Feasibility Study on the Treatment of Wastewater Containing High-concentration Hg by Coagulation Sedimentation-Adsorption

For the wastewater containing high-concentration Hg,the feasibility of high-concentration Hg in wastewater treated by coagulation sedimentation,adsorption and the combined process was studied. Research results showed that if using the single coagulation sedimentation process,when FeSO_4·7H_2O dosage was 1. 39 g / L,and NaOH dosage was 0. 40 g / L,it could meet discharge requirement,but the reagent cost was 13. 1yuan / t,which was high. Because that there was subsequent adsorption process,it was selected 0. 28 g / L of FeSO_4·7H_2O and 0. 36 g / L of NaOH,and the estimated reagent cost was 2. 62 yuan / t. In selection process of adsorption materials,powdered activated carbon,granular activated carbon and diatomite all could effectively adsorb Hg,and the technology was feasible. When using the combined process of coagulation sedimentation + adsorption to treat the wastewater containing high-concentration Hg( 800 μg / L),removal rate could reach 99%,and operation cost was 2. 71 yuan. It could meet the requirement of sewage discharged into sewer( 20 μg / L) at the technology,and was acceptable at the economy.Therefore,treatment of wastewater containing high-concentration Hg by the combined process was feasible at the aspects of technology and economy.

Treatment of Wastewater from Dairy Farm by Coagulation Sedimentation

In order to evaluate the processing efficiency of coagulation sedimentation on wastewater from dairy farm and to provide reference for wastewater treat- ment, an experimental study was carried out to investigate effects of coagulant dosage, types, pH, dosage of coagulant aids PAM on removal rate of COD, turbidity and SS in wastewater from dairy farm. The results showed that PAC displayed higher effectiveness in treatment; the removal rates of COD, turbidity and SS were 61.4%, 86.6% and 94.5% respectively when pH was 11.0, PAC dosage was 150 mg/L, and PAM dosage was 4 mg/L. The results indicated that coagulation sedimentation could reduce organic content of wastewater effectively and alleviate the load of subsequent biochemical treatment.

Effects of Coagulation and Ozonation Pretreatments on Biochemical Treatment of Fluid Catalytic Cracking Wastewater

Fluid catalytic cracking (FCC) salty wastewaters, containing quaternary ammonium compounds (QACs), are very difficult to treat by biochemical process. Anoxic/oxic (A/O) biochemical system, based on nitrification and denitrification reactions, was used to assess their possible biodegradation. Because of the negative effects of high salt concentration (3%), heavy metals and toxic organic matter on microorganisms’ activities, some techniques consisting of dilution, coagulation and flocculation, and ozonation pretreatments, were gradually tested to evaluate chemical oxygen demand (COD), ammonia-nitrogen (ammonia-N) and total nitrogen (TN) removal rates. In this process of FCC wastewater, starting with university-domesticated sludge, the ammonia-N and TN removal rates were worst. However, when using domesticated SBR’s sludge and operating with five-fold daily diluted influent (thus reducing salt concentration), the ammonia-N removal reached about 57% while the TN removal rate was less than 37% meaning an amelioration of the nitrification process. However, by reducing the dilution factors, these results were inflected after some days of operation, with ammonia-N removal decreasing and TN barely removed meaning a poor nitrification. Even by reducing heavy metals concentration with coagulation/flocculation process, the results never changed. Thereafter, by using ozonation pre-treatment to degrade the detected organic matter of di-tert-butylphenol and certain isoparaffins, COD, ammonia-N and TN removal rates reached 92%, 62% and 61%, respectively. These results showed that the activities of the microorganisms were increased, thus indicating a net denitrification and nitrification reactions improvement.

臭氧氧化+A/O+臭氧氧化工艺在化工园区污水处理厂中的运用

化工园区废水成分复杂,难降解物质多。某化工园区污水处理厂选用分质强化混凝沉淀+臭氧氧化作为预处理工艺,同时采用水解酸化+厌氧好氧(Anaerobic/Oxic,A/O)的二级处理工艺和混凝沉淀+臭氧氧化的深度处理工艺。实际运行结果表明,该组合工艺对化学需氧量(Chemical Oxygen Demand,COD)的平均去除率为85.7%,COD去除效果良好,出水水质优于《城镇污水处理厂污染物排放标准》(GB 18918—2002)的一级A标准。

物化预处理-生化组合工艺处理草甘膦生产废水工程实例

对不同工艺废水采用物化方法分质预处理后,利用厌氧-缺氧-CAST组合工艺处理综合废水,设计处理量为470 m^(3)/d。运行实践表明:中和反应-混凝沉淀对总磷的去除率可以达到46%,整个工艺处理出水COD稳定低于500 mg/L,总磷稳定低于8 mg/L,出水水质达到接管要求。

污水中阴离子表面活性剂的影响及去除

文章系统研究了应用较为广泛的阴离子表面活性剂——十二烷基苯磺酸钠(SDBS)对生物池中污染物(氨氮、总磷、硝态氮)的去除影响以及不同混凝剂[聚合氯化铝(PAC)、硫酸铝(AS)、聚合硫酸铁(PFS)、三氯化铁(FeCl_(3))]对SDBS去除效能和最佳投加位点的选择。试验结果表明,氨氮和总磷的去除率随着SDBS浓度的增加会明显降低,SDBS对以上两种污染物的去除有显著的抑制作用,而SDBS对硝态氮的去除基本无影响。通过进一步试验得出,FeCl_(3)作为混凝剂可以更有效去除SDBS,当FeCl_(3)与SDBS在最佳质量配比(3∶1)时,SDBS的去除率可达到78.3%。在提升泵站、初沉池出口、外回流液中投加FeCl_(3)对SDBS皆有明显的去除效果,但在初沉池出水中投加时SDBS的去除效果最佳。

混凝沉淀法处理冶金含氟废水工艺研究

水中氟含量超标会对环境造成巨大影响,目前冶金行业普遍采用混凝沉淀法处理含氟废水。因此,针对混凝沉淀法除氟工艺中影响因素多、除氟效果缺少综合评估的问题,以某钢铁公司生产过程中产生的含氟废水为对象进行研究。首先通过正交实验考察pH、聚氯化铝(PAC)投加量、聚丙烯酰胺(PAM)投加量、PAC搅拌时间、PAM搅拌时间对含氟废水除氟效率影响的主次关系。研究结果表明,影响除氟效率的主次因素排序依次为pH、PAC搅拌时间、PAC投加量、PAM搅拌时间、PAM投加量。此外,对上述因素及温度等单因素变化对除氟效率的影响进行了研究。结果表明,最佳条件:pH为7、PAC投加量为70 mL、PAM投加量为2.5 mL、PAC搅拌时间为15 min、PAM搅拌时间为30 min、温度为30℃,在此最佳条件下除氟效率最高,可以达到99.3%。实际工程应用中,混凝沉淀法对氟离子总去除率在80%~90%,出水氟含量保持在7 mg/L左右,能够满足氟离子达标排放的要求。

“A/RPIR+磁混凝沉淀”组合工艺处理城镇废水的稳定运行效能分析

“A/RPIR+磁混凝沉淀”组合工艺具有运行能耗低,投资节省,占地少,运行稳定,出水水质好等优势,已在河道黑臭水体治理及市政污水处理领域得到广泛应用。本文对某市政污水处理厂(A/RPIR+磁混凝沉淀工艺、设计规模10×10^(4)m^(3)/d)的稳定运行效能进行分析评估。结果表明,水厂出水水质全部稳定达标,年平均吨水电耗为0.196kWh,产出泥饼含水率相对稳定,平均为79.5%,日泥饼产量为74.1 t,污泥产率为1.14×10^(4)TDS/m^(3)。污水厂整体运行效能良好。

聚合氯化铝-聚丙烯酰胺处理含氟废水研究

使用聚合氯化铝(PAC)-聚丙烯酰胺(PAM)联合处理含氟废水,考察了PAC投加量、PAM浓度、pH值、反应时间以及搅拌速度对除氟效果的影响。结果表明,在PAC投加量4400 mg/L、PAM浓度1 mg/L、溶液pH值7.0、反应时间20 min、搅拌速度300 r/min时,氟去除率达97.98%,除氟后溶液中氟离子残余浓度为0.81 mg/L。溶液中杂质离子的存在会降低PAC的除氟性能。

宜昌市某园区难降解工业废水深度处理试验及改造工程设计

工业园区难降解工业废水的经济性达标一直是亟待解决的难题。宜昌市某工业园区污水处理厂主要处理造纸厂及食品加工厂预处理后的难降解工业废水,长期存在出水不达标、运行成本高的难题。研究以现状污水处理厂难降解有机污染物为研究对象,开展了活性炭静态吸附、混凝沉淀和类芬顿催化氧化对比试验研究,比较了3种方法的处理效果。结果表明,在pH值=5.0~5.5时,类芬顿催化氧化工艺对CODCr的总体去除率最高可达73%以上,出水水质可稳定达到《城镇污水处理厂污染物排放标准》(GB 18918—2002)一级A排放标准,新增运行成本为0.905元/m^(3)。基于深度处理对比试验结果,针对该污水处理厂用地紧张的现状,结合现有土地及各构筑物单元布置情况,提出了提标改造方案,可为类似高比例工业污水厂升级改造提供参考借鉴。

医药产业园区废水处理工程实例

针对山东某医药产业园区生产废水高COD、高氨氮、高盐分和可生化性差等特点,设计采用蒸氨-MVR蒸发结晶-臭氧催化氧化-A^(2)/O-深度处理工艺,处理水量为500 m^(3)/d。工程实践表明,该工艺对COD、氨氮、总氮、总磷和SS的去除率分别达到了97.1%、89.9%、85.9%、93.5%和96.3%,相应出水水质分别为358、27、52、0.62和40 mg/L,出水水质满足GB/T 31962—2015《污水排入城镇下水道水质标准》中的A级排放标准。

印刷油墨废水处理工程实例

针对地面材料厂印刷油墨废水有机物含量高、溶解性固体含量高、可生化性差等特点,采用“两级混凝沉淀+碟管式反渗透(DTRO)”工艺进行处理。文章介绍了工艺流程、工艺单元及设备、处理效果及技术经济性。稳定运行结果表明,该工艺对CODCr、BOD5、SS、NH_(3)-N、DS、TS的总去除率分别为99.77%、98.40%、99.90%、99.91%、99.63%、99.65%,出水BOD_(5)、SS、DS平均值分别为20 mg/L、2 mg/L、68 mg/L,优于GB/T 19923—2005《城市污水再生利用工业用水水质》中的洗涤用水水质标准,电费和药剂费用合计为26.14元/m3。

焦化废水生物出水物化协同技术及污染物去除机制研究

焦化废水溶液性质复杂,经生化处理后,仍残留多环芳烃、苯、胺等难降解有机物,不仅对生态环境造成污染,也会对水回用构成技术障碍。随着环保要求的日益提高,亟需强化焦化废水的深度处理工艺,实现焦化废水的“零排放”。本文根据焦化废水生物出水的性质特征,选择混凝沉淀、活性炭吸附和臭氧氧化这三种物化技术来分质去除生物出水中的有机物,考察物化技术协同机制及其工艺有效性,为焦化废水深度处理的工艺路径提供优选方案。

矿井废水处理中混凝沉淀过滤技术应用

矿井废水经过处理后可作为煤矿工业用水,提高水资源利用价值,减轻废水排放引起的环境污染问题。本文以某煤矿项目为例,通过对矿井水来源及水质特点的了解,提出混凝沉淀过滤技术在矿井废水处理中的应用策略,监测污染物排放指标,并从经济效益和生态环境效益进行分析,认为混凝沉淀过滤技术的综合应用效果良好,具有推广价值。

光伏产业含氟废水及工业处理方法进展

近年来我国光伏产业发展迅速,但多晶硅和光伏电池制造过程中会产生大量含氟废水,且污水处理排放含氟标准日益严格,因此光伏废水处理成为光伏企业工艺升级的重点领域。该文总结了现有的含氟废水处理技术,对各类含氟废水处理技术进行了多维度对比,并从企业角度探讨了高效、经济、工业化的含氟废水处理方法;分析了混凝沉淀法和混凝吸附法最新工艺处理流程及效果,提出了含氟废水处理工艺发展方向,对我国光伏企业升级污水治理工艺、实现节能减排和提质增效具有借鉴意义。

EBIS(改良AO)+磁混凝工艺在陕西某城市污水厂提标改造工程中的应用

陕西某城市污水处理厂总设计规模80000 m^(3)/d,其中40000 m^(3)/d生化池利用现状的CASS池进行改造,另外新建40000 m^(3)/d生化池及80000 m^(3)/d规模的深度处理设施。污水处理厂进水主要来源为城市生活污水,混合少量的工业污水,处理工艺采用“预处理+EBSI生化池+磁混凝沉淀池+次氯酸钠消毒”主体工艺,介绍了工程的工艺流程、主要设计参数及运行效果等。出水水质监测指标表明,本项目出水完全满足《陕西省黄河流域污水综合排放标准》(DB61/224-2018)中A标准。

混凝沉淀法处理草甘膦生产废水的试验研究

草甘膦作为一种高效低毒的除草剂,在当前农业生产中被广泛使用。在草甘膦生产过程中,会产生大量含有机磷的废水,含量高达数十mg/L,必须采取合理有效的处理手段,减少甚至消除其对环境的污染。采用混凝沉淀法对草甘膦生产废水中的二甲酯精酯废水和甲醇回收残液进行了处理,研究了混凝剂种类、投加量、反应pH及反应时间对废水COD和TP去除效果的影响。实验表明,投加新型高分子混凝剂聚铝铁比其他几种混凝剂处理效果更好,投资运行成本更低。在混凝剂聚铝铁投加量为0.7g/L、反应pH为5、反应时间为40min时对草甘膦二甲酯精酯废水处理效果最好。此时COD的去除率可在40%以上,TP的去除率可在65%以上。在混凝剂聚铝铁投加量为0.9g/L、反应pH为4、反应时间为40min时对草甘膦甲醇回收残液废水处理效果最好,TP的去除率可在65%以上。

净水厂生产废水回收再利用研究

挖掘净水厂生产废水的利用潜力,对其进行合理回用可节约淡水资源,同时具有保护环境的优点,有利于水资源的可持续发展。从安全性来考虑,生产废水处理后再回用是未来发展的必然趋势。生产废水处理方法中最常用的是混凝沉淀法,效果最好的是膜处理方法。膜处理法需控制好膜污染问题且成本偏高,随着膜构件价格逐渐降低,该技术将得到更广泛的应用。

Test Research on the Treatment of Rectifier Diode Production Wastewater from a Company

Rectifier diode production wastewater that contains acid,alkali and heavy metal ions in a company was treated by using neutralization/coagulation sedimentation method.Firstly,pH of wastewater was adjusted via neutralization reaction,and then heavy metal ions(Cu^(2+),Cr^(2+)and Pb^(2+))were removed by adding coagulant PAC and flocculant PAM.Different acid-alkali neutralization reactions were conducted under the process condition to analyze and compare their neutralization effects.The results showed that removal rates of heavy metal ions were high after coagulation test:Cu^(2+),Pb^(2+)and Cr^(2+)contents dropped from 13.230,0.032,and 1.720mg/L to 0.3,0.001,and 0.24mg/L;besides,total iron,total manganese and turbidity all had very good removal effects.

钙盐-混凝法处理高氟废水的实验研究

含氟废水会对环境造成巨大危害,但传统钙盐法难以实现含氟废水达标排放。为解决某光伏企业的高氟废水处理问题,本研究对实际生产废水进行研究,确立了一级钙盐联合二级混凝的工艺路线,并对高氟废水进行单因素实验和正交试验,以钙盐种类及投加量、反应pH、混凝剂种类为变量,以出水残氟质量浓度为考察指标,为工程应用确定了一种合适的除氟工况。结果表明,影响除氟效果的因素依次为钙氟物质的量比>二级混凝反应pH>复合除氟剂(DAMW-03)用量>一级钙盐反应pH。最优除氟工况为:一级钙盐反应以CaCl_2为钙源,钙源投加量为理论钙氟物质的量比(0.5)的1.25倍以上,并使用Ca(OH)_2调节pH=8;二级混凝反应可添加50 mg/L PAC或复合除氟剂(DAMW-03),控制pH在5~7,最终可实现中性出水且出水ρ(F^(-))可稳定小于5 mg/L。一级钙盐法联合二级混凝法可使高氟废水稳定达标排放,具有处理效率高、试剂易得、处理成本较低等优点。