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171.
污泥含炭吸附剂对挥发性有机废气吸附实验研究   总被引:1,自引:0,他引:1  
研究了污泥含炭吸附剂对挥发性有机污染物的吸附特性。结果表明,污泥含炭吸附剂对苯系物的吸附为典型的物理吸附,其吸附甲苯等温线的类型系优惠型吸附等温线,表明具有良好的吸附能力;在吸附反应温度为20℃,气体流量为500 mL/m in(停留时间为0.424 s),甲苯浓度为2 700 mg/m3时,甲苯的饱和吸附容量为150.0 mg/g;同时,研究表明污泥含炭吸附剂对苯系物的饱和吸附容量和吸附强弱次序为二甲苯甲苯苯。结果表明污泥含炭吸附剂适合对中低浓度有机废气的吸附净化。  相似文献   
172.
改性粉煤灰协同PSFA处理高度乳化油废水   总被引:4,自引:2,他引:2  
通过正交实验对改性粉煤灰协同粉煤灰基混凝剂PSFA处理高度乳化油废水的工艺条件进行了优化。实验结果表明:当处理500 mL废水,投加改性粉煤灰25 g,粉煤灰基混凝剂6~8 g,PAM6~9 mL,pH为7.0,搅拌10~15 min的优化条件下,高度乳化油废水中COD、石油类物质的去除率可分别可达85.4%及50.3%。该方法与传统CaCl2+PFS+PAM组合相比,具有处理效果好,沉降速度快,运行费用低等优点。  相似文献   
173.
新型活性炭固定化产品的制备及其处理焦化废水的特性   总被引:1,自引:0,他引:1  
为解决优势菌种工程应用,研究不同固定化方法、载体和结构的固定化产品对焦化废水的降解特性。用活性炭粉末吸附菌种后,与聚乙烯醇和海藻酸钠混合制备了新型固定化球;用聚乙烯醇和海藻酸钠包埋吸附菌种的活性炭纤维毡,与立体弹性塑料填料连用,制备出3种不同形状的活性炭纤维膜片固定化产品复合填料。将游离菌和制备的4种活性炭固定化产品投入A/A/O工艺系统平行实验,考察处理焦化废水的效果。结果表明,活性炭纤维膜片固定化产品复合填料对焦化废水的降解能力优于其他固定化产品:缺氧池出水硝酸盐氮和亚硝酸盐氮浓度分别稳定在1.96 mg/L和0.49 mg/L,未产生氮的累积现象,COD去除率可达到60.92%。好氧池COD和氨氮降解效率分别为78.83%和85.52%,苯酚、氰化物降解效率均为97%以上。  相似文献   
174.
壳聚糖三元接枝共聚物的合成及其阻垢性能   总被引:1,自引:1,他引:0  
以壳聚糖(CTS)、衣康酸(IA)和马来酸酐(MA)为原料,以醋酸为溶剂、(NH_4)_2S_2O_8为引发剂,合成了CTS-IA-MA三元接枝共聚物。聚合反应的最佳条件为:反应温度90℃,n(CTS):n(IA):n(MA)=1:1.5:1.0,引发剂质量分数0.35%,反应时间5 h。通过傅立叶变换红外光谱(FTIR)表征,所得产物为CTS-IA-MA接枝共聚物。三元接枝共聚物质量浓度为50 mg/L、水样pH为中性或弱酸性时三元接枝共聚物对CaCO_3的阻垢效果较好。  相似文献   
175.
采用含固定化微生物的曝气生物滤池(G-BAF)处理炼油厂高浓度废水。当G-BAF池进水COD为298~11 278 mg/L时,出水COD为33.0~94.3 mg/L,COD平均去除率为97%;当G-BAF池进水ρ(NH_3-N)为12.1~188.0 mg/L时,出水ρ(NH_3-N)为0.9~49.4 mg/L,NH_3-N平均去除率为83%。经G-BAF处理后出水水质完全达到GB8978—1996《污水综合排放标准》第二类污染物的二级排放标准。  相似文献   
176.
Carbonaceous aerosols were studied at three background sites in south and southwest China. Hok Tsui in Hong Kong had the highest concentrations of carbonaceous aerosols (OC = 8.7 ± 4.5 μg/m3, EC = 2.5 ± 1.9 μg/m3) among the three sites, and Jianfeng Mountains in Hainan Island (OC = 5.8 ± 2.6 μg/m3, EC = 0.8 ± 0.4 μg/m3) and Tengchong mountain over the east edge of the Tibetan Plateau (OC = 4.8 ± 4.0 μg/m3, EC = 0.5 ± 0.4 μg/m3) showed similar concentration levels. Distinct seasonal patterns with higher concentrations during the winter, and lower concentrations during the summertime were observed, which may be caused by the changes of the regional emissions, and monsoon effects. The industrial and vehicular emissions in East, Southeast and South China, and the regional open biomass burning in the Indo-Myanmar region of Asia were probably the two major potential sources for carbonaceous matters in this region.  相似文献   
177.
In urban cities in Southern China, the tissue S/N ratios of epilithic mosses (Haplocladium microphyllum), varied widely from 0.11 to 0.19, are strongly related to some atmospheric chemical parameters (e.g. rainwater SO42−/NH4+ ratios, each people SO2 emission). If tissue S/N ratios in the healthy moss species tend to maintain a constant ratio of 0.15 in unpolluted area, our study cities can be divided into two classes: class I (S/N > 0.15, S excess) and class II (S/N < 0.15, N excess), possibly indicative of stronger industrial activity and higher density of population, respectively. Mosses in all these cities obtained S and N from rainwater at a similar ratio. Sulphur and N isotope ratios in mosses are found significantly linearly correlated with local coal δ34S and NH4+-N wet deposition, respectively, indicating that local coal and animal NH3 are the major atmospheric S and N sources.  相似文献   
178.

Purpose

The environmental issues caused by the municipal solid waste disposal are becoming a worldwide concern.

Methods

We studied the situations both domestically and abroad by the strategic environmental assessment (SEA) approach and also conducted comprehensive evaluations of garbage disposal in Changchun City.

Results

On the basis of this study, we found that SEA is of great importance in the municipal solid waste disposal. Moreover, with the rapid socioeconomic development of Changchun City, municipal solid waste production increases on an annual basis, and thus, good waste management planning is of great significance.

Conclusions

Considering the situation of the economic development of Changchun City, garbage disposal was handled mainly in the major sanitary landfills with appropriate use of incineration technology. This plan is environmentally friendly at a relatively high degree and has met the requirements of minimum investment. It also takes into account the requirements of the development of incineration technology. Regarding environmental pollution in terms of groundwater pollution and atmospheric pollution, this plan is a feasible one by meeting various requirements with low environmental impact among the three plans discussed in this study.  相似文献   
179.
植物配置对表层流湿地净化效果的影响研究   总被引:2,自引:0,他引:2  
以郑州市贾鲁河河水为处理对象,研究了不同植物配置表层流湿地的水质净化效果及影响因素。研究表明,单纯挺水植物湿地对TN、TP、NH4+-N和COD的平均去除率分别为28%、58%、49%和26%;采用沉水植物+浮叶植物+挺水植物组合的湿地对TN、TP、NH4+-N和COD的平均去除率分别为37%、64%、63%和32%,在对NH4+-N和TN的处理效果上表现出明显的优势,DO含量变化是导致处理效果差异的主要原因。研究结果表明,在湿地植物配置上,可从氮循环的角度,通过合理搭配湿地植物,强化硝化反硝化作用,以提高对氮素的去除效果。  相似文献   
180.
Based on environmental monitoring data in 93 major cities and meteorological records at 398 weather stations in China from 1981 to 2007, total suspended particle (TSP) concentration, the intensity of dustfall, and sand and dust storm frequency (Fd) were analysed. During the past 27 years, the annual average TSP concentration (CTSP) in 93 cities was 402 μg m?3. Annual average CTSP decreased from the north to the south and from inland to the coast areas with a peak value of 628.8 μg m?3 in Lanzhou. In the 1980s, 1990s and 2000s, annual average CTSP was 628.7, 319.2, and 250.1 μg m?3, respectively. Annual average intensity of dustfall (Id) was 240.5 t km?2 a?1, decreased from northern to southern China and from inland to the coast areas with the maximum value of 717.2 t km?2 a?1 in Baotou. In the 1980s, 1990s and 2000s, annual average Id was 334.8, 220.9, 146 t km?2 a?1 respectively. Annual average Id in the Loess Plateau region was commonly higher than 200 t km?2 a?1. The annual average Fd decreased from arid regions in northwestern China to humid areas in southeastern China with two sand and sand storm centers existing in Xinjiang Taklamakan Desert and western Inner Mongolia. The annual average Fd in the 1980s, 1990s, 2000s was 16, 8, 6 days respectively, decreased steadily from 18 days in 1981–5 days in 2007. Annual average Id had a positive linear relation to annual average CTSP (R2 = 0.96). Annual average Fd had a positive relation with annual average CTSP (R2 = 0.97) as well as annual average Id (R2 = 0.94). TSP was the chief pollutant influencing Air Pollution Index (API) in northern China in spring and winter seasons. Sand and dust storm might be a major factor affecting the temporal variability and spatial distribution of TSP and dustfall in China.  相似文献   
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