Abstract: A chiller for chilling a quantity of fluid in a vessel comprises an adsorbent for receiving and adsorbing under pressure a quantity of gas; sealing means for sealing adsorbed gas in said adsorbent and releasing means for releasing adsorbed gas from said adsorbent in a controlled manner such that the action of desorption causes a reduction in the temperature of the adsorbent and gas which acts to chill the fluid.

Abstract: A method is provided for treating sewage by introducing carbon dioxide and oxygen therein so that the carbon dioxide reduces the pH of the sewage to about pH5.0 or below and reduces the activity of bacteria therein such that the oxygen can oxygenate the sewage rather than be consumed by the bacteria. Generation of malodorous compounds is significantly reduced or prevented until the carbon dioxide is sufficiently dispersed so that the pH rises above about 5.0.

Abstract: A pressure vessel 1 forming part of a PSA plant contains a molecular sieve adsorbent. A plurality of thermocouples are located within the molecular sieve adsorbent such that one junction 8 of each thermocouple is positioned adjacent the feed gas inlet 2 of the vessel 1 while the second junction 10 of each thermocouple is positioned adjacent the product gas outlet 4 of the vessel.

Abstract: An improved apparatus for the introduction of a gas into a liquid comprising a mixing device formed by a first generally convergent section and a second generally divergent section, said first section having a narrow outlet end of smaller diameter than an inlet end of said second section and extending thereinto so as to form an annular gap therebetween, and supply means for supplying said gas to said annular gap so as to facilitate the mixing of said gas with any liquid passing therethrough. The mixing device is preferably positioned at or near the surface of the liquid so as to avoid problems associated with hydrostatic head. The apparatus is advantageous in the treatment of a liquid with oxygen which is preferably generated by a Pressure Swing Adsorption device.

Abstract: A method and apparatus suitable for sweetening sewerage which avoids the need for pumping the sewerage. The method comprises the steps of passing the sewerage under a gas-tight enclosure and causing it to fall as a stream through a first passageway, passing bubbles of a gas, such as oxygen, up through the descending sewerage to dissolve in the liquid stream to form a gas-liquid stream and causing the gas-liquid stream to ascend through a second passageway in which further bubbles of the gas are passed therethrough to dissolve further gas in the stream to balance the liquid density in the descending and ascending streams.

Abstract: A method of treating a material with ozone including the steps of passing oxygen rich gas from a PSA plant 2 through an ozonizer 4 and then passing the ozonized oxygen thus formed directly back to the PSA plant where the ozone is adsorbed in a bed of silica gel contained within a vessel. During the desorption step nitrogen adsorbed in a bed of zeolite also located in the vessel desorbs the ozone from the bed of silica gel and a nitrogen-ozone gas leaves the PSA plant via a line in the feed end. The material is treated with the nitrogen-ozone gas.

Abstract: Air is separated in a vessel housing gas separation membranes. A flow control valve controls the passage of air to an inlet header of the vessel. The setting of the valve is adjusted in accordance with the level of oxygen impurity in product nitrogen leaving the vessel for an outlet header. A second flow control valve is provided and is of a kind whereby product nitrogen is able to be delivered at a constant flow rate over a range of different pressures upstream thereof. Accordingly, the apparatus is able to deliver nitrogen at a desired purity and flow rate.

Abstract: A system for controlling the atmosphere of a container for use in the storage and/or transportation of perishable goods which includes adsorption apparatus for the selective adsorption in whole or in part and in a predeterminded order of any water vapor, carbon dioxide, oxygen or ethylene contained within the atmosphere, a blower for urging the atmosphere to the adsorption apparatus, and a conduiting for returning the controlled atmosphere to the container.

Abstract: A refrigerator includes a cylinder containing a bed of adsorbent material and a gas, e.g. carbon dioxide. A piston compresses the gas which is adsorbed by the adsorbent material and the heat of adsorption is dissipated by fins to atmosphere. The piston, when retracted, decompresses the gas which desorbs from the adsorbent material. Repeated compression and decompression of the gas causes a cold zone to be created within the material which is thermally linked to a location to be refrigerated.

Abstract: A pressure swing adsorption plant for the separation of gas mixtures includes at least one pressure vessel containing an adsorbent bed that is able preferentially to adsorb at least one component of the gas mixture. The pressure vessel has an inlet at its top for the feed gas mixture, an outlet at its bottom for non-adsorbed gas and at least one heat conductive member containing a liquid medium arranged within the bed such that, in operation, heat is able to be conducted by convection through the liquid from a region of maximum temperature at or near the bottom of the bed to a region of minimum temperature at or near the top of the bed.

Abstract: A method of compressing oxygen includes passing the oxygen into a vessel 12 containing finely divided material. Next a driving gas, for example, air is compressed to a greater pressure than the oxygen and passed through the vessel 12 and the bed of material contained therein which creates a plug flow effect such that the oxygen is compressed by the air substantially without back-mixing.

Abstract: A process vessel has side walls of concrete which are lined with a gas and moisture-impermeable material to prevent:a) the egress of gas from the interior of the vessel; andb) ingress of moisture through the concrete into the interior of the vessel.

Abstract: A pipeline has an inner surface which comes into contact with cryogenic fluid at a temperature of 70.degree. K. The outer surface of the pipeline carries a coating of foamed polyurethane having closed cells containing carbon dioxide. The pipeline is located in an outer sleeve. The annular space defined between the pipe and the sleeve is filled with perlite powder and is able to be purged with dry nitrogen gas.In operation with the inner surface of the pipelines subjected to a temperature of 70.degree. K., the carbon dioxide in the cells of the polyurethane solidifies creating a vacuum therein. This increases the temperature difference across the polyurethane coating and enables the perlite powder to be maintained at a temperature above 77.degree. K. so that the nitrogen purgant does not condense. A relatively simple alternative to conventional vacuum insulation is thereby provided.

Abstract: A membrane gas separation apparatus, typically for separating air, includes a gas separation cell containing an array of membranes in the form of hollow fibres. The cell has a first gas port and a second gas port. Flow of gas to and from the ports is controlled by a four-port, two-position valve. In one position, the valve admits incoming air to the first port and allows product nitrogen to flow out of the second port. In the other position the roles of the ports are reversed and hence the direction of flow of the gas is reversed. During prolonged operation, there is a tendency for contaminants to affect disproportionately the feed gas inlet of the membrane fibres. By periodically changing the position of the valve, different ends of the membrane fibres are presented to the feed gas, and thus the operating life of the membranes is lengthened.

Abstract: A gas treatment or separation apparatus includes a vessel (2) containing a bed (18) of particulate material. Within the bed (18) there is located a plurality of distensible hollow members (30) each capable of being placed in communication with a source of fluid under pressure. The members (30) restrain movement of the particulate material.

Abstract: In a membrane apparatus for separating a gas mixture, permeate gas is withdrawn from the vessel housing the membranes along passages whose extent along the flow path of the nonpermeate gas is only a fraction of the extent of such flow path. Thus, the gas mixture to be separated may be passed along the insides of a multiplicity of hollow fibres 8 whose walls are of a suitable membrane and cells 18 for the withdrawal of the permeate gas are defined by partitions 16 extending transversely to the fibres 8. Alternatively, an open-pored foamed plastics may be used instead of the partitions 16, or the gas may pass outside the fibres which are arranged transversely to the general direction of gas flow through the vessel, the permeate gas being withdrawn along the inside of each hollow fibre.

Abstract: A refrigerated container 2 has associated therewith a compressor 6 which receives filtered air and passes it to a small apparatus 12 for separating air by pressure swing adsorption or by different rates of permeation of gas through semi-permeable membranes. Resulting air depleted in oxygen and water vapor flows into the interior of the container 2 and displaces atmosphere from the container 2 through a vent tube 20. Reducing the oxygen and water vapor content of the atmosphere in the container 2 (which may be a refrigerator or freezer) helps to preserve food stored therein and reduces the deposition of water or ice.

Abstract: A method and apparatus for the separation of air by pressure swing adsorption utilizing two beds of adsorbent material which are operated out of phase, thereby providing a more or less continuous flow of product oxygen with reduced argon content. A first adsorbent bed comprises a carbon molecular sieve which adsorbs oxygen more rapidly then nitrogen. The adsorbed oxygen is desorbed from the first bed and flows to a second bed, comprising a zeolite molecular sieve that adsorbs nitrogen preferentially to oxygen, thereby producing product oxygen as the non-adsorbed gas. Alternatively, the second bed comprises a carbon molecular sieve, and the adsorbed oxygen is desorbed as the oxygen product gas.

Abstract: A method and apparatus is disclosed in the separation of a gaseous mixture by pressure swing adsorption utilizing two beds of adsorptive material which are operated out of phase in the cycle thereby providing a more-or-less continuous flow of product. Each adsorbent bed contains a heat exchange chamber holding a volatile liquid. The liquid gives up vapor in the bed undergoing adsorption and condenses in the bed undergoing desorption. Heat is thereby transferred between the beds, thus improving the efficiency of each stage by retaining heat which would otherwise be lost.

Abstract: Fuel gas (typically taken from a source of natural gas associated with oil deposits) is burnt with air in a turbine 2 to produce a gaseous mixture comprising nitrogen, combustion products and oxygen. The mixture cotnains less than 20% by volume of oxygen. The mixture is cooled in a cooler 4 by heat exchange with water and then compressed in a compressor 6 which is driven by the turbine 2. The compressed gaseous mixture is separated typically by pressure swing adsorption to produce a gaseous nitrogen product suitable for use in the enhanced recovery of oil.