In spray painting, CO 2 , which mixes well with paint polymers, is used as
propellant alternative to VOCs. This technology has been developed by Union
Carbide and is marketed under the tradename UNICARB.
Similarly, CO 2 is used since long time as a propellant in many aerosol applications, notably as replacement of CFCs, which are well known to damage the
Earth’s ozone layer.
SC-CO 2 is used for cleaning electronic components as well as for the removal of
hydrocarbon machine coolants from metal parts. Specifically, it is currently being
investigated for possible application in a vast range of cleaning, extraction, and thin
metal film deposition applications for semiconductors and electronics. It is foreseen
to have potential commercial application in the areas of information storage devices, semiconductor devices, electrical and electronic components, precision optical
devices, inertial guidance systems, medical equipment and devices, and metal
finishing. While competition from established cleaning methods may seem severe,
there are a number of attractive features which single out the supercritical carbon
dioxide process as a unique method for precision cleaning. These include environmentally compatible cleaning, low carbon dioxide cost and overall cost, rapid
processing, ability to clean large areas and complex shapes, ability to form
homogeneous cleaning supercritical fluids for general cleans as well as the ability to
incorporate additives to tailor more specialized and specific cleaning.
In all cleaning applications, SC-CO 2 guarantees high efficiency and effectiveness
in contaminant removal, while responding to the stringent deadlines and aggressive
scheduling imposed by legislative bodies to phase out the production and use of
ozone-depleting substances such as CFCs and to reduce the noxious Volatile
Organic Compounds (VOCs) emission derived from the use of organic solvents.
Reducing worker exposure to VOCs is also a mandate in the electronic industry.
This is a market that will grow in time.
8.3.7 Fluid in Air-Conditioners
The substitution of CFC in air-conditioners would reduce the environmental impact
of air cooling in civil and industrial buildings and in mobile cars. CO 2 has been
proposed as an interesting candidate. Norsk Hydro ASA (Oslo) and a Norwegian
university have developed a CO 2 -based cooling system for automobiles. Daimler
Chrysler AG (Stuttgart) has tested the Mobile air Conditioning 2000, and Norsk
claims the technology competes favorably in price, weight, space, and energy
efficiency with the CFC based one. Likewise, Sanyo Electric Co. (Tokyo) has
developed a closed-type rotary compressor that uses CO 2 as coolant agent.
Complete CO 2 based refrigeration systems (YARA-Thermoking) [11] are trying
to gain market share at the expense of mechanical refrigeration systems based on
CFCs as the former reduce the environmental impact and are less expensive (lower
CAPEX and OPEX). As a matter of fact, CO 2 -based systems are silent and require
little maintenance, reach the target temperature more rapidly and hold it longer.
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8 Use of CO 2 as Technical Fluid (Technological Uses of CO 2 )
propellant alternative to VOCs. This technology has been developed by Union
Carbide and is marketed under the tradename UNICARB.
Similarly, CO 2 is used since long time as a propellant in many aerosol applications, notably as replacement of CFCs, which are well known to damage the
Earth’s ozone layer.
SC-CO 2 is used for cleaning electronic components as well as for the removal of
hydrocarbon machine coolants from metal parts. Specifically, it is currently being
investigated for possible application in a vast range of cleaning, extraction, and thin
metal film deposition applications for semiconductors and electronics. It is foreseen
to have potential commercial application in the areas of information storage devices, semiconductor devices, electrical and electronic components, precision optical
devices, inertial guidance systems, medical equipment and devices, and metal
finishing. While competition from established cleaning methods may seem severe,
there are a number of attractive features which single out the supercritical carbon
dioxide process as a unique method for precision cleaning. These include environmentally compatible cleaning, low carbon dioxide cost and overall cost, rapid
processing, ability to clean large areas and complex shapes, ability to form
homogeneous cleaning supercritical fluids for general cleans as well as the ability to
incorporate additives to tailor more specialized and specific cleaning.
In all cleaning applications, SC-CO 2 guarantees high efficiency and effectiveness
in contaminant removal, while responding to the stringent deadlines and aggressive
scheduling imposed by legislative bodies to phase out the production and use of
ozone-depleting substances such as CFCs and to reduce the noxious Volatile
Organic Compounds (VOCs) emission derived from the use of organic solvents.
Reducing worker exposure to VOCs is also a mandate in the electronic industry.
This is a market that will grow in time.
8.3.7 Fluid in Air-Conditioners
The substitution of CFC in air-conditioners would reduce the environmental impact
of air cooling in civil and industrial buildings and in mobile cars. CO 2 has been
proposed as an interesting candidate. Norsk Hydro ASA (Oslo) and a Norwegian
university have developed a CO 2 -based cooling system for automobiles. Daimler
Chrysler AG (Stuttgart) has tested the Mobile air Conditioning 2000, and Norsk
claims the technology competes favorably in price, weight, space, and energy
efficiency with the CFC based one. Likewise, Sanyo Electric Co. (Tokyo) has
developed a closed-type rotary compressor that uses CO 2 as coolant agent.
Complete CO 2 based refrigeration systems (YARA-Thermoking) [11] are trying
to gain market share at the expense of mechanical refrigeration systems based on
CFCs as the former reduce the environmental impact and are less expensive (lower
CAPEX and OPEX). As a matter of fact, CO 2 -based systems are silent and require
little maintenance, reach the target temperature more rapidly and hold it longer.
132
8 Use of CO 2 as Technical Fluid (Technological Uses of CO 2 )