Experimental Analysis And Application Study On Catalytic Pyrolysis Of Yunnan Lignite In The Presence Of Ca Promoter

"Rich coal,lack of oil,less gas"is characteristic of our country,s energy,high-efficient and clean utilization of coal were written the country,s"13th Five-Year Plan".Coal catalytic pyrolysis technology has attracted more and more attention on home and abroad.Lignite which is from Yunnan province is abundant and contains a lot of volatile components.In this study,lignites were used as materials from different producing areas in Yunnan province,and analyzing in testing with catalytic pyrolysis by loading Ni,Ca,Ni-Ca,Fe and Fe-Ca catalysts.The main contents and results were as follows:?1?With the increase of temperature,gas and tar yields gone down firstlythen up.light oil yield increased at first then decrease,char yield was reduced,the tar yield was maximum of 21.30%and the gas yield was minimum of 4.42%at 600?.?2?Ni catalytic obviously increased the tar yiled,promoted the macro-molecular radicals and in the process of coal pyrolysis product of low molecular weight tar and car bocoal polycondensation reaction.SCX lignite catalytic pyrolysis total conversion yield was 51.62%?5%Ni?and the tar yield was 22.40%.GJS lignite catalytic pyrolysis total conversion was 49.06%?5%Ni?and the tar yiled was 23.16%.Ca significantly improved gas yiled and pyrolysis total conversion yiled,it promotd the coal pyrolysis process of macrom-olecular free radical into small molecules.The Ni-Ca catalyst obviously improved the gas yield of SCX lignite,and the tar yield reduced,and Promoted the transformation of radical fragments into small molecules in the process of coal pyrolysis and inhibited condensation polymerization in coal pyrolysis process.Ni-Ca catalyst maked a difference on the content of benzene,toluene,xylene,phenol,cresol and naphthalene?BXPCN?of GJS lignite pyrolysis was maximum of 6.62%When the load was 3%Ni;Ni-Ca load was 5%Ni+0.8%Ca up to 6.75%.?3?The tar yield was obviously reduced with Fe,inhibited the formation and condensation polymerization of free radicals in lignite.The gas and water yields were increased by promoting the transformation of molecular free radical fragminto small molecules in the process of coal pyrolysis.The total conversion yield of GJS lignite pyrolysis had reduced,however promoted the SCX lignite.The effect of Fe-Ca on the pyrolysis of SCX lignite was investigated on the basis of 5%Fe,Fe-Ca catalyst reduced the gas and tar yields.Promoted the transformation of molecular free radical fragminto small molecules in the process of SCX lignite but inhibited the GJS lignite pyrolysis.Ca₂Fe₂O₅ reduce the content of phenolic compounds in the pyrolysis tar of SCX lignite.Fe-Ca catalyst had a significant influence on the content of benzene,toluene,xylene,phenol,cresol and naphthalene in coal pyrolysis tar,which was selective to the distribution of its products.The total content of light aromatic hydrocarbon?BTXPCN?increased from 3.64%?raw coal?to 6.41%?5%Fe?,and the results showed that the Fe catalyst promoted the light quality of lignite pyrolysis tar.?4?Analyzing features of the results which catalytic pyrolysis products of SCX and GJS lignite in Yunnan province with the Ni-Ca and Fe-Ca.The results showed that Ni-Ca,Fe-Ca of lignite pyrolysis mechanism were different.The addition of Ca promoted the formation of xylene in the process of Ni catalytic pyrolysis.In the process of Fe catalyst,C_ar-C_ar,Ar-OH and C=O break bonds are promoted to realize the light weight of tar.