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951.
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953.
以东江、西江和北江3种原水为研究对象,采用臭氧预处理-常规处理-臭氧活性炭系列处理,研究原水中有机物的去除及臭氧化副产物的产生和转化。结果表明,东江、西江和北江水中CODMn、UV254、甲醛和溴酸盐沿各处理单元过程变化规律基本一致;CODMn总去除率分别为60%、51%和39%,UV254总去除率分别为74%、96%和97%,最终出水甲醛浓度分别为0.004 mg/L、0 mg/L和0 mg/L,BrO3-分别为3.1 μg/L、8.7 μg/L和35.5 μg/L;CODMn的去除主要在预臭氧和活性炭过滤2个处理单元,预臭氧对UV254总去除率贡献最大,甲醛和溴酸盐浓度在主臭氧处理单元达到其峰值(西江甲醛除外);氨氮和有机物浓度较低、pH值较高的北江原水,出水溴酸盐浓度最高。 相似文献
954.
市政污泥深度脱水药剂优化研究简 总被引:1,自引:0,他引:1
污泥含水率高影响污泥后续处置。利用化学药剂对污泥进行深度脱水处理可使污泥减量化、稳定化。为提高深度脱水效果,对添加剂进行了种类和添加量的优化研究(石灰、工业石灰、粉煤灰、硅藻土、十二烷基磺酸钠和飞灰;5%、10%、15%、20%、25%和30%),另外,还进行了复合投加实验。研究结果表明,石灰、工业石灰、粉煤灰的深度脱水效果最好;复合添加中,25%石灰+5%粉煤灰,20%石灰+10%粉煤灰,10%石灰+20%粉煤灰的深度脱水效果最好。5%的石灰或者工业石灰的添加剂量使干化污泥pH值达到12.25,粉煤灰、硅藻土、十二烷基磺酸钠和飞灰的添加对干化污泥pH值影响相对要小。 相似文献
955.
Ying Su Xiulin Wang Keqiang Li Shengkang Liang Guodong Qian Hong Jin Aiquan Dai 《Environmental science and pollution research international》2014,21(17):10067-10082
At present, the monitoring network of China cannot provide sufficient data to estimate land-based pollutant loads that enter the sea, and estimation methods are imprecisely used. In this study, the selection of monitoring stations, monitoring frequency, and pollutant load estimation methods was studied in Qingdao City, a typical coastal city in China, taken as an example. Land-based pollutant loads from Qingdao were estimated, and load distribution, density, and composition were analyzed to identify the key pollution source regions (SRs) that need to be monitored and controlled. Results show that the administrative land area of Qingdao can be divided into 25 sea-sink source regions (SSRs). A total of 14 more rivers and 62 industrial enterprises should be monitored to determine the comprehensive pollutant loads of the city. Furthermore, the monitoring frequency of rivers should not be less than three times/year; a monitoring frequency of five or more times is preferable. The findings on pollutant load estimation with the use of different estimation methods substantially vary; estimation results with the use of ratio-based methods were 10 and 22 % higher than those with the use of monitoring-based methods in terms of chemical oxygen demand (COD) and total nitrogen (TN), respectively. None-point sources contributed the majority of the pollutant loads at about 70 % of the total COD and 60 % of the total TN. 相似文献
956.
De-Yin Huang Chuan-Ping Liu Fang-Bai Li Tong-Xu Liu Cheng-Shuai Liu Liang Tao Yan Wang 《Environmental monitoring and assessment》2014,186(6):3351-3364
We studied the profiles, possible sources, and transport of polycyclic aromatic hydrocarbons (PAHs) in soils from the Longtang area, which is an electronic waste (e-waste) recycling center in south China. The sum of 16 PAH concentrations ranged from 25 to 4,300 ng/g (dry weight basis) in the following order: pond sediment sites (77 ng/g), vegetable fields (129 ng/g), paddy fields (180 ng/g), wastelands (258 ng/g), dismantling sites (678 ng/g), and former open burning sites (2,340 ng/g). Naphthalene, phenanthrene, fluoranthene, pyrene, chrysene, and benzo[b]fluoranthene were the dominant PAHs and accounted for approximately 75 % of the total PAHs. The similar composition characteristics of PAHs and the significant correlations among individual, low molecular weight, high molecular weight, and total PAHs were found in all six sampling site types, thus indicating that PAHs originated from similar sources. The results of both isomeric ratios and principal component analyses confirmed that PAHs were mainly derived from the incomplete combustion of e-waste. The former open burning sites and dismantling sites were the main sources of PAHs. Soil samples that were taken closer to the point sources had high PAH concentrations. PAHs are transported via different soil profiles, including those in agricultural fields, and have been detected not only in 0- to 40-cm-deep soil but also in 40 cm to 80 cm-deep soil. PAH concentrations in soils in Longtang have been strongly affected by primitive e-waste recycling, particularly by former open burning activities. 相似文献
957.
大气污染影响下凯里植物氮、硫含量分析 总被引:1,自引:0,他引:1
对大气污染影响下凯里植物氮、硫质量分数进行测定分析。结果表明:植物的氮质量分数为0.8%~2.8%,平均值为1.5%;硫质量分数为0.4%~1.4%,平均值为0.8%。植物的氮、硫质量分数都高于对照点植物,为对照点植物的1.4倍、1.9倍,表明该区植物已受到了大气污染的影响。不同植物间的氮、硫质量分数差异达到3.5倍和2.5倍。不同类型植物的氮、硫质量分数也存在差异,氮质量分数中:藤本>草本>灌木>乔木,硫质量分数中:藤本>草本>乔木>灌木;落叶植物的氮、硫质量分数>常绿植物的氮、硫质量分数。不同研究点植物的氮、硫质量分数存在差异,均表现为:玻璃厂>火电厂>水泥厂。 相似文献
958.
959.
河流水环境质量综合评价方法比较研究 总被引:12,自引:0,他引:12
提出了对河流水环境质量综合评价方法的基本要求,对水环境质量评价方法的现状进行了研究,并通过对各种方法的 比较,探讨了今后水环境质量综合评价方法的发展方向。 相似文献
960.
Catalan L Liang V Johnson A Jia C O'Connor B Walton C 《Environmental monitoring and assessment》2009,156(1-4):37-49
Emissions of reduced sulphur compounds (RSCs) from the primary and secondary clarifiers at a Kraft mill were measured for respectively 8 and 22 days using a floating flux chamber. In the primary clarifier, dimethyl disulphide (DMDS) had the highest mean flux (0.83 microg s(-1) m(-2)) among all RSCs, and the mean flux of total reduced sulphur (TRS) was 1.53 microg s(-1) m(-2). At the secondary clarifier, dimethyl sulphide (DMS) had the highest mean flux (0.024 microg s(-1) m(-2)), and the mean flux of total reduced sulphur (TRS) was 0.025 microg s(-1) m(-2). Large variations in fluxes as a function of sampling date were observed in both clarifiers. Emission fluxes of DMS from the secondary clarifier were correlated with temperature in the flux chamber and with the biological and chemical oxygen demands (BOD and COD) of the wastewater. Emission rates of RSCs from the clarifiers were found to be insignificant by comparison with other mill sources. 相似文献