METHOD FOR OBTAINING OLEFIN C IN INSTALLATION FOR FLUID CATALYSTICAL CRACKING Russian patent published in 2016 - IPC C10G11/18 C07C11/06 C07C4/06 

FIELD: chemistry.

SUBSTANCE: method includes the following stages: (a) cracking of hydrocarbon raw material in riser, which works in temperature range from 500°C to 625°C in presence of fluidised solid microspheric cracking catalyst to obtain hydrocarbon products; (b) separation of coke-loaded waste catalyst from hydrocarbon products and its stripping in stripping column to remove hydrocarbons, trapped inside catalyst pores; (c) burning coke sediments on waste catalyst in regenerator; (d) recirculation of part of hot regenerated catalyst in stripping column with support of temperature in stripping column in the range from 550°C to 650°C and recirculation of remaining part of hot regenerated catalyst into lower part of riser; (e) pumping hydrocarbon fraction C₄, separated from cracking products, by selection with external stream of hydrocarbon C₄ into stripping column, with coke on circulating catalyst in stripping column constituting from 0.3 to 1 wt %, and WHSV value of WHSV being in the range from 5 to 50 hour^-1. Application of claimed invention increases activity of catalyst inside stripping column. Direct pumping of regenerated catalyst into stripping column in addition to increase of propylene output increases stripping efficiency, which leads to increase of extraction of hydrocarbons removed by stripping.

EFFECT: increase of propylene output in installation for fluid catalytic cracking.

7 cl, 1 dwg, 2 ex, 4 tbl