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271.
生态农业园区废弃物资源化处理利用研究   总被引:2,自引:0,他引:2  
本文介绍了蟹岛生态园区农业废气物及生活污水的资源化处理工艺方案 ,通过对沼气池和生活污水厌氧 -好氧 -生态塘处理系统进行综合设计 ,实现了节能环保和废弃物无害化综合处理利用。形成了种植业、养殖业、肥料加工、能源利用和休闲度假有机结合的生态农业经济 ,为实现农村经济可持续发展提供了一种新模式  相似文献   
272.
本文对Fenton试剂和生物法联合处理有机废水的工艺流程、适用废水种类、废水处理机理和衡量指标进行了综述,并对Fenton试剂和生物法相结合处理有机废水研究进行了展望。  相似文献   
273.
生物法处理NOx废气的研究进展   总被引:2,自引:0,他引:2  
氮氧化物 (NOx)是主要的大气污染物之一 ,是治理大气污染的一大难题。对当前国内外生物处理NOx 的研究现状进行了系统的论述 ,介绍了生物过滤法处理氮氧化物的基本原理 ,分析了生物过滤法处理氮氧化物存在的问题 ,并预测该技术的未来发展趋势  相似文献   
274.
使用浸渍法制备的CuO Al2 O3催化剂对吸附苯酚饱和的活性炭进行非均相催化湿式氧化再生研究 ,考察了反应温度、反应时间、催化剂投加量、反应氧分压、投炭量、蒸馏水量对非均相催化湿式氧化再生活性炭的影响结果 ,同时在该实验中得到非均相CuO Al2 O3催化湿式氧化再生活性炭的最佳条件。对催化剂进行了X衍射分析 ,并通过对催化剂的稳定性进行实验 ,得出该催化剂在进行催化湿式氧化再生活性炭的过程中具有较好的稳定性  相似文献   
275.
农业蔬菜废物处理方法研究进展和探讨   总被引:6,自引:0,他引:6  
目前我国农业蔬菜废物污染问题正日益加重 ,蔬菜废物和其他固体废物相比具有高含水率、高营养成分和基本无毒害的特性 ,适宜于单独收集处理。本文介绍了国内外蔬菜废物处理方法的研究进展 ,包括好氧堆肥法、厌氧消化法、好氧 -厌氧联合处理法 ,并对这些方法的适用条件进行了论述。同时 ,探讨了接种微生物自然堆沤法的初步研究结果  相似文献   
276.
碱洗是硅钢生产的重要环节。碱洗液随使用时间的延长 ,其中会累积大量杂质 ,造成碱液清洗效率下降而失效。本文使用磁选与浮选联合法去除碱液中的杂质 ,达到了提高碱洗效率并实现碱液的循环再用  相似文献   
277.
Chang CY  Hsieh YH  Lin YM  Hu PY  Liu CC  Wang KH 《Chemosphere》2001,44(5):1153-1158
The object of this research was to study the formation of disinfection by-products by using chlorine dioxide (ClO2) as a disinfectant reacting with different properties of organic substance in natural aquatic environment. The adsorbent resin (XAD-4, XAD-7) was used to divide the organic matters in raw water into three groups. The influence of the function groups on structure, reaction tendency, and formation of disinfection by-products generated by the reaction of these organic substances with chlorine dioxide was explored. The experimental results show that the three different organic groups formed using adsorbent resin were hydrophobic substance, hydrophilic acid, and non-acid hydrophilics in proportions of 43%, 41%, and 16%, respectively. Within the raw water in our study, the hydrophilic substance had a higher distribution proportion than that described in general articles and journals, which indicates that this water was contaminated with pollution from human beings. The exploration of the reactivity of the three different organic substances with chlorine dioxide shows that the unit consumption of disinfection agent per unit organic matters (represented by ClO2/DOC) is in the following sequence hydrophobic substance > hydrophilic substance > non-acid hydrophilics. It indicated that larger molecular organic precursors had larger consumption of disinfectant. We also discovered that after the reaction of the three different organic substances with chlorine dioxide, the largest amount of disinfection by-products were generated by the non-acid hydrophilics.  相似文献   
278.
Environmental Science and Pollution Research - Composite adsorbents usually outperform single component adsorbents as they could combine the properties and advantages of each component. In this...  相似文献   
279.
Wu Z  Zhou M  Wang D 《Chemosphere》2002,48(10):1089-1096
A novel electrocatalysis method for phenol degradation was described using a β-PbO2 anode modified with fluorine resin and a Ni–Cr–Ti alloy cathode. In case of air sparging at the cathodic zone, the techniques of anodic–cathodic electrocatalysis (ACEC) and ferrous ion catalyzed anodic–cathodic electrocatalysis (FACEC) in the presence of iron(II) were developed. Both of ACEC and FACEC were more effective than anodic electrocatalysis (AEC). The percentage of phenol eliminated by FACEC could increase by nearly 30% compared with that of AEC, and the current efficiency could reach to 70%. Important operating factors such as ferrous ion concentration, air-sparging rate and applied current were investigated and it was found that such beneficial effects could be achieved at a suitable current and ratio of the concentration of ferrous ion to the air sparged. The mechanism of phenol degradation is proposed to be the generation of hydroxyl radicals concerned with the two electrodes. Results also indicated that the process provided an efficient way to regenerate ferrous ion compared with the conventional Fenton's system.  相似文献   
280.
Wang X  Sun C  Wang Y  Wang L 《Chemosphere》2002,46(2):153-161
The comparative toxicities of selected phenols to higher plants Cucumis sativus were measured and the negative logarithm molar concentration of the root elongation median inhibition (IRC50) were derived. Quantitative structure-activity relationships (QSARs) were developed to explore the toxicity influencing factors and for predictive purpose. The toxicity data, fell into two classes: polar narcosis and bio-reactive. For polar narcotic phenols, a highly significant two-parameter QSAR based on 1-octanol/water partition coefficient (logKow) and energy of the lowest unoccupied orbital (E(lumo)) was derived (IRC50 = 0.77 log Kow - 0.39E(lumo) + 2.36 n = 22 r2 = 0.89). The five bio-reactive chemicals proved to show elevated toxicity due to their typical substructure involved diverse reactive mechanisms. In an effort to model all chemicals, a robust multiple-variable QSAR combining logKow, E(lumo) and Qmax, the most negative net atomic charge, was developed (IRC50 = 0.65 logKow - 0.72E(lumo) + 0.23Qmax + 2.81 n = 27 r2 = 0.94), indicating that hydrophobicity, electrophilicity and hydrogen bond interaction contribute mainly to the phytotoxicity. The toxicological data was compared with Tetrahymena pyriformis 2-d population growth inhibition toxicity (IGC50) and excellent interspecies correlations were observed both for the polar narcotics and for five reactive chemicals (for polar narcotics: IRC50 = 0.95IGC50 + 1.07 n = 16 r2 = 0.89; for bio-reactive chemicals: IRC50 = 0.98IGC50 + 2.19 n = 5 r2 = 0.97; and for all: IRC50 = 0.93IGC50 + 1.63 n = 21 r2 = 0.87). This suggested that T pyriformis toxicity could serve as a surrogate of C. sativus toxicity for phenols and interspecies correlation also could be established for reactive chemicals.  相似文献   
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