591.    ---------------.[COKE AND GAS.]  Linde-Fränkl Process for Oxygen Separation.  Vol. 9, 1947, pp. 236-240.

      Theory of air liquefaction is discussed and practical operating results are shown.  A list of 73 units built between 1930 and 1941 is given.  The working of the process is explained in some detail, and power requirements are calculated.  Installation costs for early-war German conditions are given as RM 500,000/1,000 m.³ of O₂/hour (English conversion rate RM 10 to 1 pound).  Operating costs were divided for production up to 2,000 m.³/hr. into power 40%, amortization and 5%, interest 40%, and labor and material costs 20%.  Above 2,000 m.³/hour the division was 50%, 40%, and 10%.  In the plants with an hourly capacity of 1,000-2,000 m.³ of O₂, the total cost of the gas was calculated to be 2.2-2.5 Rpfg./m.³ at 0° and 760 mm.; in a 3,000-m.³ plant the cost should fall to 1.5 Rpfg./m.³  A fair average cost figure/m.³ of 98% O₂ with power at 1.5 Rpfg./kw.-hr. would be 2.5 Rpfg.  Converted into English equivalents, 98% O₂ would cost 17 d./1,000 cu. ft. with power at 0.36 k./kw.-hr.