Refrigeration – Processes – Fluid external of refrigeration producing cycle
Reexamination Certificate
2002-03-27
2004-06-01
Paik, Sang Y. (Department: 3744)
Refrigeration
Processes
Fluid external of refrigeration producing cycle
C062S114000, C062S185000, C252S067000
Reexamination Certificate
active
06742345
ABSTRACT:
The present invention relates to temperature control systems and, more particularly, to a multi-stage commercial refrigeration system.
BACKGROUND OF THE INVENTION
Glycol-based fluids are commonly employed as coolant fluids. The formulations used are typically based on alkylene glycols such as ethylene and propylene glycol. However, problems exist with the use of these compounds as coolant fluids in certain applications. One use of such compounds is in commercial refrigeration systems. At temperatures approaching −40° F., the viscosity of propylene glycol compounds increases to the point where their use becomes impractical in commercial refrigeration systems charged with maintaining very low temperatures in product zones of the refrigeration units. This causes high pressure drop, low mechanical efficiency and high power consumption in the refrigeration system. In addition, ethylene glycol compounds are toxic. This causes concerns with regard to piping system integrity and problems with regard to detecting, repairing and cleaning up system leaks, changing of the refrigerant and disposal of the used refrigerant.
In view of the above, a requirement exists for a non-toxic heat transfer fluid having a viscosity low enough at temperatures down to approximately −40° F. to be used as a coolant fluid. A need also exists for a system which utilizes such a working fluid.
REFERENCES:
patent: 1213368 (1917-01-01), Hibbert
patent: 1696642 (1928-12-01), Massa
patent: 1820085 (1931-08-01), Moormann
patent: 1914222 (1933-06-01), Taylor
patent: 2003429 (1935-06-01), Cox
patent: 2087098 (1937-07-01), Spiegler et al.
patent: 2094564 (1937-09-01), Schenck et al.
patent: 2226487 (1940-12-01), Zink
patent: 2229215 (1941-01-01), Magruder, Jr. et al.
patent: 2369435 (1945-02-01), Coghill et al.
patent: 2378087 (1945-06-01), Kearney
patent: 2462694 (1949-02-01), Walker
patent: 2525478 (1950-10-01), Cunningham
patent: 3609087 (1971-09-01), Chi et al.
patent: 3630914 (1971-12-01), Nankee et al.
patent: 3809152 (1974-05-01), Boehmer
patent: 3960740 (1976-06-01), Truett
patent: 4184537 (1980-01-01), Sauder
patent: 4224801 (1980-09-01), Tyree, Jr.
patent: 4249388 (1981-02-01), Burns
patent: 4606837 (1986-08-01), McEntire et al.
patent: 4974419 (1990-12-01), Sabin et al.
patent: 5071582 (1991-12-01), Conville et al.
patent: 5118434 (1992-06-01), Meyer et al.
patent: 5202044 (1993-04-01), Hagihara et al.
patent: 5387360 (1995-02-01), Uekusa et al.
patent: 5394936 (1995-03-01), Budelman
patent: 5435379 (1995-07-01), Moslehi et al.
patent: 5470497 (1995-11-01), Schlosberg et al.
patent: 5494597 (1996-02-01), Krevalis et al.
patent: 5531078 (1996-07-01), Day et al.
patent: 5651257 (1997-07-01), Kasahara et al.
patent: 5688433 (1997-11-01), Kasahara et al.
patent: 5727393 (1998-03-01), Mahmoudzadeh
patent: 5921096 (1999-07-01), Warren
patent: 5974816 (1999-11-01), Endo
patent: 6018961 (2000-02-01), Venture et al.
patent: 6093341 (2000-07-01), Minks et al.
patent: 6145333 (2000-11-01), Richmond et al.
patent: 6415614 (2002-07-01), Greenfield et al.
patent: 544081 (1957-07-01), None
patent: 716052 (1965-08-01), None
patent: 352311 (1931-07-01), None
patent: 384089 (1932-12-01), None
patent: 59-091188 (1982-11-01), None
patent: 60-060178 (1983-09-01), None
Shell Chemicals, Viscosity of PDO and MPG Water Solutions, Apr. 9, 1999.*
Edward Eaton, A Chemical Base for Engine Coolant/Antifreeze with improved Thermal Stability Properties, Mar. 5-8, 2001, SAE, 2001-01-1182.*
L.P. Polderman; The Physical Properties and Behavior of Ethylene and Propylene Glycol and Their Water Mixtures (Article); Jan. 26-29, 1959, Philadelphia, Pennsylvania; pp 1-15.
Edward R. Eaton, W.H. Boon and Chris J. Smith; A Chemical Base for Engine Coolant/Antifreeze with Improved Thermal Stability Properties (Article); Mar. 5-8, 2001; Detroit, Michigan; pp. 1-9.
Shell Chemicals website materials (www.shellchemicals.com) relating to 1,3-propanediol applications and chemical properties; What is 1,3-propanediol (PDO)? (Article); 2001.
S.B. Park, J.W. Lee and H. Lee; Surface Tensions and Thermal Conductivities of Aqueous LiBr-Based Solutions Containing n-Octanol and 2-Ethyl-1-Hexanol; Application to Absorption Heat Pump (Article); Jun. 25-30, Boulder, Colorado; pp. 1-22.
Viscosity of PDO Solutions (Graph).
Shell Chemicals; 1,3-Propanediol; specification sheet; Apr. 2000, 1 double-sided sheet.
Shell Chemicals; Viscosity of PDO and MPG Water Solutions; 1 sheet.
Pro KUHLSOLE GmbH; PEKASOL 50 Special Cooling Medium; 8 double-sided sheets.
Hydrol Chemicals; “do you want the best secondary refrigerant?”; brochure; 1997; 4 sheets.
Glycol data; 5 sheets.
Shell Chemicals; 1,3-Propanediol (PDO) Background; Apr. 9, 1999; 15 sheets.
Paik Sang Y.
Ring Thomas J.
The Penray Companies, Inc.
Wildman Harrold Allen & Dixon LLP
Zec Filip
LandOfFree
Temperature control system using aqueous 1,3-propanediol... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Temperature control system using aqueous 1,3-propanediol..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Temperature control system using aqueous 1,3-propanediol... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3363020