Abstract:

This paper takes a new petrochemical project as an example to discuss two schemes for the membrane separation of slurry bed residue hydrocracking unit, providing reference for the selection of membrane separation scheme for high-pressure hydrocracking unit in the future. In Scheme A, the primary permeable gas, with a pressure of 5.50 MPaG, is sent to the first stage inlet of make-up hydrogen compressor, and the secondary permeable gas, with a pressure of 2.80 MPaG, is sent to the downstream PSA unit. In Scheme B, the primary permeable gas, with a pressure of 9.50 MPaG, is sent to the second stage inlet of the make-up hydrogen compressor, and the secondary permeable gas, with a pressure of 2.80 MPaG, is sent to the downstream PSA unit. Compared with Scheme A, Scheme B recovers pressure energy and reduces energy consumption, but has higher investment cost. While maintaining a high purity and recovery rate of primary permeable gas hydrogen, the technology with lower primary permeable gas pressure has lower technical barriers, and most of the domestic membrane separation technology can meet the requirements.

Key words: membrane separation, high-pressure hydrogenation, permeable gas, slurry bed