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401.
造纸污泥固化/稳定化处理技术研究   总被引:4,自引:2,他引:2  
为了能更好地无害化处理造纸污泥,对造纸污泥的固化/稳定化处理技术进行了研究。以水泥、粉煤灰和煤渣作为固化剂对造纸污泥进行固化/稳定化处理。通过抗压强度评价污泥固化块的力学性质;并对固化块浸出液的COD浓度与重金属质量浓度进行了检测。当水泥、粉煤灰和煤渣的掺量分别为0.12、0.02和0.10 kg/kg,养护时间为6 d时,固化块抗压强度达到360 kPa。结果表明,水泥和煤渣对提高造纸污泥固化块的抗压强度具有促进作用,而它们与粉煤灰对造纸污泥中的有机质和重金属均具有一定的固化作用。在以上条件下,固化块浸出液中COD浓度约为115.7 mg/L,重金属浓度符合国家标准。经养护后的固化块含水率均保持在35%~40%,符合填埋场的进场标准。  相似文献   
402.
介绍了中小型工业窑炉生产过程中排放NOx的现状,并针对NOx的治理问题,从工程应用角度,简述了湿法和干法净化NOx的原理和化学反应过程。讨论了NOx排放特性和NOx废气中NO2/NOx比例的问题。提出了影响NOx治理的主要因素,包括吸收剂、吸附剂、催化剂和设备的部分应用参数,并结合工程实例指出工程需要注意的问题。介绍了多项采用湿法和干法净化NOx的工程应用项目,丰富了中小工业窑炉NOx废气的治理的实践经验,为中小工业窑炉排放NOx治理奠定了基础。  相似文献   
403.
硫酸锰渣污染土壤中重金属的形态分布及生物活性   总被引:1,自引:0,他引:1  
测定了硫酸锰渣污染土壤中Cu,Zn,Cd,Pb,Mn的总量和各形态含量.结果表明重金属总量远超过环境背景值和土壤环境二级标准.重金属各形态分布特征:Cu,有机态>残渣态>铁锰氧化态>碳酸盐态>可交换态;Zn,残渣态>铁锰氧化态>有机态>碳酸盐态>可交换态;Cd,铁锰氧化态>可交换态>碳酸盐态>残渣态>有机态;Pb,铁锰氧化态>残渣态>有机态>碳酸盐态>可交换态;Mn,铁锰氧化态>残渣态>可交换态>有机态>碳酸盐态.重金属的生物可利用性系数和迁移系数均为Cd>Mn>Pb>Cu>Zn.  相似文献   
404.
Cd、Ni单一及复合污染对土壤酶活性的影响   总被引:4,自引:0,他引:4  
采用外源添加重金属和露天盆栽实验研究了Cd、Ni对含羞草、三叶草根际土壤脲酶、过氧化氢酶和蔗糖酶活性的影响。结果表明,Cd、Ni单一污染条件下,低浓度的Cd、Ni对含羞草组、三叶草组的脲酶、过氧化氢酶有激活作用,高浓度的Cd、Ni对土壤脲酶、过氧化氢酶有一定的抑制作用;对蔗糖酶有较强的抑制作用。在Cd、Ni复合污染条件下,对含羞草组、三叶草组的脲酶、过氧化氢酶和蔗糖酶产生抑制作用;Cd、Ni单一及复合污染对土壤酶活性的抑制大小顺序为:脲酶>蔗糖酶>过氧化氢酶,其中土壤脲酶可以作为Cd、Ni污染的预警指标。含羞草能显著提高土壤脲酶、过氧化氢酶和蔗糖酶的活性,修复能力大于三叶草,在Cd、Ni污染修复方面有很好的应用前景。  相似文献   
405.
Tapered element oscillating microbalances equipped with sample equilibration system (TEOM-SES) used by the province of Ontario for the ambient monitoring of PM2.5 (particulate matter with an aerodynamic diameter ≤2.5 µm) in its air quality index (AQI) network were collocated with the Synchronized Hybrid Ambient Real-time Particulate monitor (SHARP 5030) at two monitoring sites for a period spanning approximately 2 years to determine the similarities and differences between the measurement outputs of both instrumental systems. Due mainly to mass loss observed with the TEOM-SES in cooler months, the province has recently switched its PM2.5 instrumentation at all stations in its monitoring network from the TEOM-SES to the SHARP 5030, which has the U.S. Environmental Protection Agency (EPA) Federal Equivalent Method (FEM) Class III designation. Thus, it has become imperative to develop corrections for historical and future TEOM measurements for the purpose of making them more agreeable to the new FEM method. This work details the authors’ multiple linear regression analyses (MLRAs) of particulate matter data from both instrumental monitors, with the inclusion of operational parameters of physicochemical relevance for both cases of transformations of historical TEOM and TEOM measurements to be made in the future. For historical TEOM data, it was observed that the transformations only benefited winter and fall months. Furthermore, comparisons of the transformed historical TEOM data with PM2.5 concentrations determined from the Federal Reference Method (FRM) sampler at seven locations within the province showed marked improvements over the observed TEOM-FRM comparisons.

Implications:This work provides a path to correcting the historically observed underreporting of particulate mass in winter and fall in Ontario by making the TEOM-based continuous data resemble the new FEM outputs (in this case, more SHARP-like). It is possible that the transformation of mainly winter TEOM data as detailed in this work may potentially lead to revisions in historical annual composite mean PM2.5 concentrations and total annual number of days PM2.5 exceeded the Canada-wide Standard (CWS) metric across the province.  相似文献   

406.
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   
407.
Breast milk is a noninvasive specimen to assess maternal and infant exposure to polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs). In this study, 206 breast milk samples were collected from 87 participants during lactation, at <7, 15, 30, or 90 days postpartum in four cities in Korea. The total concentrations of PCBs (ΣPCB) and OCPs (ΣOCP) ranged from <LOQ to 84.0 (median: 12.1) ng g−1 lipid weight and from <LOQ to 559 (median: 144) ng g−1 lipid weight, respectively. The residue levels of these contaminants measured in our study were relatively lower than those reported for European, African and Asian populations. Within a month postpartum typically after day seven the levels of ΣPCB and ΣOCP significantly increased. Some OCP compounds were correlated with maternal age, BMI, parity, and delivery mode. Certain types of dietary habits such as seafood and noodle consumption were significantly associated with ΣPCB and ΣOCP. The estimated daily intakes (EDIs) of ΣPCB and ΣOCP were 45.2–127 ng kg−1 bw day−1 and 625–1259 ng kg−1 bw day−1 during lactation, respectively, which are lower than the threshold values proposed by the US EPA and Health Canada. The exposure of Korean infants to chlordanes via breast milk had a potential health risk which deserves further investigation.  相似文献   
408.
沉淀——吸附法处理果胶工艺废水   总被引:1,自引:0,他引:1  
利用果胶废水中的Al(Ⅲ)和石灰乳沉淀,并用炉渣、活性碳脱色的方法,处理盐板法提取果胶的工艺废水。通过正效实验,研究了最佳工艺条件。该工艺处理后的废水,Al(Ⅲ)去除率96.8%,CODCr去除率为92.7%,SO4^2-去除率为61.5%,且废渣产出量少。  相似文献   
409.
Environmental assessments are often performed for industries due to a lot of issues produced in the processes. However, few studies are reported for environmental assessment of Chinese liquor production. A lot of material consumptions in Chinese liquor industries often bring about serious environmental pollution. Thus, Chinese strong aromatic liquor (CSAL) is taken as a representative for the environmental issues assessment of Chinese liquor industry in view of cleaner production (CP). The assessment is performed for the brewing system of CSAL including three main phases: crude liquor brewing, crude liquor blending, and steam production, which addresses resource and energy consumptions and environmental impacts. The results indicate that, according to the standards of Ministry of Environmental Protection of China, the consumptions of materials and energy are acceptable while the water consumption is higher than the requirement. Moreover, the discharge of chemical oxygen demand (COD) in the brewing phase is above the standard requirement and contributes much to eutrophication. The total environmental impacts in the blending phase are less than those in the brewing and steam production phases. In detail, in the brewing phase, high concentration of volatile organic compounds in the wastewater results in the odor threshold values and photochemical ozone creation. In the blending phase, the main environmental impact is eutrophication owing to the wastewater. In the steam production phase, the most and least significant impacts are global warming and soot emission, respectively, wherein waste gas emission is dominated. Cost analysis reveals that when the water consumption and COD discharge meet the requirements according to the CP option, there are plenty of economic and environmental benefits for the CSAL industry. The results confirm that the reform strategies for the Chinese liquor enterprise should be performed to decrease the water consumption, promote the utilization efficiency of water, improve recycle and reuse of by-products, reduce the pollutant discharge, and enhance waste treatment efficiency.  相似文献   
410.
环境标准实施中的若干问题   总被引:3,自引:0,他引:3  
探讨了目前环境标准在制订、发行、宣贯过程中存在的问题 ,并就规范环境标准发布、加强标准宣贯等提出建议  相似文献   
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