2,4-dichlorophenoxyacetic acid (2,4-D) micropollutant herbicide removing from water using granular and powdered activated carbons: a comparison applied for water treatment and health safety

Abstract

Activated carbons are well-known porous materials as an effective adsorbent used for the removal of emerging contaminants, such as herbicides, which are increasingly present in water bodies. Most water treatment plants, specially in Brazil, are unable to completely remove such contaminants by the conventional process and advanced treatment using activated carbons is required. The aim of this paper was to verify the influence of the activated carbons granulometry and specific surface area on the 2,4-dichlorophenoxyacetic acid (2,4-D) herbicide removal efficiency using distilled-deionized water and filtered water collected from a conventional Water Treatment Plant. Commercial activated carbons samples used in this work were obtained from two different manufacturers. Activated carbons were analyzed by the specific surface area, pore size and volume distribution, nuclear magnetic resonance, infrared and x-ray spectroscopy, moisture, volatile matter and ash contents. Batch adsorption isotherms experiments were used and performed by Langmuir and Freundlich models. Granular and powdered activated carbons removed over 99% of 2,4-D in distilled water and near to 99% using filtered water. The activated carbons evaluated in this work presented high performance and played a key role in water treatment by removing 2,4-D herbicide, ensuring the protection of human health and the ecosystem.     

喷雾干燥法在垃圾焚烧尾气净化中的应用

以枣庄市资源电厂为例,介绍了喷雾干燥法在垃圾焚烧尾气净化中的应用。     

工业型煤复合粘结剂的研制

根据高聚物相似互溶、扩散渗透原理,采用苎麻黑液、造纸黑液、酒糟废水、淀粉黄浆废水等10种高浓度有机废水(液)作为原料,研制成用于工业型煤的复合粘结剂,使高浓度有机废水(液)得到经济、合理的资源利用。这种粘结剂中含有多种天然高分子物质,可交联成三维空间网状结构,使工业型煤具有较高的机械强度和防潮抗水性能,并同时解决了燃煤和高浓度有机废水(液)的环境污染问题。     

连续流间歇曝气工艺的氮磷脱除功能研究

连续流间歇曝气工艺是在对传统活性污泥法的改造中发展起来的一种工艺。本文针对该工艺的氮磷脱除功能进行了小试研究 ,由试验结果可看出 ,连续流间歇曝气工艺简便易行 ,去除有机物及氨氮的效果稳定 ,在碳源满足脱氮除磷要求的条件下 ,可达到良好的氮磷脱除效果     

Simultaneous denitrifying phosphorus accumulation in a sequencing batch reactor

In order to achieve simultaneous nitrogen and phosphorus removal in the biological treatment process, denitrifying phosphorus accumulation (DNPA) and its affecting factors were studied in a sequencing batch reactor (SBR) with synthetic wastewater. The results showed that when acetate was used as the sole carbon resource in the influent, the sludge acclimatized under anaerobic/aerobic operation had good phosphorus removal ability. Denitrifying phosphorus accumulation was observed soon when fed with nitrate instead of aeration following the anaerobic stage, which is a vital premise to DNPA. If DNPA sludge is fed with nitrate prior to the anaerobic stage, the DNPA would weaken or even disappear. At the high concentration of nitrate fed in the anoxic stage, the longer anoxic time needed, the better the DNPA was. Induced DNPA did not disappear even though an aerobic stage followed the anoxic stage, but the shorter the aerobic stage lasted, the higher the proportions of phosphorus removal via DNPA to total removal. Translated from Environmental Science, 2004, 25(6): 92–96 [译自: 环境科学]     

城市污水除磷中的有关问题

分析了溶解氧浓度、污水中可生物降解有机物浓度及NOX浓度、污泥龄、污泥处理方式等对污水生物除磷的影响，在此基础上提出了提高污水除磷效果的工程措施，最后通过工程实例说明城市污水的除磷特点。     

锅炉应用旋风除尘器除尘的影响因素分析

通过对旋风除尘器结构和运行原理的分析,找出锅炉应用旋风除尘器除尘效果不佳的影响因素,提出了锅炉应用旋风除尘器提高除尘效率的措施.     

高浓度有机废气生物处理研究

对生物滴滤器处理低流量、高浓度有机废气进行了研究。考察了高浓度下的有机废气净化。研究表明,正常运行情况下生物滴滤器对高浓度有机废气具有良好的净化效果,不同的污染物在相同的填料高度下具有一定的处理效率,且在一定的填料段内生化去除速率基本稳定,整个填料塔存在最大生化去除速率。     

污染气象与火电厂除尘效率关系探讨

秦岭淮河以南地区具有平原型气象特征，大气污染扩散有其地域性规律。大型火力发电厂在地方大气污染防治中有着举足轻重的地位。探讨平原型污染气象与火电厂除尘效率的关系，寻求大气污染物 总量控制的途径。     

工业废弃物在煤燃烧过程中脱硫行为的研究

提出了采用工业废弃物作为煤燃烧高温脱硫剂和催化促进剂的思路，对催化促进脱硫的机理进行试验研究，在此基础上提出几种不同配方的脱硫添加剂，并进行详细的试验研究，最终在6t/h工业链条上取得50％左右脱硫率的结果。