焦油渣性质评价与加氢裂化性能研究

焦油渣中挥发的有机烃类化合物易造成较为严重的环境问题,对焦油渣的较高处理成本导致其仍未能被有效处理与合理利用,因而有必要对焦油渣的性质和高附加值利用进行研究。对2种不同煤炭加工技术在生产中获得的焦油渣进行性质分析,并对焦油渣在高温高压下加氢裂化性能进行研究,即加氢裂化反应后得到的气体产物采用组分分析后得到气产率,对液固产物进行萃取分离后可得到不同条件下加氢裂化反应的氢耗、气产率、液相物产率和四氢呋喃不溶物的转化率。通过对不同加工途径所产生焦油渣的性质进行研究可发现,大多数焦油渣含有10%以上的水分和20%以上的焦油,焦化和气化工艺所产焦油渣中的灰分较高而中低温热解焦油渣的灰分相对较低,且其甲苯不溶物和四氢呋喃不溶物均高于中低温热解焦油渣。由2种典型焦油渣在不同的工艺条件、催化剂和供氢介质作用下加氢裂化的实验结果表明:通过改变工艺条件和催化剂,中低温热解焦油渣中95%以上的组分均能被裂解为轻质化合物,气化焦油渣中四氢呋喃可溶解的组分也能够进一步被裂解为轻质组分,而其固含物却难以再被进一步地裂解。

Study on the properties and hydrocracking performance of tar residue

The volatile organic hydrocarbons in tar residue are easy to cause serious environmental problems.The high cost of tar residue treatment leads to its not being effectively treated and rationally utilized.Therefore,it is necessary to study the properties and high added value utilization of tar residue.The properties of tar residue coming from two different coal processing were analyzed,and the hydrocracking performance of tar residue under high temperature and pressure was studied.The components of gas after hydrocracking reaction were analyzed by GC,and the liquid-solid products were separated by solvent extraction,so that the hydrogen consumption,gas yield,liquid yield and conversion rate of tetrahydrofuran insolubles of hydrocracking reaction under different conditions could be obtained.It is found that most of the tar residues contain more than 10%water and more than 20%tar.The ash content of the tar residue produced by coking and gasification process is higher than that of the medium-low temperature pyrolysis tar residue,and its toluene insoluble or tetrahydrofuran insoluble are higher than that of the medium-low temperature pyrolysis tar residue.From the results of hydrocracking of two typical tar residues under different process conditions,catalysts and hydrogen donor solvent,more than 95%of the components in the medium-low pyrolysis temperature tar residue can be cracked into light compounds by different conditions and catalysts.However,the soluble components of THF in gasified tar residues can be further cracked into light components,while the solid content is difficult to be further cracked.