壳聚糖絮凝机理及絮凝性能的影响因素分析

壳聚糖是一种天然高分子聚合物,被广泛地作为絮凝剂用于水处理过程。探讨了壳聚糖的三种絮凝机理。在水处理中,其絮凝性能的发挥受到pH值、壳聚糖的投加量、壳聚糖的分子量以及壳聚糖的脱乙酰度等因素的影响。     

饮用水中有机物组成及控制技术

介绍了饮用水中有机物的组成及其去除评价指标,并指出了各类有机污染物对饮用水水质的影响。重点探讨了水中各类有机污染物的去除方法：强化混凝、颗粒活性碳、膜过滤、光催化氧化、臭氧一生物活性炭及生物预处理技术等。最后总结了各种处理方法的优缺点,为选择合适的去除有机污染物工艺提供参考。     

Composition regulates dissolved organic matter adsorption onto iron(oxy)hydroxides and its competition with phosphate:Implications for organic carbon and phosphorus immobilization in lakes

Dissolved organic matter(DOM)is a heterogeneous pool of compounds and exhibits diverse adsorption characteristics with or without phosphorous(P)competition.The impacts of these factors on the burial and mobilization of organic carbon and P in aquatic ecosystems remain uncertain.In this study,an algae-derived DOM(ADOM)and a commercially available humic acid(HA)with distinct compositions were assessed for their adsorption behaviors onto iron(oxy)hydroxides(FeOx),both in the absence and presence of phosphate.ADOM contained less aromatics but more protein-like and highly unsaturated structures with oxygen compounds(HUSO)than HA.The adsorption capacity of FeOx was significantly greater for ADOM than for HA.Protein-like and HUSO compounds in ADOM and humic-like compounds and macromolecular aromatics in HA were preferentially adsorbed by FeOx.Moreover,ADOM demonstrated a stronger inhibitory effect on phosphate adsorption than HA.This observation suggests that the substantial release of autochthonous ADOM by algae could elevate internal P loading and pose challenges for the restoration of restore eutrophic lakes.The presence of phosphate suppressed the adsorption of protein-like compounds in ADOM onto FeOx,resulting in an increase in the relative abundance of protein-like compounds and a decrease in the relative abundance of humic-like compounds in post-adsorption ADOM.In contrast,phosphate exhibited no discernible impact on the compositional fractionation of HA.Collectively,our results show the source-composition characters of DOM influence the immobilization of both DOM and P in aquatic ecosystems through adsorption processes.The preferential adsorption of proteinaceous compounds within ADOM and aromatics within HA highlights the potential for the attachment with FeOx to diminish the original source-specific signatures of DOM,thereby contributing to the shared DOM characteristics observed across diverse aquatic environments.     

聚合硫酸铁和聚合硫酸铝的配伍和性能研究

将聚合硫酸铁 (PFS)与聚合硫酸铝 (PAS)按一定比例混合 ,即可制得一类具有不同铝铁含量的新型净水剂——聚合硫酸铁铝 (PFAS)混合液 ,分析、检测了几种 PFAS的性质及其净水性能。结果表明 ,PFAS的综合性能优于 PFS和PAS,更能适应原水水质的变化 ,其中尤以铝铁分子摩尔比为 0 .64的 PFAS性能最优。     

絮凝法处理纸浆漂白废水的研究

研究了无机絮凝剂ＰＡＣ，ＰＳＡ，ＰＥＳ，ＭｇＣｌ２，ＣａＯ及其与有机高分子絮凝剂ＣＧＡ复全使用对两种不同工艺漂白废水的混凝处理特性，结果表明，水质１ＣＯＤｃｒ，ＡＯＸ去除率分别为６３．２％，４５．３％，水质２ＣＯＤｃｒ，ＡＯＸ去除率达７３．１￥％，５３．４％。化钙与碳酸钠具有相同的降解ＡＯＸ能力，硫离子在中性ｐＨ条件下可显著提高ＡＯＸ的去除率。     

化学除磷在中水回用工程中的运用和控制条件

以中水回用工程中总磷的去除为研究对象,考察了化学除磷方法中影响除磷效果的几个因素及其控制条件。结果表明,GT值对化学除磷的效果影响很大;在适当的混凝搅拌条件下聚合硫酸铁对总磷具有良好的去除效果,可使剩余总磷降到0.5 mg/L以下,满足中水回用水质标准。     

木薯淀粉废水的絮凝法处理

对木薯淀粉废水的絮凝进行了试验研究，结果表明，某些进口高分子絮凝剂有较好的絮凝效果，CODCr去除率大于60％，最高可达99．3％，总固形物去除率大于45％，最高可达66．8％，絮凝最佳pH值为7．0～8．5，最佳加药量为2～6mg/L，生石灰量为0．25～0．5kg/t,废水，总药剂费小于0．3元／t废水，絮凝下沉物含水率为92％左右，易脱水分离，因此，可用于木薯淀粉废水的前处理。     

藻毒素与健康效应的研究进展

淡水水体的富营养化导致蓝藻水的普遍发生，蓝藻产生的多种毒素，如微囊藻毒素，节球藻毒素等，不仅常常引起动物中毒，而且也会影响人类的健康，该文从毒理学的角度阐述了多种藻毒素的毒性，及其所引起的健康效应和发生的可能机制。     

混凝处理抗生素废水研究

采用混凝法对抗生素废水进行预处理.试验结果表明:混凝沉淀方法去除混合液中的有机物及部分非溶解态的溶媒物质具有较好的效果,CODCr平均去除率达到32.0%,且运行成本合理,具有较高的应用价值.     

A critical review of the influence of effluent irrigation on the fate of pesticides in soil

The impact of effluent irrigation on the transformation and mobility of organic contaminants is poorly understood. The objectives of this review paper are: (i) to discuss the fundamental processes influencing the transformation and transport of pesticides in soil; (ii) to present a critical analysis of the impact of effluent irrigation on the transformation and transport of pesticides in soils; (iii) to suggest research areas that need attention. Effluent irrigation affects the fate of pesticides through its direct effect on the transformation and transport of pesticides that are already present at the irrigation sites, and its indirect effect on soil properties that are important in controlling the transformation and transport of organic contaminants. It has often been noticed that the effluent-derived dissolved organic matter (DOM) facilitates the movement of soil-borne pesticides by forming soluble pesticide complexes, and enhances their biodegradation by providing energy sources for the microorganisms that are involved in pesticide degradation. However, the results of field and laboratory experiments that examined the effect of effluent irrigation on the fate of pesticides are inconsistent; in some cases reduced mobility resulting from enhanced pesticide sorption has been observed, but enhanced pesticide mobility has also been reported. The inconsistency may be related to the inherent spatial variability of soil properties and/or the heterogeneity of effluent quality. For example, effluents vary in the nature and concentration of DOM that play a vital role in the degradation, sorption and transport behaviour of pesticides. Similarly, they vary in the concentrations of solvents and surfactants that have been shown to impact sorption and transport of organic contaminants. Field-based investigations on the impact of effluent irrigation on pesticide fate coupled with an accurate characterisation of the effluent are urgently required to assess the long-term risk associated with effluent irrigation in relation to pesticide transformation and transport.