行,当水力停留时间为6h,系统对COD、氨氮和总氮的去除率分别为86%、73%和75%。好氧段的溶解氧维持在4mg/L可以同时实现对有机物和氮类的去除,对COD、氨氮和总氮去除率分别达到94%、63%和64%。通过控制A/O膜生物反应器的操作条件,可实现短程硝化和反硝化,提高总氮去除率。     

饮用水处理中不同滤料除氨氮效果及需氧量研究

对比研究了活性无烟煤、活性炭、石英砂以及无烟煤4种滤料过滤去除饮用水中氨氮的效果及其与需氧量的关系。试验结果表明,当氨氮低于2 mg/L时,4种滤料过滤都能够有效去除氨氮,水中溶解氧逐渐耗尽;当氨氮浓度高于2 mg/L时,4种滤料的去除率均有所下降,但相比石英砂和无烟煤而言,活性无烟煤和活性炭过滤能够更有效地去除氨氮。纯氧曝气能够将溶解氧浓度提高到25 mg/L,从而大幅度改善4种滤料对氨氮的去除效果;活性无烟煤和活性炭过滤可将大部分氨氮转化为硝酸盐,但石英砂和无烟煤过滤则会发生亚硝酸盐积累现象。在活性无烟煤和活性炭过滤去除氨氮过程中,氨氮去除量与溶解氧的平均比例为1∶4.25,略低于理论值。这种定量关系对于生物过滤去除氨氮工艺的设计和运行具有指导意义。     

沸石滤料生物滤池用于生活污水脱氮处理研究

为了去除生活污水中的氨氮,开发了沸石滤料生物滤池工艺,设置了13种工况对此生物滤池进行应用研究。试验结果表明,该工艺是一种经济实用的生活污水脱氮处理工艺。氨氮去除率稳定可以作为生物膜培养成功的标志。水力负荷的提高使氨氮的去除率明显下降,对CODCr去除影响则不大,最佳水力负荷为3m／h;同一工况下,生物降解稳定时,氨氮和CODCr去除容积负荷与其进水容积负荷呈线性相关,去除效果稳定;20-30℃是该工艺运行的最佳温度,低温下可适当延长停留时间;气水比为1:1即可使出水中溶解氧充足。     

UBAF预处理微污染水实验研究

利用上向流曝气生物滤池(UBAF)对微污染水预处理进行研究。研究表明:UBAF对微污染水的预处理有良好的效果;在水力停留时间为30min,气水比为1∶1,水温在20～30℃条件下,当进水氨氮为5.5～12mg/L时,UBAF对氨氮的去除率为80%～85%;对亚硝酸盐氮的去除率为80%左右;当进水CODMn的浓度为4.5～13.5mg/L时,UBAF对CODMn的去除率达到40%;提高流速,将水力停留时间由30min降至20min时,UBAF对氨氮的去除率由87.7%降至79.5%。     

以磷酸钙盐形式从内循环反应器中回收磷的初步研究

为探讨连续流内循环反应器以磷酸钙盐形式从污泥厌氧消化液中回收磷的工艺条件,考察了pH、Ca/P摩尔比、曝气强度和水力停留时间等因素对磷回收工艺过程的影响.结果表明,在污泥厌氧消化液总磷浓度86～108 mg/L、正磷浓度66～80 mg/L的条件下,保持反应体系pH9.0～9.5、Ca/P摩尔比2.0、水力停留时间45 min、曝气强度0.014 L/(L·min),内循环反应器磷的回收率接近90%,同时回收产品中磷的含量(以P2O5计)达到22.15%,可以作为磷肥生产原料.     

厌氧附着膜膨胀床反应器处理乳品废水的研究

研究厌氧附着膜膨胀床反应器中温处理乳品废水的运行工况。讨论在不同水力停留时间、容积负荷、pH值条件下对COD去除率的影响,并对进出水总氮及氨氮的变化情况进行研究。试验表明:厌氧附着膜膨胀床反应器处理乳品废水,在水力停留时间为8h、中温35℃条件下,COD去处率达到80%以上,对总氮的去除约为8%,出水有机氮的氨化率达70%以上,ρ(BOD)/ρ(COD)由进水的0 5提高到0 8以上。     

曝气生物滤地在污水回用中去除氨氮的试验研究

采用曝气生物滤地(BAF)工艺处理某污水处理厂模拟二级出水,研究了水力负荷及滤料层高度对NH_3-N去除效果的影响.试验结果表明,当进水NH_3-N≤25 mg/L时,平均NH_3-N去除率达到93.12%,出水NH_3-N可降至3 mg/L以下.当水力负荷为1.44 m~3/(m~2·h),HRT为1.8 h时,氨氮的去除效果最好,去除率达到95.32%,出水NH_3-N在1.5 mg/L以下.BAF对NH_3-N的去除作用主要发生在滤料的中上层.     

曝气炭砂滤池去除氨氮的生产性示范工程研究

通过运行炭层空气曝气活性炭-石英砂双层滤池(简称曝气炭砂滤池)生产性示范工程,并与无曝气炭砂滤池及砂滤池进行对比,研究了曝气炭砂滤池作为快滤池时对水中氨氮及亚硝酸盐氮的去除性能。结果表明,曝气炭砂滤池可将氨氮浓度低于2.5mg/L的进水处理至0.5mg/L以下,且进水氨氮低于1.5mg/L时不需曝气,其去除效果显著优于普通炭砂滤池和石英砂滤池;曝气炭砂滤池亦可有效去除亚硝酸盐氮。用曝气炭砂滤池替代石英砂滤池是水厂提升氨氮去除能力的一种可行的滤池改造方式。     

生产性生物陶粒滤池对微污染原水中氨氮的去除效果研究

作者在国内首次采用生产规模生物陶粒滤池处理受氨氮污染的原水,结果表明:生物处理对去除水中氨氮是有效的.同时得出溶解氧是影响氨氮去除率的主要因素,温度、流向及水力停留时间的影响相对较小.     

Achieving and maintaining of short-cut nitrification in a cyclic activated sludge system

A lab-scale Cyclic Activated Sludge Technology (CAST) system was operated more than 5 months to evaluate the effects of the operation mode on nitrogen removal performance and investigate a feasible method for achieving short-cut nitrification in the system. Results showed that nitrogen was removed by conventional biological nitrification and denitrification in traditional operation mode (fill/aeration 2 h, settle 1 h, decant 1 h), whereas short-cut nitrification and denitrification was the main nitrogen removal pathway in modified operation mode and the nitrogen removal performance was enhanced. Short-cut nitrification was successfully achieved in CAST system at 17 ± 1 °C by adjusting operation conditions and the average total nitrogen removal efficiency increased by 11.4% compared to traditional mode. It was assumed that low dissolved oxygen (<1.0 mg/L) limitation combined with free ammonia (0.28-0.34 mg/L) inhibition on nitrite-oxidizing bacteria caused nitrite accumulation in modified mode. During maintaining period of short-cut nitrification, preset aeration time enhanced ammonium-oxidizing bacteria dominance. It was also found that low DO could result in overgrowth of filamentous microorganisms and poor sludge settleability. The pH variation could provide effective information for controlling aeration duration in modified mode. However, no evident breakpoint appeared on pH and DO profiles in traditional mode.     

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。     

Low temperature biological phosphorus removal and partial nitrification in a pilot sequencing batch reactor system

Partial nitrification and biological phosphorus removal appear to hold promise of a cost-effective and sustainable biological nutrient removal process. Pilot sequencing batch reactors (SBRs) were operated under anaerobic/aerobic configuration for 8 months. It was found that biological phosphorus removal can be achieved in an SBR system, along with the partial nitrification process. Sufficient volatile fatty acids supply was the key for enhanced biological phosphorus removal. This experiment demonstrated that partial nitrification can be achieved even at low temperature with high dissolved oxygen (>3 mg/L) concentration. Shorter solid retention time (SRT) for nitrite oxidizing bacteria (NOB) than for ammonia oxidizing bacteria due to the nitrite substrate limitation at the beginning of the aeration cycle was the reason that caused NOB wash-out. Controlling SRT should be the strategy for an SBR operated in cold climate to achieve partial nitrification. It was also found that the aerobic phosphorus accumulating organisms' P-uptake was more sensitive to nitrite inhibition than the process of anaerobic P-release.     

过氧化氢处理河流着生刚毛藻的效果研究

以深圳市某河流为研究对象,分析了投加H2O2对刚毛藻生物量的控制效果及其对水体p H、溶解氧、氨氮和总磷的影响。结果表明:H2O2≥1.25 mol/L时能有效抑制刚毛藻生长,使藻类光合活性在10 min内从5.8降低到0,叶绿素浓度在30 min内从5.8 mg/L降低至0.2 mg/L。现场试验投加H2O2处理河流水体中刚毛藻14 d内,藻类生物量、光合活性和叶绿素浓度降幅均高于90%。加药1 h后,河流p H值由原来的9.21~9.74迅速降低至8.23~8.80,14 d内保持在9以下。河流溶解氧、氨氮、总磷和H2O2残留浓度在除藻过程中存在变化,但是1 d后会迅速恢复至加药前水平。投加H2O2是一种有效、无污染的应急去除河流着生刚毛藻的方法。     

Simulation of denitrification in groundwater from Chaohu Lake Catchment,China

The eutrophication of Chaohu Lake in China is mainly attributed to nitrate inflow from non-point sources in the lake catchment. In this study,biological nitrate reduction from groundwater in the Chaohu Lake Catchment was investigated under laboratory conditions in a continuous upflow reactor. Sodium acetate served as the carbon source and electron donor. Results showed that a carbon-to-nitrogen(C/N) molar ratio of 3:1 and hydraulic retention time(HRT) of 8 d could achieve the most rapid nitrate nitrogen(NO_3~--N) depletion(from 100 mg/L to 1 mg/L within120 h). This rate was confirmed when field groundwater was tested in the reactor, in which a NO_3~--N removal rate of 97.71% was achieved(from60.35 mg/L to 1.38 mg/L within 120 h). Different levels of the initial NO_3~--N concentration(30, 50, 70, and 100 mg/L) showed observable influence on the denitrification rates, with an overall average NO_3~--N removal efficiency of 98.25% at 120 h. Nitrite nitrogen(NO_2~--N)accumulated in the initial 12 h, and then kept decreasing, until it reached 0.0254 mg/L at 120 h. Compared with the initial value, there was a slight accumulation of 0.04 mg/L for the ammonia nitrogen(NH4-N) concentration in the effluent, which is, however, less than the limit value.These results can provide a reference for evaluating performance of denitrification in situ.     

深度处理维生素制药废水的中试研究

维生素制药废水经过初步生化处理后,出水水质无法满足要求,具有难降解、COD和氨氮浓度高的特点,针对这些特点,本文采用"强化复合曝气水解酸化→高效厌氧复合反应→流离生物接触氧化"连续工艺深度处理维生素制药废水,研究其可行性。处理规模为7.2 m3/d的中型试验结果表明:强化复合曝气水解酸化能使进水B/C值由0.33提高到0.48,提高下一步生化反应的处理效率,当进水CODCr的浓度为150～641 mg/L,氨氮浓度为6～115 mg/L时,平均去除率分别达到84.28%、93.8%,出水COD浓度小于50mg/L,氨氮浓度小于5 mg/L,出水水质能够达到《城镇污水处理厂污染物排放标准》GB18918-2002中的一级A指标,该连续工艺深度处理此类废水具有可行性和稳定性。     

污染河道水质强化脱氮生化工艺研究

应用生化工艺对河道污染水体进行修复是目前最经济的一条途径,但其面临的一个突出问题是在生物脱氮过程中可利用碳源不足,从而影响其处理效果。本研究采用分段进水生物接触氧化工艺来强化受污染水脱氮性能,与传统单点进水方式相比,两段进水对有机物和总氮去除率有显著提升,CODMn平均去除率从50.6%提升到66.3%;总氮平均去除率从31.4%提升到60.9%。沿程统计硝化细菌和反硝化细菌数量,硝化细菌主要集中在曝气区,数量为5.58×106,反硝化细菌主要集中在非曝气区的中后段,数量为6.49×105。同时检测沿程溶解氧和各氮素浓度,溶解氧浓度沿程降低,最后出水仅为0.2 mg/L;氨氮在曝气区转化为硝态氮,在非曝气区硝态氮还原成氮气,其结果进一步证实了硝化细菌和反硝化细菌的分布特征。     

数学模型在污水处理厂优化控制过程中的应用

通过小试结合模拟计算,分析了某污水处理厂现有运行存在的不足.试验表明,内回流比对提高脱氮率的作用是有限制条件的;对于溶解氧的控制,要根据系统硝化反应的需要来确定;缺氧区/总体积的比例是影响脱氮效果的一个关键因素,在保证硝化不受影响的前提下,增大缺氧区使反硝化进行得更充分,有助于提高系统的脱氮能力.通过模拟计算,对其工艺参数进行了优化组合,在不改变池容、不增加其他处理设施的情况下提出了优化方案,确定其最佳工艺控制参数为:缺氧区/总体积的比例为0.45,混合液内回流比为200%,好氧区溶解氧2 mg/L.调整后的出水总氮为21.77 mg/L,去除率较改造前提高了4%,出水氨氮浓度为1.16 mg/L,去除率提高了7.2 %.