GB1156698A - Improvements in or relating to a Method and Apparatus for Determining and Controlling the Degree of Saturation of Adsorbents. - Google Patents

Abstract

1,156,698. Measuring moisture content electrically. VEREINIGTE OSTERREICHISCHE EISEN-UND STAHLWERKE A.G. Aug. 26, 1966 [Sept. 17, 1965], No. 38466/66. Heading G1N. In an air dehumidifier 1, Fig. 1, the degree of saturation of an adsorptive gel through which the air passes is measured in terms of the difference in temperatures between the inlet 2 and a region 4' inside the dehumidifier, as measured by thermocouples 5, 6. The adsorption of moisture by the gel causes heat to be released, thereby raising the temperature of the outlet gas. When the gel is dried by a regenerating gas, heat is absorbed and the thermocouples indicate when drying is complete. The zone of the gel in which dehumidification takes place moves progressively through the gel in the direction of air-flow as the gel becomes exhausted, and the movement of this zone is detected by placing a plurality of differential thermocouples with one junction (5, Fig. 2, not shown) of each at the inlet 2, and the other junctions at spaced points (6, 6a, 6b) in the dehumidifier column (1). Each differential thermocouple is connected to a respective amplifier (12, 12a, 12b) which operates a respective lamp (13, 13a, 13b) to indicate degree of saturation of the gel. The output signals (21, Fig. 3, not shown) of differential thermocouples (5, 6) may be used, alternatively, to operate air-flow gates (15, 16) so as to switch the air to be dried (17) from one dehumidifier column (1a) to a second column (1) upon complete saturation of the gel in the first column (1a). At the same time regenerating gas (18) is switched from the second column (1) to the first column (1a) to restore the gel.