Proper air filtration is critically important to the overall reliability and working of gas turbine filters. Fuel costs make around 80 percent of the total life cycle cost of electricity. Small gains in efficiency also mean huge savings. With fuel costs of almost $16.00/mmBTU and higher in some global regions, the operational savings may be achieved via better compressor performance and using High Efficiency (HEPA) air filters. Operators can greatly reduce their maintenance costs because of a much cleaner engine, quantified by minimal number of inspections, fewer shutdowns, as well as higher availability. Gas turbines can maintain optimum GT efficiency across the entire life of the filter. This article highlights he decision criteria that is valuable in choosing the optimum gas turbine filter solution, with an objective of maximizing gas turbine availability and reducing the operating costs.
The aero derivative gas turbine ventilation and combustion air filter systems are developed to guard the gas turbine, equipment compartments and generators from the impacts of contamination, air-borne dirt, and foreign objects. Various inlet conditioning options are also there to maximize the gas turbine filter performance.
Most of the advanced gas turbines available nowadays use a three-section inlet air filter that is mounted directly over the turbine enclosure, conserving the space and offering compact, low-pressure loss ducting in the turbine inlet.
The ventilation and combustion air filter system are made up of a filter house structure, fans, roof-mounted silencers, and related ductwork all placed on the turbine and generator enclosures. The filter house is made up of weather hoods, chiller, filter elements, or anti-icing coils, and plenum chamber assembly. Air from a plenum assembly is ducted into the turbine engine intake for the combustion and to the generator and turbine compartments for ventilation and cooling. An external walkway and ladder with the access doors to the air filter structure are there that facilitate filter servicing.