Projects
BEFORE:
Generator
plant room
in 1997.
integral speed drives were installed to ensure optimum
performance, ease of maintenance, and better utilisation of
the limited plant room space.
Water generation system
A new snow smelter with increased capacity was installed just
below surface level, approximately 200m east of the base.
Particular attention was paid to increase the thermal insulation
of the snow smelter, thereby increasing the efficiency of the
heating system (in line heaters versus the old dry elements)
and improving the control system.
Vertically configured Wilo pumps are used both for
continued circulation of the water between the two snow
smelter tanks and to pump water to the base. Inside the base,
water is stored in six insulated, stainless-steel storage tanks
installed against the east wall of the hangar. Each tank has a
capacity of 6 367ℓ, providing a total storage capacity of just
over 38 000ℓ.
Water is continuously circulated through the base via a
set of bag filters and an in-line heat exchanger. The decision
to use bag filters of 95 micron was based on two criteria: less
space required comparing a bag versus a cartridge system for
the flow rate required, and also because replacement bags are
cheaper compared to filter cartridges.
The effluent collection system installed in the mid-
nineties was of the standard cistern and urinal type, with
gravity draining from the second floor ablution facilities to
underfloor tanks in the links. Effluent was pumped from
these tanks to a standard biological reactor wastewater
treatment plant in Block C.
Continued on page 52
www.hvacronline.co.za
RACA Journal I January 2019
49