Effects Of Comb-like Polymer Additive On The Properties Of Coal-water Slurry

This paper,we synthesize two kinds of comb-type copolymers via side chain grafting: one series not containing MPEG side chain (SMANS); another series is SMANP containing different side chain length MPEG(Mw=350,750,1900g/mol) to study the effect of the coal-water slurry with different side chain length copolymer’s performance. We found that the two series comb-like copolymer additives can effectively reduce the viscosity of coal water slurry, the effect of SMANP 1 series was more obvious. At the same time, we found that the viscosity decrease with the increase of shear rate and temperature, CWS showed a typical pseudoplastic fluid behavior. By comparing the influence of the SMANP 1 series three comb-like copolymer on the viscosity added in coal water slurry, we found that the SMANP1 750 which had moderate molecular weight had the most outstanding performance. We found that SMANP1 series additives can effectively reduce the yield stress of CWS, and yield stress value gradually reduced with the increasement of polymer additives. We also found that CWS with SMANP1 750 had thixotropy and viscoelasticity. Finally we make the CWS with SMANP1 rheological curve fitting, and we found that coal-water slurry with SMANP1 series rheological curve basically corresponds to Herschel-Bulkley model. Through the coal-water contact Angle and Zeta potential of coal water slurry and SMANP1 in coal isothermal adsorption on the surface of the particles were systematic studied, then we found that different side chain length of SMANP1 series additives with the increase of equilibrium concentration, adsorption quantity increases gradually and finally constant, and this time reached maximum adsorption capacity. At the same concentration, the amount of 750 SMANP1 adsorption was the most, SMANP1 350, SMANP1 1900 adsorption amount reduced in turn. In practical applications, we cooperate with sinopec nanjing chemical industry company used one of our formula. Prepared of 5.8 tons of additives in their research institute,and successfully completed the project of increasing the coal-water slurry concentration.Turned the original device running coal-water slurry concentration from 60% to 62%. Provide the possibility to raw coal pulping process of nanjing chemical industry company in increasing productivity and efficiency.