砾间接触氧化/水平潜流人工湿地净化微污染河道水

以微污染河道水为处理对象,研究了砾间接触氧化/水平潜流人工湿地复合工艺对水质的净化效果。经过26 d改变进水配比、曝气方式等的调控运行,成功启动复合工艺模拟装置,砾间接触氧化区(简称砾石区)的COD、NH4⁺-N去除率均稳定在75%左右,TN去除率在45%~60%。为进一步强化净化效果,探讨了砾石区水力停留时间(HRT)和砾石曝气区与非曝气区(O/A)分段进水配比对砾石区及后置潜流人工湿地出水水质的影响。当砾石区HRT为5 h时,砾石区对污染物的去除效果较好,COD、NH4⁺-N、TN平均去除率分别可达72%左右、75.28%、67.79%,人工湿地对三者的去除率分别为31%、43%、28%;当O/A区分段进水配比为1∶1时,对COD、NH4⁺-N的平均去除率较高,分别为77.39%和84.91%,分段进水配比为1∶2时,对TN的去除率最高,达到68.5%,人工湿地对TN的去除率为24.47%。因此,砾石区HRT为5 h为较佳参数,分段进水配比可根据进水污染状况灵活选择,研究结果可为实际工程应用提供理论支撑。     

UASB反应器处理活性黑KN-B废水的研究

采用UASB反应器处理活性黑KN—B废水,研究了水力停留时间（HRT）、碳源组成及浓度等因素对废水处理效果的影响,考察了反应器对该废水可生化性降解的作用。试验结果表明：反应器的最佳HRT为24h,当HRT小于24h时．废水的COD去除率显著降低,而BOD,的去除率不受影响,稳定在90％。在不同葡萄糖和蛋白胨的碳源组合下．碳源含量高于2000mg／L时,废水处理效果差别不大;而碳源含量过低,低于2000mg／L时,COD去除率将明显下降,不利于对废水的处理：而BOD;的去除率受进水碳源组成的影响较小。在试验的各种条件下,UASB反应器的活性污泥都能够有效处理500mg／L的高浓度活性黑KN—B废水,去除率稳定在90％以上。     

有机负荷对厌氧活性污泥发酵产氢系统的影响

采用连续流搅拌槽式反应器(CSTR),通过改变进水COD浓度与水力停留时间(HRT)2种方式,考察了有机负荷(OLR)对厌氧活性污泥发酵产氢系统产氢特性的影响.结果表明,在维持HRT 8 h、(35±1)℃不变的条件下,CSTR发酵产氢系统在进水COD浓度为6 000 mg/L(OLR为18 kg/(m3·d))时可获得较高的产氢量,平均为10.96 L/d;当进水COD浓度提高到8 000 mg/L(OLR为24 kg/(m3·d))时,系统产氢能力迅速下降.在维持进水COD浓度为6 000 mg/L、(35±1)℃不变的条件下,HRT为6 h(OLR为24 kg/(m3·d))时,CSTR发酵产氢系统的最大产氢量为16.2 L/d;当HRT降至4 h(OLR为36 kg/(m3·d))时,反应系统逐渐丧失了产氢能力.有机负荷过高,将引起了厌氧活性污泥发酵产氢系统内pH、碱度、氧化还原电位等生态条件的剧烈变化,不仅导致了厌氧活性污泥的微生物群落结构的改变,同时严重抑制了微生物的代谢活性.     

生活污水兼性生化影响因素分析

在常温条件下采用兼性生化处理生活污水,通过正交试验获取兼性生化降解有机物的影响因素.研究表明,COD去除率与HRT,M LSS和进水有机物浓度有关,M LSS的影响非常显著.过高或过低的M LSS、进水有机物浓度和HRT都会降低COD去除率.在本正交试验中得出最优水平:M LSS为5 500 m g/L,进水有机物浓度为260 m g/L,HRT为8 h,此时COD去除率可达72.5%.     

污水处理管锥形填充床特性研究与分析

填料是生物接触氧化反应器的核心部分,本文从传统填料的优缺点入手,分析了管锥形填料的结构和特性,并对管锥形填充床对污水的处理性能进行了试验验证。试验结果表明,针对模拟废水处理,负荷在2.3～8.0kgBOD5/m3.d范围内(比一般生物滤池负荷高10倍以上),都达到很高的处理效果;HRT为1h时,使污水的COD值由400mg/L降至37mg/L,去除率达92%;出水SS为3mg/L,大大降低二沉池的停留时间,节约投资。     

Natural attenuation and characterization of contaminants composition in landfill leachate under different disposing ages

Chemical Oxygen Demand (COD) composition in landfill leachate would vary as the disposal time extended. Leachates with different ages were collected from Laogang Refuse Landfill of Shanghai, the largest landfill in China with a placement scale of 7600 t refuse per day. To characterize COD composition in leachate, samples were size-fractioned into suspended fractions (> 0.45 μm), colloid fraction (0.45 μm < fraction < 1 K Da MW) and dissolved fractions (< 1 KDa MW) based on the molecular weight distribution. The fractions < 0.45 μm (including colloid fraction and dissolved fractions) in leachate were further divided into 6 fractions, i.e. hydrophobic bases (Ho-base), hydrophobic acids (Ho-acid), hydrophobic neutral (Ho-neutral), hydrophilic bases (Hi-base), hydrophilic acids (Hi-acid) and hydrophilic neutral (Hi-neutral). It was found that the ratio of TOC/TC in leachate decreased over time, indicating that the percentage of organic matters in leachate decreased as the disposal time extended. It was also observed that the hydrophobic fraction accounted to about 50% of the total matters presented in the fraction < 0.45 μm of all leachate samples. The main components in < 0.45  μm fraction were the Ho-acid, Hi-acid and Hi-base fractions. The percentage of Ho-acid in leachate decreased from 60.8% (2 a) to 43.2% (12 a). In addition, leachate with different ages was categorized into 3 phases according to the results of Principle component analysis (PCA). TOC/COD ranges of leachate in periods I, II and III were 40-54.6%, 16.9-41.3% and 10-38.9%, respectively, indicating that the COD contribution of non-carbon reduction substances increased over time in leachate. Hence, the corresponding landfill leachate treatment process should be modified according to the leachate characterization. The results obtained in this study might provide the important information for modeling, design, and operation of landfill leachate treatment systems.     

Optimization of hydrogen production from pretreated rice straw waste in a mesophilic up‐flow anaerobic staged reactor

This study was carried out to assess the efficiency of a mesophilic up‐flow anaerobic staged reactor for continuous H₂ production from pretreated rice straw waste. The reactor was operated at different hydraulic retention times (HRTs) of 20, 16, 12, 8 and 4 h. The organic loading rate and sludge residence time were kept constant at 30 g chemical oxygen demand (COD)/L/day, and 1.9 days, respectively. The results showed that increasing the HRT from 4 to 20 h increased the H₂ production from 0.4 ± 0.1 to 3.6 ± 0.3 L H₂/day, respectively. This corresponds to a H₂ yield of 2.1 ± 0.2 mol H₂/g COD_removed at an HRT of 20 h and 0.03 ± 0.002 mol H₂/g COD_removed at an HRT of 4 h. Likewise, carbohydrate and COD removal efficiency was strongly dependant on HRT. The removal efficiency decreased from 76.5 ± 3.4% to 40 ± 2.2% for carbohydrate and from 77.7 ± 4.3% to 12.2 ± 2.1% for COD when the HRT is reduced from 20 to 4 h, respectively. The addition of presettled sewage sludge to pretreated rice straw at a mixing ratio of 1:4 (v/v) increased the volumetric H₂ production from 3.6 ± 0.3 to 8.2 ± 2.5 L/day and the H₂ yield from 2.1 ± 0.2 to 2.8 ± 0.3 mol H₂/g COD_removed. Moreover, the removal efficiency of COD, volatile solids and carbohydrate was significantly improved. Copyright © 2013 John Wiley & Sons, Ltd.     

EGSB处理中药废水的效能及影响因素

采用厌氧膨胀颗粒床(EGSB)反应器处理中药废水,考察了进水COD浓度、停留时间、回流比对运行效能的影响.结果表明,EGSB对中药废水具有良好的处理效能,在温度为30℃、HRT=12 h、回流比=1、进水COD由2 000 mg/L逐渐提升至5 000 mg/L的条件下,对COD的平均去除率达94.2％;在HRT=9 h、进水COD=5 000 mg/L、回流比为1时,平均去除负荷达12.6kgCOD/(m3·d),平均产气率为0.353 m3CH4/kgCOD;在调整温度为20℃、回流比为2、进水COD为5 000 mg/L时,运行稳定后,对COD的平均去除率为93.4％,平均去除负荷为11.63 kgCOD/(m3·d),平均产气率为0.157 m3CH4/kgCOD,表明增加回流比可在一定程度上抵消温度给反应器带来的不利影响.     

淹没式复合型MBR处理城市生活污水的效能研究

为了缓解缺水压力，在传统膜生物反应器（CMBR）的基础上开发出了一种新型城市污水处理回用工艺——淹没式复合型膜生物反应器（SHMBR），并考察了对城市生活污水的处理效果。试验结果表明，SHMBR可以在CMBR的基础上进一步提高生物量，并明显改善了对有机物和NH4^＋-N的去除效果。试验中对TN、TP的去除效果没有提高，原因可能是生物膜的厚度不够，没有在生物膜内部形成厌氧微环境。另外，SHMBR的除磷效果没有增强还可能与生物膜的SRT较长以及聚磷菌主要生活在活性污泥中有关。     

压力曝气生物滤池处理生活污水的中试研究

为避免新兴城市小区、小城镇、度假村等分散污水的直接排放而污染环境,研制出一种小型生活污水处理设备,并以某污水厂的沉砂池出水为原水进行中试研究,考察了其处理效能.结果表明,这是一种经济实用的分散式处理⒌工艺,对生活污水中的污染物具有较好的去除效果,出水水质良好;该设备启动较快,当水温>20 ℃时自然挂膜大约需要28 d,可采用对氨氮和亚硝酸盐氮的去除效果达到稳定作为设备启动成功的判定标准;该工艺较适宜的进水COD负荷为5-30kg/(m3·d),进水SS浓度宜控制在80 mg/L以下,适宜的运行温度为15～30 oC,当温度<10℃时可通过延长水力停留时间来提高处理效果.