水泥窑焚烧干化污泥烟气污染物排放控制及净化工艺优化

本文通过梳理水泥窑焚烧干化污泥烟气污染物排放的控制方法,优化末端烟气净化处理工艺,对烟气污染物进行进一步控制处理。研究表明,水泥窑协同处置污泥烟气控制的前端控制主要包括:废物种类控制、废物中有害元素的投料控制、投料点的选择等;末端控制主要包括:活性炭吸附、湿式碱法、SCR、LPC等烟气污染物净化控制工艺。通过末端控制的几种工艺的单独净化和组合净化结果比较,"活性炭+LPC"工艺在脱硫脱硝方面效果最佳,对高温管式炉烟气SO2的处理率为95.1%,对NOx的处理率为83.9%。     

转轮除湿系统除湿效率及空气净化效率实验研究

搭建了转轮除湿系统实验台,对其除湿性能及去除污染物的性能进行了测试。研究了再生温度、处理空气和再生空气风量、处理空气含湿量对转轮系统的除湿量和除湿效率的影响,同时也研究了再生温度、处理空气和再生空气风量、处理空气含湿量、污染物浓度对污染物净化效率的影响。实验结果显示:转轮除湿系统在除湿和去除污染物方面均具有良好的性能;除湿量、除湿效率及对污染物的净化效率均会随着再生温度的升高而增大;处理空气含湿量越高,除湿效率越低;处理空气风量越大,除湿量、除湿效率及对污染物的净化效率越低;再生空气风量越大,除湿量、除湿效率及对污染物的净化效率越高;当处理空气的相对湿度低于70%时,处理空气相对湿度对污染物的净化效率影响较小,当相对湿度高于80%时,随着相对湿度的增加,污染物的净化效率急剧下降。     

纳米TiO2-ACF光催化净化室内空气污染物试验

本文提出了纳米TiO2-ACF复合光催化净化室内空气技术,分析了不同条件下复合光催化净化网的净化效率,对ACF吸附网、纳米TiO2光催化净化网和纳米TiO2-ACF复合光催化净化网净化甲醛的净化性能进行了对比分析.复合光催化净化网在高风速且污染物质量浓度较低时净化效率高于其他两种净化网的净化效率近15%.该净化网对无机和有机污染物具有较强的吸附氧化能力、较小的空气阻力、无中间副产物生成,实现了ACF的原位再生,延长了净化网的使用周期.     

美国开发出两项高效环保新技术

美国开发出的污染物玻璃化技术及净化被油类污染过的土壤与水源技术已投入实际应用。 污染物玻璃化技术是采用电熔方法处理被污染的土壤与废弃物,分解有机污染物与放射性污染物,使之玻璃化,以永久方式固定废弃污染物。该方法具有净化效果非常好,成本低,能永久、持续地保持净化后的状态等优点。它适用于有污染物质的净化处理。此外,它还可用于净化被污染的土壤等。     

污水处理厂气态污染物的生物净化技术

介绍生物净化气态污染物的原理及两种典型方法,从解决污水处理厂气态污染物的角度阐述了生物净化的可行性,表明生物法净化废气具有费用低、效率高、二次污染少等特点以及广阔的应用前景。     

工业污水处理厂除臭系统设计

根据大型污水处理厂对恶臭污染物的控制要求,针对不同水处理构筑物设计合理的恶臭气体收集系统、输送系统和净化系统;臭气净化工艺选用稳定性强、能耗低的生物滤池净化工艺,将恶臭污染物净化处理满足相关标准后高空排放。     

500℃高温除尘器的研制及工业性实验

为解决高温气体不降温情况下进行净化,研制了耐温500℃的过滤式高温除尘器,技术关键是研制陶瓷纤维滤管和除尘单元切换用的高温阀,并可回收净化后的高温气体热量。     

复合空调室内气态污染物对流输运模拟

利用CFD数值模拟方法分析了复合窗式空调系统对建筑室内气态污染物输运过程的影响.采用雷诺应力模型(RSM)描述了室内空气和污染物对流输运过程,并详细探讨了复合窗式空调系统的送风速度、新风比、净化效率和室内热源强度等对室内气态污染物对流输运过程的影响.计算结果表明,提高送风速度、新风比以及净化效率都能有效降低室内气态污染物平均浓度.值得注意的是,当送风速度超过0.75 m/s后,室内气态污染物浓度水平维持恒定;空调系统即使按全新风模式运行,也不能彻底排除室内污染物.     

北方吸污绿化树种选择

通过人工熏气试验，研究测定了北方部分绿化树种对主要大气污染物－二氧化硫、氯气和氟化氢的吸收净化能力。结果表明：绿化树种对大气污染物具有一定的吸收净化能力，并依污染气体和树种的不同具有明显差异。     

高铁酸钾氧化性在水净化中的应用

论述了高铁酸钾本身具有的强氧化性在水处理中的应用前景及反应原理。研究表明，高铁酸钾能够有效地净化水中微生物、无机以及有机污染物，且污染物的净化效果与高铁酸钾投加当量、溶液pH、反应时间等有关。     

高温煤气净化研究

介绍了在流化床和固定床反应器中对同温煤气中的硫化物、NH3、HCl、焦油组分和碱金属化合物等脱除的全面研究。通过对含量较少的污染物有要硫、NH3、HCl、焦油组分和碱金属化合物等分别进行单独和同时脱 除的研究，提出了同时脱除高温煤气中这些污染物的设想。     

KDF55/椰壳活性炭/石英砂/沸石联用净化饮用水

考察了KDF55、石英砂、沸石、椰壳活性炭联用对饮用水的净化效果.结果表明,系统对浊度的去除主要发生在椰壳活性炭滤层;对铜、铬、铅等重金属离子的去除主要由KDF55滤层完成,去除率均可达80%以上;系统还可明显降低饮用水的硬度和CODMn.该系统在有效去除污染物的同时,又可向水中释放微量对人体有益的锌离子,对家用净水机的开发具有重要的参考价值.     

浐河水质污染特征及水质改善措施分析

针对浐河水体遭受污染问题,通过对浐河水质特征断面的10项指标进行连续监测,分析了浐河水中污染物的组成和水质特征,对污染物的携入方式进行了调查,分析评价了浐河水体污染的原因,并提出了控制浐河水质污染的对策。结果表明,浐河水体中的物理指标水温、p H、重金属指标相对正常;重金属指标中只有少量的Fe、Zn、Cr元素;污染物主要为N、P等营养物质,水体的富营养化程度较为严重;河流水体浊度总体较高且与地表径流存在较高的相关性;污染的主要原因是浐河周边的水厂、污水处理厂所排出污水的点源污染;污染改善措施采用人工湿地、管网改建等适合不同断面特征的控制方式。     

Transport and sources of metal contaminants over the course of tidal cycle in the turbidity maximum zone of the Hudson River estuary

Transport and source of metal contaminants (Ag, Cd, Cu, Pb and Zn) in the turbidity maximum zone of the Hudson River estuary were studied over the course of a tidal cycle in November 1994 and August 1995. This study showed that the metal/Fe ratios in suspended particles varied more widely than those in the local sediments, implying that sources of metal contaminants to the water column are not only from local sediment resuspension but also from lateral advection. Although the metal/Fe ratios oscillate with time at the anchor stations, a general increasing trend with salinity was found over the course of a tidal cycle, suggesting that the lower estuary could be a source of metal contaminants to the upper estuary regions. These results support that sediment resuspension and lateral advection are important factors responsible for transporting the lower estuary contaminants up river and redistributing metal contaminants in the estuary.     

The influence of heat treatment on the metallic and polycyclic aromatic hydrocarbon content of sewage sludge: A pilot plant study

Heat treatment of sewage sludge facilitates its dewatering. The liquors produced inevitably contain a portion of the heavy metal and polycyclic aromatic hydrocarbon contaminants present in the sludges. Using a pilot plant, the influence of time and temperature of treatment on the concentrations of these pollutants in the liquors and treated sludges from three types of untreated sludge have been determined. Statistical analysis of the data has been used to identify significant effects of the treatment process. It is concluded that heat treatment would not produce significant increases in the concentrations of these contaminants in sewage effluents.     

Phosphate sources and their suitability for remediation of contaminated soils

Phosphate minerals and specifically apatite show promise for environmental cleanup because they can form stable compounds with a wide range of cationic contaminants. However, phosphate minerals naturally accumulate some heavy metals that may cause additional contamination of the environment if used improperly. Nine commercially available phosphate materials were evaluated for remediation of contaminated soil based on solubility, concentration of metal/metalloid impurities, and leachability of impurity metal/metalloids. The phosphate materials consisted of three groups: processed (i.e., fertilizers), mined (rock phosphates from different formations), and biogenic (ground fish bone). Processed and mined rock phosphates contained relatively high total concentrations of As, Co, Cr, and Cu but did not exceed the RCRA toxicity characteristic leaching procedure (TCLP) limits. Biogenic apatite contained much lower metal concentrations than processed and mined rock phosphate and was appreciably more soluble. By combining biogenic and mined phosphate it is possible to obtain a wide range of phosphate release rates, permitting rapid immobilization of contaminants while providing a slow release of phosphate for continued long-term treatment.     

氨氮污水在河流渗滤系统中的环境效应研究

河流渗滤系统作为天然的过滤器及生物地球化学反应器,可以除去河水中多种污染物。本文采用自行设计的室内土柱实验装置来模拟渭河渗滤系统,模拟研究了含有氨氮污染的河水在渗滤系统中的环境行为及净化机制,其环境行为包括阳离子交替吸附作用、硝化作用和反硝化作用。得出河流渗滤系统对氨氮污水有一定的净化作用,其净化率为86%。     

Use of spider webs as indicators of air quality assessment of Lahore City

High level of heavy metal contaminants in air is known to cause serious health problems if remained unchecked for a long period of time. Anthropogenic activities such as vehicular emissions and number of industries are responsible for increasing the level of heavy metals. The aim of the present study was to biologically monitor the level of heavy metal contamination by spider webs. These sites were selected based on variable traffic volume and number of industries. Atomic absorption spectrometry (AAS) was used for the analysis of metal pollution content. The study determined that the level of heavy metals at the selected sampling sites were several folds higher than that at the control site and in previously reported literature. Pb was determined to be the most abundant heavy metal, while Thokar Niaz Baig was reported as the most contaminated site. These elevated levels of metal contaminants are associated with heavy traffic flow, number of industries and constructional activities in the respective areas.     

Adsorption of Pb and Cd by amine-modified zeolite

Natural zeolites, known for their excellent sorption properties towards metal cations, are widely used for the purification of wastewaters. The selectivity of clinoptilolite, a common zeolite mineral, for Pb is known to be particularly high, whereas its selectivity for Cd is often lower. Extraordinarily high sorption capacities for soft metal cations were observed in the case of thiol-functionalized silica gels and clays. In order to enhance the zeolites' sorption capacity for Cd, we treated natural heteroionic and Na-clinoptilolite in aqueous suspensions with cysteamine and propylamine solutions and investigated the sorption of Cd and Pb to amine-modified zeolite by a series of batch experiments. Stability constants for amine sorption on all zeolite samples at room temperature and 50 degrees C were obtained. Partial dimerization of cysteamine explains the enhanced sorption of this compound. In contrast, amine treatment did not enhance the adsorption capacity or selectivity of the clinoptilolite towards Cd and Pb. Instead, the amounts of adsorbed heavy metals decreased stoichometrically with increasing sorption of cysteamine and propylamine. This reduction can be explained by the blockage of channels by amine molecules and revealed that the modification of zeolites with mercaptoamines does not enhance the sorption capacity of zeolite for Cd and Pb.