Frequently Asked Questions
Why we need Filtration
Any rotating machinery (Compressor, gas engine, Diesel engine, gas turbine etc.), due to its design Takes the enormous amount of air. All rotating machinery or power systems are sensitive to air quality. Filtration is applied to provide protection against the effects of contaminated air that may degrade the performance and life due to: erosion, fouling, corrosion, and cooling passage plugging. The need for proper filtration has increased in significance due to the complex designs of the advanced technology power systems.
How environment conditions effect the filtration solution
Properly selecting and maintaining the filtration system can increase the performance and life of power system and minimize the required and unexpected maintenance. Proper filtration system selection includes a review of filter characteristics related to performance, operation, life, and maintenance. Considerations for environmental factors are discussed with a focus on humid, desert, subzero, marine, coastal, offshore, and land-based applications. Finally, a methodology for a life cycle cost analysis for filter selection is presented.
What factors to be considered for filter system operation in wet environment.
Experience has shown that the pressure drops across certain filtration systems suddenly increases during the occurrence of fog and for many hours after the fog has cleared. If the environment where the power systems is operating has high frequency of moisture entrainment in the filtration system, then this should be accommodated for. Droplet separator and synthetic bag filter and coalesce filters can be used to remove the droplets of moisture.
Filter fiber materials can be selected for wet operation. Also, the operator should expect to have a reduced filter and power systems performance during periods of wet operation.
What is droplet separation stage?
Vane separators are used to remove water droplets from the airflow to protect equipment from corrosion or filters clogging. They can be installed either on ventilation systems or on combustion air intakes. It’s common to find these moisture separators suitable for horizontal flow being used on static combustion air intake filter casing for gas turbine, compressor and engines.
The vane type separators are effective for water particles greater than 10 microns. The double type pocket separators are also effective for capturing particles in the range of 5 to 10 microns. The efficiency of the separators is based upon the design air velocity. The separator will have the highest filtration efficiency at its design velocity. Vane separators have a relatively low-pressure loss (0.1 to 0.5 inH2O). They are effectively used for removal of water in high velocity filtration systems which are used in marine and offshore applications. Aluminum, stainless steel, or PP, PVC are used as the material of construction, due to their corrosion resistance properties.
What is pre-filtration stage?
The air has a spectrum of different particles sizes. If only one-stage high efficiency filter is used, the buildup of large and small solid particles can quickly lead to choking of filter element, increased pressure loss and filter loading.
Prefilters are used to increase the life of the high efficiency filter by capturing the larger solid particles. This allows the high efficiency filter to only remove the smaller particles from the air stream which increases the final filter life.
Prefilters normally capture solid particles larger than 10 microns. Some prefilters will also capture the solid particles in the 2 – 5-micron size range. These filters usually consist of large diameter synthetic fiber in a disposable frame structure. Bag filters are also commonly used for prefilters. These offer higher surface area which reduces the pressure loss across the filter.
What is oil bath filter system?
There are other filters that and are effective for removing certain contaminants. Rotating oil-bath filters use oil to capture dust, creating a sludge that needs to be cleaned by settling tanks or centrifugal motion. The type of oil needs to be matched to the type of dust.
The self-cleaning viscous air filter or oil bath filters is particularly suitable in many industrial applications to filter large air volumes with high dust concentrations. They are generally used in used in diesel and gas engine applications. It maintains its dust trapping characteristics over an extended period of time and dust will not break away and be carried downstream.
They are one of the most cost-effective technologies to protect your installation from the sand and dust. The time-controlled rotation and the immersion of the panels in the oil tank ensure filter self-cleaning and maintain a constant pressure drop and filtering efficiency. For larger air capacities, single filters can be assembled to form multiple banks. Even in very dusty environment, pressure drop across the viscous surface filter doesn’t exceed 250 Pa..
What is Inertial filter system?
Inertia separation is an excellent pre-filtration system, particularly suitable in environments with high dust concentration as desert areas, mines, steel and foundry factories and cement industries.
This filtration system is based on the kinetic energy conservation principle, for the dust particles transported by the upstream flow; with a series of quick direction changes, the fluid flows are directed towards the area where clean air is needed, whereas the particulate, through inertia, continues to flow towards an area of the filter that exhausts the separated dusts.
Why we need anti icing system?
One major cause of static filter failure in sub-zero temperature climate is the formation of frost. Depending on the weather conditions such as temperature versus relative humidity, frost then ice on the air filters will lead to filter clogging / reduce the airflow. At some point, the equipment is not able to operate in satisfactory conditions and is tripped / stopped.
Infrared heating systems prevent freezing of air intake filters of gas power and gas compression stations in the cold season. Infrared heating for anti-icing can be integrated into the filtration system to make it more efficient and to save energy.
Infrared anti-icing wes developed taking into account the constraints of the application, in particular to resist to shocks and vibrations.
