摘要
细粉半焦是低阶煤热解提质工艺的副产品,具有挥发分含量低、着火点高、燃尽困难等特点,实现细粉半焦的高效燃烧对低阶煤的梯级利用有现实意义。文中利用燃料高温预热强化燃烧的原理,提出细粉半焦在循环流化床预热燃烧的新工艺,在热态试验台上,开展细粉半焦在无布风板结构、无预加惰性床料条件下循环流化床预热过程的实验研究,采用空气输送将细粉半焦直接加入没有布风板的循环流化床中,在空气当量比为0.37的条件下对细粉半焦进行部分燃烧,利用细粉半焦部分燃烧的放热预热细粉半焦。研究结果表明,循环流化床运行稳定,细粉半焦预热温度达到850℃,为后续的高效燃烧创造了良好的条件,由细粉半焦中的大颗粒在循环流化床中形成的高温物料的循环是该新工艺的关键所在。
Fine char is the byproduct from low rank coal pyrolysis with the characteristics of almost no volatile, high ignition temperature, difficulty in burning-out. It is practically significant to realize high efficient combustion for the grading utilization of low rank coal. Based on theory of preheating strengthening combustion, a new technology for preheating fine char in a circulating fluidized bed （CFB） was proposed. On a pilot scale test rig, the preheating process of the fine char in a CFB was studied. In the experiment, the primary air was used to transport the fine char to the CFB without air distributor and bed material. The experimental results show that the fine char can be preheated to 850℃ and the CFB can be operated steadily and continuously in the air equivalence ratio of 0.37, which provides good condition for the following high efficient combustion. The circulation of high temperature fine char in the CFB is key to the self-sustaining preheating process.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2015年第17期4417-4422,共6页
Proceedings of the CSEE
基金
中国科学院战略先导科技专项(XDA07030100)~~
关键词
细粉半焦
循环流化床
预热
燃烧
fine char
circulating fluidized bed
preheat
combustion
