Q. Design Gas Compressors?

As gas compressors are often high investment equipment, it makes sense to locate these well away from other equipment to minimize potential fire damage. Where there are several large compressors in a process unit, it is usually economical for operation and maintenance to locate them in one area. Associated intercoolers, knockout drums, etc. may be located in the compressor area and need not comply with the minimum spacing to non-associated equipment, provided that they do not restrict access for firefighting and maintenance (generally, spacing of 3 to 4.5 m (10 to15 ft.) is sufficient).

Access for firefighting must be available on at least two sides. Compressor orientation should consider the possibility of massive mechanical failure in relation to surrounding equipment. Compressors handling inert gases or air may be spaced closer than is shown for gas compressors,
unless they are in a service critical to plant operations such as main plant instrument and industrial air systems.

Small steam or electric motor driven compressors (< 150 kW (200 hp)) may be treated as pumps for spacing and location purposes. Compressors and associated equipment should be located to minimize pressure drop in suction pipe work.

Compressors driven by condensing steam turbines need to be elevated to fit the condenser below the turbine. In this case an elevated platform will be necessary with stair access and a secondary means of escape. The lube and seal oil units are often packaged modules and space needs to be allocated below the compressor for gravity flow of oil return lines. Space for local control panels must also be allowed for, adjacent to the machine.

For weather protection and noise reduction purposes, compressors should normally be located in an enclosed or semi-enclosed building or shelter. Foundations for large compressors should be isolated from building foundations, and separate compressor trains should also have independent foundations.