1.1.1 Cryogenic Engineering Prior to the Eighteenth Century
The word Cryo- originates from the Greek kruos, meaning icy cold. Cryogenic temperatures are usually considered those below −150°C, which covers the normal boiling point of most gases (except for the so-called permanent gases including hydrogen, oxygen, nitrogen, carbon monoxide, and the inert gases). Cryogenic engineering covers the technologies used to produce these cryogenic temperatures. Cryogenic engineering is not fundamentally different from refrigeration, defined as “to make things cold.” However, refrigeration originated much earlier and is closely related to food preservation. Bacteria grow rapidly in many foods including meat, fish, fowl, and dairy when exposed to room temperature and above. Bacterial activity is suppressed at lower temperatures, and temperatures below −20°C inactivate any microbes (bacteria, yeasts, and mold) present in food. In addition to other food preservation techniques, such as drying, fermenting, pickling, smoking, curing, canning, and the like, storing food at freezing temperatures became an effective preservation method. Ice is the most obvious and natural “cryogenic engineering instrument.” In fact, the Chinese began to use crushed ice in food about 2000 BC [1].
Food preservation for sailors in earlier times posed a significant challenge, since it was not unusual for voyages to last many months. For example, eighteenth-century German immigrant ships bound from England to Philadelphia typically sailed for 60 to 80 days, and many sea voyages lasted even longer. Since sailing ships had limited capacity for storing ice, meat and fish could only be carried in small quantities, and their use was normally strictly rationed. These storage limitations became even more severe when ships traveled in warmer geographic areas because any ice used for preservation would melt quickly.
The ice industry was a significant industry for centuries, but obtaining, preparing, distributing, and storing natural ice was expensive. As the industrial age progressed, the search began for alternatives to naturally formed ice: “necessity is the mother of invention.” The word “refrigeration” was first used at least as early as the seventeenth century. The search began at that time for a “refrigerator” or “ice maker” that was able to produce ice at a lower cost.
1.1.3 Mid-Nineteenth Century: Realization of the Vapor-Compression Refrigerator That Produced Ice!
Oliver Evans (1755–1819) [3], remembered as the “Grandfather of Refrigeration,” introduced the idea of “Vapor-Compression Cycling” at the beginning of the nineteenth century (1805). He also developed the first detailed and theoretically coherent design for a vapor-compression refrigerator, which identified all the major components (e.g., compressor and condenser, cooling coil, expander, evaporator) of a refrigeration cycle. The vapor-compression refrigerator uses a circulating refrigerant as the medium (usually a hot, saturated vapor). The refrigerant is first compressed to a higher pressure (and higher temperature) and then passed through a condenser. The hot, compressed vapor is then cooled and condensed into a liquid phase by passing the compressed vapor through a coil or tubes that are cooled by flowing water or cool air. To complete the refrigeration cycle, the refrigerant vapor from the evaporator is routed back into the compressor.
John Gorrie (1803–1855) [4] further adapted the basic refrigeration concept and developed the first practically useful vapor-compression refrigerator capable of producing ice (it was one of the earliest “cryogen-free” refrigerators). He filed for a US patent with the title “Improved process for the artificial production of ice” on February 27, 1848, which was granted on May 6, 1851 as US Patent No. 8080.
The refrigerator was shown in the patent illustrations with ice collected in a wooden box near the top [5].
In his patent application, G...
