鸡粪和农林生物质混燃发电的探索

Exploration of Power Generation by Mixed Fuel of Chicken Manure and Agricultural and Forestry Biomass

为克服鸡粪燃料的限制问题,从燃料收储与加工、锅炉技术改造及运行管理优化等方面,对鸡粪与农作物秸秆、稻壳及林木废弃物混合燃料在高温超高压30MW生物质直燃发电机组中的应用进行探索研究。针对混合燃料入炉质量与给料量不稳定的问题,改进混合燃料制备方案,优化燃料给料机结构和输送系统运行频率。通过热力学计算分析,增大锅炉水冷壁蒸发受热面积,从而提高锅炉出力。根据积灰形成机理,重点改造锅炉吹灰方式、重新布置吹灰器,以消除高、中温过热器处的严重积灰和结渣现象。把锅炉部分烟冷器更换为光管式管束,使烟冷器积灰堵塞现象得到解决。由此,基本消除了设备长周期运行的制约因素。同时根据不同的燃料结构,形成多套有针对性的入炉燃料掺配与运行参数调整方案,锅炉运行调整及各参数控制达到优化组合状态。经过一系列技术改造与运行优化调整,在机组负荷率99%以上的工况下,单炉膛120t/h高温超高压循环流化床锅炉实现了持续96天的稳定运行。

In order to overcome the limitation of chicken manure fuel,the application of the mixed fuel of chicken manure and crop straw,rice husk and forest waste in high temperature and ultra-high pressure 30MW biomass direct-fired generator set was explored from the aspects of fuel collection,storage and processing and the technical transformation and operation management optimization of boiler.In view of the unsta-ble incoming quality and feed amount of mixed fuel in the furnace,the preparation scheme of mixed fuel was improved,and the structure of fuel feeder and the operation frequency of conveying system were optimized.Through thermodynamic calculation and analysis,the evaporative heating area of boiler water wall was increased to improve the boiler output.According to the mechanism of soot formation,the soot-blowing mode for boiler was revamped and the soot blowers were rearranged to eliminate the serious soot formation and slagging at high-temperature and medium-temperature superheaters.Part of the flue gas coolers in boiler were replaced with light tube bundle,so that the soot formation and blockage of flue gas cooler can be solved.Thus,the factors restricting the long-term operation of equipment were basically eliminated.At the same time,a number of targeted fuel mixing and operating parameter adjustment schemes were formed according to different fuel structures,and the boiler operation adjustment and parameter control achieved an optimal combination.After a series of technical transformation and operation optimization and adjustment,the 120t/h high temperature ultra-high pressure circulating fluidized bed boiler in a single furnace achieved stable operation for96 consecutive days at a unit load rate of above 99%.