Progress in freezing and cooling in the
20th Century often was measured by new,
man-made refrigerants. Now industry is
rediscovering natural solutions.
Consider closed-cycle air refrigeration (CCAR). A few years ago, CCAR was viewed as sufficiently promising for flash freezing in food processing to warrant a $2.1 million development grant from the U.S. Department of Commerce's Advanced Technology Program. Dry air pressurized to 1,200 psi serves as the refrigerant. The technology has the ability to chill products cost effectively at temperatures ranging from -60°F to -150°F. Cooling costs are pegged at half that of cryogenic flash-freezing systems with which CCAR competes.