低强度超声波提升厌氧污泥对重金属Cu（Ⅱ）极限浓度调控效果

以污泥基质降解速率(v_COD)、胞外聚合物(EPS)和酶活性(DHA)等变化为评价指标,探究了不同进水Cu(Ⅱ)浓度下低强度超声波提高厌氧污泥对重金属Cu(Ⅱ)耐受性影响的效应。结果表明,低强度超声波能够提高污泥微生物对Cu(Ⅱ)的耐受性。随着进水Cu(Ⅱ)浓度升高,超声组与对照组v_COD均下降,但超声组v_COD下降幅度更缓。超声组和对照组进水Cu(Ⅱ)浓度与污泥基质降解速率抑制百分比之间的关系拟合得到IC₅₀分别为94.62 mg/L和88.85 mg/L,表明低强度超声波能够提高厌氧污泥对Cu(Ⅱ)的抑制阈值。进水Cu(Ⅱ)浓度为1 mg/L时,超声组与对照组EPS含量略有提高,而后随着Cu(Ⅱ)浓度升高而逐渐降低,但超声组比对照组EPS含量更高,可能是低强度超声波通过促进污泥分泌更多的EPS降低了Cu(Ⅱ)的生物毒性。此外,超声组的DHA活性比对照组提高了3.95%～36.31%。因此,通过低强度超声波可以提高厌氧污泥对重金属Cu(Ⅱ)的耐受性,从而维持污水厌氧生物处理的稳定运行。     

ABR-人工湿地组合工艺处理生活污水

研究厌氧折流板反应器(ABR)与人工湿地(constructed wetland)的组合工艺处理低浓度生活污水的运行特点及效果.结果表明:ABR的最佳停留时间(HRT)为12 h,COD的平均去除率为76%;人工湿地的最佳HRT为4d.ABR-人工湿地组合工艺COD总去除率平均为89%,出水COD浓度为42～51 mg·L-1;对BOD5的总去除率达到95%,出水浓度低于11.2 mg·L-1;对SS的总去除率达到95%以上,出水SS浓度平均为9.1 mg·L-1;对氨氮有明显的去除效果,总去除率平均为66.8%,出水氨氮浓度低于15 mg·L-1.各项出水水质除氨氮外均满足GB18918-2002(城镇污水处理厂污染物排放标准>一级B标准.ABR-人工湿地组合工艺可作为农村生活污水的处理工艺推广使用.     

ABR反应器改进及常温启动的性能研究

为了加强处理系统的效果及稳定性,试验通过加大第1和第4隔室长度的方式,对传统ABR反应器做出了改进．在常温（18-32℃）下采用HRT逐步减小而有机负荷逐步提高的方式启动ABR系统,结果表明,启动第一阶段有机负荷保持在0．5-0．55kg／（m^3·d）,第二、三阶段负荷逐步增加,系统COD去除率高,当容积负荷为1．8kg／（m^3·d）时,COD去除率高达85．2％以上,改进后的反应器表现出了良好的抗冲击能力,说明常温下采用低负荷方式启动ABR是可行的．     

高铁酸钠处理某聚合物驱采油污水的反应条件的研究

以高铁酸钠为氧化剂,处理某聚合物驱采油污水,探讨在不同的添加量、pH值、反应时间及反应温度条件下,对污水中难降解聚合物PAM及COD的降解效果最优的反应条件.结果表明,高铁酸钠处理此聚合物驱采油污水的最佳反应条件为:添加浓度为80 g/m~3,pH值为3.5,反应时间为15 min,反应温度为45℃,此条件下的PAM去除率约93%以上,COD去除率约91%以上。     

好氧颗粒污泥的培养及处理低碳氮比废水效果

采用"搅拌-曝气-搅拌"间歇曝气运行模式,探索好氧颗粒污泥(AGS)在低碳氮比(1～6)废水中的形成规律及其对污染物的降解效果,旨在为低碳氮比污水的高效处理提供技术支持.当进水碳氮比为1～2.25时,接种污泥表现出明显的不适应,污泥量及颗粒化率增长缓慢,化学需氧量(COD)、总无机氮(TIN)及总磷(TP)的去除率较低...     

一体式A/O-MBR处理校园生活污水中试研究

采用一体式A/O膜生物反应器(MBR)处理低浓度校园生活污水,着重考察了处理效果、膜污染规律和稳定运行的条件.结果表明,COD、氨氮平均去除率为92.54%、98.10%;系统临界膜通量保持在0.13-0.14 m<'3>/(m<'2>·d);反应器最优运行工况为第1阶段后期.     

液态烃碱渣耦合离子液体废催化剂协同中和处置利用工艺研究

为实现液态烃碱渣和离子液体废催化剂的协同中和处置,采用化学沉淀—絮凝法工艺对液态烃碱渣进行预处理以去除硫化物与COD。系统考察了影响化学沉淀法的主要因素,选择硫酸铜为沉淀剂、在投加量为34 g/L、反应时间为20 min条件下,液态烃碱渣中硫化物去除率为96.88%,COD去除率为74.68%。进一步采用絮凝法处理反应体系,选择阳离子聚丙烯酰胺、在絮凝反应时间20 min、沉降时间90 min、投加量15 mg/L的条件下,液态烃碱渣中硫化物总去除率提升至97.13%,COD去除率达到81.67%。再将化学沉淀—絮凝法处理后的碱渣与离子液体水解液在20 ℃以体积比14︰100进行中和调控,反应后中和液中COD、硫化物、油类指标达到《污水综合排放标准》(GB 8978—1996)中污水三级排放标准,实现了液态烃碱渣与离子液体废催化剂的协同中和处置利用。     

超声与吹氩处理对钢液中夹杂物去除效果的对比研究

为提高钢的洁净度,减少钢中夹杂物含量,采用超声波工具头直接插入高温钢液进行处理的方法,对比研究了超声波处理和吹氩处理去除钢液中夹杂物的效果.结果表明:超声波单独处理可以减少钢液中Al2O3夹杂物,但去除率较低,约为4%～12%;随着超声处理时间的增加和超声波功率的减小,夹杂物去除率提高.吹氩单独处理时,钢液中夹杂物去除率较高,为29%～41%;随氩气流量的增加,夹杂物去除率呈升高的趋势.     

赤泥PAFC协同混凝印染污水试验研究

利用赤泥所含有的Fe、Al等具有净水作用的有效元素,得到Fe_20_3含量5.1%,Al_2O_3,含量6.5%,B65%的PAFC,结合印染污水的特性,通过对PAFC、PAM、PFS在印染污水处理中的混凝应用进行研究,发现PAFC对印染污水Zeta电位的影响和COD去除率的影响很大,表明赤泥PAFC明显优于同类产品,色度、COD去除率高。试验进一步得到PAFC和PFS按比例协同混凝,可进一步降低COD,解决印染污水的升级处理问题。     

涂铁污泥吸附处理中低浓度氨氮废水

未经处理或处理不完全的含氮污染物的任意排放给环境造成极大的危害,而采用传统方法处理中低浓度氨氮废水效率不高.文中以某污水处理厂的剩余活性污泥为基质,其表面经一定浓度的氯化铁溶液改性2 h后用作吸附剂处理中低浓度氨氮废水.实验结果表明:室温时经0.15 mol/L的氯化铁溶液改性的涂铁污泥用量5 g/L,pH值为9,反应40 min即可达到氨氮去除率95%以上,且该吸附反应符合拟二级速率方程.将此工艺条件用于处理氨氮浓度为102.68 mg/L、COD为362 mg/L的实际工业废水,处理后滤液中氨氮浓度9.2 mg/L、COD 83 mg/L,达到《污水综合排放标准(GB8978-1996)》一级标准(NH4+浓度<15 mg/L和COD<100 mg/L).     

生物法处理冷轧高浓度含铬废水的中试研究

概述了微生物法应用于冷轧高浓度含铬废水处理的中试装置和工艺流程.选用彩涂和硅钢高浓度含铬废水作为废水来源,试验了微生物对不同含铬废水中Cr6 、T-Cr以及COD的去除效果.中试结果表明,生物法除铬工艺可适用于上述两种含铬废水的处理,二者出水中Cr6 的平均浓度分别为0.02 mg/L和0.04 mg/L,T-Cr平均浓度分别为0.71 mg/L和0.74 mg/L,满足废水排放标准(Cr6 ＜0.5 mg/L,T-Cr＜1.5 mg/L).同时,对于含较高浓度COD(＞3 g/L)的含铬废水,该工艺可去除60%以上的COD;对于含较低浓度COD(＜3 g/L)的含铬废水,COD去除率低于25%,投加絮凝剂是提高该废水COD去除率的有效途径之一.     

Anaerobic Degradation of Sulfate Laden Organics Employing Different Reactor System Configurations

Anaerobic degradation of sulfate laden organics has been investigated employing bench-scale models of an upflow anaerobic sludge blanket (UASB) reactor, anaerobic baffled reactor (ABR), and hybrid ABR (HABR). Results indicated chemical oxygen demand (COD) removal over 65% in all three systems at a COD/SO42? ratio of 8.57–8.59. However, the performance deteriorated at a low COD/SO42? ratio of 6.92–7.05 with a reduction in COD removal to 41–55%. Supplementation of limiting nutrients improved COD removal ( ≈ 94.5%) in an UASB system and indicated nutrient deficiency as a primary cause of poor performance. However, poor COD removal (45.92–56.12%) in ABR and HABR indicated a severe inhibition of microbial consortia by sulfide. This study revealed that system configuration aggravated the problem of sulfide toxicity due to sequential phase separation in ABR and HABR systems at low dissolved sulfide concentration relative to the UASB reactor, a single-phase system. Sulfate removal was over 88% in all three systems.     

Soluble Microbial Products in ABR Treating Low-Strength Wastewater

The chemical composition, molecular weight (MW) distribution, and biodegradability (both aerobic and anaerobic) of soluble microbial products (SMPs) in an anaerobic baffled reactor (ABR) treating low-strength wastewater were investigated. The effect of various process parameters on the production of SMPs was also examined. Results indicated that high MW (>300 kDa) compounds were produced in the middle compartments of the reactor and formed 22% of the effluent chemical oxygen demand (COD). This fraction was found to be 86% degradable under aerobic conditions but only 4% under anaerobic conditions. Low MW (<1 kDa) material represented the highest portion (36%) of the effluent COD and was mainly found in the first compartment of the ABR and in the effluent. This fraction was more easily degraded under anaerobic conditions (33%) than aerobic conditions (17%). Analysis of a hydrolyzed sample of the high MW fraction revealed the presence of several sugars and volatile fatty acids. Therefore, it was concluded that the high MW material contains heteropolysaccharides. Nuclear magnetic resonance analysis of the low MW fraction revealed the possible presence of alcohol, carboxylate, and aromatic chemical groups. SMP production increased with increasing hydraulic retention time (HRT), probably due to enhanced biomass decay at high HRTs, and also increased with decreasing temperature, probably due to increased stress on the biomass and a reduced metabolism of the SMP at low temperatures. Finally, SMP production in an ABR containing higher levels of initial biomass concentration was greater than for an ABR operating at the same conditions but with lower levels of initial biomass.     

高铁酸盐对焦化废水中COD、NH_3-N的处理效果的研究

高铁酸盐加入量对COD和NH3-N去除效果的实验结果表明:在常温下,当高铁酸盐的加入量为14mg/L时,焦化废水中COD的质量浓度由320mg/L下降到88mg/L,去除率达72.5%;NH3-N质量浓度由68mg/L下降到14.9mg/L,去除率达78.1%。     

Contribution of the ozonation pre-treatment to the biodegradation of aqueous solutions of 2,4-dichlorophenol

The effect of ozonation on the biodegradability of 100-ppm aqueous solutions of 2,4-dichlorophenol has been investigated. BOD at 5, 10 and 21 days, BOD/COD and BOD/TOC ratios and the average oxidation state are presented. Biodegradability measured as BOD5/COD ratio was increased from 0 of the original solution to 0.25 at the moment of removing all the initial compound (corresponding to an ozone dose of 0.12 g L-1, 0.48 for BOD21/COD ratio). To test the effect of this pre-treatment, the biological oxidation of these pre-ozonated solutions was performed in two semi-continuous stirred tank reactors, one with non-acclimated sludge and one with acclimated-to-phenol sludge. The study showed that the TOC content of the pre-treated solution could be removed up to 68% by an aerobic biological treatment as well as co-digested with municipal wastewater (TOC removal up to 82%), with similar operating retention times to a municipal wastewater plant (12-24 h). Kinetic studies based on Monod model have also been carried out. Pseudo-first-order kinetic constants were found to be in the range of 0.5-0.8 L g TVSS-1 h-1.     

Activated Carbon Addition to an Activated Sludge Model Reactor for Color Removal from a Cotton Textile Processing Wastewater

Color removal from cotton textile processing wastewater by addition of powdered activated carbon (PAC) into a lab-scale activated sludge system was examined. The activated sludge system was continuously operated in different sludge ages (SRTs) and hydraulic retention times (HRTs). SRT = 30?d and HRT = 1.6?d operation resulted in up to 36% color removal and 94% COD removal. PAC was added 100, 200, and 400 mg/L into the activated sludge system under these operating conditions. The results indicated that 100 mg/L PAC was sufficient to remove the maximum color measured (up to 50 m?1) from the wastewater. The addition of PAC did not affect chemical oxygen demand (COD) removal significantly. Oxygen uptake rate (OUR) tests were also performed to investigate the microbial activities controlling the system performance. The average OUR was 74.1 mg/L/h without PAC addition while it was 70 mg/L/h with PAC addition. Adsorbable organic halogens of the effluent wastewater decreased from 400 to 50 μg/L with the addition of PAC. Toxicity dilution factor decreased from 2 to 1.5 with the PAC addition into the activated sludge system.     

2,4,6 Tri-Chlorophenol Containing Wastewater Treatment Using a Hybrid-Loop Bioreactor System

A hybrid-loop bioreactor system consisting of a packed column biofilm and an aerated tank bioreactor with an effluent recycle was used for biological treatment of 2,4,6 tri-chlorophenol (TCP) containing synthetic wastewater. The effects of sludge age (solids retention time) on chemical oxygen demand (COD), TCP, and toxicity removal performance of the system were investigated for sludge ages between 5 and 30?days, while the feed COD (2600±100?mg?L?1), TCP (370±10?mg?L?1), and the hydraulic residence time (25?h) were constant. Percent TCP, COD, and toxicity removals increased with increasing sludge age resulting in nearly complete COD, TCP, and toxicity removal at sludge ages above 20?days. Biomass concentrations in the packed column and in the aeration tank increased with increasing sludge age resulting in low reactor TCP concentrations, and therefore, high TCP, COD, and toxicity removals. More than 95% of COD, TCP, and toxicity removal took place in the packed column reactor. Volumetric rates of TCP and COD removal increased due to increasing biomass and decreasing effluent TCP and COD concentrations with increasing sludge age. The specific rate of TCP removal was maximum (120?mg?TCP?gX?1?day?1) at a sludge age of 20?days. TCP inhibition was eliminated by operation of the system at sludge age above 20?days to obtain nearly complete COD, TCP, and toxicity removal.     

UASB Treatment of Tapioca Starch Wastewater

Feasibility of the upflow anaerobic sludge blanket (UASB) process was investigated for the treatment of tapioca starch industry wastewater. After removal of suspended solids by simple gravity settling, starch wastewater was used as a feed. Start-up of a 21.5-L reactor with diluted feed of approximately 3,000 mg∕L chemical oxygen demand (COD) was accomplished in about 6 weeks using seed sludge from an anaerobic pond treating tapioca starch wastewater. By the end of the start-up period, gas productivity of 4–5 m3/m3r?day was obtained. Undiluted supernatant wastewater with a COD concentration of 12,000–24,000 mg∕L was fed during steady-state reactor operation at an organic loading rate of 10–16 kg COD/m3r?day. The upflow velocity was maintained at 0.5 m∕h with a recirculation ratio of 4:1. COD conversion efficiencies >95% and gas productivity of 5–8 m3/m3r?day were obtained. These results indicated that removal of starch solids from wastewater by simple gravity settling was sufficient to obtain satisfactory performance of the UASB process.     

活性炭吸附法去除冶炼废水COD的研究

采用活性炭吸附法对株冶冶炼废水进行了COD去除研究,考察了pH值、反应时间、活性炭用量、反应温度对去除率的影响。结果表明：采用粉末活性炭为吸附剂,当pH值为8．5,搅拌时间为0．5h,活性炭用量为0．25g／L,温度为25℃时,COD去除率达到64．87％,出水COD约为20mg／L。