NEWS
FULL STEAM AHEAD
THE ANSWER FOR STERILISATION AND THERMAL LOADS In more recent issues, we have discussed the benefits of clean steam for sterilisation and how this helps provide security for sterile loads within CSSD however in this issue we will explore the wider energy benefits when considering the system as a whole. To re-cap, it all boils down, excuse the pun, for the need of heat energy. Traditionally this energy has come from the combustion of fossil fuels but, as it is not practical to light a fire under every process that needs heat energy, steam becomes an ideal medium as it retains a large volume of heat energy relevant to its mass, gives up its energy when condensing and can be transported easily (i.e simply via pressure drop) . As we pointed out in volume 43, the desire to move away from fossil fuels is constantly evolving however this doesn’t disclude the fact that steam itself remains the most efficient energy carrier. What changes is the way its generated and how its utilised. Often it’s thought an alternative means for heat generation can be via electricity however the infrastructure required to generate and supply (both transmission and distribution within a HSO facility) in comparison would be immense. In addition if the power grid supplying a HSO is still generated by fossil fuels, then the question is posed, “how does this change anything”. Its just adds more load to the grid, not reduce it. The combustion of fuel to provide energy to thermal processes will continue to be a key consideration, but this is not to say that it cant be done in a renewable fashion. Biomass and hydrogen are possible renewable energy sources that are in the not too distant future and in the mean-time, locally steam systems can be made more efficient by focussing on energy recovery and utilising the thermal capacity of the plant to service as many energy using assets as possible, reducing the need for other energy sources.
This can be in combination with site based renewables such as solar and or co / tri-generation. The basics still have their place, improving condensate return volumes, recovering energy from flash or low pressure sources and considering high efficiency burners for steam generation are all widely available however what of other waste heat streams. Hot flue gasses, compressors, chillers, solar and even hot effluent can be considered a potential source of thermal exchange, recovering energy and saving on thermal loads in other areas of the hospital. In summary, there are many ways of creating a thermally efficient, sustainable and economical steam plant whilst not compromising on the evolving need for improved sterility and repeatability of the sterilisation process. Using steam as the energy transporter remains the universal choice for meeting the a HSO’s thermal needs, we just need to be smarter on how heat is re-captured and utilised. As always, we must continue to measure and monitor our energy intensity in order to justify and uncover energy saving opportunities in a HSO and as thermal generating sources become more advanced, will ultimately improve environmental sustainability. Regardless steam remains relevant and should be part of a evolving HSO’s infrastructure. https://www.spiraxsarco.com/global/en-AU/contact-us
Figure 1 – A modern steam plant layout Figure 2: A General overview for Steam utilisation in a Hospital
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