Abstract: Method for recovering a desired component from a waste gas comprising (a) at an operating facility, introducing a waste gas comprising the desired component and one or more undesired components into an adsorber containing adsorbent material selective for the desired component, adsorbing at least a portion of the desired component therein, (b) terminating flow of waste gas into the adsorber; and (c) recovering and concentrating the desired component by either (1) isolating the adsorber, transporting the adsorber to a central processing facility, or (2) withdrawing from the adsorber an intermediate gas enriched in the desired component, compressing the intermediate gas and storing it in a vessel, isolating the vessel, transporting the vessel to a central processing facility to provide a concentrated product further enriched in the desired component.

Abstract: The present invention discloses the improvements to a vacuum swing adsorption (VSA) process used for Xe recovery. By only collecting the recovered gas mixture after the initial evacuation of N2 from the adsorbent vessel and void space, the recovered Xe is not diluted by N2 contained in the adsorbent vessel and void space. The concentration of the recovered Xe can by increased (high purity), simultaneously little Xenon is lost. During the initial evacuation of N2, the vessel has been evacuated to a pressure less than 1 atmospheric pressure, for example, from 100 to 1 torr.

Abstract: Method for recovering a desired component from a waste gas comprising (a) at an operating facility, introducing a waste gas comprising the desired component and one or more undesired components into an adsorber containing adsorbent material selective for the desired component, adsorbing at least a portion of the desired component therein, (b) terminating flow of waste gas into the adsorber; and (c) recovering and concentrating the desired component by either (1) isolating the adsorber, transporting the adsorber to a central processing facility, or (2) withdrawing from the adsorber an intermediate gas enriched in the desired component, compressing the intermediate gas and storing it in a vessel, isolating the vessel, transporting the vessel to a central processing facility to provide a concentrated product further enriched in the desired component.

Abstract: Systems of checking thermal-induced circulation of a coolant in a fuel cell stack are disclosed. The system includes coolant inlet and outlet lines extending from a fuel cell stack. A pump and a radiator are confluently connected to the coolant inlet and coolant outlet lines. In one embodiment, a valve (either check type or automatic type) is provided in the coolant outlet line at the bottom of the fuel cell stack to prevent the flow of cold coolant from the coolant outlet line into the fuel cell stack upon start-up of the fuel cell stack. In another embodiment, a valve (either one-way flow control type or automatic type) is provided in the coolant inlet line at the top of the fuel cell stack. A method of checking thermal-induced circulation of a coolant in a fuel cell stack is also disclosed.

Abstract: The present invention discloses the improvements to a vacuum swing adsorption (VSA) process used for Xe recovery. By only collecting the recovered gas mixture after the initial evacuation of N2 from the adsorbent vessel and void space, the recovered Xe is not diluted by N2 contained in the adsorbent vessel and void space. The concentration of the recovered Xe can by increased (high purity), simultaneously little Xenon is lost. During the initial evacuation of N2, the vessel has been evacuated to a pressure less than 1 atmospheric pressure, for example, from 100 to 1 torr.

Abstract: An internal coolant circulation system and method of homogenizing waste heat in a fuel cell stack using homogenous thermal coolant cycling is disclosed. The method includes operating a fuel cell stack, distributing a coolant through the fuel cell stack, terminating operation of the fuel cell stack, retaining the coolant in the fuel cell stack and circulating the coolant throughout the fuel cell stack.

Abstract: Systems of checking thermal-induced circulation of a coolant in a fuel cell stack are disclosed. The system includes coolant inlet and outlet lines extending from a fuel cell stack. A pump and a radiator are confluently connected to the coolant inlet and coolant outlet lines. In one embodiment, a valve (either check type or automatic type) is provided in the coolant outlet line at the bottom of the fuel cell stack to prevent the flow of cold coolant from the coolant outlet line into the fuel cell stack upon start-up of the fuel cell stack. In another embodiment, a valve (either one-way flow control type or automatic type) is provided in the coolant inlet line at the top of the fuel cell stack. A method of checking thermal-induced circulation of a coolant in a fuel cell stack is also disclosed.

Abstract: Systems of checking thermal-induced circulation of a coolant in a fuel cell stack are disclosed. The system includes coolant inlet and outlet lines extending from a fuel cell stack. A pump and a radiator are confluently connected to the coolant inlet and coolant outlet lines. In one embodiment, a valve (either check type or automatic type) is provided in the coolant outlet line at the bottom of the fuel cell stack to prevent the flow of cold coolant from the coolant outlet line into the fuel cell stack upon start-up of the fuel cell stack. In another embodiment, a valve (either one-way flow control type or automatic type) is provided in the coolant inlet line at the top of the fuel cell stack. A method of checking thermal-induced circulation of a coolant in a fuel cell stack is also disclosed.

Abstract: The invention provides vacuum swing adsorption processes that produce an essentially carbon monoxide-free hydrogen or helium gas stream from, respectively, a high-purity (e.g., pipeline grade) hydrogen or helium gas stream using one or two adsorber beds. By using physical adsorbents with high heats of nitrogen adsorption, intermediate heats of carbon monoxide adsorption, and low heats of hydrogen and helium adsorption, and by using vacuum purging and high feed stream pressures (e.g., pressures of as high as around 1,000 bar), pipeline grade hydrogen or helium can purified to produce essentially carbon monoxide -free hydrogen and helium, or carbon monoxide, nitrogen, and methane-free hydrogen and helium.

Abstract: A process and an apparatus for removal of radon from indoor air. The process having the step of contacting indoor air with an adsorbent, that is a silver-exchanged zeolite. The apparatus for the removal of radon from indoor air comprises a silver exchanged zeolite.

Abstract: A first aspect of a process of recovering xenon from feed gas includes: providing an adsorption vessel containing adsorbent having a Xe/N2 selectivity ratio <75; feeding into the adsorption vessel feed gas having an initial nitrogen concentration >50% and an initial xenon concentration ?0.5%; evacuating the adsorption vessel; and purging the adsorption vessel at a purge-to-feed ratio ?10. The final xenon concentration is ?15× the initial xenon concentration. A second aspect of the process includes providing an adsorption vessel containing adsorbent having a Xe Henry's law Constant ?50 mmole/g/atm; feeding into the adsorption vessel feed gas having an initial nitrogen concentration >50% and an initial xenon concentration ?0.5%; heating and purging the adsorption vessel to recover xenon having a final concentration ?15× its initial concentration. Apparatus for performing the process are also described.

Abstract: Systems of checking thermal-induced circulation of a coolant in a fuel cell stack are disclosed. The system includes coolant inlet and outlet lines extending from a fuel cell stack. A pump and a radiator are confluently connected to the coolant inlet and coolant outlet lines. In one embodiment, a valve (either check type or automatic type) is provided in the coolant outlet line at the bottom of the fuel cell stack to prevent the flow of cold coolant from the coolant outlet line into the fuel cell stack upon start-up of the fuel cell stack. In another embodiment, a valve (either one-way flow control type or automatic type) is provided in the coolant inlet line at the top of the fuel cell stack. A method of checking thermal-induced circulation of a coolant in a fuel cell stack is also disclosed.

Abstract: An internal coolant circulation system and method of homogenizing waste heat in a fuel cell stack using homogenous thermal coolant cycling is disclosed. The method includes operating a fuel cell stack, distributing a coolant through the fuel cell stack, terminating operation of the fuel cell stack, retaining the coolant in the fuel cell stack and circulating the coolant throughout the fuel cell stack.

Abstract: A fuel cell system that uses compressed and heated cathode input air to heat the fuel cell stack at system start-up. The system includes a heat exchanger that uses the system cooling fluid to cool the compressed and heated cathode input air before it is sent to the fuel cell stack. At system start-up, a proportional by-pass valve directs a controlled portion of the cooling fluid around the heat exchanger so that the heated cathode input air can be used to heat the fuel cell stack. Once the stack reaches its operating temperature, the by-pass valve does not by-pass the heat exchanger. The fuel cell system also includes an inlet air valve that is used to choke the compressor at system start-up to cause the compressor to rapidly heat the compressed air.

Abstract: Xenon and/or krypton are recovered from oxygen containing gas, typically derived from liquid oxygen bottoms in a cryogenic air separation plant, by selective adsorption on a Li and Ag exchange zeolite containing 5 to 40% Ag exchange capacity on an equivalents basis, with periodic thermal regeneration of the adsorbent.

Abstract: Xenon and/or krypton are recovered from oxygen containing gas, typically derived from liquid oxygen bottoms in a cryogenic air separation plant, by selective adsorption on a Li and Ag exchange zeolite containing 5 to 40% Ag exchange capacity on an equivalents basis, with periodic thermal regeneration of the adsorbent.

Abstract: An improved adsorption process is provided for purifying hydrogen from a feed gas mixture including hydrogen and at least one impurity selected from the group consisting of carbon monoxide and nitrogen. The process includes providing an adsorption apparatus having a discharge end adsorption layer containing an adsorbent with a Henry's law constant (KH) at 70° F. for the impurity from about 0.5 to about 2.4 mmole/g/atm. The product gas collected from the adsorption apparatus is high purity (99.99+%) hydrogen.

Abstract: The present invention provides a pressure swing adsorption process. The process includes providing a pressure swing adsorption apparatus having a discharge end adsorption layer of activated carbon, feeding through the apparatus a feed gas including hydrogen, carbon monoxide and at least one of argon and oxygen, and collecting a product gas from the apparatus, wherein the product gas is high purity hydrogen. Also provided is a method for decreasing an amount of impurities in a product gas from a pressure swing adsorption process for separating hydrogen from impurities including carbon monoxide, and at least one of argon and oxygen.

Abstract: The present invention is a process for adsorbing carbon dioxide from a carbon dioxide containing gas mixture comprising contacting the gas mixture with an activated carbon adsorbent having a density in the range of approximately 0.56 to 0.61 g/cc (35 to 38 lbs./ft.sup.3) and adsorbing the carbon dioxide on the activated carbon adsorbent.