燃煤锅炉脱汞效率设计计算研究

发布时间：2018-09-11 18:42

【摘要】：燃煤锅炉广泛应用于工业生产过程中,燃煤锅炉的汞污染已经引起了各国政府的高度重视。很多国家都提出了燃煤锅炉汞排放控制标准,很多学者对煤种汞含量和燃煤锅炉的汞排放控制技术进行了研究。目前燃煤锅炉烟气中汞的转化规律理论已基本成熟,在认识清楚转化规律的条件下,国内外学者不仅对现有污染物控制装置的脱汞效率进行了研究,也研究开发出很多脱汞实用技术,文中对相关内容进行了整理分析。结合国内外学者脱汞技术的研究成果,从指导燃煤锅炉脱汞设计计算的角度出发,本文重点对燃煤锅炉常用的污染物控制装置的脱汞效率进行了分析研究。文中收集整理了16个电厂汞质量平衡数据,通过分析研究表明,现常用污染物控制装置中,脱硝装置不能脱除燃煤锅炉烟气中的汞,但能提高除尘装置和脱硫装置汞脱除效率；布袋除尘器比电除尘器脱汞效率高；循环流化床锅炉现有污染物控制装置比煤粉锅炉现有污染物控制装置脱汞效率高。根据研究成果,整理了燃煤锅炉设计计算过程中,常用污染物控制装置脱汞效率选值推荐表。为了能进一步指导燃煤锅炉脱汞设计计算,本文着重研究了燃煤锅炉脱汞效率的计算公式,并从中国汞排放限值标准出发,选取了6个电厂进行了脱汞效率分析。研究表明,现有污染物装置基本能保证脱汞效率控制在中国国家标准要求的限值范围内,对于煤中汞含量较高的中国云贵地区的燃煤锅炉,污染物控制装置的脱汞效率达到90%～95%时,可以控制大多数燃煤锅炉汞排放值达到国家标准限值范围。本文还结合理想气体理论,分析了汞对燃煤锅炉烟气量的实际影响程度,得出汞对烟气量的影响很小,可以忽略不计。
[Abstract]:Coal-fired boilers are widely used in industrial production. Mercury pollution of coal-fired boilers has been paid great attention by governments all over the world. Many countries have put forward mercury emission control standards for coal-fired boilers. Many scholars have studied mercury content of coal and mercury emission control technology of coal-fired boilers. At present, the theory of mercury conversion law in flue gas of coal-fired boiler has been basically mature. Under the condition of clearly understanding the transformation law, domestic and foreign scholars have not only studied the removal efficiency of mercury from existing pollutant control units. Many practical techniques of mercury removal have also been developed, and the related contents have been analyzed in this paper. Based on the research results of mercury removal technology of domestic and foreign scholars, and from the point of view of guiding the design and calculation of mercury removal from coal-fired boilers, this paper focuses on the analysis and study of mercury removal efficiency of pollutants control units commonly used in coal-fired boilers. The data of mercury quality balance in 16 power plants are collected and sorted. The results show that the denitrification unit can not remove mercury from the flue gas of coal-fired boiler, but can improve the removal efficiency of mercury from the flue gas of coal-fired boiler and desulphurization unit. The mercury removal efficiency of bag dust collector is higher than that of electric precipitator, and the mercury removal efficiency of circulating fluidized bed boiler is higher than that of pulverized coal boiler. According to the research results, the recommended table for mercury removal efficiency of commonly used pollutant control devices in the design and calculation of coal-fired boilers is presented. In order to further guide the design and calculation of mercury removal from coal-fired boilers, the calculation formula of mercury removal efficiency of coal-fired boilers is studied in this paper, and six power plants are selected to analyze the mercury removal efficiency according to the mercury emission limit standard of China. The research shows that the existing pollutant units can basically ensure that the removal efficiency of mercury is controlled within the limits required by the Chinese national standards, and for coal-fired boilers with high mercury content in coal in the Yungui area of China, the removal efficiency of mercury can be controlled within the limits required by the Chinese national standards. When the mercury removal efficiency of the pollutant control unit reaches 90 ~ 95, the mercury emission value of most coal-fired boilers can be controlled to reach the national standard limit. Combined with the ideal gas theory, this paper also analyzes the actual influence of mercury on the flue gas volume of coal-fired boilers. It is concluded that the influence of mercury on the flue gas volume is very small and can be ignored.
【学位授予单位】：华北电力大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TK229.6

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