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清洁生产审核中目标的设置是完成审核的重要环节之一,但是由于没有定量的手段往往会出现高低偏差,以至影响审核的效果。围绕此问题,本文探讨了借助计量经济软件Eviews对相关数据建立模型,以贵阳特殊钢有限责任公司一炼钢厂钢产量和电耗为例,预测未来电耗情况,结合相应清洁生产方案设置审核的目标。 相似文献
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Jie Fu Zhen Xu Qing-Shan Li Song Chen Shu-Qing An Qing-Fu Zeng Hai-Liang Zhu 《环境科学学报(英文版)》2010,22(4):512-518
A comparative study of treatment of simulated wastewater containing Reactive Red 195 using zero-valent iron/activated
carbon (ZVI/AC), microwave discharge electrodeless lamp/sodium hypochlorite (MDEL/NaClO) and the combination of ZVI/ACMDEL/
NaClO was conducted. The preliminary results showed the two steps method of ZVI/AC-MDEL/NaClO had much higher
degradation e ciency than both single steps. The final color removal percentage was nearly up to 100% and the chemical oxygen
demand reduction percentage was up to approximately 82%. The e ects of operational parameters, including initial pH value of
simulated wastewater, ZVI/AC ratio and particle size of ZVI were also investigated. In addition, from the discussion of synergistic
e ect between ZVI/AC and MEDL/NaClO, we found that in the ZVI/AC-MEDL/NaClO process, ZVI/AC could break the azo bond
firstly and then MEDL/NaClO degraded the aromatic amine products e ectively. Reversing the order would reduce the degradation
e ciency. 相似文献
856.
深圳荔枝湖富营养化综合治理工程效果研究 总被引:1,自引:0,他引:1
分析和比较了深圳荔枝湖综合治理工程运行9个月内不同湖区水体的叶绿素a、总磷、总氮及透明度的变化,探讨了综合治理工程对城市富营养化湖泊荔枝湖的水质改善情况.结果表明,治理工程运行期间全湖湖水营养水平控制在较低水平(总磷<0.1 mg·L-1,总氮<1.5 mg·L-1),四湖区藻类水平北湖区(16.77μg·L-1)和东湖区(21.45μg·L-1)较低,南湖区(35.83μg·L-1)、西湖区(32.69μg·L-1)相对较高,全湖水体透明度提高(全湖平均>0.5 m);治理工程将湖水水质由劣Ⅴ类改善为Ⅳ类,由重富营养化水平改善为富营养化水平. 相似文献
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An evaluation of a river health using the index of biological integrity along with relations to chemical and habitat conditions 总被引:13,自引:0,他引:13
We evaluated the health condition of a temperate river during June-November 1999 through applications of the index of biological integrity (IBI) using fish assemblages and qualitative habitat evaluation index (QHEI) as well as chemical analyses. Overall IBI values ranged from 13 to 37 and averaged 23 (n = 25, standard error = 1.16), indicating a "poor" or "very poor" condition according to the criteria of modified Karr [Fisheries 6 (1981) 21]. The values of mean IBI declined at a rate of 0.22 km(-1) (R2 = 0.91, p < 0.05) along the longitudinal distance from the headwaters to the downstream sites. Reduced IBI values at downstream sites reflected low forest cover, high population density and high nutrient enrichments. Ecotoxicity tests using the river water also showed that toxic impacts were evident in the downriver sites. These factors resulted in decreases of riffle benthic species and insectivores and increases of tolerant species, anormalies and exotic species in the river. Spatial pattern in IBI agreed with QHEI values, which showed a linear relation (R2 = 0.998, p < 0.001) with species richness. Field measurements of conductivity and pH, an indicators for variation of conservative ions, showed that the river water was diluted by 40% fold by summer monsoon rain and surface run-off from the watershed, resulting in a physical and chemical instability during the monsoon. For these reasons, average IBI values during the monsoon and postmonsoon decreased >20% compared to the premonsoon, indicating that IBI values were also affected by flow regime. Based on the overall physico-chemical data and IBI values, the river health is rapidly degrading due to the combined effect of chemical contaminations and habitat modifications. 相似文献