Page 66 - Industrial Plants 2014

time, has increased the efficiency of prefiltration was still in service and operating with a low pressure
(from G4 to M5) better protecting the final filter; drop.
• the total initial pressure drop of the (Macrogen GT Previous research has generally confirmed that a 50 Pa
Duo-equipped) turbine A was 165 Pa, significantly saving in pressure drop corresponds approximately to
lower than turbine B (275 Pa) configured with an increase in the efficiency of the turbine of 0.1%.
coalescer pads, G4 bag prefilter and the same F9 The chart of figure 3 summarises the results of the test
final filter. and the savings regarding pressure drop.
Just considering the initial pressure drop, gas turbine A
Other points of note are: (with Macrogen GT Duo) has yielded a reduction of
• the behaviour of Macrogen GT Duo was much more more than 100 Pa compared with gas turbine B. This
stable than the solution with coalescer pads; after pressure drop saving increased over time, especially as
nearly 5,000 running hours the total pressure drop the coalescer pads became dirty and wet.
was 220 Pa; This means that the gas turbine A has seen an increase
• the parallel solution B showed a total pressure drop in efficiency of at least 0.2%. This was achieved just by
of 350 Pa after just 2200 hours, at which time it was changing the filter stages and without any investments
necessary to change the coalescer panels; in retrofitting. Such performance represents a huge
• in December 2013, the filtration system of turbine A saving for the operator, especially considering that the

Fig. 2 – Pressure
drop performance
of gas turbines A
and B

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