Compressor Design and Selection

You've said: Since the amount of flash gases has increased from 1 MMScfd to 4.3 MMscfd therefore, we have to install another compressor in parallel with existing one (Max Capacity = 1 MMScfd) to cope the increased flow of flash gases. Furthermore we want a rental compressor.

It seems your decision causes un-uniformity in process system. I think it's better and more efficient that you perform an Economic/ Technical evaluation about the Compression of TOTAL Flash Gas to get the optimum & uniform design before doing any decision about the increase the no. of compressors with different capacity from old one.

In the light of above discussion I need comments for compressor designers and suppliers that what steps and procedures shall I take. What data/calculations will I have to be shared with designers/suppliers.

Required information for the vendor: You as client ( or your designer, consultant) have to prepare : Data Sheet mostly contained process information, the probable standard views as supplement to the standard accepted by vendor, P&ID( if required).