Abstract: A multi-pass tubeside shell and tube heat exchanger comprises: a shell having flanged ends; a removable tube bundle having a fixed tubesheet at one end and a floating tube sheet at the opposite end; a false tube sheet bolted to the floating tubesheet and having a passage hole aligned with each tube in the floating tubesheet to direct the flow of tube fluid; and a bonnet having a flange bolted to the outer portion of the false tubesheet. The use of the false tubesheet and attachment of the bonnet to the outer portion thereof maximizes available tube space. With the removal of the bonnet, and the false tubesheet, the bundle can be conveniently removed.

Abstract: A wet surface air cooling system is disclosed and includes a primary cooling unit having a bundle of heat exchanger tubes. Water is directed over the bundle of heat exchanger tubes and is collected in a collection basin. A secondary cooling tower is provided and a closed circulatory loop draws a portion of the water from the collection basin and directs the water to the secondary cooling tower to increase the cooling capacity of the system. The secondary cooling tower is rendered operative automatically upon sensing a particular temperature of the water in the circulation system of the primary cooling unit.

Abstract: A method and apparatus are provided for adsorbing a first gas from a mixture thereof with a second gas, to reduce the concentration of the first gas in the mixture to below a desired maximum concentration, in which the adsorption cycle is timed according to the rate of fill through an orifice of a space of predetermined volume by withdrawing a portion of system gas, feeding such system gas portion into a space of predetermined volume through an adjustable orifice, accumulating the withdrawn system gas in the space, and discontinuing the adsorption cycle when the volume and/or pressure of accumulated system gas in the space reaches or exceeds a predetermined minimum, thereby making it possible to control the cycling independently of any external control or power source.

Abstract: An improved method and apparatus are provided for adsorbing water vapor from a mixture thereof with a second gas to reduce the water vapor concentration in the mixture to below a permissible maximum concentration, in which the advance of the leading edge of the moisture front in a sorbent bed is detected by sampling the gas sufficiently far from the end of the bed to prevent the moisture front from leaving the bed, using a gas sampling probe, so that when the moisture front reaches this point, the adsorption cycle is discontinued, and the bed regenerated; a failed or inoperative sensor or sensor circuit being detected by intoducing to the sensor wet air from the dryer inlet; in the absence of a response sensing the air as wet, an alarm is given, and optionally, the dryer can automatically be placed in a fixed-time cycle operation.