盐水组分和碱性条件对水煤浆制浆的影响

Effect of Salt Solution and Alkali Solution on Preparation of CWS

通过选用不同浓度的NaCl、Na2SO4、Na2CO3、NaHCO3、CaSO4、MgSO4、NaOH溶液制备水煤浆,考察了不同制浆浓度下各添加物对水煤浆制浆特性的影响,添加组分对水煤浆pH值、燃烧热的影响。并测试了盐水与煤、碱水与煤的表面接触角。结果表明:盐水和碱水对水煤浆的黏度有较大影响。各盐水制浆的最佳盐水添加条件为1.0 wt% NaCl溶液,3.0 wt% Na2CO3溶液,0.50 wt% NaHCO3溶液,1.0 wt% MgSO4溶液。饱和CaSO4溶液和1 wt%浓度的NaOH溶液代替清水不利于成浆。Na2SO4的加入,不利于水煤浆的制备。各种盐水与碱水与煤的接触角都低于清水与煤的接触角。弱碱性条件有利于水煤浆黏度的降低,有利于制浆。浓度低于1 wt%盐水或碱水的加入不影响水煤浆的燃烧特性。

In this paper, through the use of different concentrations of NaCl, Na2SO4, Na2CO3, NaHCO3, CaSO4, MgSO4, NaOH solution for the preparation of coal water slurry, the effects of various additives of different pulp concentration on the pulping properties of coal water slurry, and the effects of composition of coal water slurry pH value, heat of combustion were investigated. And the surface contact angle between salt water and coal, alkali water and coal was tested. The results show that the salt water and alkaline water have influences on viscosity of coal water slurry. The best adding composition for salt water is 1.0 wt% NaCl, 3.0 wt% Na2CO3, 0.50 wt% NaHCO3, and 1.0 wt% MgSO4. Saturated CaSO4 solution and 1 wt% NaOH solution instead of water are not suitable for CWS preparation. The addition of Na2SO4 is not conducive to the preparation of coal water slurry. The contact angles of all the salts and alkali water showed a decreasing tendency compared with the contact angle of fresh water. Weak alkaline conditions are conducive to the lower viscosity of coal-water slurry and are useful for slurry preparation. Addition of less than 1 wt% saline or alkaline water does not affect the combustion characteristics of CWS.