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351.
SO_2 in flue gas needs to be eliminated to alleviate air pollution. As the quality of coal decreases and environmental standard requirements become more stringent, the highefficiency desulfurization of flue gas faces more and more challenges. As an economical and environmentally friendly solution, the effect of calcium formate as an additive on desulfurization efficiency in the wet flue gas desulfurization(WFGD) process was studied for the first time. Improvement of the desulfurization efficiency was achieved with limited change in p H after calcium formate was added into the reactor, and it was found to work better than other additives tested. The positive effects were further verified in a power plant, which showed that adding calcium formate could promote the dissolution of calcium carbonate, accelerate the growth of gypsum crystals and improve the efficiency of desulfurization. Thus, calcium formate was proved to be an effective additive and can potentially be used to reduce the amount of limestone slurry required, as well as the energy consumption and operating costs in industrial desulfurization.  相似文献   
352.
In this study, the size of tobacco rob (TR) particle was considered as a major factor in determining the mass loss in thermogravimetric analysis (TGA) and product yield and composition at different reactor temperatures in the fixed-bed reactor. The TGA results showed that the conversion rate increased and the activation energy (ranged from 53.29 to 58.25 kJ/mol) decreased with a decrease in particle size. The experiments demonstrated that fuel gas yield (from 0.76 to 0.82 Nm3/kg at 900 °C) increased with a decrease in particle size while char and tar yield decreased. Smaller particle sizes resulted in higher H2 (25.68%) and CO (27.36%) contents. Minimizing the size of raw materials is an alternative method to improve the gas quality of TR pyrolysis. The increase of gas yield was attributed to the decomposition of char and tar vapor as temperature increased.  相似文献   
353.
Objective: Crash test dummies are full-scale anthropomorphic test devices (ATDs) that simulate the dimensions, weight proportions, and articulation of the human body and are used to measure human injury potential in vehicle crashes. The Hybrid III dummy family, which is widely used currently, takes selected percentiles of anthropometry dimensions of U.S. adults as design references. The objective of this study was to assess the difference in anthropometry between Chinese adults and the currently used dummy.

Methods: Based on the Chinese National Physical Fitness Surveillance of the year 2000, 2005, 2010 and National Standard of China GB/T 10000–1988, a series of anthropometric parameters for Chinese adults were obtained, and data analysis was conducted between Chinese adults and ATDs that are currently used.

Results: The comparison revealed distinct anthropometric difference between ATDs and Chinese adults. Based on the latest data, median Chinese females were about 2.6% lower in stature and about 8.03% lower in body weight than the ATD design targets. Similarly, median Chinese males were about 3.48% shorter and weighed 11.89% less than the ATD design targets.

Conclusions: Although the anthropometric differences between Chinese adults and the Hybrid III ATD specifications were modest and growing smaller, it is advisable to take the differences in anthropometry between ATDs and Chinese adults into consideration when developing new vehicles in China to provide effective protection specifically for Chinese occupants.  相似文献   

354.
随着经济发展,农村生活污水治理问题己经成为海南省环境保护突出的问题,为了充分掌握海南省农村生活污水特征,对海南省北部、东部、南部、西部和中部的村庄生活污水产生、排放、污染特征及污水收集现状进行调查,以期为海南省农村生活污水治理提供准确的基础数据。  相似文献   
355.
通过动态试验,考察了反渗透膜制终端直饮水系统对有机物、TDS、氨氮、UV254以及硝酸盐等的去除效果;同时分析了进水UV254与CODMn的相关性。试验表明:该系统对CODMn、TDS与硝酸盐氮的平均去除率分别为60%、95%和86%,出水的氨氮浓度基本为0;该系统对UV254的平均去除率为90%,可保证饮水水质安全;同时试验表明进水UV254与CODMn之间有一定的相关性。  相似文献   
356.
主成分分析法用于环境质量评价的探讨   总被引:4,自引:0,他引:4  
文章将主成分分析法用于某河流水质评价,得出该河流历年水质变化趋势,但得到的水质评价等级却与实际情况不符。通过对主成分分析法原理进行研究,得出两个结论:主成分分析法可用于比较不同时间或不同地点的环境质量优劣;主成分分析法不能评价出环境质量等级。这主要是由主成分分析法的本质特点所决定。  相似文献   
357.
胜利油田自1988年在海上开发第一口探井至今已成功投产油井近400口,年产原油210余万吨,需用90艘各类船舶,从事运输作业,其中2000 t级原油穿梭油轮2艘,1500t成品油轮1艘,800t原油轮2艘,还需外雇船舶42艘,其中油轮13艘,总载重量1万余吨.  相似文献   
358.
海底管线悬空是安全生产、环境保护的重大隐患.在对海底管线悬空原因分析的基础上,介绍了抛填砂袋法、挠性软管跨接法、水下支撑固定法、水工布法及仿生海草技术等方法的应用、特点.实践表明,仿生海草技术根治了滩海海底管道悬空问题,获得了较好的社会效益和经济效益.  相似文献   
359.
根据某水稻精深加工企业废水特点,提出4套废水处理方案,通过技术经济等方面的比较,确定该企业的污水处理方案.认为采用PS-生物流化床法处理企业废水具有工艺合理、运行稳定可靠、处理效率高、投资少、占地面积小等优点,同时给出了废水的预处理效果,及污水处理站的选址.  相似文献   
360.
以杭州湾海底管线为例,提出海底输油管线穿孔溢油安全应急措施。海底输油管线穿孔后,利用抽油泵抽吸,使海底管线内产生负压,阻止管线内原油外溢,利用SCADA系统进行了模拟试验,结果显示:用抽油泵抽吸能使海底管线产生-0.038~-0.04MPa压力,理论上能将海水吸入,阻止原油外泄。  相似文献   
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