A process is disclosed for increasing hydrogen recovery in an integrated refinery and petrochemical complex in which natural gas is used as a co-purge gas in a pressure swing adsorption unit. This natural gas is recovered in tail gas from the pressure swing adsorption unit. This process is useful for refinery off-gas and partial oxidation feeds.

Disclosed herein are multi-bed rapid cycle pressure swing adsorption (RCPSA) processes for separating O.sub.2 from N.sub.2 and/or Ar, wherein the process utilizes at least five adsorption beds each comprising a kinetically selective adsorbent for O.sub.2 having an O.sub.2 adsorption rate (1/s) of at least 0.20 as determined by linear driving force model at 1 atma and 86 F.

Systems and methods are provided for operating a combined cycle power plant while enhancing the CO.sub.2 content of the flue gas generated by the power plant. The CO.sub.2 content is enhanced by using a combination of exhaust gas recycle and oxygen-enriched combustion. The oxygen-containing flow for performing the oxygen-enriched combustion can be generated by an integrated pressure swing adsorption process that allows for production of a commercial grade nitrogen stream (95 vol % or more of N.sub.2) while also providing an oxygen-containing stream with an oxygen content between 25 vol % and 48 vol % with high 02 recovery.

Provided is a pressure swing adsorption type hydrogen manufacturing apparatus that can improve the product recovery rate in a state where the purity of the product is kept from being reduced. A process control unit P controls operation of adsorption towers 1 that generate a product gas by adsorbing, using adsorbents, adsorption target components other than hydrogen components from a source gas, in a state where an adsorption process, a pressure-equalization discharge process, a desorption process, and a pressure-restoration process are successively repeated. The process control unit is configured to control operation of the adsorption towers 1 in such a manner that a prior pressure-equalization process of supplying gas inside an adsorption tower 1 undergoing the pressure-equalization discharge process to an adsorption tower 1 undergoing the pressure-restoration process is performed in an initial stage of a unit processing period, a subsequent pressure-equalization process of supplying gas inside the adsorption tower 1 undergoing the pressure-equalization discharge process to an adsorption tower 1 undergoing the desorption process is performed in a final stage of the unit processing period, a pressurization process of introducing a product gas H to perform pressurization is performed, as the pressure-restoration process, subsequently to the prior pressure-equalization process, and the pressurization process is performed while overlapping with the subsequent pressure-equalization process.

Disclosed herein are multi-bed rapid cycle pressure swing adsorption (RCPSA) processes for separating O.sub.2 from N.sub.2 and/or Ar, wherein the process utilizes at least five adsorption beds each comprising a kinetically selective adsorbent for O.sub.2 having an O.sub.2 adsorption rate (1/s) of at least 0.20 as determined by linear driving force model at 1 atma and 86 F.

The present disclosure relates to a pressure swing adsorption apparatus for hydrogen purification from decomposed ammonia gas and a hydrogen purification method using the same, and more particularly, the pressure swing adsorption apparatus of the present disclosure includes a plurality of adsorption towers including a pretreatment unit and a hydrogen purification unit wherein the adsorption towers of the pretreatment unit and the hydrogen purification unit are packed with different adsorbents, thereby achieving high purity hydrogen purification from mixed hydrogen gas produced after ammonia decomposition, making it easy to replace the adsorbent for ammonia removal, minimizing the likelihood that the lifetime of the adsorbent in the hydrogen purification unit is drastically reduced by a very small amount of ammonia, and actively responding to a large change in ammonia concentration in the raw material.

Additionally, a hydrogen purification method using the pressure swing adsorption apparatus of the present disclosure physically adsorbs and removes impurities such as moisture (H.sub.2O), ammonia (NH.sub.3) and nitrogen (N.sub.2) included in mixed hydrogen gas produced after ammonia decomposition below extremely small amounts, thereby achieving high purity hydrogen purification with improved selective adsorption of moisture, ammonia and nitrogen and maximized hydrogen recovery rate and productivity. In addition, since the temperature swing adsorption process is not introduced, there is no need for a heat source for regeneration, thereby reducing the driving cost.

An improved DAC unit and process containing an adsorber structure comprising an array of adsorber elements with a support layer and on both sides thereof at least one sorbent layer and at least one protective layer comprising a microporous material disposed around the support layer and the sorbent layer, wherein the protective layer has greater hydrophobicity than the sorbent material, wherein the adsorber elements are parallel to each other and spaced apart forming parallel fluid passages for flow-through of ambient atmospheric air and/or desorbing media, the method comprising the following sequential and repeating steps: (a) adsorption by flow-through; (b) isolating said sorbent; (c) injecting a stream of desorbing media through said parallel fluid passages and inducing an increase of the temperature; (d) extracting desorbed carbon dioxide from the unit and separating it from desorbing media; (e) bringing the sorbent material to ambient temperature conditions.

In various aspects, methods are provided for hydrogen production while reducing and/or mitigating emissions during various refinery processes that produce syngas, such as power generation. Syngas can be effectively separated to generate high purity carbon dioxide and hydrogen streams, while reducing and/or minimizing the energy required for the separation, and without needing to reduce the temperature of the flue gas. In various aspects, the operating conditions, such as high temperature, mixed metal oxide adsorbents, and cycle variations, for a pressure swing adsorption reactor can be selected to minimize energy penalties while still effectively capturing the CO.sub.2 present in syngas.

A process is disclosed for increasing hydrogen recovery in an integrated refinery and petrochemical complex in which natural gas is used as a co-purge gas in a pressure swing adsorption unit. This natural gas is recovered in tail gas from the pressure swing adsorption unit. This process is useful for refinery off-gas and partial oxidation feeds.

The present invention provides a refrigerating and freezing device. A first sealed space and a second sealed space are disposed in a storage space inside the refrigerating and freezing device. The refrigerating and freezing device is further provided with a nitrogen generation device, which comprises an adsorption device and an air compressor that supplies compressed air for the adsorption device. The adsorption device utilizes the compressed air to prepare nitrogen that is provided for the first sealed space and an oxygen-enriched gas that is provided for the second sealed space. The freshness preservation capability of the first sealed space is improved. The bioactivity of food in the second sealed space is guaranteed.