Traditional air filtration systems for Gas Turbine Naval applications consist of 3 stages: 1st vane separator + pocket filter + 2nd vane separator. The 2nd vane separator is required to drain out droplets formed by the traditional pocket filter during its coalescing function.
Further to technological advancements in the water repellency of filter media, as well as leak-free techniques, it is now possible to implement a pocket filter that avoids leaching water droplets downstream. This enables the elimination of the 3rd stage vane separator in the air filtration system. The result is a suitable 2-stage air filtration system.
The elimination of the 3rd stage vane separator provides the obvious following advantages:
• Reduced pressure drop
• Reduced weight
• Reduced foot-print
• Reduced cost
Latest technological advancements in water repellency and high efficiency melt-blown media also allow the attainment of higher performance such as:
• Increased efficiency against water droplet and salt in wet state
• Increased efficiency against dry salt and dust
This results in higher cleanliness of the Gas Turbines with benefits in terms of compressor fouling, compressor blades corrosion and turbine blades hot erosion.
Higher performance also results in simplified maintenance as technicians need only focus on the replacement of the elements as opposed to the cleaning and overhauling of the intake duct.
The paper goes through the engineering challenges of evolving from a 3-stage to 2-stage filtration system.
The paper provides data from testing at independent laboratories with results that back the claims. Furthermore, reference is made to Offshore Oil & Gas installations and testing that have proven successful with independently measured data.