煤粉密相气力输送过程的水分含量影响研究

The effects research of moisture content on dense-phase pneumatic conveying of pulverized coal

以高水分含量的羊场湾煤粉为介质,以干燥空气为载气,在气力输送的自然干燥过程中考察了水分含量变化对粉煤密相气力输送特性的影响规律.实验结果表明,相比总水分含量,其外水含量是输送过程中更值得关注的参数.当总水分含量约11%、外水含量约5.8%时,羊场湾煤粉依然可以实现稳定的密相气力输送.外水含量的变化对输送性能包括如输送量、固气比、固相速度、稳定性等影响不大,这意味着其近6%的外水含量对颗粒间作用力影响较弱,尚不足以对其密相气力输送过程产生影响.

Taking high moisture content coal powder as a medium in Yangchangwan, using dry air as carrier, inspecting the influence law of pneumatic conveying characteristics of moisture content to dense phase change in natural drying process of conveying. The experimental results indicating that the surface moisture content is more dominant than the total moisture content. A stable dense-phase pneumatic conveying is still available for Yangchangwan pulverized coal in the condition of about total 11% and surface 5.8% moisture content. However, it has no obvious impact in conveying performance such as mass flow rate, solid-gas ratio, solid velocity and stability, when surface moisture content change, which implying that the interparticle force had no enough impact on its dense-phase pneumatic conveying at approximate 6% surface moisture content.