Gas Filtration Selection

The article describes filtration of hydrocarbon gases with non-condensed drops and solid particles. Liquid drops and solid particles deteriorate operation of gas equipment. They especially badly compressors of different types.

When solid particles enter compressor unit they cause increased wear of the flow part. Big particles will be followed by erosion wear and can be the reason of rotor jamming.

The presence of liquid in hydrocarbon gases can cause condensation during the process of compression depending on the ratio between pressure and temperature.

While working out a project adequate protection of compressor blocks and other elements of gas transport system should be foreseen.

Removal of solid particles can be done with the help of cyclone filters due to centrifugal forces. They throw solid particles out to the side surface of cyclones and provide required filtration grade.

Small suspended particles, especially liquid drops of heavy hydrocarbons, cannot be removed effectively by cyclone filters. In this case usage of fiber multilayer filters will be needed. This type of filters is often called filter-coalescers.

Such coalescent filters should be installed in gas pipelines only after primary cleaning filters which remove big solid particles and drops of condensate. Primary and coalescent filters can be installed consistently in the same housing.

Selection of coalescent filters depends on gas composition, the size of solid particles, gas pressure at the inlet of filtration unit and required grade of filtration measured in microns.

Coalescent filters can effectively remove small mechanical impurities.

They allow to drain partly water condensate and the heaviest hydrocarbons partly which saturate gas up to the dew point temperature. Due to coalescent filters protection of compressor unit is provided. Coalescent filters are used as desiccants in case of air compression.

However, filters-coalescers don’t influence considerably dew point temperatures for hydrocarbon gases. It is necessary to apply glycol dehydrators to change water and hydrocarbon dew point temperatures when gas is in a saturated state.

While processing the gas supplied by Gazprom subsidiaries it will be actual to remove only solid particles. Natural gas from Gazprom is transported in a dehydrated condition.

If there is a considerable quantity of liquid fractions in gas the housing of coalescent filters is equipped with level sensors for drainage of accumulated condensate.

Selection of filters-coalescers for different types of hydrocarbon gases is fulfilled empirically. The quality of filters depends on qualification of engineers who are responsible for their selection.

Compressorturbo helps to find proper filtration system for any type of gas and gas processing.