中国电机工程学报
中國電機工程學報
중국전궤공정학보
ZHONGGUO DIANJI GONGCHENG XUEBAO
2015年
17期
4417-4422
,共6页
么瑶%吕清刚%朱建国%欧阳子区%周祖旭
麽瑤%呂清剛%硃建國%歐暘子區%週祖旭
요요%려청강%주건국%구양자구%주조욱
细粉半焦%循环流化床%预热%燃烧
細粉半焦%循環流化床%預熱%燃燒
세분반초%순배류화상%예열%연소
fine char%circulating fluidized bed%preheat%combustion
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。
細粉半焦是低階煤熱解提質工藝的副產品,具有揮髮分含量低、著火點高、燃儘睏難等特點,實現細粉半焦的高效燃燒對低階煤的梯級利用有現實意義。文中利用燃料高溫預熱彊化燃燒的原理,提齣細粉半焦在循環流化床預熱燃燒的新工藝,在熱態試驗檯上,開展細粉半焦在無佈風闆結構、無預加惰性床料條件下循環流化床預熱過程的實驗研究,採用空氣輸送將細粉半焦直接加入沒有佈風闆的循環流化床中,在空氣噹量比為0.37的條件下對細粉半焦進行部分燃燒,利用細粉半焦部分燃燒的放熱預熱細粉半焦。研究結果錶明,循環流化床運行穩定,細粉半焦預熱溫度達到850℃,為後續的高效燃燒創造瞭良好的條件,由細粉半焦中的大顆粒在循環流化床中形成的高溫物料的循環是該新工藝的關鍵所在。
세분반초시저계매열해제질공예적부산품,구유휘발분함량저、착화점고、연진곤난등특점,실현세분반초적고효연소대저계매적제급이용유현실의의。문중이용연료고온예열강화연소적원리,제출세분반초재순배류화상예열연소적신공예,재열태시험태상,개전세분반초재무포풍판결구、무예가타성상료조건하순배류화상예열과정적실험연구,채용공기수송장세분반초직접가입몰유포풍판적순배류화상중,재공기당량비위0.37적조건하대세분반초진행부분연소,이용세분반초부분연소적방열예열세분반초。연구결과표명,순배류화상운행은정,세분반초예열온도체도850℃,위후속적고효연소창조료량호적조건,유세분반초중적대과립재순배류화상중형성적고온물료적순배시해신공예적관건소재。
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.