浅析某厂化学镀镍线的主要污染物及处理措施

某厂化学镀镍线产生的主要污染物为大气污染、水污染和固体废物污染。其中大气污染物主要为硫酸雾。水污染物为总镍、总铜、化学需氧量、悬浮物、总磷、氨氮等。固废废弃物均为危险废物,包括废包装材料、酸性废液、含镍废液。该文分析了化学镀镍线产生的废气、废水和固体废物的主要来源,并提出了防止污染的对策。     

破络合剂对化学镀镍废水处理的影响

采用不同的破络合剂处理化学镀镍废水,探讨了CaO、CaCl2和BaCl2 3种破络合剂处理化学镀镍废水时,对Ni2＋去除率的影响,同时对CaO联合BaCl2处理化学镀镍废水进行了研究。实验结果表明,CaO、CaCl2和BaCl2的使用量分别为3.0、6.0和4.5 g/L时,Ni2＋去除率分别为32%、19%和99.9...     

活化煤吸附火箭燃料剂废液的处理试验

液体火箭燃料剂混胺—02,是有毒物质,不允许其废液直接排放。据文献介绍,可采用漂白粉或高锰酸钾溶液处理,但该法缺点是要消耗一定量的氧化剂,显然不经济,反应有时只氧化掉二、三乙胺,其中的异构二甲苯胺     

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。     

破络-Fenton法处理化学镀镍废水并回收水中的磷酸盐

以电镀厂化学镀镍的混合清洗水为处理对象,采用CaO破络吸附联合Fenton氧化的多级物化技术去除废液中的镍离子和磷酸盐,研究CaO投加量和反应时间对镍离子去除效率的影响以及Fenton试剂投加量、反应初始pH对废液中磷处理效果的影响。结果表明,通过两段式反应,当CaO投加量为2 g·L~(-1)、反应时间1 h;反应初始pH为4、H_2O_2投加量9.18 mg·L~(-1)、m(H_2O_2)/m(Fe~(2+))为5∶1、反应时间180 min时,镍离子和总磷(TP)含量由原来的64.6和90.2 mg·L~(-1)分别降低至0.43和0.46 mgl·L~(-1),均达到国家《污水综合排放标准》(GB 8978-1996)。处理后沉淀物经测试符合Fe_2(PO_4)_3晶体及其形貌特征,达到了资源回收的目的。     

利用纯碱厂三碱性废液进行烟气脱硫（FGD）工艺试验研究

纯碱厂在生产纯碱过程中要排放出大量碱性废液,如果利用其作为净化锅炉烟气的脱硫剂,不仅减低了脱硫剂费用,而且消除了SO2污染。本文在简单分析旋流板塔式除尘脱硫装置的结构和工作原理的基础上,探讨了利用碱性废液进行烟气除尘脱硫的太要影响因素,并找出了最佳操作条件。试验结果表明：利用纯碱厂排放的碱性废液－一次盐泥进行锅炉烟气脱硫可以取得较高的净化效率,同时解决了因为碱性废液排放而给周围水域带来的污染。旋流板塔式除尘脱硫装置结构简单,脱硫效率高,并且运行安全稳定,是一项值得推广的技术。     

利用纯碱厂碱性废液进行烟气脱硫(FGD)工艺试验研究

纯碱厂在生产纯碱过程中要排放出大量碱性废液 ,如果利用其作为净化锅炉烟气的脱硫剂 ,不仅减低了脱硫剂费用 ,而且消除了SO2 污染。本文在简单分析旋流板塔式除尘脱硫装置的结构和工作原理的基础上 ,探讨了利用碱性废液进行烟气除尘脱硫的主要影响因素 ,并找出了最佳操作条件。试验结果表明 :利用纯碱厂排放的碱性废液———一次盐泥进行锅炉烟气脱硫可以取得较高的净化效率 ,同时解决了因为碱性废液排放而给周围水域带来的污染。旋流板塔式除尘脱硫装置结构简单 ,脱硫效率高 ,并且运行安全稳定 ,是一项值得推广的技术     

膜电解工艺处理碱性含铜蚀刻废液

实验对碱性含铜蚀刻废液膜电解工艺处理的可行性开展相关研究,考察了槽电压、电解时间和阳极液pH值等因素对膜电解电流效率的影响,并确定了最佳工艺条件:槽电压3.10 V、电解时间2 h、阳极液初始pH值9.20。在上述最优工艺条件下,膜电解电流效率达91.5%。实验结果表明,该工艺操作方便、简单可行,是处理蚀刻废液、回收铜的有效方法,具有一定的应用价值。     

化学镀镍废水中磷和镍的同步去除

为有效去除化学镀镍废水中的主要污染物质磷与镍,采用H_2O_2氧化、芬顿氧化、铁碳处理、次氯酸钙氧化4种方法进行同步除磷去镍效果研究。结果表明:H_2O_2可有效去除废水中的镍,但单独氧化除磷效果不佳,芬顿氧化可增强其对磷的去除率,在一定的反应时间下达到良好的同步除磷去镍的效果;铁碳处理可基本达到同步除磷去镍的效果,但反应时间长;次氯酸钙可快速去除水中的磷与镍,是一种理想的同步除磷去镍试剂。通过分析可知,4种方法对化学镀镍废水中的磷与镍的去除均具有一定效果,且各具优势。研究为实现化学镀镍废水中同步除磷去镍的目标提供参考。     

洗像废液的分质处理

对洗像过程中产生的洗像废液按照成分的不同进行分质处理。其中 ,有机废液采用高温焚烧的方法进行处理 ;无机废液根据主要成分的化学性质分别采用中和、氧化等方法进行处理。通过室内试验 ,确定了处理工艺的主要参数 ,并根据试验结果 ,利用废液处理站设施处理了 1.6 4t洗像废液。处理后排放的废水、废气均达到了国家有关排放标准     

酸-碱处理对剩余污泥水解酸化的影响

剩余污泥中富含有机质和营养元素可回收利用物质,污泥水解酸化液中的有机酸在去除或回收利用氨和磷后可作为进水化学需氧量(COD)不足的污水处理厂的补充碳源。通过控制pH,对比分析了不同处理方式(单独碱处理、酸-碱处理和碱-酸处理)对污泥水解酸化的影响。结果表明,单独碱处理的溶解性化学需氧量(SCOD)溶出量比酸碱联合处理要大16%左右,预处理第8天,达到5 406.1 mg/L。采用先酸(pH 4.0,4 d)后碱(pH 10.0,4 d)预处理,乙酸产量达到74.4 mg COD/g VSS,占总SCFAs的60.5%,产量及其占总短链脂肪酸(SCFAs)百分比含量均高于其他预处理方式。且酸-碱处理方式下NO4+-N和PO34--P溶出要优于其他处理方式。而单独碱处理方式下污泥减量效果最好,VSS去除率为36.6%。     

Catalytic dechlorination of monochlorobenzene with a new type of nanoscale Ni(B)/Fe(B) bimetallic catalytic reductant

A unique type of nanoscale Ni(B)/Fe(B) bimetallic catalytic reductant was prepared and used for dechlorination of monochlorobenzene (MCB). The sample Ni(B)/Fe(B) was synthesized by an electroless plating method, in which nanoscale Ni(B) was deposited on the surface of nanoscale Fe(B) synthesized by chemical reduction. The results suggest that the nanoscale Ni(B)/Fe(B) bimetallic catalytic reductant has higher dechlorination efficiency than Ni/Fe(B) catalytic reductant prepared by replacing Fe(B) with Ni(2+) in aqueous solution. The Ni content was found to be an important factor in catalytic dechlorination, with the dechlorination rate increasing with Ni content. The electroless plating method improve the efficiency of the Ni(2+) in the solution. Dechlorination takes place with the existence of nanoscale Ni(B)/Fe(B) bimetallic catalytic reductant via a pseudo-first-order reaction.     

铝业碱性赤泥的悬浮碳化法脱碱工艺研究

研究探讨了碱性废弃物赤泥的常压悬浮碳化法脱碱绿色环保新工艺。详细研究考察了反应温度、反应时间、液固比以及CO₂通气量4个因素对赤泥脱碱效能的影响，确定了最佳工艺参数和技术条件。研究表明，在温控60℃，反应时间1.5 h，液固比为10，CO₂通气量为0.8 L/min的反应条件下，赤泥脱碱率（以Na₂O计）达到85%以上，同时得到含3%～5%碳酸盐的碱性溶液。与传统生石灰脱碱工艺相比，悬浮碳化法具有操作简便、脱碱率高、所得碱纯度高，无废弃物排放等优点，并可实现双废物(CO₂废气和赤泥废弃物)的可持续综合利用。     

Electrocatalytic hydrodechlorination of 4-chlorobiphenyl in aqueous solution using palladized nickel foam cathode

The electrocatalytic hydrodechlorination of 4-chlorobiphenyl on palladized nickel foam with high porous structure in an aqueous solution containing MeOH, bromide of hexadecyltrimethylammonium (CTAB), sodium acetate, and acetic acid were investigated in a membrane-separated flow-through cell. The Pd/Ni foam electrode was prepared by electroless deposition method, on which the Pd particles dispersed finely over Ni foam surface indicated by SEM-EDX analysis. The effects of current density, organic cosolvent, initial concentration, temperature, and flow rate on the hydrodechlorination of 4-chlorobiphenyl were examined. Methanol was among the best cosolvents and was used in preferential concentration of 50 vol%. Moderate current density (e.g., 2.23 mA cm(-2)), relatively high initial concentration, temperature, and flow rate were beneficial to improve the hydrodechlorination of 4-chlorobiphenyl. The current efficiencies for the conversion of 1mM 4-MCB decreased with increasing current density and range from 37.2% at 0.74 mA cm(-2) to 14.1% at 5.21 mA cm(-2) after 20 min electrolysis cut. Under the optimized conditions, 1mM of 4-MCB could be removed rapidly with the rate of 94.6% after 2h electrolysis, which gave current efficiencies and energy consumptions in range of 8.1-24.6% and 1.7-5.2 kW h kg(-1), respectively.     

Sorption of copper and nickel by spent animal bones

Animal bone is able to adsorb copper and nickel ions from their single aqueous solutions. It was noted that a decrease in the sorbent concentration with constant copper or nickel concentration, or an increase in the copper or nickel concentration with a constant sorbent concentration resulted in a higher metal loading per unit weight of the sorbent. Increase in the initial pH of the metal solution resulted in an increase in the metals uptake per unit weight of the sorbent. Freundlich isotherm model was found to be applicable for the experimental data of Cu2+ and Ni2+. The results showed that animals bones can be used for the adsorption of the Cu2+ and Ni2+ with higher affinity toward Cu2+ ions. The new sorbent was able to decrease copper concentration to a limit lower than the limit permitted by the environmental regulations.     

超/亚临界水中四溴双酚A的脱溴降解特性研究

在超/亚临界水及其碱溶液中对四溴双酚A进行了水热脱溴降解研究。考察了温度、时间和碱类型对降解特性的影响。结果表明,在纯水中温度是影响四溴双酚A降解的关键参数,350℃下反应180 min和400℃反应30 min,脱溴率分别达到98.7%和96.7%,降解产物中苯酚和4-丁基苯酚分别占50%和20%以上,另外还有少量的烷基酚;向反应体系中加入碱不仅可以中和反应过程中产生的氢溴酸以保护超临界反应釜,而且可以在较低温度下实现高的脱溴率,产物中苯酚含量达50%以上、4-异丙烯基苯酚占10%左右,可以实现脱溴同时回收化工产品的目的。与传统的热解技术相比,超/亚临界水处理TBBPA具有明显的优势,本研究为含溴电子废弃物的清洁高附加值资源化利用提供了一条新的途径。     

采用零排放新工艺处理蚀刻废液

广州市某化工厂开发出一套对线路板蚀刻废液进行大规模集中资源化处理的零排放处理新工艺,该工艺通过在固相条件下生成氧化铜并用重力分选的方法将其分离出来,克服了原有工艺的缺陷,使废液中所有的成分能够在较低的处理成本下全部分离回收,无三废排出,达到了清洁生产的要求.对其工艺条件进行深入研究,通过正交试验优化了工艺条件.     

Repeated use of two Chlorella species, C. vulgaris and WW1 for cyclic nickel biosorption.

Two living Chlorella species were used to remove nickel from solution containing 30 micrograms Ni ml-1 in 10 successive cycles. The present study also examined the continued viability of these two algal species after repeated exposure to nickel. The two species of Chlorella were Chlorella vulgaris (commercially available) and WW1 (indigenous species isolated from domestic sewage and was tentatively identified as Chlorella miniata). The nickel removal percentage of WW1 cells was maintained at around 85% in the first five cycles, then declined slightly from the fifth cycle onwards, and finally achieved around 70% removal at the end of the 10th cycle. On the contrary, the removal efficiency of C. vulgaris declined from 50 to 30% during the 10 cycles of nickel bisorption. At the end of these 10 successive cycles, WW1 accumulated a substantial amount of Ni2+ (the cumulative cellular Ni concentration was 0.92% dry w.), while the value was only 0.17% in the case of C. vulgaris. These results suggest that the local isolate, WW1, had more consistent and satisfactory ability for removing Ni than the commercial C. vulgaris. Both algal species were still capable of dividing after each nickel treatment cycle, suggesting that the cells were not killed even when significant amounts of nickel were adsorbed/absorbed. However, Ni exposure adversely affected the physiological activity of algal cells as reflected by the decline in division rate and chlorophyll-a activity in both species. Such negative effects became more obvious as the number of cyclic treatments was increased. Nevertheless, WW1 cells appeared to recover from nickel treatment when re-cultivated in commercial medium for 2 weeks.     

Characterization of spent nickel–metal hydride batteries and a preliminary economic evaluation of the recovery processes

Valuable metal materials can be recovered from spent nickel–metal hydride (NiMH) batteries. However, little attention has been paid to the metal compositions of individual components of NiMH batteries, although this is important for the selection of the appropriate recycling process. In this study, NiMH batteries were manually disassembled to identify the components and to characterize the metals in each of these. A preliminary economic analysis was also conducted to evaluate the recovery of valuable metals from spent NiMH batteries using thermal melting versus simple mechanical separation. The results of this study show that metallic components account for more than 60% of battery weight. The contents of Ni, Fe, Co, and rare earth elements (REEs) (i.e., valuable metals of interest for recovery) in a single battery were 17.9%, 15.4%, 4.41%, and 17.3%, respectively. Most of the Fe was in the battery components of the steel cathode collector, cathode cap, and anode metal grid, while Ni (>90%) and Co (>90%) were mainly in the electrode active materials (anode and cathode metal powders). About 1.88 g of REEs (Ce, La, and Y) could be obtained from one spent NiMH battery. The estimated profits from recovering valuable metals from spent NiMH batteries by using thermal melting and mechanical processes are 2,329 and 2,531 USD/ton, respectively, when including a subsidy of 1,710 USD/ton. The findings of this study are very useful for further research related to technical and economic evaluations of the recovery of valuable metals from spent NiMH batteries. Implications: The spent nickel–metal hydride (NiMH) batteries were manually disassembled and their components were identified. The metals account for more than 60% of battery weight, when Ni, Fe, Co, and rare earth elements (REEs) were 17.9%, 15.4%, 4.41%, and 17.3%, respectively, in a single battery. The estimated profits of recovering valuable metals from NiMH batteries by using thermal melting and mechanical processing are 2,329 and 2,531 USD/ton, respectively, when including a subsidy of 1,710 USD/ton. These findings are very useful to develop or select the recovery methods of valuable metals from spent NiMH batteries.