含氯苯和对邻硝基氯苯农药废水的混凝—氧化预处理

采用混凝沉淀 -芬顿试剂氧化对含氯苯和对邻硝基氯苯农药废水进行预处理 ,探讨了不同条件下农药废水的处理效果。结果表明 ,废水经混凝处理后可去除 46 .2 %的COD ,BOD5/COD值有一定程度的提高 ;废水经芬顿试剂氧化处理后可去除 5 0 .9%的COD ,BOD5/COD值可从 0 .0 4提高到 0 .1     

石灰-聚铁法处理硫酸厂废水的研究

对各种处理硫酸厂废水的方法者了探讨,选择了以百石灰和聚合硫酸铁为药剂去除废水中砷,硫等污染物的方法。该法工艺简单,混凝剂投加量少,运行费用低,处理后的废水可达到排放标准。     

Chemical Treatments of Natural Fiber for Use in Natural Fiber-Reinforced Composites: A Review

Studies on the use of natural fibers as replacement to man-made fiber in fiber-reinforced composites have increased and opened up further industrial possibilities. Natural fibers have the advantages of low density, low cost, and biodegradability. However, the main disadvantages of natural fibers in composites are the poor compatibility between fiber and matrix and the relative high moisture sorption. Therefore, chemical treatments are considered in modifying the fiber surface properties. In this paper, the different chemical modifications on natural fibers for use in natural fiber-reinforced composites are reviewed. Chemical treatments including alkali, silane, acetylation, benzoylation, acrylation, maleated coupling agents, isocyanates, permanganate and others are discussed. The chemical treatment of fiber aimed at improving the adhesion between the fiber surface and the polymer matrix may not only modify the fiber surface but also increase fiber strength. Water absorption of composites is reduced and their mechanical properties are improved.     

混凝一气浮控制三卤甲烷生成势的研究

研究了混凝一气浮工艺对不同分子量区间三卤甲烷生成势（trihalomethanes formation potential,THMFP）的去除效果及絮体形态对THMFP去除效果的影响。结果表明,混凝一气浮工艺以去除大分子量区间THMFP为主,对小分子量区间THMFP的去除效果较差。UV254值与THMFP值的线性相关系数为0．9449,UV254值可以较好地反映THMFP的含量。絮体的分形维数为1．17～1．2时,孔隙率较大,可增加絮体对THMFP的活性吸附空间,且絮体相对密度较小,可增强同向絮凝作用,增加絮体和THMFP的接触概率,有利于气浮对THMFP的去除。     

钢铁企业废水污染物形态分析及混凝深度处理试验研究

利用过滤试验与粒径分布试验分析了钢铁工业达标外排废水的各类污染物特征,结合正交试验对混凝处理效果及混凝工艺中各主要影响因素的影响情况进行研究。结果表明,废水中颗粒物主要以粗分散胶体和悬浮态物质为主,PAC／PAM联用对钢铁废水具有较好的处理效果,可有效降低主要影响废水回用的铁锰类污染物,还去除了大部分的有机物及磷类等污染物,各项出水水质指标均达到《城市污水再生利用工业用水水质》（GB／T19923—2005）所规定的循环冷却水回用水质标准。     

Effects of acute γ-irradiation on the aquatic microbial microcosm in comparison with chemicals

Effects of acute γ-irradiation were investigated in the aquatic microcosm consisting of green algae (Chlorella sp. and Scenedesmus sp.) and a blue–green alga (Tolypothrix sp.) as producers; an oligochaete (Aeolosoma hemprichi), rotifers (Lecane sp. and Philodina sp.) and a ciliate protozoan (Cyclidium glaucoma) as consumers; and more than four species of bacteria as decomposers. At 100 Gy, populations were not affected in any taxa. At 500–5000 Gy, one or three taxa died out and populations of two or three taxa decreased over time, while that of Tolypothrix sp. increased. This Tolypothrix sp. increase was likely an indirect effect due to interspecies interactions. The principal response curve analysis revealed that the main trend of the effects was a dose-dependent population decrease. For a better understanding of radiation risks in aquatic microbial communities, effect doses of γ-rays compared with copper, herbicides and detergents were evaluated using the radiochemoecological conceptual model and the effect index for microcosm.     

The transformation of outdoor ammonium nitrate aerosols in the indoor environment

Recent studies associate particulate air pollution with adverse health effects; however, the exposure to indoor particles of outdoor origin is not well characterized, particularly for individual chemical species. We conducted a field study in an unoccupied, single-story residence in Clovis, California to provide data and analyses to address issues important for assessing exposure. We used real-time particle monitors both outdoors and indoors to quantify nitrate, sulfate, and carbon particulate matter of particle size 2.5 μm or less in diameter (PM-2.5). The results show that measured indoor ammonium nitrate concentrations were significantly lower than would be expected based solely on penetration and deposition losses. The additional reduction can be attributed to the transformation indoors of ammonium nitrate into ammonia and nitric acid gases, which are subsequently lost by deposition and sorption to indoor surfaces. A mass balance model that accounts for the kinetics of ammonium nitrate evaporation was able to reproduce measured indoor ammonium nitrate and nitric acid concentrations, resulting in a fitted value of the deposition velocity for nitric acid of 0.56 cm s⁻¹. The results indicate that indoor exposure to outdoor ammonium nitrate in Central Valley of California are small, and suggest that exposure assessments based on total particle mass measured outdoors may obscure the actual causal relationships for indoor exposure to particles of outdoor origin.     

混凝沉淀-二氧化氯氧化法处理印染废水

介绍了混凝沉淀－ＣｌＯ２氧化法处理印染废水的反应机理,工艺流程,处理效果及经济效益分析。在２个工厂的实际应用表明,该法工艺简单,操作方便,投资少,效果好。     

绿色化工环保技术与环境治理的关系

我国化工产业的不断发展,带动了我国经济的飞速发展,给人们的生活带来了许多便利条件,但是与此同时也对我国的环境造成了严重的破坏,化工生产用到许多化学材料,在生产过程中会产生大量的化学废弃物,对环境的污染造成很严重的影响。我国对化工生产给环境保护造成的影响高度重视,随着绿色化工环保技术的出现,有效解决了化工产业造成的环境污染问题,对我国的环境问题进行了有效的改善,对我国工业的发展具有重要意义。本文针对绿色化工环保技术进行分析,探讨绿色化工环保技术在环境治理中的有效应用。     

强化混凝预处理削减中药废水的毒性

采用混凝法对毒性强,COD、SS浓度高,色度大的中药废水进行预处理。首先,通过对比研究聚合硫酸铁（PFS）、聚合氯化铝（PAC）、硫酸铝（AS）、硫酸亚铁（FeSO4·7H2O）对中药废水急性毒性和对COD、SS的去除效果,确定投加方案为 PFS（500 mg·L-1）;其次研究了pH值、助凝剂聚丙烯酰胺（PAM）和壳聚糖（CTS）对PFS混凝效果的影响,并确定了最佳混凝参数。研究结果表明：当初始pH为7.0时,500 mg·L-1 PFS与8.0 mg·L-1 PAM配合使用对中药废水具有最佳混凝效果,COD、SS去除率分别达到38.6%、98.9%,急性毒性由EC50=8.12%的降低至EC50=41.35%,毒性级别由极强削弱至中等。