| 摘要 |
The invention concerns an FCC pretreatment method by soft hydrocracking of a hydrocarbon feedstock comprising a distillate fraction under vacuum or a deasphalted oil or a mixture of those two fractions, called main feedstock, to produce diesel oil and an effluent having an initial boiling point higher than 320 °C, said effluent (FCC feedstock) being then subjected to a catalytic cracking; method whereby at least 85 wt. % of said main feedstock boils above 375 °C and at least 95 wt. % of said main feedstock boils below 650 °C, the soft hydrocracking being carried out under an absolute pressure of 2 to 12 MPa's and at a temperature ranging between 300 and 500 °C. Said method is characterized in that the hydrocarbon feedstock further comprises a lighter hydrocarbon fraction, called secondary feedstock, whereof at least 50 wt. % boils below 375 °C and at least 80 wt. % boils above 200 °C. |
