The Study Of Biomass Coal Water Slurry

With oil and natural gas resources reduce dramatically, the development of newclean fuel of coal substitute for the oil has become a trend. In addition, thedevelopment and utilization of biomass energy has been recognized as the mosteffective mean to reduce carbon emissions. Water hyacinth, listed as one of theworld’s top ten harm grass, has also been pressing to be energy developed. Fujiananthracite is a kind of low volatile, high ignition point, poor combustion, low activityanthracite. When such a low quality coal is rationally and effectively used, economicdevelopment in Fujian and even economic development and environmentalprotection in China will get significance improved. Therefore, the biomass coalwater slurry(biomass-CWS) containing Fujian anthracite, water hyacinth anddispersant is developed, which is a substitute for heavy oil for combustion, not onlyimproving the burning anthracite of coal，but also reducing the amount of coal, andmaking full use of biomass resources.This article focuses on the study of biomass coal water slurry as follows:（1）The slurry ability of the biomass coal water slurry is studied with threeanthracite (Datian anthracite, Yongan anthracite, Longyan anthracite) and differentamount of dispersant. The results illustrated as following points: The biomass coal waterslurry made by3%～3.5%water hyacinth and1%dispersant could be produced atacceptable viscosity within0.8Pa·s～1.2Pa·s with excellent stability, meet the Chinesetechnical specification standards of coal water mixture (GB/T18855-2002). Consideredfrom slurry ability effect, the way to make Biomass-CWS was feasible. And the viscosity ofbiomass coal water slurry increases while biomass content is increased. The viscosity ofbiomass coal water slurry become lower as the mixing intensity increases. As thetemperature is under60℃, the viscosity of biomass coal water slurry declines withtemperature increases. Above60℃the viscosity increases with temperature increases.(2)The atomization characteristics of CWS and Biomass CWS are stuied. Theresults show that both CWS and Biomass-CWS atomized particle size smaller than26μm are accounted for90%, so the biomass addition has not greater impact on thequality of atomization. And with the biomass concentration increases, atomizedparticle size (Sauter mean diameter, SMD) increases, but the increase was modest; atomization SMD of biomass with coal has increased with the slurry apparentviscosity increases, but the increase is less than0.5μm..(3)The combustion characteristic of coal, CWS, Biomass-CWS, are studied bythermalgravity analysis with TG-DTG method. The results show that, thecomprehensive burining index(S) of Bimass-CWS is better than CWS, whichincreases with biomass content increase; the ignition temperature and burnouttemperature of Biomass-CWS are also lower than that of CWS, which decreases withthe increases of biomass content. The order of the apparent activation energy bykinetic analysis is: Longyan coal>Datian coal>Yongan coal>Datian biomass-CWS>Longyan biomass-CWS> Yongan biomass-CWS.