用磁选与浮选实现碱洗废液的净化与再用

碱洗是硅钢生产的重要环节。碱洗液随使用时间的延长，其中会累积大量杂质，造成碱液清洗效率下降而失效。本文使用磁选与浮选联合法去除碱液中的杂质，达到了提高碱洗效率并实现碱液的循环再用。     

轧制油泥资源化工艺研究

钢铁和机械加工过程中会使用由润滑油配置而成的乳化液,经过多次循环使用后会混入金属颗粒、胶质、灰尘等杂质,进而形成轧制油泥。轧制油泥属于危险废物,已经成为环保治理的难题。采用碱洗/酸化分离工艺对某机械厂提供的轧制油泥进行处理,进而回收脂肪酸和铁粉,以实现轧制油泥减量和资源化的目的。试验结果表明:在碱液/轧制油泥(质量比)为4、温度为80℃、反应时间为120min、NaOH添加量为轧制油泥皂化值1.05倍的条件下,皂化率和脂肪酸产率分别为87.55%和81.01%,固体残留率为26.48%,经二次碱洗后固体残留率进一步降至8.26%,主要成分为铁粉。碱洗/酸化工艺简洁、成本较低,为轧制油泥规模化处理和利用提供了合理有效的解决方案。     

酚醛缩聚法处理炼油厂高浓度含酚废水（碱渣）的试验研究

一、前言石油炼厂中含酚废水主要来自碱洗汽油催化裂化及常减压工段,其中以反复使用洗涤汽油后的废碱液中含酚量最高,通常称为“碱渣”。该废水中还含有大量硫化物、油状物、碱及无机盐类,历来是各石油炼厂中难以处理而浓度又极高的有毒废水种类之一。目前,国内对该种废水尚无比较成功的处理方法,一般采用萃取法、加浓H_2SO_4提粗酚法、CO_2气提法以及回收碱法,这些方法都存在很多缺陷,如成本高,对设备的腐蚀性严重,酚的去除率很低等。有的厂则不经处理而将其与其他种类的废水混合稀释后排放,严重污染环境。     

印刷用铝基材碱洗废液的循环利用

对印刷用铝基材碱洗废液进行了循环利用研究。首先将高COD含量的碱洗废液进行除油脱色处理，通过石灰和硬脂酸的协同效应，使COD含量从26300mg／L降至480mg／L，色度降至60°；然后利用含铝碱性废液通过碳化法制备出结晶度66％的拟薄水铝石产品；最后对分离后的碱性废水按配方要求配制，对铝基材进行除油实验，经5次循环表明，除油效果和对铝基材的腐蚀率均100％达标。     

农药厂废气污染综合治理系统设计与应用

结合浙江某农药厂废气污染的监测、调查和防治方面的经验,总结了农药厂废气污染特点,并采用吸附、吸收和焚烧等综合治理技术有效控制了废气污染.以该农药厂乙酰甲胺磷、包装车间和污水站为例,对主要废气预处理进行了分析:乙酰甲胺磷车间乙酰脱溶真空泵和反应釜产生的氯仿废气经二级深冷回收后进入活性炭吸附处理系统进行预处理;乙酰真空泵产生的其他废气经二级深冷回收预处理;反应釜、溶剂储槽混合废气经水洗、氧化二级吸收预处理;包装车间和污水站废气各自经碱洗吸收预处理.预处理后的废气采用氧化、碱液二级吸收工艺进行废气集中处理,再经锅炉焚烧后,各类废气排放浓度或排放速率均远低于相应标准限值,可实现达标排放.     

丝光废碱液净化处理工艺研究

为了循环利用牛仔布丝光加工工艺过程产生的废碱液,实验采用臭氧、双氧水以及二氧化锰为净化脱色剂对废碱液进行了脱色净化的研究,结果表明选用的3种脱色剂均有效果,以臭氧效果最佳。因此,重点探讨了臭氧的净化脱色工艺及条件,对于碱浓度为80 g/L的丝光废碱液,当臭氧曝气量为0.25 m3/h、接触反应时间为4 h时,脱色率可达到99.3%,经臭氧净化的废碱液能在牛仔布丝光工艺中循环使用。     

脱硫灰-石灰石湿法脱硫石膏中杂质悬浮分离实验

根据脱硫灰及石膏的特性，在无挡板平底圆筒搅拌槽内，对脱硫石膏中的杂质进行完全离底悬浮分离实验，研究结果表明，完全离底悬浮搅拌时，悬浮高度比越低，越有利于杂质分离。对于直径D≥24cm的搅拌槽，当桨叶离底高度cb=4cm，桨径槽比d／D=0．65，杂质分离效率叼最高，约82％；当直径D=20cm时，杂质分离效率η随d／D的增大而增大，桨叶离底间距减小，杂质分离效率受d／D影响程度减小；当桨叶离底高度cb=4cm时，随着搅拌槽直径D的增大，杂质分离效率总体呈现增大趋势，降低桨叶离底高度cb杂质分离效率变化较大；进行完全离底悬浮分离后，石膏纯度提高。     

丝光淡碱液回用新技术

纯棉、涤棉混纺织物氧氯漂轧染印花生产工艺丝光淡碱液的回收和利用,历来是印染行业和环境保护的重要科技攻关课题.常规的方法是用淡碱液浓缩设备蒸汽加热浓缩回用.多年来广大科技工作者把精力主要放在研制浓缩设备上.但淡碱液浓缩回用法设备投资大,整套设备投资约30多万元人民币,运转费用高,操作复杂,要用电、蒸汽及冷却水等,印染企业较难承受.而该新技术突破常规,一改传统的机械浓缩回用法,大胆采用一次性投资费用低,运行费用少,操作简单,使用安全可靠的直接稀释回用新技术.该新技术不用其它药剂,直接用淡碱液作为原液,配制成退浆、煮炼、皂洗、氧漂、烧毛工段所需浓度的碱液,采用加压管网回路结构,接到各作业工段.工程总投资不到7万元.     

臭氧定量氧化联合湿法吸收同时脱硫脱硝

采用臭氧定量氧化NO,并结合湿法吸收进行脱硫脱硝实验研究。吸收实验选取3种常见碱性吸收液,采用鼓泡法进行NO_x脱除效果对比,最终选定0.05 mol·L~(-1)的Ca(OH)_2乳浊液为吸收液。考察了NO和NO_2不同配比下的吸收效果,当氧化度为60%(NO_2/NO物质的量比1.3)时,吸收效果最佳。臭氧氧化实验结果表明,O_3/NO物质的量比为0.6时能达到最佳氧化度,碱液吸收NO_x脱除效率能达到76%,SO_2脱除效率达100%。当改进鼓泡方式后,最佳氧化度条件下NO_x脱除效率提高到85%。碱液pH对该法脱硝效率有影响,SO_2的存在对NO_x的脱除有一定促进作用。     

对硝基乙苯清洁生产工艺

采用以升温充分静置分酸，洗涤水处理循环使用和碱洗废水加碱套用为核心的对硝基乙苯清洁生产工艺，可以使对硝基乙苯的收率提高5％，成本降低1500元/t，同时很好地解决了对硝基乙苯生产过程中的水污染问题。     

老化石油污染土壤的清洗处理

以华北油田老化长达1年以上的石油污染土壤为研究对象,采用自行选配的清洗剂对该污染土壤进行了一次清洗和二次清洗处理.实验结果表明,一次清洗后,污染土壤样品的含油率从26.34%～29.90%降到6.34%～7.84%,洗油率达80.06%～81.06%;经二次清洗处理后,污染土壤样品的含油率从26.34%～29.90%降到4.05%～4.85%,洗油率达88.06%～88.19%.在一次清洗和二次清洗的基础上,通过模拟实验确定了洗油污水回用的最佳回用率为80%,最佳加药质量浓度为0.4 g/L,该条件下污水的最终产生量也较少.按照该参数对华北油田的石油污染土壤进行了清洗实验,洗油率达79.20%～80.51%.     

表面活性剂清洗处理重度石油污染土壤

为了优化表面活性剂清洗处理重度石油污染土壤的方法和具体洗脱条件参数，采集山东省东营市胜利油田污染土壤，研究了阴离子-非离子混合表面活性剂对该土壤中石油类污染物的去除效果。应用化学热洗原理，主要考查了表面活性剂配比、投加量、清洗温度及清洗助剂对去除效果的影响。实验得到的清洗处理最佳条件为：使用LAS与TX-100质量比为8∶2的组合表面活性剂，总表面活性剂浓度为3 g/L，助剂硅酸钠浓度为5 g/L，75℃条件下搅拌1 h。清洗后土壤含油量从20%下降到4.6%，去除率达到76.9%。废水回用实验表明，清洗处理的废水对土壤中石油烃类物质仍有一定的去除效果。废水回用比从30%到100%时，对土壤中石油烃的去除率都可达到55%以上。对废水进行二次回用时仍能去除18.8%的污染物。     

鼠李糖脂对剩余污泥中铜和镍的去除

采用批次淋洗的方法研究了鼠李糖脂浓度、pH、淋洗时间、提取次数以及重金属形态对剩余污泥中Cu和Ni去除效果的影响。结果表明,随着鼠李糖脂浓度的增加,2种重金属的去除率增加,且鼠李糖脂在碱性条件下对Cu和Ni的去除效果较好,最高去除率可分别高达80.77%和46.74%;随着振荡时间和提取次数的增加,Cu和Ni的去除率随之增加,并明显高于去离子水的提取;对污泥重金属形态进行分析发现,鼠李糖脂能有效去除酸提取态的Cu和Ni。研究结论可为剩余污泥的资源化而产生重金属安全隐患问题提供解决的参考方案和奠定理论基础。     

Displacement and sweep efficiencies in a DNAPL recovery test using micellar and polymer solutions injected in a five-spot pattern

Soil washing with micellar solutions is a promising alternative for the remediation of DNAPL source zones. As with any flushing technology, the success of soil washing with micellar solutions depends in a very large part on the ability of the solution to contact the contaminant (sweep efficiency) and then on the efficiency of contaminant removal once this contact is made (displacement efficiency). We report here on a field test where a micellar solution was used to recover a DNAPL in an open five-spot pattern in which polymer solutions were also injected before and after the washing solution to improve sweep efficiency. The washing solution formulation was optimised in the laboratory prior to the test to obtain good dissolution capacity. For a high-concentration and low-volume soil flushing remediation test such as the one performed (0.8 pore volumes of actual washing solution injected), slug sizing of the washing solution is critical. It was evaluated by an analytical solution. In a five-spot pattern, the displacement efficiency of the washing solution was observed to vary in the porous medium as a function of the radial distance from the injection well because: (1) the volume of the washing solution flowing through a section of the test cell changes (maximum close to the injection well and minimal at the pumping wells); (2) the in situ velocity changes (maximum at the wells and minimum between the wells) and; (3) the contact time of the washing solution with the NAPL changes as a function of the distance from the injection well. The relative importance of the recovery mechanisms, mobilisation and dissolution, was also observed to vary in the test cell. The reduced velocity increased the contact time of the washing solution with the DNAPL enhancing its dissolution, but the decrease of the capillary number caused less mobilisation. The washing process is much more extensive around the injection well. The use of an injection-pumping pattern allowing a complete sweep of the remediated area is essential. Following a comprehensive characterisation, modeling is an efficient tool to design the injection-pumping scheme and to optimise injection and pumping rates providing the best areal sweep. The vertical sweep can be controlled by using a polymer solution (Xanthan gum). The polymer solution also has a positive effect on front stability between the solutions injected. The injection rate of the polymer solution that follows the washing solution must be kept minimal initially to prevent dilution of the washing solution by fingering.     

洗车废水处理技术现状与展望

洗车废水中含有泥砂、油乳化液、有机物及洗涤剂类污染物质。在分析中 ,对洗车废水的水质进行了分类 ,并针对不同的水质 ,对国内的大型洗车场的处理工艺和小型洗车行的洗车废水回用工艺进行了介绍和分析 ,对国外采用膜工艺处理洗车废水的相关研究也进行了简要的介绍 ,同时提出了洗车废水的污泥处理问题。从社会、经济效益来看 ,洗车废水回用是必然趋势。现行的洗车废水回用处理工艺回用率低、处理效果不理想 ,采用高效、简单、实用、经济的原则进行设计 ,满足社会对洗车水回用的需求是未来洗车废水处理技术发展的要求     

Optimizing the molarity of a EDTA washing solution for saturated-soil remediation of trace metal contaminated soils

Three experiments were conducted to optimize the use of ethylenediaminetetraacetic acid (EDTA) for reclaiming urban soils contaminated with trace metals. As compared to Na(2)EDTA, (NH(4))(2)EDTA extracted 60% more Zn and equivalent amounts of Cd, Cu and Pb from a sandy loam. When successively saturating and draining loamy sand columns during a washing cycle, which submerged it once with a (NH(4))(2)EDTA wash and four times with deionised water, the post-wash rinses largely contributed to the total cumulative extraction of Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn. Both the washing solution and the deionised water rinses were added in a 2:5 liquid to soil (L:S) weight ratio. For equal amounts of EDTA, concentrating the washing solution and applying it and the ensuing rinses in a smaller 1:5 L:S weight ratio, instead of a 2:5 L:S weight ratio, increased the extraction of targeted Cr, Cu, Ni, Pb and Zn.     

转轮式洗轮机对车轮带泥的冲洗效果简

施工车辆车轮带泥是我国道路扬尘污染控制面临的共性和突出问题。为在国内推广使用洗轮机提供技术依据，通过检测工地出口外道路积尘负荷来估算转轮式洗轮机对车轮带泥的冲洗效率，并以该洗轮机作为车轮带泥检测设备，检测和统计北京市车轮带泥量。结果表明，（1）转轮式洗轮机可以将工地出口外100 m道路积尘负荷增量由64.4 g/m²降至5.9 g/m²，转轮式洗轮机对车轮带泥的冲洗效率大于90%；（2）渣土车和混凝土车车轮带泥量的平均值分别为5.1和2.2 kg/车；（3）北京市未来车轮带泥量将超过8.8万t/a，施工车辆全部经过转轮式洗轮机冲洗后，车轮带泥量可削减7.9万t/a。建议在相关法律法规中以强制性条款落实施工车辆车轮带泥机械化冲洗要求。     

转轮式洗轮机对车轮带泥的冲洗效果

施工车辆车轮带泥是我国道路扬尘污染控制面临的共性和突出问题。为在国内推广使用洗轮机提供技术依据，通过检测工地出口外道路积尘负荷来估算转轮式洗轮机对车轮带泥的冲洗效率，并以该洗轮机作为车轮带泥检测设备，检测和统计北京市车轮带泥量。结果表明，（1）转轮式洗轮机可以将工地出口外100m道路积尘负荷增量由64．4g／m2降至5．9g／m2，转轮式洗轮机对车轮带泥的冲洗效率大于90％；（2）渣土车和混凝土车车轮带泥量的平均值分别为5．1和2．2kg／车；（3）北京市未来车轮带泥量将超过8．8万t／a，施工车辆全部经过转轮式洗轮机冲洗后，车轮带泥量可削减7．9万t／a。建议在相关法律法规中以强制性条款落实施工车辆车轮带泥机械化冲洗要求。     

Batch washing of cadmium from soil and sludge by a mixture of Na2S2O5 and Na2EDTA

Washing of cadmium contaminated soil and sludge using a mixture of 0.1 M Na₂S₂O₅ and 0.01 M Na₂EDTA was investigated in the batch mode. Initial Cd concentration in samples was 500 mg kg⁻¹. The sequential extraction was conducted to study of what form that Cd was removed. SPSS program version 9.01 was performed to determine what soil parameter had the greatest influence on the washing. The organic matter in soil was found to be the main factor for the washing. Soil with low organic matter would have high percentage of removing Cd. When adding more washing solution, the Cd removal efficiency was lower. The highest removal efficiency was between 67.83% and 97.3% when using a 1 g:2.5 ml soil to washing solution ratio. The predominant form of the removed Cd was exchangeable form. By contrast for the sludge, the highest Cd removal efficiency was 17.13% when using sludge in washing solution at the ratio of 1 g:7.5 ml. Most of washed Cd was in reducible form.     

Reuse of washing effluent containing oxalic acid by a combined precipitation–acidification process

This study aims at evaluating the reuse feasibility of effluent produced by the soil washing of mine tailings with oxalic acid. Alkaline chemicals such as NaOH, Ca(OH)₂, and Na₂CO₃ are used for the precipitation of arsenic and heavy metals in the effluent containing oxalic acid. All of the target contaminants are removed with very high efficiency (up to 100%) at high pH. The precipitation using NaOH at pH 9 is determined to be the most cost-effective method for the removal of arsenic as well as heavy metals in the effluent. The effluent decontaminated by NaOH is consecutively reused for the soil washing of raw mine tailings, resulting in considerable efficiency. Furthermore, even more arsenic and heavy metals are extracted from raw mine tailings by acidifying the decontaminated effluent under the alkaline condition, compared with direct reuse of the decontaminated effluent. Here, the oxalic acid, which is a weak complex-forming ligand as well as a weak acid, has noticeable effects on both soil washing and effluent treatment by precipitation. It extracts efficiently the contaminants from the mine tailings without adverse change of soil and also makes possible the precipitation of the contaminants in the effluent unlike strong chelating reagent. Reuse of the washing effluent containing oxalic acid would make the existing soil washing process more environment-friendly and cost-effective.