Study On Slurryability Of Coal Slurry Based On Coal Blending And Adding Second Liquid

The slurry formation characteristic of gasification raw materials is one of the key control indexes of coal water slurry gasification,which directly affects the long-term safe and stable operation of the gasification plant.With the increase of carbon emission reduction and speed up,gasification raw materials continue to expand,and higher requirements are also put forward for the study of slurryability of materials.Hydrocarbon-containing solid raw materials such as low-rank coal,semi-coke and petroleum coke have been used as entrained-flow gasification raw materials.In order to improve the slurryability of low-rank coal,semi-coke and petroleum coke and explore the slurryability law of oil-coal water slurry,the effect mechanism of coal blending and the addition of second liquid on the preparation of coal slurry was studied in this paper.the effect of kerosene surface modified mixed particles on the slurryability of coal slurry and the slurryability of oil-water mixture prepared by diesel oil and water were discussed,and the application of plant ash in the preparation of coal-water slurry was also discussed.It has important reference significance for regulating the slurryability of multi-component coal slurry.The main results are as follows:(1)The study on the slurryability of petroleum coke,semi-coke and low-rank coal blending combined with the surface modification of second liquid kerosene shows that the addition of petroleum coke and semi-coke can increase the slurry concentration of low-rank coal,when the coke content accounts for 25.0%of the solid mass,the slurry concentration of coal coke slurry from petroleum coke increased from 58.0%to 62.0%,and the slurry concentration of coal coke slurry from semi-coke increased from 61.0%to 62.0%.The addition of kerosene surface modified mixed particles can enhance the hydrophobicity of particles and further increase the concentration of coal coke slurry.When α=25.0%and kerosene accounts for 0.5%of the solid mass,the slurry concentration of petroleum coke slurry increases from 62.0%to 63.4%.The slurry concentration of Semi-coke slurry increased from 62.0%to 65.0%.(2)The study on the slurryability of oil-coal water slurry of low-rank coal,semi-coke and petroleum coke mixed with second liquid diesel oil and water shows that when low-rank coal,semi-coke and petroleum coke form normal slurry,the proportion of diesel to liquid phase is 0.0～50.0%,0.0-50.0%and 75.0～100.0%,respectively.Beyond this range,flocculent agglomeration will occur,and the maximum slurry concentration of oil-coal water slurry decreases with the increase of diesel addition.When ε＝50.0%,the maximum slurry concentration of oil-coal water slurry decreases with the increase of diesel content.The maximum slurry concentration of N changed from 59.0%to 43.0%.The maximum slurry concentration of L changed from 66.0%to 50.0%.When ε=75.0%,the maximum slurry concentration of Z changed from 70.0%to 63.0%.The viscosity of oil-coal water slurry decreases with the increase of temperature.when ε=50%and the temperature is 65℃ the viscosity of N,L and Z decreases by 32.0%,32.5%and 39.0%,respectively.(3)The study on the slurry ability of plant ash and petroleum coke blended coal to make petroleum coke water coke slurry shows that the addition of plant ash can make the viscosity of petroleum coke water coke slurry fluctuate at first(ω<10.0%)and then increase(10.0<ω<15.0.%),and enhance its stability.When the concentration of water coke slurry is 70%,plant ash accounts for 15.0%of petroleum coke mass co,its viscosity increases 850mPa·s.The K+and Ca2+in the extract of plant ash are beneficial to enhance the stability and fluidity of water coke slurry,and have a good viscosity reducing effect on low-grade coal-water slurry.When the addition of K+is 1.0%,the viscosity of Yunnan lignite,Xinjiang raw coal,semi-coke and petroleum coking coal slurry decreases by 400,279,57 and 43 mPa·s respectively under the corresponding highest slurry concentration;when the addition amount of Ca2+is 1.0%,the viscosity is reduced by 185,180,21 and 11 mPa·s respectively.The insoluble matter in plant ash determines the change trend of viscosity and stability of water coke slurry with the addition of plant ash,but the range of change decreases.