双峰级配制备高浓度水焦浆的实验研究

Experimental study on preparation of high concentration semi-coke water slurry based on bimodal gradation

水焦浆是以半焦粉为原料的新型清洁高效液体燃料,通过破碎磨矿和不同物料粒度配比得到合理的粒度分布,是提高水焦浆浓度的重要措施。采用控制棒磨机磨矿时间的方法,对陕北柠条塔半焦样品平均粒径进行调控,制备出2种不同粒径半焦颗粒并探究了颗粒不同配比条件对水焦浆成浆特性的影响。使用Alfred粒度模型对物料配比进行计算拟合,发现当SZ(30±5μm小粒度物料)与CZ(120±10μm大粒径物料)的配比为3∶7和2∶8时具有较好的颗粒堆积效率。借助旋转粘度仪和Turbiscan Lab稳定性分析仪的多重光散射技术研究了不同配比对水煤浆浆体成浆性的影响,结果表明:当SZ与CZ的配比为3∶7时,浆体体系具有最优的成浆性,稳定性动力学指数TSI值较小,且无硬沉淀产生。通过对水焦浆不同制备因素的探讨,改善浆体流变性,最终得到最大固体浓度可达66.25wt%的高性能水焦浆。

Semi-coke water slurry is a new clean and efficient liquid fuel with semi-coke powder as raw material.Reasonable particle size distribution obtained by crushing and grinding at different material particle size ratios is an important measure to improve the concentration of slurry.In this study,two kinds of semi-coke particles with different sizes were prepared from Ning-tiao Tower semi-coke in northern Shaanxi by controlling the grinding time of rod mill.Different sizes of semi-coke particles were used to prepare semi-coke water slurry with double peak gradation,and the effects of different grain size gradation on slurry ability was explored.Based on the Alfred particle size model,it is found that when the ratio of SZ(30±5μm)to CZ(120±10μm)is 3∶7 and 2∶8,the system has a good packing efficiency of particles.The effects of different ratios on the slurry ability of semi-coke water slurry were studied by means of rotary viscometer and turboscan lab stability analyzer.The results show that:when the ratio of SZ to CZ is 3∶7,the slurry has the best slurry ability without hard precipitation produced.The rheological properties of the slurry were improved by exploring the different preparation factors of the semi-coke water slurry,and the high performance slurry with the maximum solid concentration of 66.25wt%obtained.