EVENTS AND EXHIBITIONS
INCORPORATING COLD CHAIN
Bock CO 2 seminar
educates industry
By John Ackermann
In the GEA Bock CO 2 one-day seminar held in February in Johannesburg
and Cape Town, delegates were informed of the strides made internationally
towards greener and more sustainable refrigeration.
C
O 2 refrigeration systems,
particularly in supermarkets, is
growing in popularity, not only
in Europe, but also in South Africa. As a
zero ozone depleting substance and
with a global warming potential (GWP)
of only one, there is no threat of CO 2
being phased out or phased down by
environmentalists. The properties of CO 2
are well known and has been used as a
refrigerant for decades.
When introduced into supermarket
refrigeration in South Africa, the resistance
by the market stemmed from lack of
skills to handle the extreme operating
pressures, availability of components and
compressors and capital costs. Designing
CO 2 systems for maximum efficiency
requires a good understanding of the
thermodynamic properties of CO 2 and
its application in sub-critical, trans-critical
and cascade systems.
Europe’s F-gas regulations, the inclusion
of HFCs in the Montreal Protocol and
the Kyoto Agreement, intensified the
quest for refrigeration systems with the
lowest environmental impact. Chemical
manufacturers have responded with low
GWP refrigerants. Governments have
imposed carbon taxes. Regulations have
revised safety standards for flammable
(HCs) and toxic refrigerants (ammonia).
Component manufacturers have designed
for high pressures and less leakages.
GEA Bock has responded with a
range of compressors for the full range
of synthetic and natural refrigerants, and
from low to high cooling capacity.
Naeem Fakir, product line manager –
Bock, assured delegates of a generous
local stock holding of compressors
to serve the African market. Based
in Johannesburg, Fakir is familiar with
conditions in South Africa, in neighbouring
countries, East and West Africa. He explains
further, “The supply of compressors is only
part of our offer. The GEA Group offers a
complete solution package, supported
with application know how.”
GEA Bock, with an annual production
of 50 000 semi-hermetics, has optimised
its HG range to cater for a wider range of
refrigerants, higher cooling capacities and
a reduction in life cycle costs. “The new
four-cylinder HG44e offers a wider range
than its predecessor HG44. Part of the
HG5 and HG6 has been replaced with the
HG56e. The best features of the HG44 and
HG5 and HG6 have been incorporated
into the new range. Improved valve
plate design, easy to remove oil strainer,
added thrust washer to prevent galling of
crank shaft and oil pump