Adaptation of F-gas Regulations in a Medical instrument

Sammanfattning

Fluorescent greenhouse gases are used as refrigerants in many applications and have a very high global warming potential. New regulations to combat climate change have been decided upon in the EU parliament and US congress. Repercussions involve the use of substances with GWP>150. In short, HFC refrigerants, such as the common R134a, will be banned. This calls for fast actions in order to find replacement refrigerants, one of which comes in the form of the natural gas, R290, also called propane. R290 has a dramatically lower global warming potential compared to most others, but comes with the feature of being highly flammable. The aim of this study is to investigate the alternative cooling solution in the application of a medical instrument. This study looks to find and test three replacement chillers in the automated medical instrument Phadia 1000, used to test for allergens in patients blood samples. The study investigates how a new cooling system should meet design requirements, it involves both theoretical calculation and practical testing of heat loads. It presents three replacement chillers that use refrigerant R290 and tests them in various conditions to ensure that they meet instrument specifications. The study results in comprehensive data that shows the chiller performance. Results are analyzed and multiple aspects are brought forward where climate impact is of high importance. Solutions are discussed and culminates in chiller C as the most suitable replacement, due to its high cooling capacity, low requirement of instrument modification for implementation and low global warming potential.