掺混化工污泥对水煤浆成浆性能的影响研究

Effect of chemical sludge blending on the characteristics of coal water slurry

在水煤浆中加入一定比例的化工污泥,可有效利用污泥的热值以达到污泥资源化利用的目的,但仍存在化工污泥含水高且掺入过多会影响水煤浆成浆性能的问题,因而需对化工污泥进行机械改性实验。以神府东胜煤为原料,研究三峰级配工艺制备污泥水煤浆过程中机械改性化工污泥性质的变化及其掺混制浆的掺入方式和最大掺入量,通过对化工污泥的机械改性实验、改性污泥替代不同粒级原料制浆实验研究,借助旋转黏度计、激光粒度仪探讨了化工污泥机械改性及污泥水煤浆成浆过程中的作用机制。结果表明,针对化工污泥进行机械改性,其最佳改性条件为:原料与磨介之比为1∶3、搅拌速率35 Hz、改性时间25 min,制备出的改性污泥黏度最低、平均粒径最小;污泥掺混制备水煤浆,采用改性污泥替代细粒级煤时的成浆效果最佳;在不影响煤浆浓度的前提下,改性污泥最大掺入量可达1%(干基)。

Adding a certain proportion of chemical sludge to coal water slurry can effectively utilize the sludge calorific to achieve the goal of sludge resource utilization.However,there is still a problem of high water content and excessive addition of chemical sludge,which can affect the slurry performance of coal water slurry.Therefore,it is necessary to conduct mechanical modification experiments on chemical sludge.In this paper,taking Shenfu Dongsheng coal as raw material,the change of mechanical modification properties of chemical sludge,the mixing method and the maximum mixing amount of chemical sludge in the process of preparing sludge coal water slurry with three peak grading process were studied.Through the mechanical modification experiment of chemical sludge,the experiment design of replacing different particle size raw materials with modified sludge,the mechanism of chemical sludge mechanical modification and CWS slurrying process was discussed by laser particle size analyzer.The results show that when the chemical sludge was mechanically modified under the following conditions:the raw material and grinding medium ratio is 1∶3,stirring rate is 35 Hz,the modification time is 25 min,the prepared modified sludge has the lowest viscosity and the smallest average particle size;the best slurry formation effect is achieved when modified sludge is used to replace fine-grained coal in the preparation of coal water slurry by mixing sludge;on the premise of not affecting the concentration of coal slurry,the maximum addition amount of modified sludge can reach 1%(dry basis).