褐煤灰及改性褐煤灰吸附水中镍离子

用昭通褐煤灰和改性褐煤灰作为吸附剂处理水中重金属离子(Ni2 ),发现改性褐煤灰对金属离子具有良好的脱除效果.考察了接触时间、温度、pH值、溶液中溶质的浓度及吸附剂用量等凶素对Ni2 脱除率的影响.初步探讨了褐煤灰吸附Ni2 的机理.     

制胶工艺讲座——五、骨素的中和

<正> 骨素的退灰、中和、水洗是提高明胶质量的重要因素,其全过程包括对骨素中吸收的石灰,与胶原联结的石灰及碱溶性非胶原蛋白质的充分退碱。中和、水洗影响到胶原质量、明胶理化性能及增感剂、抑制剂、金属离子等含量,这与照相明胶的照相性能有十分密切的关系。一般,骨素中各种杂质的大量除去,可以在浸灰处理后经过充分洗涤和酸性脱灰过程中做到。因此,掌握好中和的技术,对明胶的质量有着重大意义。     

硫酸净化污酸资源化利用初探与实施

介绍了污酸资源化利用技术方案,其中包括减少悬浮物,脱除部分重金属;脱除净化流程稀酸中的氟、氯离子;降低污酸中金属与非金属离子等。该技术减少了污酸外排量、石膏渣量和中和渣量,中和渣锌品位得以提高,深度脱除污酸滤渣中的汞、硒,使之得以富集,提高了外销经济价值,降低了环境风险。     

拜耳法赤泥不同脱碱工艺的对比分析

赤泥是氧化铝冶炼工业中排放的强碱性固体废弃物,为了降低赤泥中碱的含量,实现赤泥综合利用,对二氧化碳浸出法、酸中和法、钙离子置换法等脱碱工艺进行了初步的对比研究。结果表明,二氧化碳浸出法能够降低赤泥浆的pH,并有效去除赤泥中的钠（I）;盐酸的加入可以大幅度降低赤泥浆的pH,进一步水洗虽然能基本去除赤泥中的钠（I）,但pH会增加;钙化合物的添加能有效置换出赤泥中的结合碱,但对赤泥浆pH的影响不大。     

提高重质纯碱产量的途径

根据现有重灰生产条件，提高通过降低一水碱游离水，达到既提高重灰炉生产能力，又可解决蒸汽量和化合水不足的问题，使重灰产量提高２５％。     

氢氧化镁在环保领域中的应用

氢氧化镁被称为"环境友好型"的环保处理剂,近年来得到了广泛的应用,主要包括:酸性废水中和、重金属离子脱除、烟气脱硫、印染废水处理等.本文对氢氧化镁在环保领域中的应用进行了综述.     

整流二极管生产废水处理试验研究

采用中和-混凝沉淀工艺处理某公司生产整流二极管含酸碱、重金属离子废水。首先通过中和反应调节废水pH值,分析对比了不同的酸碱中和反应的效果;再通过加混凝剂(PAC)和絮凝剂(PAM),去除其中的重金属离子。结果表明,经过混凝试验后的重金属离子去除率很高,铜离子的质量浓度由原水的13.23 mg/L降到了0.30mg/L左右;铅离子的质量浓度由原水的0.032 mg/L降到了0.001 mg/L;铬离子的质量浓度由原水的1.720 mg/L降到了0.240 mg/L左右;对总铁、总锰以及浊度都有很好的去除效果。     

中和在明胶生产中的作用

前言 骨素的中和工序,即骨素的退灰、中和退酸是骨素转变成明胶前的最后一个工序,也是提高明胶质量的重要一环。骨素的退灰、中和退酸,影响着明胶的质量,明胶的理化性能及增感剂、抑制剂、金属离子含量等,这些都与照相性能有十分密切的关系。骨素中杂质可以在浸灰过程中通过充分水洗而大量除去,而浸灰产生的酸溶性杂质,只有通过有效的中和过程来除去,因此明胶生产的中和工序在明胶生产     

重灰的筛分

介绍了重灰的筛分在重灰生产中的作用、几种碱筛的结构及特点,并对如何提高碱筛的筛分能力进行了探讨,以进一步提高重灰装置的生产能力。     

重铬酸钠母液脱除杂质 提高母体及联产品质量

重铬酸钠母液循环利用，会造成氯离子及三价金属离子等积累而影响母体及联产品质量。本文介绍氯离子脱除法（包括强酸化法、氧化剂氧化法及电解氧化法），三价金属离子脱除法（包括预酸化法、中和游离酸法）及硅酸根离子脱除法。介绍了除杂工艺流程，并作了技术评价。     

活性污泥吸附重金属离子的研究进展

从处理含重金属离子废水的现状出发,简述了活性污泥吸附重金属离子过程中的表面有机络合、离子交换及其它机理;讨论了温度、时间、pH值、污泥种类、预处理、重金属离子浓度等因素对活性污泥吸附重金属离子的影响,并对解吸方式进行了论述;综述了目前国内外有关活性污泥吸附重金属离子的最新研究成果,指明了进一步加强吸附机理和固定化技术以提高活性污泥应用性的研究是今后的方向。     

不锈钢酸洗废水钙钠中和沉淀与碳热还原协同处理新工艺

通过研究不锈钢酸洗废水体系中氟离子脱除和金属离子沉淀的规律,开发了钙钠协同沉淀新工艺,并对新工艺产生的污泥于1200℃下进行还原,细磨、磁选后得铁、铬、镍合金粉末和再生萤石矿。结果表明,该工艺实现了废水的达标排放,污泥产生量减少了14.79%,实现了铁铬镍的金属化还原,得到了再生萤石矿和金属品位93.62%的合金粉末,合金粉末中铁、铬、镍品位分别达69.31%, 7.60%和16.71%,回收率分别高达95.30%, 88.70%和97.53%。     

Pilot plant investigation on petrochemical wastewater treatmentfor the removal of copper and chromium with the objective of reuse

There has been great demand for development of technologies that remove toxic heavy metal ions from wastewater. Chemical precipitation operation is known to remove heavy metal ions from water. In this study applicability of alkaline reagents such as Ca(OH)₂ (lime) and NaOH (caustic soda) in removing copper and chromium ions were evaluated. Separation of heavy metals such as chromium compounds from petrochemical industries' cooling water wastes was achieved by conversion of hexavalent chromium, Cr(VI), to trivalent chromium, Cr(III). Maximum conversion occurred in the pH range of 2.0 and 2.3, adjusted by ferrous sulfate and sulfuric acid. Maximum precipitation of Cr(III) occurred at pH 8.7 with addition of Ca(OH)₂, followed by mixing and 2-h sedimentation. At the end, the concentration of chromate was reduced from 30 ppm to 0.01 ppm. In the case of copper, which is found in the form of cupro-ammonia in ammonia plant wastes, it was observed that the presence of ammonia in wastewater prevents effective chemical precipitation. Therefore, the quantity of ammonia was reduced by aeration. The optimum aeration rate was determined to be 70 L/min, and it was found that ammonia concentration reached equilibrium after 5.0 h o f aeration. Furthermore, hydroxide and carbonate methods were evaluated with respect to precipitation of heavy metals at bench scale, and the former was selected as the method of choice. The results obtained in the Jar test were then applied to pilot scale, and it was determined that the optimum pH for maximum copper precipitation was about 12.0 for both lime and caustic soda used in the hydroxide precipitation method. Lime was preferred due to economics and its high speed of precipitation. Finally, using established methods described here, the concentration of copper followed by coagulation with lime, mixing, 2-h sedimentation and filtration through Whatman 0.45 Am filters was reduced from 48.51 mg/L to 0.694 mg/L, which is below the environmental standards for water resources.     

Electrodialytic remediation of soils polluted with Cu,Cr, Hg,Pb and Zn

Electrodialytic remediation of heavy metal polluted soil is a method which combines the technique of electrodialysis with the electromigration of ions in the polluted soil. Results from laboratory-scale remediation experiments of soil samples from three real contaminated sites with different heavy metals are presented. In the three cases it was possible to mobilize and reduce the amount of the pollutants in the soil. The pollutants were (1) copper and chromium, (2) mercury and (3) copper, lead and zinc. For a loamy sand polluted with copper and chromium it was possible to decontaminate the soil to an extent lower than the recommended critical values for metal concentration in soil. Parameters that were identified as important for the efficiency of the electrodialytic remediation method were pH in the soil, lime content and speciation of the heavy metal. ©1997 SCI     

含重金属离子废水处理过程中pH值的设定

针对金隆公司两段石灰乳中和法处理含重金属离子酸性废水工艺，分析pH值对污染物沉淀效果的影响：提出一次中和pH控制值设定在6．5，二次中和pH控制值设定在9。生产实践证明，除砷、氟和重金属离子效果很好，废水处理后可达到国家排放标准，并且生产成本较低，中和渣生成量较少。     

Adsorption capacity and removal efficiency of heavy metal ions by Moso and Ma bamboo activated carbons

In order to understand the adsorption capacity and removal efficiency of heavy metal ions by Moso and Ma bamboo activated carbons, the carbon yield, specific surface area, micropore area, zeta potential, and the effects of pH value, soaking time and dosage of bamboo activated carbon were investigated in this study. In comparison with once-activated bamboo carbons, lower carbon yields, larger specific surface area and micropore volume were found for the twice-activated bamboo carbons. The optimum pH values for adsorption capacity and removal efficiency of heavy metal ions were 5.81–7.86 and 7.10–9.82 by Moso and Ma bamboo activated carbons, respectively. The optimum soaking time was 2–4 h for Pb²⁺, 4–8 h for Cu²⁺ and Cd²⁺, and 4 h for Cr³⁺ by Moso bamboo activated carbons, and 1 h for the tested heavy metal ions by Ma bamboo activated carbons. The adsorption capacity and removal efficiency of heavy metal ions of the various bamboo activated carbons decreased in the order: twice-activated Ma bamboo carbons > once-activated Ma bamboo carbons > twice-activated Moso bamboo carbons > once-activated Moso bamboo carbons. The Ma bamboo activated carbons had a lower zeta potential and effectively attracted positively charged metal ions. The removal efficiency of heavy metal ions by the various bamboo activated carbons decreased in the order: Pb²⁺ > Cu²⁺ > Cr³⁺ > Cd²⁺.     

重金属污泥磨细粉对硅酸盐水泥基材料性能的影响

为了更好地实现对重金属污泥的资源化利用,研究了高温无害化处理重金属污泥与建筑渣土混合渣料磨细粉对硅酸盐水泥基材料工作性、力学性能、早期收缩变形、抗氯离子渗透性能及重金属浸出的影响及机理。研究结果表明,随着磨细粉掺量的增加,硅酸盐水泥基材料的工作性没有降低,但其力学性能均有一定程度下降,这说明磨细粉与硅酸盐水泥的需水比相差不大,但其掺量越大水泥基材料中水泥的量越低,其强度均会有一定程度下降。磨细粉不会引起硅酸盐水泥基材料的体积安定性问题,可以提高早期抗裂性,但会降低其抗氯离子渗透性能。含磨细粉试件中重金属的浸出浓度、水胶比的下降与龄期的上升呈负相关,且在28 d龄期下含40%(质量分数)磨细粉的硅酸盐水泥基材料中重金属Cu、Ni、Zn和Cr的浸出量均低于GB 30760—2014《水泥窑协同处置固体废弃物技术规范》规定的浸出浓度限值。     

改善明胶生产废水污染的磷酸氢钙回收工艺

在考察明胶生产工艺、废水水质特性的基础上,提出一改进的磷酸氢钙清洁回收工艺。在浸灰工段后设一沉淀池,沉淀分离石灰沉渣,将上层饱和的氢氧化钙浸灰废液送至浸酸工序,处理浸酸废液,调pH至4.7左右,回收磷酸氢钙。而原工艺是用灰乳处理浸酸废液回收磷酸氢钙,大量饱和Ca(OH)_2浸灰废液外排,造成了难于治理的明胶生产废水高碱、高钙、高悬浮有机物污染。实验证明,该改进工艺能消耗大量的浸灰废液,有效降低明胶生产废水的高碱特性,对悬浮COD的去除效果与使用普通净水剂效果相当,且对磷钙复合肥的收率无重大影响,所排废液不再是饱和的氢氧化钙溶液,钙污染也得到一定控制,与原废水相比生化处理难度大大降低,具有显著的环境效益。     

活性炭载铁催化剂催化臭氧化污泥的研究

以活性炭为载体通过浸渍一焙烧法制备了活性炭载铁（Fe／AC）催化剂,并考察了铁盐种类、煅烧温度、铁盐水溶液中铁离子浓度对催化臭氧化污泥的影响及处理后污泥的相关性质变化。结果表明．采用铁离子浓度为O．20mol·L^-1的FeCl3作为铁盐水溶液、煅烧温度为500℃所制备的活性炭栽铁催化剂催化臭氧化污泥的效果最佳;处理后污泥滤饼的含水率下降近9％,污泥滤液的COD值下降46．39mg·L^-1,污泥的沉降性能优于原污泥,滤液中的铁离子能更好地固化。XRD分析表明活性炭表面所负载的铁氧化物为Fe2O3。     

Colorimetric photonic hydrogel aptasensor for the screening of heavy metal ions

We have developed a robust method for the visual detection of heavy metal ions (such as Hg(2+) and Pb(2+)) by using aptamer-functionalized colloidal photonic crystal hydrogel (CPCH) films. The CPCHs were derived from a colloidal crystal array of monodisperse silica nanoparticles, which were polymerized within the polyacrylamide hydrogel. The heavy metal ion-responsive aptamers were then cross-linked in the hydrogel network. During detection, the specific binding of heavy metal ions and cross-linked single-stranded aptamers in the hydrogel network caused the hydrogel to shrink, which was detected as a corresponding blue shift in the Bragg diffraction peak position of the CPCHs. The shift value could be used to estimate, quantitatively, the amount of the target ion. It was demonstrated that our CPCH aptasensor could screen a wide concentration range of heavy metal ions with high selectivity and reversibility. In addition, these aptasensors could be rehydrated from dried gels for storage and aptamer protection. It is anticipated that our technology may also be used in the screening of a broad range of metal ions in food, drugs and the environment.