26 PROjECT PRIDE
cost in case of higher footprint area of RABH is nullified.
Thereby after analysing the overall operation cost and
lesser maintenance, RABH has been preferred over PJBF
for kiln/raw mill application. For Dalmia DSP Unit-I an
additional 10% volume margin has been considered to have
better bag life and lower pressure drop in the system.
Turbo Blowers
Turbo blowers are latest technology blowers with magnetic
air foil bearings which have no contact and hence are
energy efficient systems. Also it has lesser maintenance,
higher reliability, lower noise emissions, lesser vibrations,
no lubrication requirement, and lower footprint area when
compared to conventional/PD blowers. The most critical
requirement of this system is a dust-free environment as
the machine’s speed is in range of 20,000–30,000 RPM.
Power savings in case of turbo blowers are around 30% as
compared to conventional/PD blowers. These blowers can
be controlled to have lower volume output as it has inbuilt
VVFD.
However turbo blowers can be used for all the
applications, it was analysed that, on account of power
savings, turbo blowers were justified only in those
applications where higher volume is required. Therefore,
turbo blowers were considered over PD blower for kiln
and calciner firing along with primary air application. For
other applications hybrid/tri-lobe blowers were considered
in place of twin lobe to have better efficiencies.