Abstract: A method of making a metal foam object includes the steps of mixing a gasifier with metal powder and subjecting the mixture to an elevated temperature T1 and pressure P1 to form a sintered sheet; placing at least a portion of the sintered sheet into a mold and subjecting the mold to a temperature T2 where T2 is greater than T1 at which the metal melts and the gas is released from the gasifier; quenching the metal foam object thus formed in the mold; and passing a hot inert gas through the metal foam object.

Abstract: A modular adsorption plant comprises one or more transportable cargo containers which hold the various adsorbent beds, pumping apparatus and so on which comprise the plant. The containers are easily transportable, and may be rapidly assembled in modular fashion to produce a large capacity plant.

Abstract: A method of combustion and an apparatus therefor in which separate streams of very lean and very rich fuel/oxidant mixture are combusted separately, the products of combustion therefrom being thoroughly mixed before final combustion takes place. The lean/rich primary combustion minimizes combustion temperatures and pollutant formation, whilst the final combustion is substantially stoichiometric.

Abstract: An apparatus for refrigerating goods in a container storing a cryogenic fluid and means for discharging the fluid into the container in order to reduce the temperature therein, characterized in that the storing means is adapted to operate at atmospheric pressures but not at pressures substantially greater than atmospheric. Such a system provides a single and inexpensive means for refrigerating goods in a transportable container, which may be divisible into smaller compartments, and may also be provided with eutectic plates to act as a thermal “buffer” whenever the container/a compartment is opened for loading/unloading.

Abstract: A container for cooling/refrigerating produce comprising at least one panel made from metal foam for storing a cryogenic fluid under pressure and means for discharging said fluid into the container in order to reduce/maintain the temperature within the container.

Abstract: A method for treating a gas stream containing one or more perfluoro-organic compounds to remove the perfluoro-organic compound(s) therefrom, which comprises bringing the gas stream in to contact with an alkali metal fluoride in the presence of carbon and water vapor at a temperature of 350° C. to 1000°C.

Abstract: A brazing method for joining to or more pieces of metal together includes running a molten brazing solder into a space between the pieces, heating at least the adjacent surfaces of the pieces to be joined to brazing temperature in a reducing atmosphere and preheating at least the adjacent surfaces to about 600° C. in an oxidizing atmosphere prior to said heating to the brazing temperature.

Abstract: A compound vacuum pump includes a pump body divided by a partition into upper and lower chambers. A screw pump section occupies the lower chamber and a Roots-type pump section occupies the upper chamber. The Roots-type pump section comprises two rotors each with a disc for rotation in a bore of the partition.

Abstract: A vacuum pump for pumping gas from a pump inlet to a pump outlet, comprising a rotor and a stator body in which the rotor is adapted for rotation and including at least two molecular drag stages each comprising adjacent stationary and rotating Holweck cylinders attached to the stator body and the rotor respectively and with a threaded upstanding helical flange positioned therebetween which is attached either to the stationary or to the rotating cylinder wherein the molecular drag stage closest to the pump inlet has the threaded flange on its rotating cylinder and the subsequent molecular drag stage or stages has the threaded flange on the stationary cylinder.

Abstract: A vacuum pump comprising a shaft rotatable by means of a motor, at least two spaced pump stages mounted on the shaft, a first pump inlet through which gas can pass for passage through all the pump stages for evacuating a first system and a second pump inlet through which gas can enter the pump at an inter-stage location for passage through only subsequent stages of the pump for evacuating a second system, said first and second systems each having a gas outlet flange for attachment to a first or a second pump inlet, in which the vacuum pump is mounted relative to the respective first and second systems such that the longitudinal axis of the shaft is inclined to each of the gas outlet flanges.

Abstract: A valve for use with an ultra high purity gas comprising a valve body defining a valve chamber having a valve outlet through which gas is discharged and containing a reciprocable sealing member, characterized in that the valve chamber is in fluid communication with a source of the gas and in that the sealing member is reciprocable along an axis substantially parallel to the direction of flow of gas discharged from the valve outlet and into and out of sealing contact with a sealing face located within the valve chamber and circumscribing the inlet end of a valve outlet pipe, the opposite, outlet end of which pipe forms the valve outlet. The valve has a low wetted area and is thus easy to purge, and the valve design both reduces wear and restricts it to a single component which is easily replaced when necessary.

Abstract: A process for the abatement of trimethylvinylsilane (TMVS) by contacting a gas stream containing TMVS with copper(II) oxide (CuO) and/or manganese oxide (MnO2) in the presence of sufficient oxygen to prevent reduction of the oxides and at a temperature of at least room temperature, but preferably, at an elevated temperature greater than 100° C.

Abstract: Sulfur vapor is formed by partial oxidation of hydrogen sulphide. A burner is operated so as to establish a flame in a furnace in or into which the burner fires. There is supplied to the flame from the first region of the mouth of the burner at least one flow of a first combustible gas comprising hydrogen sulfide. At least one second flow of a first oxidizing gas is caused to issue from the mouth of the burner and mix in the flame with the first combustible gas. There is supplied to the flame from a second region of the mouth of the burner surrounding and spaced from the said first region at least one third flow of a second combustible gas comprising hydrogen sulfide. At least one fourth flow of a second oxidizing gas is caused to issue from a region or regions of the mouth of the burner surrounded by said second region and mix in the flame with the second combustible gas. At least one fifth, outermost flow of a third oxidizing gas is caused to mix in the flame with the second combustible gas.

Abstract: Apparatus for recovering sulphur from a combustible gas stream comprising hydrogen sulphide is provided. The combustible gas stream, air and oxygen, or an oxygen-rich stream, are fed via a coaxial burner into an elongate furnace thereby creating a longitudinally-extending flame which has one or more relatively oxygen-rich, intense, combustion regions wherein hydrogen sulphide is combusted to form sulphur dioxide and one or more relatively oxygen-poor, endothermic, thermal dissociation regions. Residual hydrogen sulphide reacts with sulphur dioxide formed by the combustion to produce sulphur vapor. The apparatus includes a waste heat boiler to reduce the temperature of the furnace effluent and a condenser to remove sulphur therefrom. The furnace has an aspect ratio of about 8:1. The flame diverges from its root to occupy at its maximum cross-sectional area at least about 80% of the cross-sectional area of the furnace interior coplanar therewith.

Abstract: A first stream of air is compressed in a main air compressor and a booster compressor is cooled at a first pressure by passage through a main heat exchanger. The cooled stream is introduced without further compression into the higher pressure column of a double rectification column including in addition to the column a lower pressure column and a condenser-reboiler. A second stream of compressed air is expanded from a second pressure in an expansion turbine with the performance of external work. The expanded second stream of air is introduced into the lower pressure column. An oxygen product, typically impure, is taken from the bottom region of the lower pressure column. The second pressure is less than the first pressure column. The second pressure is less than the first pressure, the second air stream being taken from intermediate the compressors.

Abstract: A double column air separation method in which a first stream of compressed air is cooled by passage through a main heat exchanger from its warm end countercurrently to a nitrogen stream withdrawn from the top of a lower pressure rectification column. The first stream of compressed air flows from the main heat exchanger into a higher pressure rectification column through an inlet. A second stream of compressed air is also passed into the warm end of the main heat exchanger and is cooled therein. The second stream of compressed air passes out of heat exchange with the nitrogen stream at a temperature lower than the exit temperature therefrom of the first stream of compressed air and at least 5K lower than the bubble point temperature of air at the pressure prevailing at the inlet. A stream of oxygen-enriched liquid passes isenthalpically from the bottom of the higher pressure column to the lower pressure column.

Abstract: A first combustible gas stream containing hydrogen sulphide is subjected to treatment in a first Claus plant including a first thermal Claus stage. Part of the hydrogen sulphide content of a second combustible gas stream containing hydrogen sulphide is burned in at least one further thermal Claus stage. The combustion in the further thermal Clause stage is supported by oxygen-enriched air having an oxygen mole fraction of at least about 0.25 or by oxygen. Resulting sulphur dioxide in the further thermal Clause stage reacts with residual hydrogen sulphide to form sulphur vapour which is condensed out of the effluent gas from the further thermal Claus stage to form a sulphur-depleted effluent gas stream. A first control signal is generated which is a function of the flow rate of the second gas. A second control signal which is a function of the hydrogen sulphide/sulphur dioxide mole ratio in the sulphur-depleted effluent stream is also generated.

Abstract: A multi-bed PSA pressure vessel includes a hollow tubular body having one or more end plates releasably secured thereto. Secured to the end plate(s) are pipes which extend along the interior of the hollow tubular body. Each of the pipes terminates at a location along the length of the tubular body different from the remaining pipes. In a preferred embodiment, a plurality of perforated spacing flanges are secured to the pipe and some adjacent flanges defining between them a space for receiving adsorbing sieve material.

Abstract: Nitrogen is produced by separation of it from air. Nitrogen so separated is condensed. Most or all of the nitrogen is separated by rectification. At least some of the condensed nitrogen is employed as reflux in the rectification. The nitrogen is both separated and condensed at three or more different pressures.

Abstract: Air is separated in a double rectification column comprising a higher pressure column and a lower pressure column, the latter operating at pressures of less than 2 bar absolute. An oxygen product is withdrawn from the column by a pump. A first vaporous nitrogen stream is taken from the top of the higher pressure column, is compressed in a compressor and is used in a gas turbine. Feed to the lower pressure column is derived from a stream of the bottom oxygen-enriched liquid fraction obtained in the higher pressure column. To this end, this stream is subjected to further separation (typically in further rectification column) to form a vaporous nitrogen fraction (a flow of which is condensed and is used as reflux in the lower pressure column) and an oxygen-containing feed to the lower pressure column which flows via an outlet and a condenser to the column. At least 60% of the nitrogen product flowing to the gas turbine is taken from the higher pressure column.