木钠添加剂对水煤浆流变行为的影响研究

INFLUENCE OF ADDING THE SODIUM LIGNOSULFONATE SURFACTANT ON THE RHEOLOGICAL BEHAVIOR OF COAL-WATER SUSPENSIONS

研究了木质素磺酸钠(简称木钠)对水煤浆流变行为的影响,包括木钠的浓度和分子量、浆体温度、p H值及木钠与NDF在预剪切条件下的流变性能.结果表明:木钠的添加量超过煤重的0 .8%时,煤浆表观黏度随添加剂的增加而增加.不同分子量的木钠对煤浆的流动性会有不同的影响.分子量在1 0 0 0 0～5 0 0 0 0级分对流变性较为有利.煤浆的温度低于60℃时,煤浆的黏度会不断减少;超过60℃时,黏度会有增加.煤浆溶液在弱酸和弱碱条件下,p H值为9时可使黏度较低.木钠在上述不同的条件下均有较为理想的假塑性.在预剪切实验中,随着预剪切时间的增加煤浆黏度会不断增加.

The influences of adding the sodium lignosulfonate (LS) on the rheological characteristics of coal-water suspension were investigated,including the effects of LS concentration,different molecular mass,suspension temperature,suspension pH and the rheological characteristics comparison of LS and NDF.The excessive surfactant can induce the apparent viscosity to increase if the dosage is more than 0 8% by coal weight.Different molecular masses of LS have different influences on the suspension fluidity.The fraction of 10 000-50 000 is a good choice for the fluidity.The suspension apparent viscosity decreases as the temperature is less than 60 ℃.The temperature exceeds 60 ℃,the viscosity will increase.Considering the fluidity,the appropriate pH is about 9 in the range of weak acid and basic in the suspension. LS has an ideal pseudoplasticity in above different conditions.The preashearing experiment reveals that the suspension viscosity added the LS surfactant increases with the time prolonging.