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81.
The evolvement of morphology and structure of the coal with different metamorphic degrees during coking process in the vertical furnace was investigated by infrared Image detector. Moreover, the temperature distribution in the radial direction and the crack formation were also studied in heating process. The results show that the amount of crack and the shrinkage level of char decrease with the coal rank rising. In addition, the initial temperature of crack formation for char increases with the coal rank rising.  相似文献   
82.
评述了近年来城市污水生物脱氮除磷理论和功能微生物的研究进展,重点介绍了生物处理的新方法:短程硝化反硝化处理法、厌氧氨氧化处理法、同步硝化反硝化处理法、同步反硝化除磷脱氮法,并总结了各处理工艺的应用状况。对生物脱氮除磷微生物学和新的理论技术发展趋势做出了展望。  相似文献   
83.
针对环境保护企业财务管理中的应收账款和信用管理现状,重点分析了环保企业应收账款的管理方式,通过对模型流程的建立,采用数据挖掘处理技术来有效解决环保企业应收账款信用的分析判断,提高环保企业应收账款财务的整体管理水平。对于提高环保行业的整体良性发展具有借鉴意义。  相似文献   
84.
Use of enzymes in textile processes has many advantages as far as the environmentally friendly processes are concerned. These advantages include water and energy savings, less chemical use, less fabric damage, mild and environmentally friendly process conditions. In this work, C.I. Reactive Yellow 15, C.I. Reactive Red 21 and C.I. Reactive Blue 19 were used to dye untreated woven cotton fabric in a laboratory scale dyeing machine, on a pilot scale jig and on a pilot scale winch by using a single bath combined process, in which various enzymes, namely, amylase, pectinase, and catalase were employed. This new process was named as the “Rapid Enzymatic Single-bath Treatment” (REST), since it was completed almost in half of the conventional dyeing time, and all of the stages, namely, desizing, scouring, bleaching and dyeing were carried out in a single bath without replacing the process water with fresh water until the end of the dyeing. In the REST process, the untreated, starch-sized fabric was first desized by amylase enzyme, and this was followed by a pectinase treatment in the same bath. The fabric was then bleached by H2O2 in the same bath, and after the hydrogen peroxide bleaching; the catalase enzyme was added to the bath to remove H2O2 residues before reactive dyeing. Without carrying out intermediate washings/rinsings between these processes, the reactive dyeing was carried out in a conventional way in the same bath, and finally, the fabric was taken from the bath and washed out. The colour yield was compared with the dyeings which were carried out conventionally in separate baths. Finally, the REST has many benefits in terms of water saving, reduced process time and energy consumptions compared to the conventional preparatory and dyeing process of cotton fabrics.  相似文献   
85.
利用实验室微粒子控制模拟试验装置,采用开放源类粉体物料自由下落溢出随机粉尘的实验研究方法,研究了济南市开放源类粉体物料自由下落过程中微粒子排放规律;在一定动力因素条件下,探讨了物料种类、粒度组成,物料含水率,环境空气湿度,自由下落中质量流量等因素对物料排放率的影响;通过数学归纳和模型化处理,建立了开放源类粉体物料自由下落过程中大气微粒子排放估算的数学模型;通过对实验数据进行回归分析后认为,粒径、含水率是对排放率影响最大的因素,质量流量是对排放率影响最小的因素。经试验验证,计算值与试验值基本一致。所获结论,对开放源类物料在转运、装卸、堆放等操作过程中大气微粒子的排放估算和综合防治具有重要的参考价值。  相似文献   
86.
贾敏 《内蒙古环境科学》2011,(5):99-100,126
我国城市污水处理的现状以及当前全国城市污水厂普遍应用的污水处理工艺,在选择城市污水处理工艺时应考虑资金及土地资源方面的问题,通过开发新型高效污水处理工艺提高污水净化率和污水处理量。同时通过建立和完善城市污水处理制度,提高城市居民环保意识,污水处理走向市场化,实现社会与政府的共赢。  相似文献   
87.
介绍了工艺安全变更管理的概念及相关标准法规,结合国内变更管理的现状,提出了大型乙烯成套装置工艺安全变更管理建议。  相似文献   
88.
采用职业卫生学调查和职业暴露风险评估方法,对选定的苯类物质非密闭操作过程较集中的芳烃装置进行职业暴露分析和评估,为石化企业苯类物质的健康风险控制提供依据。  相似文献   
89.
The accomplishments of inherent safety in the field of loss prevention thus far are impressive due to its scientific philosophy: reducing risks at source rather than adding engineered and procedural protections. Generally, the implementation of inherent safety can be done through a cohesive set of fourteen principles elucidated by Kletz and Amyotte. This work, guided by the fourteen principles, presents a systematic review on the implementation methodologies of inherent safety. Firstly, PRISMA procedure was adopted to select eligible literatures according to inclusive and exclusive criteria. After obtaining the selected literatures, the preference, level of application, and gaps in using these principles were critically analyzed. Of the fourteen principles, intensification, substitution, attenuation, simplification, limitation of effects, and avoidance of knock-on effects are preferable to implementing inherent safety in chemical process. Although the remaining principles are also potentially useful, they are not commonly used due to their costs and complexities of implementation. Overall, this work presents a complete spectrum to look across the implementation methodologies of inherent safety and concludes with some holistic and inclusive approaches as future research recommendations.  相似文献   
90.
CO2资源化利用的现状及前景   总被引:6,自引:2,他引:4  
介绍了CO2分离捕集最新工艺——电化学法、膜法、化学循环燃烧法的研究进展。评述分析了CO2的各种资源化应用前景:CO2气体用作生物碳源、辅助注射成型剂及有机物(如氨基甲酸酯、表面活性剂)合成原料等;液态CO2用于人造金刚石、热泵干燥、超临界CO2萃取及固体干冰冷喷射清洗等。CO2作为一种潜在的丰富碳源,应不断研发其新的应用领域,加快其工业化应用。  相似文献   
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