纺织行业废水污染控制技术梗概与进展

纺织行业排放的废水成分复杂 ,是最难净化处理的污水之一。本文概述了纺织行业废水污染控制净化技术的现状 ,并作了相应的评价与分析     

膜-生物反应器混合液性质对膜污染影响的研究进展

膜-生物反应器作为一种新型的污水处理和回用技术,近年来在基础研究和实际应用领域都得到广泛关注,但是影响其长期稳定运行的膜污染问题却一直没有得到深入研究和解决.混合液特性是影响膜污染控制的重要因素,从混合液理化性质(组成、功能、结构和环境因素)和生物学性质(微生物群落结构、微生物功能特征)2个方面进行介绍,综述了目前关于混合液性质与膜污染关系的研究现状.目前的研究虽然取得一定进展,但在相关性分析、群落特征与膜污染关系、污染层形成机理等方面仍存在许多不足.     

Lead contamination in tea garden soils and factors affecting its bioavailability

The consumption of heavy metals is detrimental to human health and most countries restrict the concentration of metals such as lead (Pb) in food and beverages. Recent tests have detected high Pb concentrations in certain commercial brands of tea leaves and this finding has raised concerns for both producers and consumers. To investigate what factors may be contributing to the increase in Pb accumulation in the tea leaves we collected tea leaves and soils from tea producing areas and analyzed them for Pb concentration, pH and organic matter content. The result showed the Pb concentration of 47% investigated tea leaves samples was beyond 2 mg kg(-1), the permissible levels given by China. The total Pb concentration in the surface and subsurface soil layers averaged 36.4 and 32.2 mg kg(-1), respectively which fall below of the 60 mg kg(-1) limit provided for organic tea gardens in China. The pH of the tea garden soils was severely acidic with the lowest pH of 3.37. Soils under older tea gardens tended to have a lower pH and a higher Pb bioavailability which was defined as the amount of lead extracted by CaCl2 solution than those under younger tea gardens. We found that the concentration of bioavailable Pb and the percentage of bioavailable Pb (bioavailable Pb relative to total Pb concentration) were positively correlated with soil H+ activity and soil organic matter content, and the organic matter accumulation contribute more effects on Pb bioavailability in these two factors. We conclude that soil acidification and organic matter accumulation could contribute to increasing Pb bioavailability in soil and that these could increase Pb uptake and accumulation in the tea leaves.     

Estrogenic effects of phenolic compounds on glucose-6-phosphate dehydrogenase in MCF-7 cells and uterine glutathione peroxidase in rats

In this study, we tested phenolic compounds such as bisphenol A (BPA), 4-nonylphenol (NP), 4-octylphenol (OP) and 4-propylphenol (PP) by using glucose-6-phosphate dehydrogenase (G6PD) in estrogen sensitive human breast cancer cells (MCF-7 cells) and glutathione peroxidase (GPx) in female immature Sprague-Dawley (SD) rats. This study was designed to investigate whether phenolic compounds have estrogenic effects in these useful screening methods for endocrine disruptors. We chose 6 h as the incubation period for the G6PD assay through a preliminary experiment using 17beta-estradiol (E2). Above the concentration of 1 x 10(-8) M, BPA significantly increased the G6PD activity in a concentration-dependent manner, relative to the control. NP (over the concentration of 1 x 10(-9) M) also enhanced the G6PD activity by about 1.8 times that of the control. OP produced weaker effects on G6PD than NP, and showed a tendency to increase the G6PD activity. PP did not affect the G6PD activity. These results show that BPA and NP have the effect of enhancing G6PD activities in MCF-7 cells. In the in vivo GPx assay, both BPA and E2 significantly increased the uterus wet weights and dramatically enhanced uterine GPx activities in immature female rats in a dose-dependent manner. Treatment with NP (500 mg/kg/day) increased significantly both the uterine GPx activity and the uterus wet weights in immature female rats. OP (500 mg/kg/day) also caused a significant increase in uterine GPx activity, but had no effect on the uterus wet weights. This finding indicates that the change in uterine GPx activities could be a more sensitive parameter than that of uterus wet weights in immature rats. This study implies that phenolic compounds have a weak estrogenic effects.     

农业可持续发展的新模式：资源循环型农业

阐述了资源循环型农业的基本概念及其特征,根据循环经济的相关理论和国内外农业发展的实际情况,指出中国农业应在生态农业的基础上,朝着资源循环型农业的目标发展。     

铜酞菁生产中的三废综合治理及其资源化探讨

通过某铜酞菁化工生产企业三废治理及其资源化工艺改进的实践，总结出了一套行之有效的利用酸化工艺废酸的资源化新方法，不但从中回收了高价值的铜泥；同时利用废酸吸收生产工艺中的高含氨尾气，生产硫酸铵，达到了以废治废的目的，整个治理工艺符合循环经济的理念。通过该回收工艺的改进，使上述三废不再进入污水处理系统，从而解决了传统铜酞菁生产废水的高酸度、高盐分、高含氨、高难处理的矛盾，使铜酞菁三废处理易于实行。     

复合植物床式人工湿地研究

本实验研究针对应用于面源污染控制的人工湿地中水生植物的选择和布置问题进行研究,通过对人工湿地动态运行实验的研究考察,发现床体中COD、TN降解规律,通过人工湿地栽种不同水生植物的各床体的COD去除效果比较实验和不同水生植物复氧性能比较实验,得出复氧性能最好的水生植物为芦苇,然后综合这三个实验,在传统的植物床系统基础上,提出更加有利于提高系统污水处理效率的改进形式:复合植物床式人工湿地。     

用于废水处理的膜曝气生物反应器

膜曝气生物反应器是一种利用透气膜进行曝气的污水生物处理组合新工艺.膜曝气的主要特点在于无泡曝气和特殊结构的生物膜.无泡曝气可提高传氧效率,在高浓度废水或含挥发性有机物废水的处理中具有优势.曝气膜上生长的生物膜具有传质异向性,这一特点使其具有同步除碳脱氮的潜力.介绍了膜曝气生物反应器的工艺特点,总结了国内外对于膜曝气生物反应器在废水处理方面的研究进展,指出当前膜曝气生物反应器应用中存在的问题,并展望了今后的发展前景.     

新型混凝剂应用于中水处理的试验研究

围绕着中水回用过程中面临的若干关键问题，通过系统研究筛选高效混凝剂及优化混凝过程来提高污染物去除率，为中水回用提供经济合理的工艺途径。实验结果表明，与FeCl2相比，HPACS系列具有显著优越的除浊与除有机物性能。除磷性能则较为一致，可以达到90％以上的去除率。PFAC系列与FeCl3相比，除浊性能较差，取决于混凝剂中的有效成分的含量，但是具有较为优越的除有机物性能。HPAA系列具有显著优越的除浊和除有机物性能。HPFA与FeCl3系列相比，则具有较高的除磷效果，HPAA的除磷效果则相对较差。不同系列混凝剂具有不同的除浊、除有机物与除磷性能，需要结合分质供水的要求进行优化应用。     

Simulation of 1-year-old Populus tremuloides response to ozone stress at Ithaca, USA, and Suwon, Republic of Korea

The growth of 1-year-old aspen was simulated using TREGRO, a computer simulation model of individual tree growth, to assess potential effects of ozone (O3). TREGRO was parameterized using information from a field experiment conducted at Ithaca, NY, USA; the model was then applied using environmental information from Suwon, Korea, where O3 exposures of aspen had not been conducted. In the parameterization at Ithaca, the simulated and measured total biomass differed by about 3% and the differences between measured and simulated biomass gain of leaf, shoot, and root were 15.4, 8.3, and 4.4%, respectively. Simulating growth at Suwon required adjustment in growth rates to match measured growth due to the different weather conditions at the two cities. The assimilated carbon was evenly distributed to each tissue (foliage, branch, stem, coarse, fine roots) in Suwon, whereas it was mainly allocated to vigorous stem growth in Ithaca. The vigorous growth under Suwon conditions resulted in less total non-structural carbon and perhaps trees more vulnerable to O3 stress. Although the ambient O3 in Suwon (1.2 ppm.h of sum of the hourly concentrations greater than 0.06 ppm [SUM06]) was lower than that in Ithaca (2.1 ppm.h of SUM06), a reduction of 8% of total assimilated carbon was found compared to simulation without O3. Severe effects on root growth at elevated O3 (1.7 times ambient) were predicted; however, the effects on leaf growth would not be as severe.