ZHANG Yunlei;SUN Zhongchao;LIANG Daming;XIONG Yinwu;LI Yanfang;Coal Chemistry Branch of China Coal Research Institute;Beijing Key Laboratory of Coal Based Carbon Materials;State Key Laboratory of High Efficient Mining and Clean Utilization of Coal Resources;Activated coke dry method flue gas purification technology has the advantages of low water consumption,no secondary pollution and recyclable use of adsorbent,and has broad development prospect.As the core of the process,the research of reactor has become the key to restrict the development of this technology.The flue gas emission characteristics and the pollutant emission limits of different industries are different.Accurately selecting the reactor type and optimizing the reactor structure according to the flue gas characteristics is an effective means to improve the system flue gas purification efficiency.In this paper,the advantages and disadvantages of various types of reactors currently used in the field of activated coke flue gas purification and its scope of application were introduced,the effects of different types of internal components on the gas-solid two-phase motion state in the reactor were discussed,and the future research direction of activated coke and the optimization of flue gas purification reactor were finally proposed.In terms of reactor bed type,the technical advantages and shortcomings of three types of reactors,including fixed bed reactors,moving bed reactors and fluidized bed reactors,were summarized.Among them,the structure of fixed-bed reactor is simple and usually used in the active coke desulfurization process. When the flue gas treatment volume is small,the flexibility is strong.As the flue gas treatment volume increases,its purification effect decreases and multiple reactors are required to operate in parallel,which has large area,high input cost; fluidized bed reactor has the advantages of large gas-solid flux,high automation,excellent mass and heat transfer performance,but it is not suitable for granular active coke due to strong internal particle wear,and has good applicability for powdery activity coke; the moving bed reactor is currently the most widely used in the field of active coke flue gas purification,with the advantages of strong continuity,large flue gas treatment capacity,and low requirements for particle mechanical strength,but its internal structure is complex,and materials are prone to abnormal flow.With regard to the internal components of the reactor,the effects of flue gas guide components,ammonia injection mixing components,and discharge components on the system's flue gas purification efficiency were discussed.In view of the turbulent gas flow in the reactor,the uniformity of flue gas in the reactor can be improved by adding a deflector or a rectifying layer; in order to improve the uniformity of ammonia injection,ammonia injection components can be provided in the ammonia injection area to improve the denitrification efficiency of the system,the more common ammonia injection components include static mixers,ammonia injection grids,and vortex components.Among them,static mixer is precisely controlled,but the cost is high and the processing capacity is limited.The ammonia injection grid can achieve zone control but is easy to appear the problem of pipeline clogging.The cost of vortex component reconstruction is low,but the control flexibility is poor.In industrial production,it is necessary to flexibly select ammonia injection components according to the amount of ammonia injection and flue gas emission indicators; in order to prevent solid materials from appearing " funnel flow" and other abnormal flows during the movement of the reactor,a discharge member can be added inside the reactor,which can effectively improve the flow state of solid materials in the reactor.After adding internal components,the gas-solid contact in the reactor is enhanced,the system purification efficiency is significantly improved,and the cost of transformation is reduced.Finally,it was clarified that the future activated coke flue gas purification reactor will be developed in the direction of innovative reactor bed type,enhancing industry matching,optimizing reactor structure,and reducing operation and maintenance costs.
2020 04 v.26;No.128 [Abstract][OnlineView][HTML全文][Download 6625K]