Type and size of the compressor depends on specific requirements of end application. Most important parameters for selection of compressor are pressure and capacity. For our skid based solutions we mainly use oil lubricated compressors to generate high quality compressed air, nitrogen or oxygen. In case of special requirements any other type of compressor (e.g. oil free, piston, high pressure ...) can be installed.

Downstream equipment can contribute to significant consumption of compressed air or generation of pressure drop and therefore it is recommended to select the compressor after downstream equipment is dimensioned and selected.

REMOVAL OF SOLID PARTICLES
After compression compressed air contains a lot of solid particles which were sucked in from the environment or generated as a result of corrosion/wear inside the system. For reliable operation of end application/process it is essential that concentration of solid particles is reduced down to the acceptable level.
Most basic typed of filters are:
- prefilter (3 μm),
- general purpose filter (1 μm),
- super fine coalescing filter (0,01 μm),
- activated carbon filter,
- sterile filter.

REMOVAL OF OIL
In case of oil lubricated compressors compressed air contains relatively high amount of oil (2,5 – 10 mg/Nm3).

Reduction of oil content can be achieved by:
- superfine coalescing filter (down to 0,01 mg/Nm3)
- activated carbon tower (down to class zero)

REMOVAL OF WATER
Reduction of water content is usually achieved with:
- refrigerant dryers (down to pressure dew point 3 °C).
- adsorption dryers (down to pressure dew point -70 °C).
- membrane dryers (down to pressure dew point -40 °C).

Nitrogen is an inert gas that is suitable for a wide range of applications, covering various aspects of chemical manufacturing, processing, handling, and shipping. Nitrogen has low reactivity and it is excellent for blanketing and is often used as purging gas. It can be used to remove contaminants from process streams through methods such as stripping and sparging. Due to its properties it can be used for protection of valuable products against harmful contaminants. It also enables safe storage, usage of flammable
compounds and can help prevent combustible dust explosions.

Industrial nitrogen gas can be produced by either separation of gaseous air using adsorption (PSA) or fractional distillation of liquefied air using cryogenic methods.

NITROGEN USE BY PURITY
PSA can produce nitrogen at various range of purities. The lower the purity, the lower is the cost of nitrogen production. For example, the quality of vegetable oil can be maintained by blanketing with 99,5% nitrogen purity. Normal nitrogen purity for food processing is in the range from 99% to 99,5%. Lower purity nitrogen in the range from 96% to 99% is often used in fire and explosion prevention. High purity with nitrogen content from 99,9 % to 99,999 % is typically used for laser cutting, electronics soldering and pharmaceutical applications.

Oxygen, is present in the air with concentration around 21 %. Oxygen is at atmospheric conditions always present in gas phase with no odour, colour or taste. It is a highly reactive substance, reacting with almost all elements, except inert gases.
This is why it is used in a variety of applications: aquaculture, feed gas for ozone generators, glass blowing, leaching, NOx reduction for fuel burners, oxygen lancing, welding and health care.

Oxygen gas can be produced by either separation of gaseous air using adsorption (PSA) or fractional distillation of liquefied air using cryogenic methods.

OXYGEN USE BY PURITY
PSA can produce oxygen at various ranges of purities. Typically purity of the oxygen produced by PSA is from 90 % to 95 % of the oxygen. The lower the purity, the lower is the cost of oxygen production.