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631.
While the presence of lead in urban soils from residential lead paint and leaded gasoline is well documented, the relative contribution of lead from area historical industrial activities is not. This study examined the connection between historical industrial sources of lead in Portland, Maine, USA from 1860 to 1970 to current, spatial distributions of soil lead. Collecting 1859 surface and 122 sub-surface soil samples in accordance with USEPA's Lead Safe Yard Protocols, lead concentrations varied from 9 mg/kg to >100,000 mg/kg with most of the samples greater than USEPA's critical value for lead (400 mg/kg). Using historical documents, probable sources of lead were mapped. In comparing two datasets, no clear relationship emerged. Findings were hampered by inability to sample under large areas of impervious surfaces and private properties. Because of lead's immobility in soil, one would expect decreasing concentration with depth, but lead concentrations varied with depth and location. The haphazard dumping of lead-contaminated industrial waste and the relocation of contaminated fill are likely factors. These findings suggest that in urban areas where multiple historical sources of lead existed, surface sampling to determine presence of lead may not be sufficient to protect public health.  相似文献   
632.
Wastewater produced from a metal plating is a major environmental problem. Industrial auditing revealed that the main source of pollution mainly originated from rinsing water. The characterization of final effluent showed that it is highly contaminated with hazardous heavy metals and cyanide. The concentration of copper, hexavalent chromium, nickel, and cyanide in the rinsing water of metal plating department was 14.8, 40.9, 13.3, and 19 mg/l, respectively. The concentration of cyanide and zinc from the galvanizing department reached 60 and 80 mg/l. The remediation scheme included the application of in-plant control measures via changing the rinsing process followed by the destruction of cyanide and reduction of hexavalent chromium bearing wastes. The pretreated wastes were then mixed with other industrial wastes prior to a combined chemical coagulation-sedimentation using lime and/or lime in combination with ferric chloride. The results indicated that, after applying the waste minimization measures alone at the source, prior to final treatment of industrial waste, removal rates of cyanide, copper, nickel, and chromium concentrations were 23.2%, 14.9%, 32.3%, and 55.3%, respectively in the rinse water from metal plating department. Furthermore, the removal rates of cyanide and zinc in the galvanizing department reached 59.7% and 24.3. The integrated control measures and treatment scheme led to more than 99% removal of copper, nickel, chromium, and zinc, while the complete removal of cyanide was achieved in the final effluent.  相似文献   
633.
The status of wild capture fisheries has induced many fisheries and conservation scientists to express concerns about the concept of using forage fish after reduction to fishmeal and fish oil, as feed for farmed animals, particularly in aquaculture. However, a very large quantity of forage fish is being also used untransformed (fresh or frozen) globally for other purposes, such as the pet food industry. So far, no attempts have been made to estimate this quantum, and have been omitted in previous fishmeal and fish oil exploitation surveys. On the basis of recently released data on the Australian importation of fresh or frozen fish for the canned cat food industry, here we show that the estimated amount of raw fishery products directly utilized by the cat food industry equates to 2.48 million metric tonnes per year. This estimate, plus the previously reported global fishmeal consumption for the production of dry pet food suggest that 13.5% of the total 39.0 million tonnes of wild caught forage fish is used for purposes other than human food production. This study attempts to bring forth information on the direct use of fresh or frozen forage fish in the pet food sector that appears to have received little attention to this date and that needs to be considered in the global debate on the ethical nature of current practices on the use of forage fish, a limited biological resource.  相似文献   
634.
Background The aim of the project was to measure the actual emissions of PCDD/F, PCBs and HCB from 20 selected metallurgical installations in Poland, in order to update the national inventory of dioxin emission from metallurgical industry for developing a strategy for dioxins and furans emission abatement from the subject facilities (UNEP 2005). Methods Sampling methodology used in this work was developed at the Cracow University of Technology because of the complexity of simultaneous sampling and determining PCDFs, PCDDs, PCB and HCB. For the determination a GC-MS/MS system was used. Results and Discussion Results from the work indicate that the highest dioxins and PCB concentrations were recorded for iron ore sintering plants at 1.10–1.32 ng total1 TEQ/Nm3 followed by aluminium scrap melting at 0.03–0.66 ng total TEQ/Nm3. The highest HCB concentrations at 613–1491 ng/Nm3 were also recorded for iron ore sintering plants, whereas at aluminium plants the HCB concentrations were in the range of only 10.1–22.7 ng/Nm3. Conclusions The above investigations indicate that secondary aluminium production is the most significant dioxins source, if calculated as emission factor values. However, iron ore sintering plants are operating at much higher production capacity, causing this process to become the major source of dioxins, PCB and HCB pollution to the atmosphere in Poland. Recommendations and Perspectives Based on the performed tests and the environmental reviews of selected plants several recommendations were formulated for the reduction of generation or of emission of these pollutants from iron ore sintering plants, electric arc furnace steel production processes, hot-blast furnace operations, secondary aluminium smelting and primary zinc production from zinc cathodes.  相似文献   
635.
In all tanning technology operations wastes are generated. These reach the environment as residual waters, solid and liquid waste as well as atmospheric emissions and odours.

This study tests an alternative method to the traditional tanning method at an industrial level. The new method is based on tanning without float and by significantly increasing the temperature at the end of the tanning process. The properties of the leathers obtained using the two methods have been compared and the results indicate that those leathers have similar physical, chemical, and organoleptic properties. However, the differences existing from the environmental point of view are significant. It is not necessary to use clean water for this tanning. Moreover, there is a 75% reduction of the residual float, a 91% reduction of the chrome discharged, and a 94% reduction of the chlorides discharged. A financial assessment was carried out to demonstrate that the newly proposed system is 32% more economic than the traditional one.  相似文献   

636.
我国纺织工业建设项目清洁生产评价要点探析   总被引:1,自引:0,他引:1  
结合国际纺织工业“生态化”发展的态势以及我国纺织化工业发展特点,考虑建设项目环境评价对清洁生产的要求,提出了我国纺织工业建设项目清洁生产评价的要点。从厂址、产品、工艺、设备、资源利用、环境安全等角度构建纺织工业建设项目清洁生产评价指标体系。  相似文献   
637.
本文在专家咨询和层次分析的基础上,提出了常德市乡镇工业行业结构调整方案。将层次分析所得各行业优先权重与行业结构状态相耦合,不仅定性地提出了调整方向,而且定量地提出了调整幅度。  相似文献   
638.
企业绿色竞争力是企业在“绿色化”的前提下,与对手相比的一种竞争优势。石油和化工行业是能源和资源的生产和消耗大户.也是众所周知的重污染行业.对石油和化工企业的绿色竞争力进行实证研究具有重要意义。本文以长三角地区的石油和化工行业上市公司为案例。构建基于DEA法的绿色竞争力评价模型.评估了它们的绿色竞争力。实证结果显示:长三角地区石油和化工企业的绿色竞争力还有待加强.在此基础上提出了石油和化工企业提高绿色竞争力的一些具体措施。  相似文献   
639.
目前,各级地方政府及旅游经营者对中国世界自然遗产地旅游价值的开发力度大,自然遗产地旅游经济发展异常繁荣,同时也带来了自然遗产地环境退化、资源破坏的严重后果。而用来衡量地区经济发展状况的传统旅游业经济核算结果仅体现旅游经济的增长与否及尺度,而忽略了旅游经济增长同时的环境、资源损耗。现借用SEEA 2000框架,结合中国国情,提出中国世界自然遗产地环境经济核算的框架,经过重新整合,突出优质而独具特色的自然环境部分的环境资产类在自然遗产地旅游业中的生产性资产地位,将原SEEA 2000中拆分核算的5大部分、10大步骤整合为4大部分、9大步骤,并对其当前可操作性进行了客观分析。并指出,虽然目前详尽执行世界自然遗产地环境经济核算有一定难度,但理清核算思路具有现实指导意义。  相似文献   
640.
根据锦州地区71家冶金企业污染现状的调查研究,发现主要为废气污染,占全市废气污染源排放量的18%。其中,废气中的粉尘污染占全地区的41%,二氧化硫污染仅次于火电行业,在冶金企业相对集中的凌海市和太和区所占比例超过80%。针对这一严重污染问题,从宏观调整布局到具体管理等方面提出应采取的污染治理措施,为实现污染管理和达标排放提供有效保障。  相似文献   
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