Industrial application of recovery technology for effective components in off-gas from butanol-octanol unit

Objective A process technology is developed to recover the effective components in off-gas from the reactive system of hydroformylation of propylene.

Methods This technology uses the process route of "dealdehyde-cryogenic separation-stabilization-distillation", i.e., firstly removing the heavy components such as butyraldehyde by distillation column and condensing the components above C₃ into liquid by ammonia circulating cryogenic process, and then removing butyraldehyde, trace moisture and non-condensable gas by the stable system, and finally obtaining propylene and propane products by distillation process.

Results After the commercial application of this technology, the design capacity of the off-gas effective components recovery unit is 17.72×10³ t/a. The total recovery of propylene, propane and butyraldehyde is 14.28×10³ t/a on the basis of operation time of 8 400 hours per year, and their purities are all greater than or equal to 97.00 wt%, their yields all exceed 95.0%.

Conclusions The actual values are better than the design ones after calibration. Compared with other units, this unit has the advantages of low energy consumption, no auxiliary material consumption, high yield and purity of products.