Biogas compressor Biogas compressor David Medina (Mechanical) (OP) 23 Jun 17 16:12 Hello. What is the approximate price of the biogas compressors? The necesity is that the biogas compressure at 5 bar. And the other at 18.5 bar. RE: Biogas compressor pmover (Mechanical) 23 Jun 17 16:44 Before obtaining cost data, first and foremost, the process conditions (i.e. inlet/outlet P&T, gas composition, and flow rate(s) ) needs to be defined. flow rate and compression pressure ratio will largely dictate the type of compressor. What is the application? The main types of compressors are centrifugal & reciprocating; each with appropriate uses/fit. I suggest a review of the GPSA Databook section on Compressors for further information/aid. good luck! -pmover RE: Biogas compressor zdas04 (Mechanical) 23 Jun 17 19:36 pmover, You would be more accurate if you said the two types of compressors are "rotary and reciprocating" or "dynamic and positive displacement". The "rotary" category would include centrifugals, but it also includes axial compressors, dry screw compressors, oil flooded screw compressors, liquid ring, etc. The "dynamic" category includes centrifugals, but it also includes axial and various fans. Saying "centrifugal and reciprocating" is kind of confusing. But your basic point is spot on--any number provided for a "cost of compression" with the original information provided would be meaningless and hugely misleading. If we make the assumption that the only two numbers provided are suction pressure and discharge pressure (although it is unclear how the biological process pressured the gas up to 5 bar on the suction side of the compressor), then it is still impossible to quote a compressor without knowing a flow rate. It could be small enough to run of wall power or big enough to require a dedicated driver (i.e., hundreds of dollars to millions of dollars for the same suction/discharge pressure pair). David Simpson, PE MuleShoe Engineering In questions of science, the authority of a thousand is not worth the humble reasoning of a single individual. Galileo Galilei, Italian Physicist RE: Biogas compressor BigInch (Petroleum) 23 Jun 17 21:10 I see "compressors" to mean he needs 2 compressors, most likely one discharging at 5barg the other at 18.5barg. Richard Feynman's Problem Solving Algorithm 1. Write down the problem. 2. Think very hard. 3. Write down the answer.