Study on the Synthesis and Application of Polycarboxylic Acid CWM Additives
Coal Water Mixtures (CWMs) are densed suspensions of coal particles in water. Viscosity is one of the most important theological properties of CWMs and it is desired to be as low as possible. The slurry viscosity was influenced significantly by additive formation, the particle size distribution and the ash content of the coal. However, the influence of dispersants is most obvious. At present, there are several kinds of dispersants such as polymeric styrene sulfuric sodium, lignin sulfonate, humate, polycarboxy salt, ethylene epoxide surfactant.In this paper, a newly synthesized CWM dispersant has been reported, which is an efficient anionic surfactants of polycarboxylic acid type. The synthesis process includes three steps. At the beginning, the polyglycol acetate ester has been performed by acetic acid and polyethylene glycol (PEO) on the condition of acetic-acid/PEO ratio 1:1.1, at 368～373K for 30 minutes. Then the macro-monomer is prepared through the esterification of 85.71% acrylic and 14.29% polyglycol acetate ester, at 368～373K for 10 minutes. After that, the polycarboxylic acid CWM dispersant is polymerized using proper proportion macro-monomer, acrylic (AA)and sulfonic styrol sodium, at 368～373K for 1 hour.This new dispersants are used in the coal water mixtures formulation. Four kinds of coal used in the experiment are Shuang Yashan, Tunliu, Luning, Changcun samples.● The highest concentration for shuanyashan coal is 70% when the dosage of dispersant is 0.4%, and the content of -200 meshes particles is 75.53%. As the dosage of dispersant decreases to 0.25%, the Shangyashan CWM concentration is 67%.● For Tunliu coal CWM concentrations are in the range of 76% to 75% when dosage of the dispersant changes from 0.4% to 0.25% at the same particle size distribution of 83.5% minus 200 meshes.● The highest concentration for Luning coal is 69% when dosage of the dispersant is 0.4%,and the content of -200 meshes particles is 88.86%.● For Changcun sample, the coal concentration of CWM is 73%～75% when dosage range of the dispersant is 0.35%～0.5%.The experiments show that the synthesied dispersant is quite promising for some coals CWM preparation, but a little bit coal-dependent. The Proximate and Ultimate analysis, surface characteristic measurement have been made to investigate the interactions between coal and additives.
Synthesis Polycarboxylic acid CWM
S. Q. Zhu X. H. Wu Y. H. Mao L. M. Zhou W. W. Xie
School of Chemical and Environment Engineering, CUMTB, Beijing, China. School of Chemical and Environment Engineering,CUMTB, Beijing, China.
国际会议
XXIV International Mineral Processing Congress(第24届国际矿物加工大会)
北京
英文
3283-3290
2008-09-24（万方平台首次上网日期，不代表论文的发表时间）