Anaerobic-aerobic processes for the treatment of textile dyeing wastewater containing three commercial reactive azo dyes:Effect of number of stages and bioreactor type

In this study,the effect of number of stages and bioreactor type on the removal performance of a sequential anaerobic-aerobic process employing activated sludge for the treatment of a simulated textile dyeing wastewater containing three commercial reactive azo dyes was considered.Two stage processes performed better than one stage ones,both in terms of overall organic and color removal,as well as the higher contribution of anaerobic stage to the overall removal performance,thereby making them a more energy efficient option.The employment of a moving bed sequencing batch biofilm reactor,which uses both suspended and attached biomass,for the implementation of the anaerobic stage of the process,was compared with a sequencing batch reactor that only employs suspended biomass.The results showed that,although there was no meaningful difference in biomass concentration between the two bioreactors,the latter reactor had better performance in terms of chemical oxygen demand(COD)removal efficiency and rate and color removal rate.Further exploratory tests revealed a difference between the roles of suspended and attached bacterial populations,with the former yielding better color removal whilst the latter had better COD removal performance.The sequential anaerobic–aerobic process,employing an aerobic membrane bioreactor in the aerobic stage resulted in COD and color removal of 77.1±7.9%and 79.9±1.5%,respectively.The incomplete COD and color removal was attributed to the presence of soluble microbial products in the effluent and the autoxidation of dye reduction metabolites,respectively.Also,aerobic partial mineralization of the dye reduction metabolites,was experimentally observed.

ATP content and biomass activity in sequential anaerobic／aerobic reactors

Specific ATP content of volatile solids was measured to characterize the sludge activity in a sequential anaerobic/aerobic wastewater treatment system, with an upflow anaerobic sludge blanket (UASB) reactor and a three-phase aerobic fluidized bed (AFB) reactor. The wastewater COD level was 2000-3000 mg/L in simulation of real textile wastewater. The ATP content and the specific ATP contents of volatile solids at different heights of the UASB reactor and those of the suspended and immobilized biomass in the AFB reactor were measured. In the UASB reactor, the maximum value of specific ATP (0.85 mg ATP/g VS) was obtained at a hydraulic retention time (HRT) 7.14 h in the blanket solution. In the AFB reactor, the specific ATP content of suspended biomass was higher than that of immobilized biomass and increased with hydraulic retention time reaching a maximum value of 1.6 mg ATP/g VS at hydraulic retention time 4.35 h. The ATP content of anaerobes in the UASB effluent declined rapidly under aerobic conditions following a 2nd-order kinetic model.

Function of anaerobic portion in a conventional sequencing batch reactor

The performance of SBRs treating two kinds of wastewater(synthetic wastewater con- taining polyvinyl alcohol and effluent from a coke-plant wastewater treatment system)was investi- gated in this study,in order to examine the exact function of anaerobic portion in a conventional SBR.The set up of 4-or 8-hour anaerobic mixing period in a SBR's cycle did not benefit for PVA degradation.While an anaerobic reactor seeded with anaerobic sludge could partly hydrolyse and acidify PVA into readily-degradable intermediates.During the anaerobic fill period of an SBR treat- ing the effluent from a coke-plant wastewater treatment system,the organic concentration was re- duced to certain extent due to the adsorption of activated sludge and dilution of the mixed liquor from the previous cycle.Parts of readily-degradable organics in the influent were utilised by denitri- fiers as carbon source.The biomass in a conventional SBR was alternatively imposed to aerobic and anaerobic conditions in its operating cycle,the environmental conditions needed for anaerobic hy- drolization and acidification of refractory organics could not occur in such an SBR.

Biological Nitrogen and COD Removal of Nutrient-Rich Wastewater Using Aerobic and Anaerobic Reactors

A preliminary study on nitrogen and organic removal efficiency of a lab-scale system using aerobic and an-aerobic reactors was performed. A simulated wastewater containing elevated levels of nitrogen was used. This paper aims to compare the efficiency of aerobic and anaerobic reactors in achieving nitrogen and chemical oxygen demand (COD) removal of nutrient-rich wastewater. It also presents the start-up experi-mentation conducted on simulated wastewater using two different reactors configured as aerobic and anaero-bic. Start-up experiments were carried out using a 5-liter acrylic aerobic reactor and a 4-liter flask anaerobic reactor containing activated sludge taken from De La Salle University (DLSU) wastewater treatment plant as a source of inoculum. Simulated wastewater was continuously fed to the two reactors and the time course of biomass growth was monitored by measuring the biomass concentration represented by mixed liquor volatile solids (MLVS). The time course of organic pollutant reduction by measuring the chemical oxygen demand (COD) was conducted until steady state condition was reached. On the other hand, COD and nitrogen tests such as Ammonia nitrogen (NH3-N), Nitrite nitrogen (NO2--N), Nitrate nitrogen (NO3--N) were also per-formed using 5 batch aerobic reactors containing different concentrations of wastewater and a single batch anaerobic reactor to see the effect of different feed concentrations in the removal of nitrogen. Preliminary results showed that 98% reduction in COD was obtained in aerobic reactor, as supported by increasing con-centration of MLVS, with a hydraulic retention time (HRT) of 5 hours after 11 days while 34% reduction in COD was obtained in anaerobic reactor with the same HRT after 14 days.

中国白酒企业酿酒废水处理现状与展望

酿酒废水产生量大、成分复杂且处理难度高,是极具中国特色的高浓度有机废水。本文详细介绍了中国白酒企业的酿酒废水处理现状,从工艺流程、技术特点以及适用范围等方面进行深度剖析总结,发现我国形成了以厌氧微生物处理工艺为主,预处理、好氧微生物工艺为辅的成熟工艺,不仅实现了酿酒废水的达标处理,而且所产甲烷成为企业热能和电力的重要补充。另外,在国家水资源循环利用政策的推动下,针对酿酒废水水质特点开展的资源化利用研究也在如火如荼的进行中,其中包括回锅重蒸、高附加值成分的提取以及微生物碳源制备等新技术,为酿酒废水处理提供了新的可能,助推白酒企业绿色低碳发展。

厌-好氧交替工艺处理辽河油田废水的试验

采用厌－好氧交替（ＡＡＡ）工艺处理适当稀释或原浓度的油田废水，进水ＣＯＤ３６０—９５０ｍｇ／Ｌ，ＣＯＤ去除率均保持在６０％左右．经过厌氧ＵＡＳＢ反应器处理后的废水，再经ＡＡＡ工艺进行处理，在ＨＲＴ８—１２ｈ的条件下，其ＣＯＤ浓度能够从３５０ｍｇ／Ｌ降到１６０—２４０ｍｇ／Ｌ，ＣＯＤ去除率３１％—４８．５％．对于ＣＯＤ浓度为１６０—１８０ｍｇ／Ｌ的废水，采用好氧接触氧化法作为好氧二级处理，其出水ＣＯＤ去除率在５０％—６０％，出水ＣＯＤ浓度一般接近８０ｍｇ／Ｌ左右．

有机碳源条件下厌氧氨氧化ASBR反应器中的主要反应

采用5个已稳定运行在厌氧氨氧化状态的ASBR反应器，通过COD、氨氮、亚硝酸盐氮、硝酸盐氮、pH等指标的监测和好氧硝化菌、异养反硝化菌的测定，研究了不同有机碳源条件下反应器中发生的主要反应．结果表明，反应器中存在好氧硝化菌、异养反硝化菌和厌氧氨氧化菌．在COD、氨氮、亚硝酸盐氮等存在条件下，可发生好氧硝化、厌氧氨氧化和异养反硝化反应，先是好氧硝化反应、厌氧氨氧化反应和异养反硝化反应共存，其后依次是异养反硝化反应和厌氧氨氧化反应占主导地位．当C／NO2^--N在1．7～1．9范围内时，C／NH4^＋-N为1．7的1号反应器具有最佳的厌氧氨氧化效果，反应结束时其COD去除率、NH4^＋-N去除率、NO2^--N去除率分别为100％、81．7％和74．4％．

微氧水处理技术的特性及应用研究进展

对于传统的好氧和厌氧而言,微氧水处理技术是在克服好氧反应能耗较大,厌氧反应器对于设备要求较高而出现的。微氧过程中包含的反应有短程硝化和反硝化、同时硝化与反硝化、氧化降解等反应,因此微氧水处理技术可以应用于有机物降解和深度处理。由于显著降低了曝气量,又不需要较高的设备要求,因此又是一种节能的技术。

厌氧-好氧工艺处理制药废水的中试研究

将由厌氧折流板反应器(ABR)、移动床生物膜反应器(MBBR)和膜生物反应器(MBR)组合而成的厌氧-好氧工艺用于处理制药废水的中试研究。试验结果表明,当原水SS平均值为1000 mg/L,COD为10 000 mg/L,NH3-N为500mg/L时,出水浊度、COD和NH3-N分别为3 NTU、500 mg/L以及10 mg/L以下,去除率分别为98%、95%和98%以上。

改性活性污泥高效处理高浓度硫酸盐废水

对城市生活污水厂的好氧活性污泥进行厌氧改性,利用改性后的厌氧污泥对高浓度硫酸盐废水进行处理;考察不同有机碳源、体系初始pH值、接种污泥质量、起始硫酸根质量浓度、初始ρ(COD)/ρ(SO2-4)、亚铁离子及通N2方式等因素对厌氧污泥还原硫酸根能力的影响。间歇式试验结果表明在以乳酸钠为有机碳源,pH值为7,接种污泥质量为20g,初始硫酸根质量浓度为3g/L,ρ(COD)/ρ(SO2-4)为1.45,不加亚铁离子及通入N2的条件下,硫酸根的去除率最高;在间歇式试验最优条件进行半连续试验,硫酸根去除率均大于90%,表明在ρ(COD)/ρ(SO2-4)较低的条件下,能快速启动反应器,高效处理高浓度硫酸盐废水。

集约化猪场废水强化生化处理工艺试验研究

该文采用新型厌氧反应器技术和强化生物脱氮及硝化技术处理猪场废水。试验结果表明:新型厌氧反应器容积CODCr负荷可达8kg/(m3.d)以上,稳定运行CODCr平均去除率为75%;生物脱氮及硝化采用一体式A/O反应器,缺氧段水力停留时间为1h,好氧段水力停留时间为3d,氨氮浓度可控制在10mg/L以下。总出水CODCr平均550mg/L,BOD5平均53.0mg/L,NH3-N平均8.8mg/L,总CODCr去除率87%,总BOD5去除率96%,NH3-N总去除率在98%以上;采用原水碳源优化分配强化生物脱氮,TN去除率为77.11%左右。总出水BOD5/CODCr约0.10,出水CODCr中难生物降解成分占绝大多数,需经过后续物化处理才能达到广东省水污染物控制标准(DB44/26-2001)。

碳氮磷比例失调城市污水的同步脱氮除磷

为解决现行同步脱氮除磷工艺处理南方地区碳、氮、磷比例失调城市污水中,因C/N、C/P偏低,碳源不足而降低脱氮除磷效率的难题,试验以碳源偏低的广州市城市污水为研究对象,采用厌氧/好氧交替运行的SBR系统,通过对厌氧、好氧时段的合理调控,在无需额外添加碳源的条件下,有机物、氨氮、总氮和总磷的平均去除率分别可达90%、72%、41%和99%,不仅能使有机物和氮的出水指标达到国家排放标准,而且总磷出水浓度能达0.5 mg/L以下。通过进一步分析同步高效脱氮除磷的影响因素和控制条件,得出合理污泥龄的控制是实现同步脱氮除磷的关键,厌氧/好氧交替运行的方式不仅强化了磷的释放和吸收,而且降低了碳源偏低和硝酸盐对同步脱氮除磷影响的结论。

厌氧-好氧处理变性淀粉生产废水工程实例

利用膨胀颗粒污泥床(EGSB)和活性污泥好氧处理工艺相结合处理高浓度变性淀粉生产废水,处理水质可达到国家污水综合排放一级标准。工程实践表明该工艺具有投资与占地面积少,运行效果稳定,可回收能源等优点,具有很高推广价值。

改良型SBR系统处理染料废水的研究

通过试验考察了两种改良型序批式间歇反应器-SBR-系统——“厌氧、好氧”交替运行系统-系统1-和“厌氧+好氧”串联二级系统-系统2-的运行过程,分析了影响系统运行效果的因素,比较了两个系统厌氧阶段、好氧阶段及全过程处理效果的差异,并分析了造成差异的原因.结果表明,两个系统均具有适应能力强、稳定性能好、能够有效地降解污染物的特点;污泥浓度、碳源数量、环境温度均影响系统的运行效果;系统1的厌氧阶段比系统2更有效,系统2的好氧阶段比系统1更有效,系统2的全过程处理效率更高;分析认为生物相组成情况的不同是导致两个系统处理效果差异的主要原因.

厌氧-好氧法处理聚氯乙烯离心母液废水

采用厌氧膨胀颗粒污泥床反应器与内循环式好氧生物膜反应器串联工艺对悬浮聚合法聚氯乙烯离心母液废水进行连续处理实验。在温度为35℃、厌氧反应器水力停留时间为8h、好氧反应器水力停留时间为6h条件下,TOC总去除率达95%以上,厌氧段为50%左右。结果表明:厌氧段还可提高其出水的可生化性;温度对厌氧及整个系统的处理效果影响较大;运行过程中须向离心母液废水中添加氮、磷等营养物质。

厌氧-好氧移动床生物膜工艺处理冰淇淋废水的试验研究

研究了厌氧污泥复合床 好氧移动床生物膜反应器串联工艺 ,处理冰淇淋生产废水的工艺性能和影响因素。试验结果表明 ,在进水CODCr 浓度平均为 3 0 0 0mg L ,厌氧反应器容积负荷 7～ 2 0kg m3·d ,好氧反应器容积负荷 1～5kg m3·d ,系统总水力停留时间 13 1～ 2 8h的条件下 ,该串联工艺的CODCr总去除率大于 90 %

AAC反应器好氧菌的筛选及菌株配伍性能的比较

针对AAC反应器能有效处理番茄酱加工废水和剩余污泥减量化的特点,分离了AAC反应器中的好氧微生物,并通过配伍实验研究了优势微生物对番茄酱加工废水的处理性能。共分离得到29株好氧细菌,根据12hTOC降解率初步确定了6株优势菌。通过配伍比较TOC降解率,得到了两株菌的基础组合,其TOC去除率达到85.29%,单位TOC降解率的菌体增长量为1.89。结合菌体沉降性,最终构建出含有7株菌的高效微生物菌群,单位TOC降解率的菌体增长量为0.94,单位降解率的污泥产量减少了50.26%,沉降性能明显改善,OD600值仅为0.347,出水达到了国家二级标准。

厌氧-好氧序列间歇式反应器处理生物制药废水的研究

采用厌氧序列间歇反应器与好氧序列间歇反应器相结合的技术，处理生物制药废水。结果表明，经７．０ｈ厌氧搅拌处理和６．０ｈ好氧曝气处理，进水ＣＯＤ为１１８０～３０６１ｍｇ／Ｌ，出水ＣＯＤ小于３００ｍｇ／Ｌ，ＣＯＤ去除率在７８９％～９２８％之间，出水ＣＯＤ满足国家生物制药行业废水排放标准要求。

载体好氧预挂膜处理对厌氧附着膜膨胀床反应器的影响

研究了生物腹载体经好氧预挂膜处理对厌氧附着膜膨胀床（ＡＡＦＥＢ）反应器的起动、运行效能、厌氧生物颗粒性状的影响。载体经１０天好氧预挂腹处理后的反应器比对照提前１５天完成起动；且具有较好地耐受有机质负荷和水力负荷冲击的效能。处理反应器中厌氧生物颗粒的一些性能指标值，如最大比产酸活性、最大比产甲烷活性、Ｆ（４２０）、生物膜浓度等均优于对照。另外，两种反应器厌氧生物颗粒内微生物相也存在明显的差异。

基于SBR反应器的ANAMMOX工艺的启动运行

采用SBR反应器,接种好氧硝化污泥,在142 d内于较高负荷下成功启动了厌氧氨氧化反应器。反应器总氮容积负荷(以N计)为0.43 kg/m3.d,总氮去除率最高达到93.3%,平均为80.5%;氨氮和亚硝酸盐氮的去除率最高达到93.9%和99.8%,平均去除率为81.2%和85.7%。在稳定运行阶段,氨氮去除量、亚硝酸盐氮去除量、硝酸盐氮生成量三者之间的比值为1∶1.38∶0.18。反应器启动过程中,出水、进水pH差值的变化趋势由负到正,然后稳定在一定范围内;且污泥性状有较大变化,污泥中微生物所占比率有所提高,整个反应器中适应厌氧氨氧化运行方式的菌种增殖较快。