Rotary vane biogas compressors RF/RFL series

Sliding vane rotary compressors for biogas and natural gas

The MAPRO® sliding vane rotary compressors are used for compression of combustible gases, such as biological or natural gas, have been designed in order to fall within the Equipment- Group II as defined by the 2014/34/EU Directive, Category 2 both for the surrounding area conditions and for the internals of the machines.

• Pressure up to 3.2 bar (g)
• Flowrate up to 3,000 m³/h

Operating principle

A cylindrical rotor turns eccentrically in a cylindrical stator of a larger diameter: the free space left between stator and rotor is half-moon shaped. Some slots are milled in the rotor and stratified plastic blades slide freely into the slots. The blades, as the rotor turns, are forced out against the cylindrical wall of the stator by centrifugal force, so creating individual cells whose volume reduces from a maximum to a minimum during the rotation. The suction takes place through ports in the stator in the area of increasing volumes; the discharge through ports in the stator in the area of decreasing volumes.

Main construction features:

• Casing (stator and heads) in cast iron, rotor in carbon steel, blades in light stratified spark-free material
• Sealing between stator, heads and covers by gaskets and/or O-rings
• Simple or double mechanical seal, depending on the operating discharge pressure; for the double mechanical seal, the compressor-own oil lubricating system is used as a barrier fluid
• Flexible coupling, without metal-to-metal contact between driving and driven parts in case of failure of the coupling pins
• Safety drive guard made from spark-proof metal
• Type of protection “d” flameproof electric motors, with specific marking Ex II 2 G, additional marking Ex-d IIB T3

The most common fields of application

• Biogas recirculation into anaerobic digesters for sludge mixing
• Extraction of biogas from gasometer, landfill or other and delivery to storage systems or gas engine supply
• Extraction of natural gas from pipeline or gasometer, and delivery to storage systems or gas engine supply

Typical supply components

MAPRO® compressors for biogas or natural gas are normally equipped according to the use they are designed for.
The typical components for the most common applications, namely for the compressors designed for biogas recirculation into anaerobic digesters for sludge mixing and for the supply to gas engines, are listed on the schematic Piping and Instrumentation Diagrams(P&ID).

Complete Packages

These are complete ready to work packages including all components like:

• Oil separator
• Oil tank
• Pressure relief valve
• Flow regulation valve
• Non return valve
• Instrumentation monitoring pressure and temperature
• Safety ATEX devices like pressure switch, temperature switch
• Cooler
• Automatic condensate drain systems
• Pneumatically operated or motorized valves for the unloaded compressor starting
• Closed circuit cooling systems for the cooling water, complete with water pump, surge tank, air-water heat exchanger and all related control and safety devices
• Local control panels including relevant PLC

Typical P&ID diagrams are shown in below examples:

Brand