摘要
在输送压力可达4.0MPa的气力输送试验台上进行两种煤粉不同外水含量下的密相输送试验,研究煤粉表面性质和外水含量对流动特性的影响。结果表明:相同外水含量下,年轻煤流动性较好;中等变质煤在初始外水含量(外水M=0.40%)下存在显著的静电效应,外水含量增加,静电效应明显抑制;随着外水含量增大,中等变质煤的质量流量和固气比先略增大后逐渐减小,年轻煤则呈逐渐减小趋势;弯管当量长度系数K与输送气速近似成比例关系,相同气速下年轻煤K值逐渐增加而中等变质煤则先略有减小后急剧增大。通过试验,获得了两种煤粉高压密相输送外水含量的极限值。
Dense-phase pneumatic conveying experiments of two kinds of pulverized coal with various external moisture contents were carried out at the experimental facility with conveying pressure up to 4.0 MPa.The influences of external moisture content and surface characteristic on flow behavior were investigated.The results show that flowability of low rank coal is better than that of medium rank coal under the same external moisture content.Medium rank coal with initial moisture content（M = 0.40% ） exhibits significant electrostatic effect while being transported,and the electrostatic effect is weakened while the external moisture is increased.Mass flow rate and solid loading ratio of medium rank coal increase at first and then decrease while those of low rank coal decrease with the increase in external moisture content.Bend equivalent length K is approximately proportional to conveying gas velocity under the same external moisture content.For the same gas superficial velocity,bend equivalent length K of low rank coal rises with increase in moisture content and that of medium rank coal drops slightly at first and then increases sharply.Limit values of external moisture content for two kinds of pulverized coal were obtained by conveying experiments.
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2010年第8期1359-1363,共5页
Journal of China Coal Society
基金
国家重点基础研究发展计划(973)资助项目(2010CB227002)
国家自然科学基金资助项目(50906011)
关键词
外水含量
高压
气力输送
压损
弯管当量长度系数
external moisture content
high pressure
pneumatic conveying
pressure drop
bend equivalent length
