用矿渣处理含镉水的探索试验

用矿渣处理含镉水的探索试验１前言含镉废水常采用化学沉淀、离子交换及吸附等方法进行处理。活性炭吸附法具有比表面积大、吸附能力强、去除效率高的特点，但价格昂贵，所以一般选用风化煤、磺化煤等代用品。我们在实验中发现，高炉矿渣具有良好吸附能力，故对矿渣处理含...     

硒的环境污染特征及其防控技术

从硒的化学性质、毒性与人类健康、污染来源和分布4个方面,综述了硒及其对环境的污染和危害,总结了含硒废水的膜处理技术、共沉淀法、吸附法、化学还原法、生物还原法和人工湿地法的机理、影响因素和优缺点,为后续硒污染特征研究及污染控制技术提供新思路。     

生物接触氧化法(焦炭载体)处理有机废水的生产试验

本文介绍了以焦炭为载体的生物接触氧化法处理含醇、酯、醛、二氯乙烷废水的生产性试验。处理量为100吨/日。近一年的连续试验结果表明,该工艺设备简单、管理方便、负荷高、处理效果较好,而且空气消耗和治理单价低。     

化学沉淀-微滤法处理FGD废水的试验研究

研究了化学沉淀-微滤法工艺处理湿法烟气脱硫（FGD）废水的效果、实际运行中可能出现的膜污染及其解决方法。试验表明，化学沉淀-微滤工艺处理FGD废水，效果好、抗冲击负荷能力强、系统占地小、自控性强、易于操作，但随着系统的运行，污泥浓度会随之增大，从而导致膜污染，必须定期排泥和进行膜清洗。     

化学气浮法处理庆大霉素废液研究

对较难进行固液分离处理的高浓度有机废水——庆大霉素废液,采用化学气浮法处理取得较好的分离效果,分离后的庆大霉素废液固体悬浮物含量可达到国家排放标准,去除率在97%以上。该方法投资小、耗能低、工艺简单、维修方便,但不能有效地去除废液中的可溶性有机物,尚需用生化法作进一步处理。     

改进型石灰混凝法去除城市污水二级出水中有机物的研究

将石灰混凝处理后的沉淀泥渣进行回流，对石灰混凝法进行改进，研究改进后的石灰混凝法对城市污水二级出水中有机物的去除效果。结果表明，活性泥渣回流有利于提高石灰混凝法对城市污水二级出水中有机物的去除。回流位置在石灰投加前、复合絮凝剂投加后，最佳回流量为新泥渣产生量的100％～200％，活性泥渣回流的最佳pH为11．0～11．5；活性泥渣中CaCO3、Mg(OH)2、Fe(OH)3等沉淀物以及有机高分子絮体均有助于提高其对有机物的去除效果，其中Mg(OH)2沉淀物起主导作用；含循环泥渣的活性污泥回流，对有机物的去除效果无明显影响。     

一套国产废塑料自动清洗、粉碎、脱脂、分离设备

前　言 　　回收的废塑料往往要先进行分离,采用的主要分离技术有：密度分离、溶解分离、过滤分离、静电分离和浮游分离等,见下图。日本塑料处理促进协会的水浮选分离装置一次分离率就可达到99.9％以上,美国DOW化学公司也开发了类似的分离技术,以液态碳氢化合物取代水来分离混合废塑料,取得了更佳的效果;美国凯洛格公司与伦塞勒综合技术学院联合开发出溶剂法选择性分离回收技术,该法不需人工分拣,即可使混杂的废旧塑料得到分离,将切碎的废旧塑料加入某种溶剂中,在不同温度下溶剂能有选择地溶解不同的聚合物而将它们分离。     

过氧化氢-亚铁盐氧化法对染料废水的脱色处理

染料废水具有成份复杂、色度高、水量少、大多数污染物为难降解的有机化合物等特点。采用传统的生化处理法很难使其达标排放,特别是脱色问题是染料废水处理的难题之一。通常采用化学混凝法和气浮法进行脱色处理,这对不溶性的染料,如分散染料、硫化染料和还原性染料等有良好的脱色效果,而对水溶性染料,如活性染料、直接     

硫酸盐还原菌原位修复六价铬污染土壤

以FeSO₄化学还原法为对照,开展硫酸盐还原菌原位修复铬污染土壤的田间试验研究。试验结果表明:微生物法处理后,土壤中Cr(Ⅵ)含量从6.48 mg/kg降至0.95 mg/kg,下降率为85.33%,修复后的土地质量符合国家一类建设用地的标准;土壤浸出液中Cr(Ⅵ)质量浓度从0.162 mg/L降至0.004 mg/L,下降率为97.53%;土壤中硫酸根浓度略有降低,硫酸盐还原菌的丰度显著增加。微生物原位修复铬污染土壤的效果好于化学还原法。     

国外动态

催化法生产中含金属离子废水的处理 [10],37—38(1988) 近年来合成了多种氢化和石油化工工艺用的新催化剂,其成分包含各种金属及其氧化物,结果导致废水中重金属的污染程度提高,给工厂的总处理装置带来困难。为了保障生物处理装置的正常工作,在废水进入统一处理装置以前,必须进行有效的预处理。碱处理法是净化含金属的酸性废水的常用方法。处理的目的有两个,即中和水中的酸和沉淀金属。为了最大限度地使金属沉淀,需要在中和之后测定废水的pH。中和后废水的pH最高不超过8.5,这是废水进入明水沟和下水管道的最高允许值。金     

活性焦烟气净化技术及其在我国的应用前景

活性焦烟气净化技术是利用活性焦的吸附、催化功能对烟气进行深度净化的干法处理技术，可达到同时脱硫脱硝的目的。通过加热再生活性焦，可获得高浓度的SO2气体，用于生产硫酸、液体二氧化硫或硫磺，有效回收硫资源。该技术具有流程简单、占地面积小、无二次污染、费用低、应用范围广等特点。从机理、流程及经济可行性等方面对该技术进行了分析。针对我国国情及硫资源状况，提出活性焦烟气净化技术在我国有着良好的应用前景。     

Hydration and leaching characteristics of cement pastes made from electroplating sludge

The purpose of this study was to investigate the hydration and leaching characteristics of the pastes of belite-rich cements made from electroplating sludge. The compressive strength of the pastes cured for 1, 3, 7, 28, and 90 days was determined, and the condensation of silicate anions in hydrates was examined with the ²⁹Si nuclear magnetic resonance (NMR) technology. The leachabilities of the electroplating sludge and the hardened pastes were studied with the multiple toxicity characteristic leaching procedure (MTCLP) and the tank leaching test (NEN 7345), respectively. The results showed that the electroplating sludge continued to leach heavy metals, including nickel, copper, and zinc, and posed a serious threat to the environment. The belite-rich cement made from the electroplating sludge was abundant in hydraulic β-dicalcium silicate, and it performed well with regard to compressive-strength development when properly blended with ordinary Portland cements. The blended cement containing up to 40% the belite-rich cement can still satisfy the compressive-strength requirements of ASTM standards, and the pastes cured for 90 days had comparable compressive strength to an ordinary Portland cement paste. It was also found that the later hydration reaction of the blended cements was relatively more active, and high fractions of belite-rich cement increased the chain length of silicate hydrates. In addition, by converting the sludge into belite-rich cements, the heavy metals became stable in the hardened cement pastes. This study thus indicates a viable alternative approach to dealing with heavy metal bearing wastes, and the resulting products show good compressive strength and heavy-metal stability.     

Mercury flows in a zinc smelting facility in South Korea

To prepare for the international mercury convention, the characteristics of mercury emissions from a zinc smelting facility in South Korea have been reviewed and a material flow analysis (MFA) has been conducted in this research. As inputs into the mercury MFA study, zinc ores and sulfuric acid were examined, whereas wastewater sludge, effluence water, spent catalyst, and emissions from the casting and roasting processes were examined as outputs. Mercury concentrations extracted from end products like zinc ingots, cadmium ingots, and sulfuric acid were then analyzed. Our results showed that the wastewater sludge discharged from the zinc smelting process had a relatively higher concentration of mercury, indicating that the concentration of mercury was further enriched in the wastewater sludge. The wastes discharged through the zinc smelting process should be thoroughly controlled, as results of the MFA showed that approximately 89 % of the mercury contained in the original input was later found in the waste. According to this study, the higher the concentration of mercury within zinc ores at the input stage, the higher is the mercury concentration found in the wastewater sludge at the output stage.     

Evaluation of the use of a sequential extraction procedure for the characterization and treatment of metal containing solid waste

Metal containing wastes like MSWI fly ashes and blast furnace sludge form a major environmental problem as they are polluted with heavy metals. The ash has to be landfilled or can be used as a construction material, but a pretreatment is in general necessary. Washing of the ashes with water in order to dissolve soluble salts or extracting the heavy metals with chemicals are possibilities. Blast furnace sludge contains large quantities of iron and carbon and could be recycled in the blast furnace, if the zinc content were not that high. Using a hydrometallurgical process the zinc can be removed from the sludge particles. In order to evaluate such treatment methods knowledge of the leaching behaviour of the studied material is very important. One of the factors influencing the leaching behaviour is the composition and mineralogy of the solids. A sequential extraction procedure, whereby the material is sequentially leached with different leaching solutions, can be used as an aid to characterize the material and to determine which chemical conditions are needed to obtain a sufficient extraction efficiency. To verify the accuracy of the sequential extraction procedure, a method is tested on MSWI fly ash and evaluated by comparing the results with those of leaching experiments whereby the final pH of the leaching solutions is varied over a wide range. Based upon this evaluation some suggestions for the use of the sequential extraction procedure are made and an adapted procedure is suggested, and applied to a blast furnace sludge.     

Vitrification as an alternative to landfilling of tannery sewage sludge

Due to high content of heavy metals such as chromium, tannery sewage sludge is a material which is difficult to be biologically treated as it is in the case of organic waste. Consequently, a common practice in managing tannery sewage sludge is landfilling. This poses a potential threat to both soil and water environments and it additionally generates costs of construction of landfills that meet specific environment protection requirements. Vitrification of this kind of sewage sludge with the addition of mineral wastes can represent an alternative to landfilling.The aim of this study was to investigate the possibility of obtaining an environmentally safe product by means of vitrification of tannery sewage sludge from a flotation wastewater treatment process and chemical precipitation in order to address the upcoming issue of dealing with sewage sludge from the tannery industry which will be prohibited to be landfilled in Poland after 2016. The focus was set on determining mixtures of tannery sewage sludge with additives which would result in the lowest possible heavy metal leaching levels and highest hardness rating of the products obtained from their vitrification.The plasma vitrification process was carried out for mixtures with various amounts of additives depending on the type of sewage sludge used. Only the materials of waste character were used as additives.One finding of the study was an optimum content of mineral additives in vitrified mixture of 30% v/v waste molding sands with 20% v/v carbonate flotation waste from the zinc and lead industry for the formulations with flotation sewage sludge, and 45% v/v and 5% v/v, respectively, for precipitation sewage sludge. These combinations allowed for obtaining products with negligible heavy metal leaching levels and hardness similar to commercial glass, which suggests they could be potentially used as construction aggregate substitutes. Incineration of sewage sludge before the vitrification process lead to increased hardness of the vitrificates and reduced leaching of some heavy metals.     

Impacts of ultrasound on selective leaching recovery of heavy metals from metal-containing waste sludge

Lab synthesized metal-bearing sludge (LSMS) was used in series of designed lab tests to evaluate impacts of ultrasound on selective separation of heavy metals through acid leaching. The tests eliminated the potential of induced bias generated by utilizing field sludge that were produced from different location sources. The results showed that metal pairs of Cu and Fe, Cu and Cr, and Cr and Fe inside LSMS could be practically separated with one metal being contained in a liquid phase and another in a solid phase through acid leaching processes enhanced by ultrasound. With assistance of ultrasound, the acid leaching demonstrated a more efficient segregation between metals within LSMS than a conventional leaching that doesn’t have ultrasonic enhancement, and the tests provided in a generic means that ultrasonically enhanced acid leaching could cost-efficiently recover heavy metals from metal-containing waste sludge.     

An overview on the production of pigment grade titania from titania-rich slag.

To recover pigment grade TiO2, operating plants all over the world use chemical processes. Slag-based technology is considered to be attractive because of low waste generation and low chemical cost due to high titanium content and is poised to replace the conventional technology. This paper provides a review of the slag-based technology with the specific aim to produce leachable slag and achieving high titania yield from recovered wastes. Leachable oxides of the lower oxidation state, such as TiO and Ti2O3, facilitate the leaching process. However, during smelting these oxides increase the viscosity of the slag. Formation of titanium carbide or carbonitride is also not desirable as it leads to resistance to the leaching of titanium. This report highlights the problems and their possible solutions to obtain leachable slag.     

Gasification of dried sewage sludge: status of the demonstration and the pilot plant

The disposal of sewage sludge from municipal waste water treatment plants is suffering from raising costs.The gasification is an alternative way of treatment, which can reduce the amount of solid residues that must be disposed from a water treatment plant. The produced gas can be used very flexible to produce electrical energy, to burn it very cleanly or to use it for upgrading.The gasification in the fluidised bed and the gas cleaning with the granular bed filter has shown successful operation. A demonstration plant in Balingen was set up in 2002 and rebuilt to a larger throughput in 2010. As a next step a demonstration plant was built in Mannheim and is now at the end of the commissioning phase. Nowadays the product gas is blended with biogas from sludge fermentation and utilized in a gas engine or combustion chamber to produce heat. In the future the process control for a maximized efficiency and the removal of organic and inorganic impurities in the gas will be further improved.     

铁酸锌高温煤气脱硫剂的活性评价及表征

在自制的固定床反应器上研究了铁酸锌脱硫剂的硫化和再生性能。通过BET及XRD等测试手段,对试样进行了物性表征。结果表明：铁酸锌脱硫剂具有稳定、良好的硫化和再生性能,是适合工业化使用的一种高温煤气脱硫剂。     

超重力旋转填料床中络合铁脱硫工艺处理海上油田含硫伴生天然气

采用超重力旋转填料床中络合铁脱硫工艺处理海上油田伴生天然气。运行结果表明：海上油田超重力旋转填料床络合铁脱硫系统投资1 500 万元，设备总占用面积不足48 m²，天然气处理量2×10⁵ m³/d，回收硫磺400 kg/d；进口伴生天然气中硫化氢的质量浓度为2 000~2 500 mg/L，经脱硫处理后硫化氢的质量浓度低于3 mg/L，达到GB 17820—2012《天然气》中硫化氢含量的要求。该工艺解决了海上平台空间紧张、结构承重有限等问题，装置运行稳定，避免了设备腐蚀，运行成本低，运行效果显著，具有良好的经济效益和社会效益。