我国中煤再选研究现状与可行性分析

Present Status and Feasibility Analysis on Middlings Rewashed in China

为研究邢台矿选煤厂中煤再选的可行性,总结分析了目前我国中煤再选的2种技术方案,即中煤破碎到粒度小于1(3或6)mm再选和中煤破碎磨细到粒度小于0.5 mm时再选,可根据中煤中可燃体与非可燃体嵌部状态确定中煤再选方案。在此基础上,对邢台矿选煤厂中煤进行了筛分、浮沉试验和破碎后3~0.5 mm粒级的浮沉试验。结果表明:邢台矿选煤厂现有的重介处理系统分选效果较好,中煤带煤量低,但中煤经过破碎解离后能释放出部分精煤。经初步预测,单台重介处理系统理论上每小时可从经过破碎的中煤里回收0.9 t精煤,每年多回收精煤约4 500 t,经济效益显著。

In order to study the feasibility of middlings rewashed from Xingtai Mine Coal Preparation Plant,the paper summarized and analyzed the present two middlings rewashed plans,including the particle size of middlings were crushed to 1( 3 or 6) mm and the particle size of middlings were crushed and grinded to 0. 5 mm.According to the embedded state of combustible and non-combustible in coal,it could determine the rewashed plan.On the basis of analysis,screening test and sedimentation test of middlings and particle size 3~0. 5 mm materials of crushed middlings were carried out.The results showed that the present dense medium separation system of Xingtai Mine Coal Preparation had good separation effects,the amount of gangue in middlings was low,but some clean coal could be achieved when middlings were crushed and dissociated.The initial prediction showed that 0. 9 t clean coal theoretically could be achieved from crushed and rewashed middlings to single handling capacity system per hour and more than 4 500 t clean coal could be obtained per year.