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421.
韶钢2200 m3高炉投产运行近16年,处于炉役后期生产,受操作炉型不规则且炉缸保温性能极大下降等影响,高炉休风检修后,炉况恢复较困难。通过科学调剂精料管理、优化休风料加入方式、上下部操作制度并改进造渣制度和出铁模式等一系列措施,实现了高炉在短时间内快速恢复炉况的目的。  相似文献   
422.
Keratinous wastes could be degraded by some microorganisms in nature. Native human foot skin (NHFS) was used as sole nitrogen source to screen microorganisms with keratin-degrading capability. From approximately 200 strains, a strain of Streptomyces sp. strain No. 16 was found to possess the strongest keratinolytic activity, and the total activity in the culture was 110 KU/ml with specific activity of 2870 KU/mg protein (KU: keratinase unit). Substrate specificity test indicated that the crude keratinase could degrade keratin azure, human hair, cock feathers and collagen. The optimal pH of the crude keratinase ranged from 7.5 to 10 and the temperature ranged from 40℃ to 55℃. Metal chelating agent ethylenediamine tetraacetic acid obviously stimulated the keratinolytic activity but suppressed the proteolytic activity. To our knowledge, this is the first report on specific induction of keratinases by NHFS from an actinomycete. Moreover, excellent characteristics of its crude keratinase may lead to the potential application in waste treatment and recovery, poultry and leather industry, medicine, and cosmetic development.  相似文献   
423.
校园一次性废电池回收关键环节的问卷调研   总被引:1,自引:1,他引:0  
如何从分散的大量用户手中回收一次性废电池是目前一次性废电池回收体系构建中的关键环节。文章采用问卷调查方法,以华东师范大学中山北路校区在校本科生为对象,研究了针对校园大学生用户回收一次性废电池环节中的存在问题和解决。提出了"以旧换新"的回收方式,初步确定了该方式运行所需的几个关键参数:回收的"旧新电池回收比例"为5:1,回收地点在各宿舍管理员处,回收时间为每月定期进行一次。文章结果对于构建废电池回收体系具有一定的参考意义。  相似文献   
424.
This article analyses the impact of waste recovery on climate change mitigation on a regional scale. We focus on the EU End of Waste (EoW) policy, which aims at reducing negative impacts on the environment through the minimization of generated waste. At the same time, the EU climate objectives set challenging goals for the industry to lower greenhouse gas emissions. We argue that the goals of these two policies are conflicting: under certain circumstances, the EoW will lead into increased greenhouse gas emissions because of a number of negative feedback effects that function on multiple spatial and temporal scales.To assess the effects of waste recovery on greenhouse gas emissions, we carry out a consequential life-cycle inventory on a proposed industrial ecosystem around the Gulf of Bothnia between Finland and Sweden. The system recovers currently unutilized steelmaking dust and slag from four steel mills in Finland and Sweden and converts them into iron and zinc raw materials in a novel rotary hearth furnace. The recovered iron is led back into the blast furnace of one of the steel mills and zinc is treated in an existing zinc plant. In the European scale, the model system is significant in size, serving thus as a model for integrated EoW and carbon footprint assessments in other similar cases within the EU.The analysis reveals the relative greenhouse gas emissions from raw material extraction and production, heat and power generation, transport and the production process itself, in comparison to the present system with limited material recovery. To test the model viability, we conduct a sensitivity analysis with respect to increasing energy and production capacity. Our analysis shows that from the point of view of a single operator, material recovery may bring noteworthy reductions in greenhouse gas emissions. If the scale of the assessment is expanded beyond the confines of a single plant, however, we find limited potential for reducing greenhouse gas emissions through further recovery of steelmaking residues. In conclusion, we provide policy recommendations with which the EoW paradigm can provide better support for climate change mitigation on a regional scale.  相似文献   
425.
The objective of this paper is to assess the environmental effectiveness of a strategic measure aimed at resource productivity enhancement. The cement industry has been identified as a relevant sector for this global issue, since the related production process enables the use of waste in partial substitution of raw materials and in substitution of traditional fuels. The analysis of the cement production sector in Italy has been here performed, investigating the recovery of energy from waste through co-incineration. In terms of air emissions, the emission performances of cement kilns appear independent from the use of alternative fuels at the percentages usually employed. However, in order to measure the cleanliness of a production system, systematic analysis with global perspective is needed. For this aim, the principles of Life Cycle Assessment (LCA) have been used for a case study analysis of an Italian active plant using an amount of recovered plastics as an alternative fuel resource. The improvement on the investigated process has been quantitatively measured as a way for cleaner production, first in terms of gross energy requirement, and then through an environmental performance comparison with a sector benchmark. The analysis has highlighted the benefits on the global environmental balance for the practice of co-incineration in the cement production process.  相似文献   
426.
油气田压裂返排液治理技术研究现状   总被引:4,自引:0,他引:4  
李兰  杨旭  杨德敏 《环境工程》2011,29(4):54-56,70
概述了压裂的目的、压裂液以及压裂返排液的来源和和水质特征。综述了近十年来絮凝沉降法、生物及生化法、高级氧化技术和Fe/C微电解组合工艺的水处理作用原理及其在压裂返排液治理中的应用进展。分析并指出了压裂返排液处理技术中存在的问题和今后的主要发展方向。  相似文献   
427.
"微滤+反渗透"工艺在处理垃圾渗滤液中的应用研究   总被引:1,自引:0,他引:1  
采用"多孔陶瓷微滤+两级反渗透"工艺处理垃圾渗滤液.分别考察多孔陶瓷微滤膜、一级反渗透和二级反渗透对渗滤液COD、NH3-N、电导率及相应去除率与运行时间的关系,还重点考察了一级反渗透系统回收率控制及清洗周期和方法.研究结果表明:经过陶瓷微滤预处理后,出水的COD、NH3-N去除率、脱盐率分别维持在50.3%、30.2...  相似文献   
428.
根据油库油气回收系统的工艺要求,分析了现有油库上装发油系统实现油气密闭收集的技术难点及需要解决的问题。借鉴下装式发油的技术特点,研发了上装密闭发油系统,提出了鹤管系统及油罐车改造方案。在对现有油库上装发油鹤管不进行大规模改造的前提下,实现了上装密闭发油,经现场应用,效果良好。  相似文献   
429.
This study examines how pre‐existing disabling conditions influenced the recovery process of survivors of Hurricane Katrina. It focuses specifically on the barriers that hindered the recovery process in these individuals. Focus groups were convened in four Gulf Coast states with 31 individuals with disabilities who lived in or around New Orleans, Louisiana, prior to Hurricane Katrina in August 2005. Qualitative data were analysed using grounded theory methodology. Five themes emerged as the most significant barriers to recovery: housing; transportation; employment; physical and mental health; and accessing recovery services. While these barriers to recovery were probably common to most survivors of the disaster, the research results suggest that disability status enhanced the challenges that participants experienced in negotiating the recovery process and in acquiring resources that accommodated their disabilities. The findings indicate that, when disaster recovery services and resources did not accommodate the needs of individuals with disabilities, recovery was hindered. Recovery efforts should include building accessible infrastructure and services that will allow for participation by all.  相似文献   
430.
Peter M. Lawther 《Disasters》2016,40(3):494-517
Contemporary responses to facilitate long‐term recovery from large‐scale natural disasters juxtapose between those of humanitarian agencies and governments and those of the affected community. The extent to which these mechanisms articulate is crucial to the recovery propensity of the affected communities. This research examines such action by exploring the relationship between the scale of post‐disaster response interventions, the extent of community participation in them, and their impact on community recovery, using a community wealth capital framework. The investigation was applied to a study of the longer‐term community recovery of the island of Vilufushi, Republic of Maldives, which was almost completely destroyed by the Indian Ocean tsunami of 26 December 2004. Data were analysed through the employment of a pattern match technique and a holistic recovery network analysis. The research framework, informed by the case‐study results, other long‐term recovery evaluations, and existing resilience theory, is reconfigured as a testable roadmap for future post‐disaster interventions.  相似文献   
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