钢渣预处理含铬废水及其废渣与铬渣的固化

用钢渣对含铬废水进行预处理，探讨了钢渣粒度、用量、废水pH值和添加硫酸亚铁还原剂的影响。结果表明，经硫酸亚铁还原处理后再用钢渣处理比单纯用钢渣处理的效果明显提高，采用钢渣／总铬质量比为40的100目钢渣处理经硫酸亚铁还原后的含铬废水，总铬和Cr^6＋去除率分别达79％和84％，采用钢渣柱进行的两级淋滤实验进一步表明该方法可作为工业上含铬废水处理的预处理段。处理后的废钢渣同工业铬渣一起进行水泥固化，标准养护20d后固化体表面Cr^6＋浸出率、破碎至5mm粒径以下和酸雨淋溶下的浸出液Cr^6＋浓度均符合安全标准，可作为普通建材或进行填埋处置。     

还原法处理电镀废水后铬反弹成因分析与对策

从化学热力学和电化学理论出发，结合目前普遍采用的还原——固体分离法处理含铬废水工艺，对固液分离后的上清液和沉降污泥Cr^6 含量以及Cr^3 ～Cr^6 之间的形态转化相关性进行研究和分析，进而提醒人们要特别注意控制含铬污水中铬反弹及全过程处理的完整性。     

柱生物曝气法吸附处理含铬废水

利用复合生物吸附剂FY01与活性污泥作为吸附材料，探讨了柱式生物曝气法对高浓度含铬电镀废水的生物吸附效果。研究结果表明，FY01性能稳定，耐进水pH冲击能力较强。当进水pH=2—5、流速为500mL／h时，10gFY01和5g活性污泥联合处理60．4mg／L含铬电镀废水2h后，铬的去除率达78％以上；在4℃冰箱和23—28℃实验室保存50d的FY01对铬的去除分别在78％～83％和77％-84％之间。柱式生物曝气吸附法对含铬废水的处理效果理想，运行稳定。串联处理2000mL总Cr、Cu^2＋和COD浓度分别为60．4、4．51和48．2mg／L的电镀废水2h后，去除率分别高达92．1％、99．2％和71．4％。     

木屑和花生壳吸附去除水溶液中Cr^3＋的试验研究

以废弃物木屑和花生壳作为吸附剂，进行了吸附去除水中Cr^3＋的试验。研究了溶液pH值、初始Cr^3＋浓度以及温度等因素对这2种吸附剂去除Cr^3＋作用的影响，对吸附曲线作了线性拟合，确定了相应的平衡吸附率，在Cr^3＋初始浓度为1、5、10和20mg／L时，木屑对Cr^3＋的平衡吸附率为81％、68％、56％和40％，花生壳依次为77％、63％、53％和42％，并探讨了这2种吸附剂对溶液中Cr^3＋的吸附机理。     

柱生物曝气法吸附处理含铬废水

利用复合生物吸附剂FY01与活性污泥作为吸附材料,探讨了柱式生物曝气法对高浓度含铬电镀废水的生物吸附效果.研究结果表明,FY01性能稳定,耐进水pH冲击能力较强.当进水pH=2～5、流速为500 mL/h时,10 g FY01和5 g活性污泥联合处理60.4 mg/L含铬电镀废水2 h后,铬的去除率达78%以上;在4℃冰箱和23～28℃实验室保存50 d的FY01对铬的去除分别在78%～83%和77%～84%之间.柱式生物曝气吸附法对含铬废水的处理效果理想,运行稳定.串联处理2000 mL总Cr、Cu2 和COD浓度分别为60.4、4.51和48.2 mg/L的电镀废水2 h后,去除率分别高达92.1%、99.2%和71.4%.     

微波辐射回用活性炭对水中亚甲基蓝和Cd2＋去除效果的研究

考察了微波-活性炭联合处理技术对模拟染料废水中亚甲基蓝和Cd2＋的去除效果。对于100 mL浓度为1 000 mg/L的亚甲基蓝溶液、活性炭用量为10 g时,新活性炭对亚甲基蓝的去除率为99.99%;采用700 W微波对吸附亚甲基蓝的活性炭辐射10 min进行再生并回用,经微波辐射再生10次后活性炭对亚甲基蓝的去除率为99.68%,未经微波作用反复使用10次的活性炭对亚甲基蓝的去除率为85.41%。结果表明：微波处理有效地减缓了活性炭吸附能力的下降速率,实现了活性炭再生和反复使用。在吸附过程中,Cd2＋使活性炭对亚甲基蓝的吸附能力略有下降,而共存的亚甲基蓝则促进了活性炭对Cd2＋的吸附,对新炭和再生后活性炭物理化学特性的表征证明了活性炭对亚甲基蓝的吸附为物理吸附,对Cd2＋的吸附为化学吸附。     

载钛活性炭电吸附去除Cr(Ⅵ)的研究

采用sol-gel法制备了载钛活性炭,并用于电吸附处理含铬废水.当Cr(Ⅵ)初始浓度为20 mg/L时,载钛活性炭上施加1.2 V的正向电压,电吸附3 h后的处理水水质满足国家排放标准.研究了载钛活性炭电吸附去除Cr(Ⅵ)的影响因素及TiAC的电脱附再生.     

膨润土对Pb^2＋、Cu^2＋、Cr^3＋的吸附动力学及等温线研究

研究所用膨润土的主要成分为SiO2和Al2O3，属于Ca基膨润土，BET表面积为50．83m^2／g。在恒温及恒定pH条件下，用静态吸附法研究了膨润土对Pb^2＋、Cu^2＋、Cr^3＋的吸附特性，结果表明其较好地符合Lagergren二级吸附速率方程，对这3种离子的吸附速率为Pb^2＋〉Cu^2＋〉Cr^3＋。利用3种等温线方程对吸附过程进行拟合，发现利用Langmuir吸附等温方程计算的值与膨润土吸附Pb^2＋、Cu^2＋、Cr^3＋试验数据最为吻合。膨润土对3种金属离子的平衡吸附量为Cr^3＋〉Cu^2＋〉Pb^2＋。     

羧甲基壳聚糖-膨润土复合吸附剂对Cu^2＋、Ni^2＋、Cr^3＋的吸附

用羧甲基壳聚糖和膨润土制备复合吸附剂，研究了复合吸附剂在不同参数下对Cu^2＋、Ni^2＋和Cr^3＋吸附的影响。结果表明，复合吸附剂对Ni^2＋的吸附可以很快达到吸附平衡，而对Cu^2＋和Cr^3＋的吸附分别在30min和180min时达到平衡；且pH值对吸附容量的影响很显著。通过计算不同温度下的热力学参数△G、△H和△S，3种金属的△G〈0，证实这3种金属吸附都是自发过程。Cu^2＋、Ni^2＋和Cr^3＋的吸附等温线较符合Langmuir型；反应动力学都更符合准二级吸附速率方程。     

铁炭还原法预处理硝基苯废水的填料特性及技术经济比较

比较了铁屑/活性炭及铁屑/焦炭掺混,作为反应填料的铁炭还原处理硝基苯废水的处理效果,发现前者的处理效果要优于后者,COD的去除率高20%左右,但是,前者处理成本高于后者。通过将原水直接利用活性炭及焦炭进行吸附试验,以及投加铁盐进行混凝试验,将处理效果与铁炭还原处理（铁屑与焦炭掺混）的效果进行对比,发现利用铁炭还原技术对硝基苯废水进行预处理,具有明显的优越性。     

The regeneration and recycle of chromium etching solutions using concentrator cell membrane technology

The regeneration of chromium (VI) and the recovery of etched copper from chromium etching solutions by electrodialysis is improved by the addition of a concentrator cell in the catholyte chamber. The concentrator media used are ion-exchange resins or activated carbon cloth. The maximum percentages for the regeneration of chromium and recovery of copper in these systems is however less than 80% and 90% respectively because of the competition between the processes of oxidation of Cr(III) and electrodeposition of copper. A novel combination of electrolysis with electrodialysis and concentrator cell technology is developed that achieves 92% chromium regeneration and 90% copper recovery.     

Chromium removal from water by activated carbon developed from waste rubber tires

Because of the continuous production of large amount of waste tires, the disposal of waste tires represents a major environmental issue throughout the world. This paper reports the utilization of waste tires (hard-to-dispose waste) as a precursor in the production of activated carbons (pollution-cleaning adsorbent). In the preparation of activated carbon (AC), waste rubber tire (WRT) was thermally treated and activated. The tire-derived activated carbon was characterized by means of scanning electron microscope, energy-dispersive X-ray spectroscopy, FTIR spectrophotometer, and X-ray diffraction. In the IR spectrum, a number of bands centred at about 3409, 2350, 1710, 1650, and 1300–1000 cm^?1 prove the present of hydroxyl and carboxyl groups on the surface of AC in addition to C═C double bonds. The developed AC was tested and evaluated as potential adsorbent removal of chromium (III). Experimental parameters, such as contact time, initial concentration, adsorbent dosage and pH were optimized. A rapid uptake of chromium ions was observed and the equilibrium is achieved in 1 h. It was also found that the adsorption process is pH dependent. This work adds to the global discussion of the cost-effective utilization of waste rubber tires for waste water treatment.     

ZH-02树脂对水中腐殖酸的吸附去除研究

通过几种吸附树脂ZH 0 0、ZH 0 1、ZH 0 2、ZH 0 3、颗粒活性炭 (GAC)和AmberliteXAD 4对腐殖酸的静态吸附试验的筛选结果 ,发现大孔树脂ZH 0 2对腐殖酸具有较好的吸附效果。利用颗粒活性炭作为参照 ,探讨了ZH 0 2的动态吸附去除效果和脱附再生条件 ,发现常温下醇碱溶液效果较好。     

Removal of hexavalent chromium of contaminated soil by coupling electrokinetic remediation and permeable reactive biobarriers

Purpose

In this study, a novel and ecological alternative have been developed to treat soils contaminated with hexavalent chromium coupling two well-known systems: electrokinetic remediation and permeable reactive biobarriers. The electric field promotes the electromigration of the hexavalent chromium oxyanions towards the anode. The biobarriers were placed before the anode electrode, in order to promote the reduction and retention of the chromium migrating in its direction. Thus, this technology provided a global treatment to soil removal without subsequent treatments of the contaminated effluents.

Methods

The electrokinetic system was coupled with two different permeable reactive biobarriers composed by Arthrobacter viscosus bacteria, supported either in activated carbon or zeolite. An electric field of 10?V was applied and two different treatment times of 9 and 18?days were tested.

Results

Removal values of 60% and 79% were obtained when electrokinetic treatment was coupled with zeolite and activated carbon biobarriers, respectively, for a test period of 18?day. The reduction of hexavalent chromium to trivalent chromium was around 45% for both systems.

Conclusions

In this work, two types of biobarriers were efficiently coupled to electrokinetic treatment to decontaminate soil with Cr(VI). Furthermore, the viability of the new coupling technology developed (electrokinetic?+?biobarriers) to treat low-permeability polluted soils was demonstrated.     

Adsorption Characteristics of Activated Carbon and XAD4 Resin for the Removal of Hazardous Organic Solvents

A comparative study has been conducted on adsorption/desorption of six hazardous organic vapors on synthetic resin (XAD4) and activated carbon, using a differential reactor involving the expansion of a quartz spring. While both sorbents can effectively remove the organic vapors, it was observed that at low concentrations activated carbon adsorbed more organic vapor than synthetic resin. At higher, industrial concentrations, the resins adsorbed more vapor as demonstrated by the slopes of the equilibrium isotherms. The resin also showed much higher desorptlon.

The effective Intraparticle diffusion coefficients (D_e) were observed to be strongly dependent on solute concentration. Pore diffusion dominated the adsorption/desorption of the six organic vapors on XAD4 resin. For the carbon system, pore diffusion dominated the adsorption but surface diffusion contributed to the desorptlon process. This is believed to be due to higher Interaction of the adsorbates with activated carbon.     

铬离子对SBR工艺活性污泥毒性作用研究

针对重金属铬离子对SBR工艺系统中活性污泥的毒性作用,通过检测不同初始污泥容积指数(SVI)下SBR工艺活性污泥在不同铬负荷下的COD值、挥发性污泥浓度以及受铬离子影响的污泥容积指数(SVI),研究重金属铬离子对活性污泥的毒性作用以及对SBR工艺系统处理污水的影响。研究表明,重金属铬离子会导致SBR工艺系统出水COD升高;将铬离子对活性污泥的毒性作用按照挥发性污泥(MLVSS)铬负荷可划分为耐受范围、非耐受范围、细胞失活范围以及细胞分解范围。耐受范围铬负荷低于约30 mg Cr3+/gMLVSS,此范围内铬离子对于活性污泥的毒性作用不大,不致于导致系统出水水质变差;非耐受范围铬负荷在约30~65 mg Cr3+/g MLVSS,在铬离子作用下系统出水COD值明显高于对照系统;细胞失活范围铬负荷在约70~100 mg Cr3+/gMLVSS范围内,SVI大幅下降,微生物部份死亡和失活,出水COD尽管有一些下降,但与进水COD相比差不了多少;细胞分解范围铬负荷在约100 mg Cr3+/gMLVSS以上,微生物大量死亡,部分死亡细胞分解,系统出水COD值因微生物的死亡分解而超出进水COD值,受铬离子影响的系统SVI值大幅度降低。     

活性炭纤维的氧化处理研究

采用静态保干器法测定了活性炭纤维对乙醇、丙酮、N-甲基吡咯烷酮的吸附量.研究了酸氧化处理对活性炭纤维吸附性能的影响,并用电位滴定法确定了活性炭纤维氧化前后表面含氧官能团的变化.结果表明,活性炭纤维对3种吸附质的吸附量均随时间延长而增加,但饱和吸附量及达到饱和吸附的时间因吸附质的不同而不同.氧化处理后,活性炭纤维表面含氧官能团发生变化,对乙醇的吸附量增加18%,而对N-甲基吡咯烷酮的吸附量提高了300%.     

微波辅助-活性炭法处理电厂EDTA锅炉清洗废水可行性研究

采用微波辅助-活性炭法处理电厂EDTA锅炉清洗废水,研究了微波辐射时间、微波功率以及再生次数对活性炭吸附能力的影响,并根据实验结果设计了工艺流程,分析了微波辅助-活性炭法处理电厂EDTA锅炉清洗废水的可行性.研究表明,微波辅助-活性炭法处理EDTA清洗废水的最佳微波辐射时间和微波功率分别为5 min和680 W,微波辐...     

活性炭纤维的氧化处理研究

采用静态保干器法测定了活性炭纤维对乙醇、丙酮、N-甲基吡咯烷酮的吸附量。研究了酸氧化处理对活性炭纤维吸附性能的影响,并用电位滴定法确定了活性炭纤维氧化前后表面含氧官能团的变化。结果表明,活性炭纤维对3种吸附质的吸附量均随时间延长而增加,但饱和吸附量及达到饱和吸附的时间因吸附质的不同而不同。氧化处理后,活性炭纤维表面含氧官能团发生变化,对乙醇的吸附量增加18%,而对N-甲基吡咯烷酮的吸附量提高了300%。     

废棉布制备活性炭影响因素与机理研究

研究了采用磷酸活化法制备废棉布活性炭的工艺条件。研究表明,废棉布活性炭吸附能力随着磷酸浓度、浸渍时间、活化温度和活化时间的增加呈现先增加后减小的趋势。最佳制备条件为:磷酸浓度40%,浸渍时间24 h,活化温度500℃,活化时间30 min。此时制备的废棉布活性炭性能优于商品活性炭。另外,通过对最佳浓度磷酸浸渍的废棉布进行热失重分析,对磷酸活化废棉布制备活性炭机理开展了初步研究,研究表明磷酸活化废棉布制备活性炭过程分为水分蒸发阶段、炭化阶段、过渡阶段、活化阶段和煅烧阶段。