22:38 PM | September 26, 2016 | Ray Will
While refrigerants have been hard at work keeping our food fresh and living spaces cool, their composition has been evolving over the last 150 years. While largely trouble free today, the birth of commercial refrigeration began with the use of some unfriendly chemicals. The following summarizes major events through four generations of refrigerants development:
Generation 1—In the mid-1700s, artificial refrigeration was developed in the laboratory using evaporation of volatile chemicals. By 1834, the first vapor-compression refrigeration system was developed using ammonia, but the first commercial refrigeration systems were not developed until the 1850s using ammonia, methyl chloride, various hydrocarbons and sulfur dioxide.
Generation 2—In household- and smaller-scale refrigeration first-generation refrigerants were replaced by chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs) in the 1930s. CFC and HCFC refrigerants are chemically stable, nontoxic, and nonflammable. CFCs and HCFCs grew steadily over the next four decades in a wide range of applications The vast majority of second-generation refrigerants are based on fluorine, derived fluorspar.
Generation 3—In the 1970s, it was determined that CFCs contributed to the destruction of stratospheric ozone. The international accord Montreal Protocol called for a phased elimination of CFCs and the HCFC transition products. They are being replaced by hydrofluorocarbons (HFCs). Although these products do not deplete the ozone layer and are relatively nonflammable and chemically stable, they are potent greenhouse gases.
Generation 4—The latest generation is driven by hydrofluoroolefins (HFOs)—a group of alternative refrigerants that have no impact on the ozone layer and have an extremely low global warming potential (GWP). These products have been commercialized within the last 10 years, and they have better performance and are more energy efficient than the refrigerants they replace.
Although the progression appears to be linear, chemical refrigerants from each prior generation are still in use today. Ammonia refrigerant remains and is typically the standard in large-scale industrial refrigeration. And some generation-one refrigerants are resurging as replacements for refrigerants with medium-to-high GWP.
These continuing changes in the mix of refrigerants in use have profoundly impacted the chemical industry as companies have raced to provide ample quantities of acceptable products as mandated by environmental regulations. This race to supply new capacity is ongoing as generation-four HFOs based on fluorine continue to be introduced, particularly in mobile air conditioning as HCFCs and HFCs also based on fluorine are being phased out.
Refrigerants are one of the key topics to be discussed in an upcoming conference, Fluorspar 2016 in Toronto, Canada, 25–26 October. Supply and demand for fluorine and its principle source, fluorspar, will be discussed as well as how these changes in the refrigerant market will impact the chemical industry supply chain. The conference also provides the opportunity to network with the major fluorine producers and consumers.
Ray Will is a director of IHS Chemical Consulting, where he conducts business analysis and strategic planning for the specialty and inorganic chemical sectors.