Impact of salinity on treatment of saline wastewater by sequencing batch biofilm reactor process

High salinity industrial wastewater is difficult to treat using biological treatment system because of the high concentrations of salt.The potential of a sequencing batch biofilm reactor(SBBR)process in treating synthetic high salinity wastewater was evaluated at laboratory scale during a 110-day operation.The reactor was operated in a 12 h cycle,and each cycle consisted of 0.25 h influent addition,8 h aeration,3 h anoxic reaction,0.5 h sedimentation and 0.25 h effluent withdrawal.Gradual increase in salinity gradient was applied during the acclimatization period.The acclimated SBBR system was demonstrated to be an effective process to remove organic compounds and ammonia nitrogen under high salinity conditions with chemical oxygen demand(COD)and ammonia nitrogen(NH3-N)removal efficiencies of 88% and 80%,respectively.The microscopic examination indicated that rather than rotifers or vorticella,the zoogloea,filamentous fungus mingled with a small quantity of swimming infusorians were dominant bacteria in SBBR system.The removal efficiencies close to 80% in COD and 75% in NH3-N were achieved at an organic loading rate(OLR)of 0.96 kg COD/(m3·d),pH of 7.0,salinity of 14 g/L and NH3-N of 30 mg/L.

Treatment of Wastewater with Modified Sequencing Batch Biofilm Reactor Technology

This paper describes the removal of COD and nitrogen from wastewater with modified sequencing batch biofilm reactor. The strategy of simultaneous feeding and draining was explored.The results show that introduction of a new batch of wastewater and withdrawal of the purified water can be conducted simultaneously with the maximum volumetric exchange rate of about 70%.Application of this feeding and draining mode leads to the reduction of the cycle time, the increase of the utilization of the reactor volume and the simplification of the reactor structure. The treatment of a synthetic wastewater containing COD and nitrogen was investigated. The operation mode of F(D) O ( i.e ., simultaneous feeding and draining followed by the aerobic condition) was adopted. It was found that COD was degraded very fast in the initial reaction period of time, then reduced slowly and the ammonia nitrogen and nitrate nitrogen concentrations decreased and increased with time respectively, while the nitrite nitrogen level increased first and then reduced. The relationship between the COD or ammonia nitrogen loading and its removal rate was examined, and the removal of COD, ammonia nitrogen and total nitrogen could exceed 95%, 90% and 80% respectively. The fact that nitrogen could be removed more completely under constant aeration (aerobic condition) of the SBBR operation mode is very interesting and could be explained in several respects.

Research Development and Application of Nitrogen and Phosphorus Removal in Sequencing Batch Biofilm Reactor

Frequent variations of the wastewater quality and quantity and other uncertain factors are the challenges faced by many wastewater treatment plants during the operation. Sequencing batch biofilm reactor（ SBBR） process provides a new idea for an effective solution to this problem. This paper introduces the basic processes and characteristics of the sequencing batch biofilm reactor（ SBBR） process,and summarizes the research status of this process in wastewater treatment. Factors affecting the nitrogen and phosphorus removal effect of the SBBR process are also analyzed.

Performance of Sequencing Biofilm Batch Reactor(SBBR) under Micro-aerobic Condition for Aniline-Contaminated Wastewater Treatment

The performance of sequencing biofilm batch reactor( SBBR) under micro-aerobic condition for aniline-contaminated wastewater treatment was investigated in this study. Dissolved oxygen( DO) and aniline concentrations were selected as the operating variables to analyze,model,and optimize the process. In order to analyze the process,5 dependent parameters,chemical oxygen demand( COD),aniline,ammonium,total nitrogen( TN),and total phosphorous( TP) removal as the process responses were studied. From the results, increase in DO concentration could promote the removal of COD,aniline,ammonium,and TN,while increase in aniline concentration has a slightly negative impact on the removal of pollutants. The optimum DO concentration was found to be 0. 4-0. 5 mg /L. The removal efficiencies for COD,aniline,ammonium,and TN at the optimum point( DO concentration0. 5 mg /L,aniline concentration 11 mg /L) were 95. 84%,100%,75. 72%,and 45. 39%,respectively. The oxidative deamination was the main degradation method for aniline under micro-aerobic condition. Simultaneously nitrification-denitrification( SND)process performed under micro-aerobic condition and about 20%-40% nitrogen was removed by SND.

Effect of seeding biofloc on the nitrification establishment in moving bed biofilm reactor(MBBR)

In recirculating aquaculture systems,nitrification is usually accelerated by inoculating nitrifier or mature biocarriers.In this study,the performance of the establishment of nitrification in the MBBR according to three different strategies:conventional method(Control group A),inoculation with biofloc recovered from a tilapia biofloc culture system(Group B),and addition with extra nitrite(Group C)in the Moving bed biofilm reactor(MBBR)was compared.Among them,the biofloc-inoculated group considerably accelerated the nitrification process in the MBBR(38 d),which is roughly 18 d faster than the control group(A)(56 d)and 21 d faster than group C(59 d).Less ammonia(8 mg/L NH_(4)^(+)-N,10 mg/L in other groups)and external nitrite(2 mg/L NO_(2)􀀀^(-)N)in the influent caused effluent ammonia to drop more slowly(5 d slower than the control group,8 d slower than the B group),which is detrimental to the nitrification process’development.Notably,the influent’s hydraulic retention time(HRT)was reduced from 12 h to 6 h following the successful establishment of nitrification.During the adaptation to reduced HRT,the MBBR inoculated with biofloc experienced short-term changes in the water quality index of the effluent water,whereas the other groups did not.The biofilm seeded with biofloc had the highest mean gray value ratio(1.42)of live/dead cell fluorescence,which grew better and could cover the entire groove under multiple microscope observations.However,the other groups did not demonstrate a similar trend.In summary,the research found that seeding biofloc use as nitrification bioaugmentation into the MBBR of the recirculating aquaculture system(RAS)to greatly speed up the nitrification process.

侧流与主流磷回收工艺对比及调控因子分析

从污水中回收磷是缓解磷资源危机的有效途径,目前,污水处理厂常用的磷回收工艺主要为从剩余污泥中回收磷的侧流工艺,存在工艺复杂、回收效率低等问题.以生物膜为主体的主流磷回收工艺可实现磷的同步去除与富集,工艺简单且高效,因此更具发展前景.两种工艺在运行原理及模式上存在显著差异,因此对两者的调控措施不尽相同.本文分别以A^(2)O工艺和生物膜序批式反应器工艺为代表,对比了侧流和主流磷回收工艺在运行原理及模式上的异同,并以聚磷菌的代谢机理为基础,总结了温度、pH值、水力停留时间、溶解氧、碳源和蓄磷量等调控因子对两种工艺产生的影响,并阐述了其差异化机制,以期为生物膜磷回收工艺的进一步发展提供参考.

厌氧-好氧-缺氧SBBR工艺对垃圾渗滤液深度脱氮处理的试验

传统的垃圾渗滤液生化处理工艺以厌氧-好氧(AO)为主,存在总氮(TN)去除率较低的问题。为提高垃圾渗滤液的TN去除率和去除速率,本研究采用序批式生物膜反应器(SBBR)工艺处理COD_(Cr)质量浓度为7760 mg/L、TN质量浓度为1200 mg/L的实际垃圾渗滤液。该SBBR的运行模式为厌氧-好氧-缺氧运行,在不增加外加碳源的情况下,经过85 d的启动和驯化,出水TN质量浓度低于20 mg/L,TN的去除效率>97%。与序批式反应器(SBR)相比,投加填料提高了同步硝化反硝化(SND)的去除效率,周期从19.5 h缩短到13.75 h。高通量分析表明,SBBR的优势类群为变形菌门(26.43%),而SBR的优势类群为绿弯菌门(28.53%),不同的优势菌群可能是SBBR相比SBR脱氮效率更高的原因之一。

碱激活PMS氧化法协同SBBR深度处理焦化废水研究

采用碱激活过一硫酸盐(PMS)氧化法协同序批式生物膜反应器(SBBR)工艺深度处理焦化废水,研究当以NaOH作为激活剂时,pH、PMS浓度和温度对碱/PMS体系去除焦化废水生化出水COD和色度的影响,之后考察SBBR工艺处理碱/PMS体系出水的效果。研究结果表明,碱/PMS体系深度处理焦化废水的最佳条件为温度25℃、pH=10、PMS投加浓度7 mmol/L、反应时间4 h,在此条件下色度和COD的去除率分别为96.1%和45.9%。电子顺磁共振实验表明碱/PMS体系存在^(1)O_(2)、O_(2)•-、∙OH和SO_(4)•-等活性氧物种。废水经碱/PMS体系处理后可生化性提高,之后经SBBR工艺进一步处理后出水COD<60 mg/L。总体而言,碱激活PMS氧化法协同SBBR工艺对COD的平均去除率达66.7%。焦化废水生化出水处理前后的三维荧光光谱分析表明,碱/PMS体系协同SBBR工艺能去除焦化废水生化出水中的芳香蛋白类物质和类腐殖酸物质。

持续负荷冲击下AnSBBR运行性能及群落结构响应

以厌氧序批式生物膜反应器(AnSBBR)处理葡萄酒生产废水,考察反应器在持续负荷冲击下的运行特性及群落结构响应.结果显示,持续负荷冲击的前13d(29~41d),反应器运行稳定;因逐渐增加的氢分压和挥发性脂肪酸(VFAs),到56d时系统稳定性降低(VFA/TA=0.72),乙酸比产甲烷活性(SMA)降低46.2%,但氢利用速率(HUR)增加69.2%,辅酶F420浓度增加11.9%.在42d时仅外层的Slime-EPS浓度明显增加(34.1%);在56d时TB-EPS和LB-EPS浓度增加61.3%和62.8%,其PN/PS比值增加197.8%和126.0%,负荷冲击诱导EPS分泌大量的应急性蛋白类产物,其电活性物质提高了系统的电子传递活性(35.5%).Illumina MiSeq显示,负荷冲击下Desulfovibrio、Ruminococcus和Geobacter等产酸菌丰度降低,而Methanobacterium丰度由32.2%增至50.9%.生物膜系统通过逐级EPS分泌和强化还原CO_(2)产甲烷来响应持续负荷冲击的影响.

移动床生物膜反应器内典型水质因素对氧转移能力的影响

在污水处理节能降耗与“双碳”战略背景下,为进一步实现污水处理环节的提质增效与节能降碳,从提高氧转移能力的角度出发,在移动床生物膜反应器内,开展了水质因素对氧转移能力的影响研究,并从气泡Sauter平均直径、气泡平均上升速度和气含率等方面,定量分析了氧转移能力影响机制。结果表明:当十二烷基硫酸钠(SDS)浓度由0增大至10 mg/L时,不同载体填充率条件下的氧转移能力均降低;但当SDS浓度由12增大为20 mg/L时,氧转移能力逐渐提高;生物膜载体的存在削弱了SDS对氧转移能力的影响。当总溶解性固体(TDS)值由2000增大至12000 mg/L时,提高了氧转移能力;当TDS值大于12000 mg/L后,氧转移能力趋于不变。随着pH值增大,提高了氧转移能力。在实际污水处理过程中,根据不同水质条件下的氧转移能力变化,通过调节曝气强度等方式,可降低污水处理环节的能耗与成本。

MBBR耦合多段AO工艺在大型市政污水处理厂的运行初探和实践成效

新建城市污水处理厂或提标改造老旧污水处理厂普遍存在出水水质差、污染物负荷与占地面积等不可调和的矛盾,基于纵向扩大池容会增加建设成本、高负荷运行具有超标风险,因此,急需一种污泥/容积负荷高、运行稳定、操作简单的污水处理新技术。对此,某大型市政污水处理厂利用移动床生物膜反应器(MBBR)泥膜共混技术提高生化池有效污泥浓度、实现功能微生物的强化和富集,耦合多段AO工艺,经历雨/旱、夏/冬季,已稳定运行227 d,当进水COD_(Cr)、氨氮、TN质量浓度分别为277.97、34.92、45.95 mg/L,对应出水质量浓度分别降低至12.68、0.33、7.55 mg/L,MBBR挂膜前后的氨氮污泥负荷为0.011、0.015 g氨氮/(g MLSS·d)、TN污泥负荷为0.014、0.020 g TN/(g MLSS·d)。系统稳定运行期间,好氧Ⅰ段氨氮硝化速率为7.27 mg/(L·h)、缺氧Ⅰ段NO-3-N还原速率为3.48 mg/(L·h)。结果表明,通过负载微生物和游离污泥的交互作用,寻求复杂微生物群落功能的强化和调控,可以设计出更加合理、高效的污水处理新工艺。

人工海水条件下移动床生物膜反应器快速挂膜启动试验

海水循环水产养殖系统中,生物膜反应器的挂膜时间通常较长。为实现人工海水条件下移动床生物膜反应器(moving-bed biofilm reactor,MBBR)滤片的快速挂膜,通过搅拌滤片,采用低成本的海水配方、专用营养液以及选择多样化的菌种等方法和措施进行了试验,并建立了以氨氮、亚硝酸盐氮水平、滤片颜色和孔隙生成物为指标的评估体系。试验结果表明,相比于化学营养组的56 d,发酵营养组经过46 d即完成了挂膜。挂膜过程中氨氮质量浓度最高为20.36~25.12 mg/L,亚硝酸盐氮质量浓度最高为45.28~53.20 mg/L。

芬顿催化氧化-MBBR工艺处理双氧水生产废水

双氧水废水具有高COD_(cr)、低B/C、可生化性差的特点,采用芬顿-MBBR组合工艺对其进行处理.试验结果表明:当H_(2)O_(2)投加量为4 mL/L,H_(2)O_(2)/Fe^(2+)物质量的比为2时,芬顿-MBBR组合工艺对双氧水废水有良好的高COD_(cr)去除效果.芬顿预处理后,B/C由0.11提高到0.47,在连续进水条件下高COD_(cr)去除率为77.7%,生化单元出水高COD_(cr)质量浓度小于500 mg/L.

高浓度粪便污水处理技术研究

高浓度粪便污水具有污染物浓度高、处理难度大等特点。采用“两级MBBR+磁混凝”工艺对高浓度粪便污水进行现场试验。经过“两级MBBR+磁混凝”处理后,粪便污水COD、TN、NH3-N和TP去除率分别为89.56%、95.76%、97.31%和95.15%,出水水质满足《污水排入城镇下水道水质标准》(GB/T 31962—2015)要求。试验结果表明,“两级MBBR+磁混凝”工艺可以有效处理高浓度粪便污水。

Inhibition and recovery of nitrification in treating real coal gasification wastewater with moving bed biofilm reactor

Moving bed biofilm reactor （MBBR） was used to treat real coal gasification wastewater. Nitrification of the MBBR was inhibited almost completely during start-up period. Sudden increase of influent total NH 3 concentration was the main factor inducing nitrification inhibition. Increasing DO concentration in the bulk liquid （from 2 to 3 mg/L） had little effect on nitrification recovery. Nitrification of the MBBR recovered partially by the addition of nitrifying sludge into the reactor and almost ceased within 5 days. Nitrification ratio of the MBBR achieved 65% within 12 days by increasing dilute ratio of the influent wastewater with tap water. The ratio of nitrification decreased to 25% when influent COD concentration increased from 650 to 1000 mg/L after nitrification recovery and recovered 70% for another 4 days.

Effect of alkalinity on nitrite accumulation in treatment of coal chemical industry wastewater using moving bed biofilm reactor

Nitrogen removal via nitrite （the nitrite pathway） is more suitable for carbon-limited industrial wastewater. Partial nitrification to nitrite is the primary step to achieve nitrogen removal via nitrite. The effect of alkalinity on nitrite accumulation in a continuous process was investigated by progressively increasing the alkalinity dosage ratio （amount of alkalinity to ammonia ratio, mol/mol）. There is a close relationship among alkalinity, pH and the state of matter present in aqueous solution. When alkalinity was insufficient （compared to the theoretical alkalinity amount）, ammonia removal efficiency increased first and then decreased at each alkalinity dosage ratio, with an abrupt removal efficiency peak. Generally, ammonia removal efficiency rose with increasing alkalinity dosage ratio. Ammonia removal efficiency reached to 88% from 23% when alkalinity addition was sufficient. Nitrite accumulation could be achieved by inhibiting nitrite oxidizing bacteria （NOB） by free ammonia （FA） in the early period and free nitrous acid in the later period of nitrification when alkalinity was not adequate. Only FA worked to inhibit the activity of NOB when alkalinity addition was sufficient.

Effect of the C:N:P ratio on the denitrifying dephosphatation in a sequencing batch biofilm reactor(SBBR)

A series of investigations were conducted using sequencing batch biofilm reactor（SBBR） to explore the influence of C：N：P ratio on biological dephosphatation including the denitrifying dephosphatation and the denitrification process.Biomass in the reactor occurred mainly in the form of a biofilm attached to completely submerged disks.Acetic acid was used as the source of organic carbon.C：N：P ratios have had a significant effect on the profiles of phosphate release and phosphate uptake and nitrogen removal.The highest rates of phosphate release and phosphate uptake were recorded at the C：N：P ratio of 140：70：7.The C：N ratio of 2.5：1 ensured complete denitrification.The highest rate of denitrification was achieved at the C：N：P ratio of 140：35：7.The increase of nitrogen load caused an increase in phosphates removal until a ratio C：N：P of 140：140：7.Bacteria of the biofilm exposed to alternate conditions of mixing and aeration exhibited enhanced intracellular accumulation of polyphosphates.Also,the structure of the biofilm encouraged anaerobic-aerobic as well as anoxic-anaerobic and absolutely anaerobic conditions in a SBBR.These heterogeneous conditions in the presence of nitrates may be a significant factor determining the promotion of denitrifying polyphosphate accumulating organism（DNPAO） development.

The effect of bubble plume on oxygen transfer for moving bed biofilm reactor

The movement of the bubble plume plays an important role in the operation of a moving bed biofilm reactor （MBBR）, and it directly affects the contact and the mixture of the gas-liquid-solid phases in the aeration tank and also the oxygen transfer from the gas phase to the liquid phase. In this study, the velocity field is determined by a 4-frame PTV as well as the time-averaged and timedependent velocity distributions. The velocity distribution of the bubble plume is analyzed to evaluate the operating efficiency of the MBBR. The results show that the aeration rate is one of the main factors that sway the velocity distribution of the bubble plumes and affect the operating efficiency of the reactor.

Mechanism studies on nitrogen removal when treating ammonium-rich leachate by sequencing batch biofilm reactor

The nitrogen removal mechanism was studied and analyzed when treating the ammonium-rich landfill leachate by a set of sequencing batch biofilm reactors(SBBRs),which was designed independently.At the liquid temperature of(32P0.4)°C,and after a 58-days domestica-tion period and a 33-days stabilization period,the efficiency of ammonium removal in the SBBR went up to 95%.Highly frequent intermittent aeration suppressed the activity of nitratebacteria,and also eliminated the influence on the activity of anaerobic ammonium oxidation(ANAMMOX)bacteria and nitritebacteria.This influence was caused by the accumulation of nitrous acid and the undulation of pH.During the aeration stage,the concentration of dissolved oxygen was controlled at 1.2-1.4 mg/L.The nitritebacteria became dominant and nitrite accumulated gradually.During the anoxic stage,along with the concentration debasement of the dissolved oxygen,ANAMMOX bacteria became domi-nant;then,the nitrite that was accumulated in the aeration stage was wiped off with ammonium simultaneously.

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.