石子煤气力输送系统阻力特性研究

Investigation on resistance characteristics of pneumatic conveying system for pebble coals

通过搭建石子煤气力输送系统中试试验台,研究了纯通风条件下,输送系统管路上的静压和气流速度分布特征,得到了纯通风条件下输送系统的沿程阻力系数和局部阻力系数;进一步探讨了筛分后不同粒径石子煤颗粒的沿程阻力和局部阻力特性,并对未经筛分的石子煤原料进行了阻力特性研究。结果表明:该系统可成功输送电厂磨煤机排放的石子煤颗粒;随石子煤粒径增大,沿程阻力系数和局部阻力系数有所增加;随石子煤质量浓度增加,各粒径石子煤的沿程阻力系数和局部阻力系数均呈上升趋势;混合粒径石子煤颗粒的斜坡段阻力系数稍高于直管段摩擦阻力系数,局部阻力系数则远高于前二者。

Several researches have been made about pneumatic conveying of pebble coal on an experimental pilot platform. Firstly, the static pressure and velocity distributions along the pipeline of airflow without carrying pebble coal were studied; the flow resistance and local resistance coefficients of airflow were then obtained. Secondly, one group of pebble coal samples were sieved into different particle sizes, then the flow resistance and local resistance characteristics of pneumatic conveying of pebble coals with different particle sizes were researched. Lastly, the other group of pebble coal samples which are unsieved ones were tested for comparison. Results show that pebble coal which is produced from mills in power plants can be successfully conveyed by the designed system. As the increasing of pebble coal sizes, the flow resistance and local resistance coefficients increased; as the increasing of pebble coal concentration in airflow, the flow resistance and local resistance coefficients of pebble coals with different particle sizes show an increasing trend. Pneumatically conveyed in an ascending slope pipe, the flow resistance coefficient of pebble coals is a little higher than in a horizontal pipe, while the local resistance coefficient is much larger than the two former.