Page 68 - Industrial Plants 2014

Fig. 6 – Dual-phase definitely expensive (up to 10 MW during winter) and
compact filter must be defined very carefully;
• oil mist close to air intakes: on the roof of the power
plants it is common to find a chimney for oil mist
coming from the lubrication system of rotating
equipment. If this oil mist is unfiltered by an
appropriate system, it will simply enter the air intake
and the air filters;
• air intake too small: whenever the air intake is too
small and the flow rate for each filter element is too
Fig. 7 – New stainless high (5000 m³/h) severe problems with pressure
steel silencers drop are evident;
• pulse jet cartridges: this type of filter is extensively
used in Middle Eastern desert conditions. Employing
pulse jet cartridges in a clean environment can
cause a high pressure drop with no benefit to the
gas turbine;
• position of the air intake: when there is a green-field
project for a new power plant, the gas turbine air
intakes must be a sufficient distance (or at least not
Other aspects and commonly- in the downstream wind direction) from dirty, dusty
encountered problems sites. It is also imperative that sufficient space is
provided away from the cooling towers, which can
Besides air filters, as previously mentioned, there are wet the filters and increase pressure drop.
several technical points that can be improved in an air •
intake:
• anti-icing system: in some cases the anti-icing Conclusions
system is behind the filters, allowing ice to form on The two case studies and field experience has shown
the filters. This has a dramatic effect on pressure the huge potential to increase the energy efficiency of
drop; increasing by up to 2000 Pa. Furthermore, gas turbine through a few, straightforward actions of
bleeding from gas turbine for anti-icing can be retrofit to existing air intakes.

Thomas Helf

Thomas Helf is Product Manager Powergen & Industrial – Retrofit, Mann+Hummel Vokes Air

Carlo Coltri

Carlo Coltri was born in Milan in 1970; he has a degree of air intake filters for gas turbines.
in Engineering at Politecnico di Milano. Since 2011 he is also responsible for corporate
His experience in Energy business started with KSB business development of Power Generation Unit for
Italy (pumps and valves), as marketing manager and as Vokes Air Group.
a key account manager for the Business Unit Energy. He is member of steering committee of energy sector
Currently holds the position of Country Sales Manager of Animp and member of advisory board of Power
for Vokes Air in Italy, Swedish multinational manufacturer Turbine Europe.

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