RACA Journal August 2023 | Page 50

48
Technical

PROPANE AS A REFRIGERANT :

APPLICATIONS , SPECIALTIES , HANDLING

Prepared and supplied by BITZER .
Propane ( R290 ) is a colourless and odourless gas that belongs to the family of hydrocarbons .

Propane is a highly efficient refrigerant that has gained popularity in recent years due to its excellent thermodynamic properties and low environmental impact . This article will discuss the applications , specialties , handling , and future outlook of R290 in refrigeration systems .

Propane has a low global warming potential ( GWP ) of 3 and zero ozone depletion potential ( ODP ), making it a viable alternative to conventional refrigerants with high GWP values . It has been used in various refrigeration and air conditioning applications , including commercial , residential , and industrial settings . R290 is commonly used in small-scale refrigeration systems , such as refrigerators , freezers , and air conditioning units . Additionally , it is also used in larger commercial and industrial refrigeration applications , such as food storage and processing , chemical processing , and cold storage .
OVERVIEW OVER FLAMMABLE REFRIGERANTS According to the ISO 817 standard , today ' s refrigerants can be classified into categories A and B . While category A includes non-toxic substances , category B includes toxic refrigerants . Flammability is classified in four groups ( 1 = non-flammable , 2L = flammable with slow flame spread , 2 = flammable , 3 = highly flammable ).
Photo BITZER
The most important substances of safety group A3 that can be used as refrigerants are hydrocarbons such as propane ( R290 ), propene ( R1270 ), isobutane ( R600a ), butane ( R600 ) or ethane ( R170 ), which have a long history in refrigeration and air conditioning technology and were a model for the development of many synthetic refrigerants . Group A3 refrigerants are highly flammable . They can be ignited at proportions as low as about two and as high as ten percent in the air . In the medium mixing range , ignition can be achieved by the spark of a light switch , a steel tool falling on a stone floor or a statically charged sweater , causing violent deflagrations or explosions . The combustion residues are in particular carbon dioxide and water and thus in themselves usually harmless when everything has cooled down again .
SPECIALTIES OF R290 IN REFRIGERATION SYSTEMS The use of flammable substances has a long history in household appliance technology and commercial refrigeration . Towards the end of the 19th century , the use of the non-toxic but highly flammable hydrocarbons became widespread due to their good thermodynamic properties , along with ammonia , sulphur dioxide and carbon dioxide . Propane ( R290 ) is well suited to commercial refrigeration and also for air conditioning and heat pumps . It boils at -42 ° C and can cover evaporating temperatures of -40 ° C and higher . Large temperature strokes are easily possible when compressing with this substance .
R290 has a high cooling capacity , which means it can remove a large amount of heat in a short amount of time . It also has a high coefficient of performance ( COP ), which measures the efficiency of the refrigeration cycle .

48

BITZER offers a comprehensive product portfolio for use with flammable refrigerants such as the CSH compact screw compressor .
RACA Journal I August 2023
HOW TO SECURE SAFETY IN REFRIGERATION SYSTEMS WITH R290 R290 is a highly flammable gas that could pose a safety risk if not handled properly . Therefore , propane-based refrigeration systems must be designed and installed with safety features that minimize the risk of fire and explosion . These safety features include pressure relief valves , flame arrestors , and leak detection
www . refrigerationandaircon . co . za