1. Reaction Section
1) Catalyst counter-current flow optimizes the reaction conditions, which increases the yields of both liquid products and hydrogen. Compared with the co-current process, the yields of C5+ product and hydrogen can be approximately increased by 0.5%~1.0% and 5%~10% respectively.
2) Reactors are arranged side by side. The specification of four reactors are identical so that design, fabrication, install and maintenance are much easier than different specification reactors. Spare parts are universal for four reactors.
3) The average reaction pressure and the pressure of gas-liquid separator are kept at 0.35 MPag and 0.24 MPag, respectively.
2. Catalyst Circulation Section
1) The traditional method of increasing pressure by lock-hopper system has been abandoned. Catalyst is delivered from low pressure to high pressure by catalyst sealing legs. In this way, the catalyst transport system is simplified.
2) The process is simplified by the design of spend catalyst dust elutriation system due to dramatic decreases of catalyst attrition.
3) Spent catalyst is lifted by nitrogen while regenerated catalyst is lifted by hydrogen.
3. Catalyst Regeneration Section
1) The regenerator pressure is lower than that in the first reactor and higher than that in the last reactor, which is beneficial to both catalyst regeneration and catalyst transportation.
2) The burning zone consists of two moving beds. The bed temperature increases gradually so that temperature runaway can be avoided.
3) A cold loop process is introduced to the regeneration gas circulation.
4) A cooling zone is installed at the bottom of regenerator.