Research On Enriched Pollutants In The Fly Ashes During Circulating Fluidized Bed Combustion

The power station, as one of important sources of air pollution, people pay great attention to its tremendous emissions of SO_x and NO_x from power plants, while the research on fine particle emission has not been further studied.However with the pollution becoming more and more serious more and more attention was paid to it. The harm of fine particles is not only its aggradation in the lung but also its enrichment of heavy metals and organic pollutants. The research on micromechanism of fine particles and pollutant enrichment regulation is the base of developing new pollutant control technique. Electric agglomeration is becoming a research hotspot as an effective way to control fine particle. Because of particularity of pulse power supply, it has not only good charging effect but also good decomposition effect of manifold pollutant.Firstly particle pollution actuality and electric agglomeration technique were concluded, the process and regulation of fly ash sampling were introduced.Then the particle size distributionl, pore structure and microstructure of samples were analyzed. The samples included fly ashes at different operating condition, fly ashes from refuse incineration power plant and medical waste incineration before and after pulse discharge, fly ashes of different size fraction. Fly ash formation mechanism, the reason of combustion condition impact on particle size distribution and pore structure, pore structure of different particle size and pulse discharge impact on pore structure were discussed.At the aspect of heavy metal pollution analysis, firstly the method of heavy metal distilling and analyzing were introduced briefly. The distribution of heavy metal at different combustion condition and enrichment in different particle size fly ash were analyzed, distribution of heavy metal that affected by different factors and the reason of enrichment were discussed.At the aspect of organic pollutants analysis, firstly the method of organic pollutant distilling and analyzing were introduced briefly. Then the distribution of different organic pollutant at different combustion condition, different rings of PAHs distribution regulation were analyzed comprehensively; the enrichment of PAHs in fly ashes of different particle size was discussed; pulse discharge influence on distribution of organic pollutant, pulse discharge influence on distribution of PAHs and dioxins were discussed amply.The transform of heavy metal with the change of temperature utilizing the software-FactSage was simulated; the power of free electron was calculated and the mechanism of organic pollutants decomposition by pulse discharge was analyzed.