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Preliminary Study On Hydro-liquefaction Kinetics Of Shenhua Coal Macerals And Coliquefaction Of Macerals And Biomass

Posted on:2008-12-28Degree:MasterType:Thesis
Country:ChinaCandidate:J AiFull Text:PDF
GTID:2121360215493951Subject:Chemical processes
Abstract/Summary:PDF Full Text Request
Hydro-liquefaction of coal is necessarily choosen to reduce the supply pressure of oil .Our country has decided to build a hydro-liquefaction demonstration plant at Shendong coal field.At the late of the year 2004, the great project named basic research on massively direct hydro-liquefaction of coal,which would have been performed by China Coal Research Institute ,was carried out to support demonstration project and massive production.And one of key subjects from the project is hydro-liquefaction kinetics of coal.With developing the technology of hydro-liquefaction,our country need reasonabely make use of coal resource . And coliquefaction of coal and biomass waste is an exploration for decrease in the cost of coal liquefaction and promotion of effective utilization of biomass waste .Coal is the mixture consisted of some kinds of macerals .At the aspect of kinetics ,the research on hydro-liquefaction kinetics of macerals can help to understand the characteristic of coal in liquefaction and predict the distribution of products ;at the other aspect of coliquefaction of coal and biomass waste,the study on coliquefaction can offer basic theory and optimize its process operation to improve the conversion rate of coal and decrease the cost of coal liquefaction.Therefore,"preliminary study on hydro-liquefaction kinetics of Shenhua coal macerals and coliquefaction of macerals and biomass"is selected as the title in this paper.Rich macerals are hand picked from Shenhua coal to obtain samples .These samples are analyzed on petrography and coal property .And the experiments of kinetics and coliquefaction are carried out in a batch autoclave to study on kinetics laws and coliquefaction .Furthermore, residues of 0.01t/d continuous autoclave are analyzed and researched by means of microscopy to deeply understand the behaviour of macerals in liquefaction.Kinetics experimental results are showed as follows: the conversion constant rate of rich inertinite is 0.0097min-1at 450℃,the order of reaction conversion constant rate is asphaltene>oil> gaseous products.At 430℃and 460℃,rich vitrinite is divided into two fractions ,one is easily convertible,the other is unconvertible.The convertible one can form asphaltene,oil and gaseous products. And the unconvertible one can only firtly form asphaltene ,then can consecutively form oil and gaseous products .The activation energy of convertible one is 138.28KJ/mol,and the activation energy of unconvertible one is 159.78KJ/mol.Residues of 0.01t/d continuous autoclave are analyzed and researched by means of microscopy.Compared with raw coal ,residues of macerals show apparent changes.Liptinite is entirely converted .Mesophase and semicoke are formed. Vitrinite has changed greatly ,it forms vitroplast.It is investigated that the route for vitrinite : vitrinite is firstly converted to form vitroplast , then form liquid and gaseous products . Semicoke is from the conversion of inertinite.At 450℃, coliquefaction of coal and biamoss waste is investigated .As a result,under the same conditions the addition of sawdust to macerals can not enhance conversion and oil yield of coal.By contrast,it can apparently promote the asphaltene yield;the order of promotion value is rich vitrinite< rich inertinite.It is analyzed to inapparent promotion of coal conversion in coliquefaction.Pyrolysis experiments of macerals and sawdust are made .The results indicate that active pyrolysis temperature range of macerals and sawdust can not overlap ,it leads not to form synergetic function .Furthermore,the weight of solvent is not suitable ,it is also one of important influence factors.
Keywords/Search Tags:macerals, coliquefaction, kinetics, residues, pyrolysis
PDF Full Text Request
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