Study On The Preparation And Features Of Coal Pitch-alcohol-water Slurry

Coal pitch-alcohol-water slurry (CPAWS) is a similar-fluid fuel which mixed by coal tar pitch powder,alcohol materials,water and a small amount of additives.As a new type of fuel,it has advantages of low ignition point,high combustion efficiency,producing less ash and protecting environment.At first,the preparation technology of CPAWS has been researched in this paper.The experimental results indicated that the proportion of the materials had an important impact on slurry.After the research of fluid situation,appearance viscosity,stability and the pulping situation of CPAWS,simultaneously considered that the cost of slurry and the fuel calorific value,it has been considered when the coal tar pitch account for 50%,the ethyl alcohol account for 18%¹9%,the water account for 31%³2% in CPAWS,all aspects of slurry performance are the most appropriate;when the coal tar pitch account for 45%⁵0%,the methyl alcohol account for 20%²5%,the water account for 30% in CPMWS,all aspects of slurry performance are the most appropriate.One batch of feeding method in wet grinding had advantages of simple operation,more ideal grinding effects,good fluidity,and -200 mesh production rates can reach to 92.33%.The dispersant had the influential role to the wet grinding preparation of CPAWS,can reduce slurry viscosity and improved grinding efficiency.The equation of grinding kinetics for CTP,CPAWS and Coal pitch-methanol-water slurry (CPMWS) has been formulated respectively as following:R(t)=100exp[-(-0.11268+0.00132·d^1.09279)·t^{(1.85974-0.26352·lnd)}];R(t)=100exp[-(-1.3564+0.43454·lnd)·t^{(-0.42203+0.195241·lnd)}];R(t)=100exp[-(-0.02975+0.02908·d^0.67972)·t^{(-0.12083+0.13259·lnd)}]On the basis of slurry preparation research,the features of CPAWS have been also researched.The experimental results indicated that the change of materials proportion of CPAWS can change slurry rheological property,and change the slurry patter from a slight dilatant fluid,similar-Newtonian fluid to a yield pseudo-plastic fluid.The reasonable dispersant addition may reduce slurry apparent viscosity,change the fluid type of CPAWS,and improve the slurry fuel performance.The naphthalene sulfonate surface active agent has high dispersing performance to CPAWS,when the dosage of MC is 1%,slurry apparent viscosity is 85.5 mPa's and the fluidity is good.The combined dispersant can reduce the CPAWS apparent viscosity,enhance stability and control slurry cost,but the selected monomer dispersant's type matching and proportion must be appropriate,when the proportion of NDF and CLS combined dispersant is 5:5,the slurry apparent viscosity is 154.5 mPa's,it can be stably placed for three weeks,the fluidity and stability are comparatively ideal.The high polymer organic compounds can effectively improve the CPAWS stability,have solved the problem of slurry instability,CMC can improve the slurry stability most obviously;the slurry can be stably placed for four months.Compared to ordinary CWS fuel,CPAWS has lower ignition point,higher calorific value,better combustion,higher combustion efficiency,less burning ash,better environmental benefits.