Zhang K.,Beijing Normal University |
Liu R.,Beijing Normal University |
Zhang Z.,Beijing Normal University |
Hu L.,Nanyang Environmental Protection Bureau |
And 2 more authors.
Yingyong Jichu yu Gongcheng Kexue Xuebao/Journal of Basic Science and Engineering | Year: 2014
Abrupt water pollution accidents have occurred frequently and caused huge environmental and economic damages. Environmental risk assessment in river basin scale could provide an useful tool for preventing or mitigating such accidents. However, there are some obstacles met when dealing with multiple risk sources(stressors) and multiple risk receptors in such a large spatial scale. A new method, originated from the Relative Risk Model(RRM) in regional scale ecological risk assessment, was presented to address these problems. The framework of RRM was adopted and the ranking procedure was improved in the method. Using more specific information, quantitative models are constructed to estimate likelihood and severity of risk elements with the help of water quality models and GIS tools. The method was applied in the Laoguan River, a tributary of Danjiangkou Reservoir as the major source for South-to-North water diversion in China. The resultant risk map shows that risk increases along with flow direction. Risk management in the river basin should give priority attention to risk sources of tailing ponds upstream and risk receptor of the water body. A relative error of 4.9% partially verified the robustness and stability of the method in uncertainty analysis and sensitivity analysis.
Liu S.-Y.,Zhongnan Diamond Co. |
Zhang Y.-B.,Zhongnan Diamond Co. |
Yuan N.-N.,Zhongnan Diamond Co. |
Ning J.,Nanyang Environmental Protection Bureau |
Li Q.,Nanyang Environmental Protection Bureau
Jingangshi yu Moliao Moju Gongcheng/Diamond and Abrasives Engineering | Year: 2014
Combined with the wastewater problems in diamond production and the process requirements of circulating water, the process of wastewater recycling treatment is discussed. Results show that by adding alkali, heavy metal becomes precipitation which can be filtrated physically, while waste water becomes recycling water, with its pH higher, containing trace amount of Ni and high concentration of NaCl. Waste acid in reactor are collected and recycled. The electrolytic bags are drained when taken out of the electrolytic cell. The electrolytic material are collected as well. Thus both directions of accumulation and osmosis are controlled, although some fresh water are slightly added. In this way the production pollutes none but earns both environmentally and economically.