熔融铜渣中的金属提取及尾渣制矿棉探索试验

目前铜渣资源化利用主要采用选矿法,处理后仍有大量尾渣无法有效利用。故将铜渣视为含有铜铁金属、高氧化硅无机材料且含高热值的资源,对铜渣进行资源化处理。熔融条件下对铜渣进行还原处理回收含铜铸铁,尾渣用于制备矿棉,实现了熔融铜渣的高附加值利用。该技术处理铜渣产品附加值高、能耗低,且具备一定的市场空间,具有较好的发展前景,可进行推广应用。     

不同粒径零价铁(ZVI)对污水污泥H2S和CH4释放速率的影响

考察了不同粒径零价铁(ZVI),包括200目普通铁粉(200m-ZVI)、800目超细铁粉(800m-ZVI)和纳米铁粉(nZVI,粒径=20 nm),对污水污泥的硫化氢和甲烷释放速率的影响。研究发现:(1)在22 d内,添加0.1%的200m-ZVI使污泥的硫化氢释放速率提高48.0%,而添加0.1%的800-ZVI和nZVI,则使污泥的硫化氢释放速率分别降低33.1%和77.1%;(2)不同粒径ZVI均可以提高污泥沼气中的甲烷浓度,且依次为nZVI>800m-ZVI>200m-ZVI;(3)在23 d内,添加0.1%的200m-ZVI和nZVI使污泥的甲烷累计产生量分别提高了15.5%和40.6%,而添加0.1%800m-ZVI则使甲烷产生量降低了12.5%。nZVI可以有效控制污泥的硫化氢释放,并显著提升污泥在厌氧发酵过程的产甲烷速率。     

Enhanced removal of pentachlorophenol by a novel composite: nanoscale zero valent iron immobilized on organobentonite

Nanoscale zero valent iron (NZVI) was immobilized on the organobentonite (CTMA-bent), so as to enhance the reactivity of NZVI and prevent its aggregation. This novel composite (NZVI/CTMA-Bent) was characterized by transmission electron microscope and X-ray diffraction. Good dispersion of NZVI particles on the bentonite was observed. Its performance on removing pentachlorophenol (PCP) was investigated by batch experiments. Results showed NZVI/CTMA-Bent could rapidly and completely dechlorinate PCP to phenol with an efficiency of 96.2%. It was higher than the sum (54.5%) of reduction by NZVI (31.5%) and adsorption by CTMA-Bent (23.0%) separately. The kinetic studies indicated the removal rate of PCP was positively related to the adsorption. We proposed that the adsorption of PCP by CTMA-Bent enhanced the mass transfer of PCP from aqueous to iron surface. Besides, NZVI/CTMA-Bent exhibited good stability and reusability, and CTMA-Bent could also reduce the amount of iron ions released into the solution.     

超声波／纳米铁协同降解氯代苯酚的试验

通过间歇试验对超声波／纳米铁协同降解氯代苯酚（CPs）废水进行了研究，结果表明，超声波／纳米铁协同对CPs的降解率明显高于单纯超声波和单纯纳米铁的降解率；协同体系、单纯超声波和单纯纳米铁降解CPs均符合准一级反应动力学，协同体系的降解速率较单纯超声波提高了5．1-5．6倍，较单纯纳米铁提高了17．7～21倍，并且比它们的几何迭加值高4倍以上；氯代苯酚降解的准一级速率常数和降解率满足以下规律：PEP〉2，4，5-TCP〉2，4-DCP〉3-CP；探讨了混合废水的降解：在混合废水体系中，结构易裂解的优先降解，然后为浓度高的优先降解。     

改性火山岩滤料去除矿井水中铁锰离子影响因素研究

以改性火山岩滤料作为除铁除锰的滤料,通过对模拟矿井水的过滤试验,研究了滤速、pH值、滤层厚度及铁锰离子浓度对其除铁除锰效率的影响。结果表明：改性火山岩滤料能实现模拟矿井水中Mn²⁺的100%去除,效果明显优于未改性火山岩;最为合理的过滤滤速为7～8 m/h;除铁除锰的过程主要发生在滤层厚度为90 cm的上部滤层中;随着铁锰浓度的升高,改性火山岩滤料除铁的效率变化很小,除锰效率呈快速、线性降低;中性或偏碱性的环境有利于改性火山岩滤料充分发挥高效吸附去除能力。     

酸洗废液制取复合亚铁的研制及应用

介绍了利用酸洗废液为原料制备复合亚铁型混凝剂的新方法 ,并用制得的产品应用于电镀和印染废水治理工程。工程应用及实验结果表明 ,对含Ni2 + 、Cu2 + 和Cr6+ 的电镀废水 ,能使Ni2 + 、Cu2 + 出水浓度 <0 .1mg/L ,Cr6+ 未检出 ,还能处理数种化学镀废液。对印染废水 ,COD去除率和脱色率可分别达到 84 %和 98%以上 ,值得进一步研究和推广     

A sequential zero valent iron and aerobic biodegradation treatment system for nitrobenzene

The remediation of nitroaromatic contaminated groundwater is sometimes difficult because nitroaromatic compounds are resistant to biodegradation and, when they do transform, the degradation of the products may also be incomplete. A simple nitroaromatic compound, nitrobenzene, was chosen to assess the feasibility of an in situ multi-zone treatment system at the laboratory scale. The proposed treatment system consists of a zero valent granular iron zone to reduce nitrobenzene to aniline, followed by a passive oxygen release zone for the aerobic biodegradation of the aniline daughter product using pristine aquifer material from Canadian Forces Base (CFB) Borden, Ontario, as an initial microbial source. In laboratory batch experiments, nitrobenzene was found to reduce quickly in the presence of granular iron forming aniline, which was not further degraded but remained partially sorbed onto the granular iron surface. Aniline was found to be readily biodegraded with little metabolic lag under aerobic conditions using the pristine aquifer material. A sequential column experiment, containing a granular iron reducing zone and an aerobic biodegradation zone, successively degraded nitrobenzene and then aniline to below detection limits (0.5 microM) without any noticeable reduction in hydraulic conductivity from biofouling, or through the formation of precipitates.     

典型钢铁企业VOCs污染特征及SOA生成潜势估算

为了解钢铁企业的大气污染特征,使用在线监测仪器于2016年7月对某典型钢铁企业VOCs（挥发性有机化合物）、PM_2.5和NMHC（非甲烷烃）等污染物进行观测,同时基于FAC（气溶胶生成系数）估算了该区域的SOA（二次有机气溶胶）生成潜势.结果表明:观测期间ρ（总VOCs）为（106.08±63.81）μg/m3,与ρ（NMHC）（以C计）的相关系数（R2）达到了0.8（P < 0.05）以上;VOCs中主要类别为烷烃和芳烃;ρ（O₃）超标期间的ρ（苯）和ρ（甲苯）分别比ρ（O₃）未超标时间段高47.0%和37.2%,并且高ρ（总VOCs）期间芳烃占比高达46.0%,这可能与钢铁企业在炼焦时苯系物（苯、甲苯和二甲苯）排放有关.ρ（总VOCs）、ρ（NMHC）、ρ（烷烃）、ρ（芳烃）和ρ（乙炔）均呈早晚高峰值的日变化特征,而ρ（烯烃）由于异戊二烯受天然源排放影响,呈午间单峰值的特征.观测期间的SOA生成潜势为2.54 μg/m3,较城区高出76.4%,显示钢铁企业SOA对PM_2.5具有一定贡献;其中芳烃对SOA生成贡献高达97.2%,主要贡献组分包括苯、间/对-二甲苯、乙苯、苯、邻-二甲苯.研究显示,钢铁企业VOCs污染治理应重点控制苯系物,同时烷烃的排放也不容忽视.      

Cr元素对铁合金抗热强碱磨损腐蚀性能的影响

测定了10钢、20Cr5、20Cr11含铬铸钢和185Cr13、295Cr26高铬铸铁在85℃的质量浓度为303g蛐L的NaOH溶液中的腐蚀速率、电位鄄时间曲线、静态及冲刷条件下的电化学曲线。实验结果显示,铬钢和铬铸铁在静态浸泡中,电位都经历过高—低—高的变化,表明其腐蚀历程相似。在静态条件下,含铬量高的铬钢和铸铁腐蚀失重大于含铬量低的材料。在冲刷条件下,由失重法获得的总失重和由极化曲线计算得到的腐蚀失重均显示含铬高的铸铁抗磨损腐蚀性能优于含铬量相对低的铸铁。增加铬含量,对合金抗热强碱的纯腐蚀有不利的影响,但却有利于材料抗热强碱介质的磨损腐蚀。     

S-NZVI/PS凝胶反应带修复硝基苯污染地下水

采用前置硫化法合成制备硫化纳米铁,研究其与过硫酸盐对硝基苯的联合降解效果,检测反应前后溶液中铁离子和TOC浓度变化,对反应前后的S-NZVI进行表征,分析S-NZVI和PS对NB的联合降解机制.以纳米硅胶溶液为胶结剂,以PS为活性成分,制备缓释PS溶胶,注入砂柱中扩散形成凝胶,与S-NZVI构成S-NZVI/PS组合反应带,研究其对模拟硝基苯污染地下水的原位修复效果.结果表明,S-NZVI能够高效去除NB并生成大量苯胺（AN）,S-NZVI被PS氧化产生的Fe²⁺与PS组成活化过硫酸盐,对AN具有较好的降解和矿化效果.当NB浓度为100mg/L、S-NZVI和PS的投加量分别为0.5,2.5g/L时,NB去除率达91%,AN出水浓度为1.96mg/L,TOC去除率达64.09%.反应后S-NZVI的主要铁氧化产物为Fe₃O₄和FeO（OH）.反应带实验结果表明,S-NZVI/PS组合反应带可有效去除地下水的NB并高效消减NB还原产生的AN,当进水中NB浓度为100mg/L,流量为0.4mL/min,注入S-NZVI含量为1200mg/L的浆液200mL,二氧化硅含量为30%、PS含量为12.5%的PS凝胶4.8g时,S-NZVI/PS组合反应带7d内对AN的去除率最高达97.6%,NB当量累计去除率为83.7%.