电子废弃物中贵重金属的回收技术研究

目前电子废弃物数量巨大,对生态环境产生了严重的危害,并且其中的贵重金属成分的潜在价值很高,所以,对电子废弃物中的贵重金属的回收迫在眉睫。总结了电子废弃物处理的传统技术,包括机械处理、火法和湿法冶金技术等。针对以上方法的特点及流程,从技术上和经济上分析其存在的问题,以及对环境造成的影响。另外,详细介绍了生物技术和超临界流体萃取技术在回收贵重金属方面的研究和发展趋势。最后,简要评述了国内电子废弃物处理所面临的问题,并提出了可能的解决方案。     

Improved method for analyzing the degradation of estrogens in water by solid-phase extraction coupled with ultra performance liquid chromatography-ultraviolet detection

We established an improved method for the determination of four estrogens including estriol (E3), 17 -estradiol (E2), 17 -ethynylestrodiol (EE2) and estrone (E1) in water. The method consisted of solid-phase extraction (0.5 L water) and subsequent analysis of analytes by ultra-performance liquid chromatography (UPLC) with an ultraviolet detector (UVD). Base-line separation was achieved for all studied estrogens using a column (50 mm 2.1 mm) packed with 1.7 m particle size stationary phase. Recovery was higher than 88% and detection limits ranged between 12.5–23.7 ng/L for the four estrogens, with the RSD ranging from 7% to 11%. The method was successfully applied to determine E2 and EE2 in simulated natural water, which found that about 70% of E2 was degraded (with a half-life of about 30 hr) within 48 hr and about 55% of EE2 was degraded (with a half-life of about 36 hr). Low levels of E1 were found, however E3 was undetectable during the process.     

Synthesis and adsorption performance of lead ion-imprinted micro-beads with combination of two functional monomers

Synthesis and high adsorption and selectivity performance of lead ion-imprinted micro-beads with combination of two functional monomers.     

分离高浓度污泥产酸发酵液的自生动态膜形成机制

采用自生生物动态膜分离高浓度污泥发酵液,研究了动态膜的形成过程及其对污泥发酵液的分离效果.结果表明,自生动态膜的形成过程受污泥浓度的影响较小,污泥浓度仅影响初始膜通量,不影响稳定时的膜通量.膜通量随着滤布孔径和搅拌速度的增大而增大.动态膜的形成过程符合死端过滤模型,分别由以下4个过程构成:先通过与膜基材孔径相似的污泥颗粒堵塞膜基材孔,其后在膜基材上形成单层污泥,进而在膜基材上形成多层污泥,最后,大颗粒污泥继续沉积到污泥层上.动态膜形成后,对污泥颗粒和溶解性COD(SCOD)的截留率分别为98%和28%,对挥发性脂肪酸(volatile fatty acids,VFAs)的渗透率在82%以上,胞外聚合物(extracellular polymeric substances,EPS)中的蛋白质是动态膜的主要成分.     

BiOCl-(NH4)3PW12O40复合光催化剂制备及其光催化降解污染物机制

光生电子和空穴的分离效率是影响光催化性能的重要因素.氯氧铋是典型的层状纳米光催化剂,却因光生电子和空穴的快速复合所表现出的低量子效率而受到使用限制.本文通过两步的水热法合成了BiOCl-(NH_4)_3PW_(12)O_(40)复合光催化剂.以甲基橙(MO)为模拟污染物进行光催化活性测试.结果表明,在氙灯模拟的太阳光照射下,Bi与W的原子比为1∶1时,其催化效果最佳.通过自由基猝灭实验对催化剂光降解MO的催化机制进行了研究,发现BiOCl是由空穴,羟基自由基和超氧自由基共同作用来对MO进行降解;而复合催化剂则主要以羟基自由基和超氧自由基为活性物种来降解MO.通过对反应前后的催化剂进行XPS分析,证明了磷钨酸铵可以接收BiOCl产生的光生电子.通过光电流测试,表明复合光催化剂的光生电子的转移和分离效率有了较大的提高,从而提高了光催化活性.     

新OG系统旋流脱水器气液分离特性数值研究

根据旋流脱水器的内部流动特性,基于欧拉-拉格朗日方法,对旋流脱水器内部气液两相流动进行了数值计算和分析,研究了液滴直径、进口质量含气率和湍流扩散效应对流场分布、脱水效率、出口质量含气率和出口液滴粒度分布的影响.结果表明：当质量流量一定时,旋流脱水器进出口压降随着进口质量含气率的增加而显著提高.对于单一直径的液滴,在不考虑湍流扩散效应的情况下,脱水效率随进口质量含气率的增加而增加.当考虑湍流扩散效应时,对于直径较小的液滴（0.1~1μm）,这种规律刚好是相反的,连续相速度的增加提升了湍流扩散速度,使湍流运动更加紊乱,但脱水效率高于不考虑湍流扩散效应时的计算结果.在混合粒径条件下,随着进口质量含气率的增加,脱水效率和出口质量含气率增加,计算表明湍流扩散效应有利于混合直径液滴的分离.随着进口质量含气率的增加,液滴质量分数的峰值逐渐向小粒径方向移动,粒径分布范围逐渐减小.     

Bioinspired and biomimetic membranes for water purification and chemical separation: A review

•The history of biological and artificial water channels is reviewed. •A comprehensive channel characterization platform is introduced. •Rationale designs and fabrications of biomimetic membranes are summarized. •The advantages, limitations, and challenges of biomimetic membranes are discussed. •The prospect and scalable solutions of biomimetic membranes are discussed. Bioinspired and biomimetic membranes that contain biological transport channels or attain their structural designs from biological systems have been through a remarkable development over the last two decades. They take advantage of the exceptional transport properties of those channels, thus possess both high permeability and selectivity, and have emerged as a promising solution to existing membranes. Since the discovery of biological water channel proteins aquaporins (AQPs), extensive efforts have been made to utilize them to make separation membranes–AQP-based membranes, which have been commercialized. The exploration of AQPs’ unique structures and transport properties has resulted in the evolution of biomimetic separation materials from protein-based to artificial channel-based membranes. However, large-scale, defect-free biomimetic membranes are not available yet. This paper reviews the state-of-the-art biomimetic membranes and summarizes the latest research progress, platform, and methodology. Then it critically discusses the potential routes of this emerging area toward scalable applications. We conclude that an appropriate combination of bioinspired concepts and molecular engineering with mature polymer industry may lead to scalable polymeric membranes with intrinsic selective channels, which will gain the merit of both desired selectivity and scalability.     

污水处理厂恶臭烦恼模拟评价及验证

对某污水处理厂有组织及无组织源进行采样调查,基于CALPUFF模型建立恶臭评价因子,对恶臭扰民进行判定,并通过厂界样品检测、现场嗅探监测、居民问卷调查3种方式对模型模拟结果进行验证.结果表明,该污水处理厂在各个方向上的恶臭防护距离为200~1450m,周边8个居民区可引起恶臭烦恼;模型模拟得到的臭气浓度及居民烦恼与验证结果一致性较好.     

高浓度硫化染色废水处理新工艺研究

采用混凝沉淀－铁屑过滤,碱析组合工艺处理高浓度硫化染色废水。生产性试验结果表明,此工艺对硫化物、ＣＯＤ、ＢＯＤ５和色度的去除率分别达９７．０％、８４．７％、８５．７％和９８．９％,处理后出水的各项污染指标均符合国家排放标准,具有系统运行稳定,操作管理简便,工程投资少,处理低等优点。     

造纸废水的治理研究

介绍了造纸废水处理技术的研究现状,讨论了各自的作用机理及其在造纸废水处理中的应用.为工程设计和生产工艺提出了一些有益的建议.在此基础上对造纸废水处理的发展趋势做了分析和展望.