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Inert gas (nitrogen, argon) Water
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Figure 9 Close-up of turbocompressor inlet guide vanes
Figure 10 ‘Sweet spots’ for refrigerants in terms of specific temperature ranges and low cost. For these reasons, Atlas Copco Gas and Process heat pump compressors use natural refrigerants, specifically hydrocarbons, water, inert gases (nitrogen and argon), and carbon dioxide (though, if requested, machines with HFCs and ammonia as the working fluids are also available) (see Figure 10 ). Summary There are three obvious reasons for using heat pumps: CO₂ emissions reduction, cost reduction (fuel savings, CO₂ emission certificates, tax breaks, and so on), and security of supply. The heat pump as an industrial technology has been mature for decades, but it has existed for years in the shadow of fossil fuels due to what appeared to be a lack of need. Now, however, with sustainability demands and the price of fossil fuels, it is fair to say that the age of the heat pump is beginning. Moreover, regardless of the motivation behind the investment decision for an industrial heat pump, in the end it is a further step towards the decarbonisation of industry, and this is something urgently needed to meet the goals of the Paris Agreement.
geared turbocompressor brings significant COP results, even though the machine setup remains simple because only one drive motor is required. Compressor stages can be precisely controlled via inlet guide vanes to compensate for fluctuations in heat demand. Due to this entirely mechanical control, expensive power electronics for speed control can be dispensed with in most cases. Especially in critical applications in large production plants, a simple, mechanical power and capacity control is usually a preferred option. Customised systems welcome Nevertheless, heat pump technology is reliant on refrigerant, whose beneficial properties enable the required high COP values. Many systems with lower performance use components from the HVAC (heating, ventilation & air conditioning) industry, which is why established, latest-generation refrigerants such as HFCs (hydrofluorocarbons) like R1233zee and R1234yf are also used here. There are, however, potential issues regarding the environmental impact and future phase- outs of some refrigerants. In addition, with filling quantities in the ton scale, the high price of HFCs is accompanied by their heavy weight. In contrast, natural hydrocarbons in the form of liquefied petroleum gas/LPG are freely available
Rasmus Rubycz rasmus.rubycz@atlascopco.com
www.decarbonisationtechnology.com
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