The nitrogen distribution in products during catalytic cracking of coker gas oil(CGO) was investigated in a laboratory two-staged riser catalytic cracking(TSRFCC) experimental unit with Kelamayi CGO as feedstock.The r...The nitrogen distribution in products during catalytic cracking of coker gas oil(CGO) was investigated in a laboratory two-staged riser catalytic cracking(TSRFCC) experimental unit with Kelamayi CGO as feedstock.The results showed that operation parameters,such as reaction temperature,catalyst-oil ratio and residence time,all could significantly affect the nitrogen distribution in the products.The nitrogen in the gas product and gasoline fractions decreased with the increase of reaction temperature and/or residence time,which could promote the thermal cracking.However,the nitrogen in gas product and gasoline fractions increased with the increase of catalyst-oil ratio,which could mainly enhance the catalytic cracking.On the whole,after CGO conversion,about 50% of the total nitrogen could produce nitrogen-containing coke over catalyst,and 20% of the total nitrogen remained in heavy oil,while only a little of the total nitrogen could be transfered into diesel,gasoline and gas products.展开更多
The roles of such classical hydrogen-donor solvents as tetralin,decahydronaphthalene,dihydrophenanthrene and dihydroanthracene in visbreaking of vacuum residue were examined.It revealed that the effect of the hydrogen...The roles of such classical hydrogen-donor solvents as tetralin,decahydronaphthalene,dihydrophenanthrene and dihydroanthracene in visbreaking of vacuum residue were examined.It revealed that the effect of the hydrogen-donor solvents could be ranked as dihydrophenanthrene≈dihydroanthracene> tetralin> dihydrophenanthrene and that the appropriate amount added was around 15%.Further studies showed that the coke formation can be greatly reduced by adding hydrogen-donor solvents,consequently the hydrogen-donor approach allowed the operation of visbreaking at higher severity.The effect of hydrogen could be negligible when the hydrogen pressure was lower than 2.5MPa.展开更多
文摘The nitrogen distribution in products during catalytic cracking of coker gas oil(CGO) was investigated in a laboratory two-staged riser catalytic cracking(TSRFCC) experimental unit with Kelamayi CGO as feedstock.The results showed that operation parameters,such as reaction temperature,catalyst-oil ratio and residence time,all could significantly affect the nitrogen distribution in the products.The nitrogen in the gas product and gasoline fractions decreased with the increase of reaction temperature and/or residence time,which could promote the thermal cracking.However,the nitrogen in gas product and gasoline fractions increased with the increase of catalyst-oil ratio,which could mainly enhance the catalytic cracking.On the whole,after CGO conversion,about 50% of the total nitrogen could produce nitrogen-containing coke over catalyst,and 20% of the total nitrogen remained in heavy oil,while only a little of the total nitrogen could be transfered into diesel,gasoline and gas products.
文摘The roles of such classical hydrogen-donor solvents as tetralin,decahydronaphthalene,dihydrophenanthrene and dihydroanthracene in visbreaking of vacuum residue were examined.It revealed that the effect of the hydrogen-donor solvents could be ranked as dihydrophenanthrene≈dihydroanthracene> tetralin> dihydrophenanthrene and that the appropriate amount added was around 15%.Further studies showed that the coke formation can be greatly reduced by adding hydrogen-donor solvents,consequently the hydrogen-donor approach allowed the operation of visbreaking at higher severity.The effect of hydrogen could be negligible when the hydrogen pressure was lower than 2.5MPa.
