Abstract: A catalytic conversion process using a fluidized conversion zone, which requires a minimum superficial gas velocity to function properly, and a motor-driven, capacity-limited product compressor zone is started up using a thermal compressor by establishing two start-up gas recirculation circuits, one using the product compression zone running at high pressure to recirculate about 40 to 60 vol-% of the effluent gas stream from the conversion zone and the other running at low pressure and carrying the remaining portion of the effluent gas stream from the fluidized conversion zone where the high pressure circuit supplies motive gas to the thermal compression zone and the low pressure circuit supplies suction gas to the thermal compressor and the resulting compressed discharge gas enables the catalytic process to start up without the use of a dedicated motor-driven start-up compressor.

Abstract: An improved methanol-to-olefin (MTO) product recovery scheme is provided which enables substantial reduction in the amount of light olefins that are undesirably captured in a dimethylether (DME) recycle stream when a portion of the methanolic feed to the MTO reaction zone is used as the scrubbing solvent in a primary DME absorption zone in order to recycle this DME oxygenate by-product to the MTO reaction zone. In accordance with the present invention, a liquid solvent stream recovered from the primary DME absorption zone is subjected in a stripping zone to light olefin stripping conditions sufficient to lift a substantial portion of the light olefins that are absorbed in the DME solvent without stripping a significant portion of this methanol solvent, thereby increasing the recovery of desired light olefins while simultaneously diminishing the amount of light olefins carried by the DME recycle stream back to MTO conversion step.

Abstract: The invention is a process for recovering heat and removing impurities from a reactor effluent stream withdrawn from a fluidized exothermic reaction zone for conversion of oxygenates into light olefins from an oxygenate feedstream. The process comprises a two-stage quench tower system to remove water from the reactor effluent stream in the first tower and recover heat from the reactor effluent to at least partially vaporize the feedstream by indirect heat exchange between the oxygenate feedstream and either a first stage overhead stream or a first stage pumparound stream. A drag stream withdrawn from the first tower comprises the majority of the impurities and higher boiling oxygenates. The second stage tower further removes water and provides a purified water stream which requires minimal water stripping to produce a high purity water stream. The invention concentrates the impurities into a relatively small stream and results in significant energy and capital savings.

Abstract: A process is provided for the concentration and recovery of ethylene and heavier components from an oxygenate conversion process. A separation process such as a pressure swing adsorption (PSA) process is used to remove hydrogen and methane from a demethanizer overhead stream comprising hydrogen, methane and C2 hydrocarbons and subsequently return the recovered C2 hydrocarbons to be admixed with the effluent from the oxygenate conversion process. This integration of a separation zone with a fractionation scheme in an ethylene recovery scheme using an initial demethanizer zone resulted in significant capital and operating cost savings by the elimination of cryogenic ethylene-based refrigeration from the overall recovery scheme.

Abstract: The present invention relates to a process for the recovering heat and removing impurities from a reactor effluent stream withdrawn from a fluidized exothermic reaction zone for the conversion of oxygenates into light olefins from an oxygenate feedstream. The process comprises a novel two-stage quench tower system to remove water from the reactor effluent stream in the first tower and recover heat from the reactor effluent to at least partially vaporize the feedstream by indirect heat exchange between the oxygenate feedstream and either a first stage overhead stream or a first stage pumparound stream. A drag stream withdrawn from the first tower comprises the majority of the impurities and any higher boiling oxygenates. The second stage tower further removes water from the light olefin product stream and provides a purified water stream which requires only minimal water stripping to produce a high purity water stream.

Abstract: The present invention relates to an improvement of integrated fuel processor and fuel cell systems which improves stability of operation, simplifies control, and improves the heat recovery. According to the invention, a reforming zone is heated by indirect heat exchange with a first combustion effluent stream and provides a cooled first combustion effluent stream. The cooled combustion effluent stream is reheated in at least an additional combustion zone with at least a portion of the anode waste gas from the fuel cell to provide a reheated combustion effluent stream. The reheated combustion effluent stream is employed to further heat the reforming zone.

Abstract: A process is provided for the concentration and recovery of ethylene and heavier components from an oxygenate conversion process. A separation process such as a pressure swing adsorption (PSA) process is used to remove hydrogen and methane from a demethanizer overhead stream comprising hydrogen, methane and C2 hydrocarbons and subsequently return the recovered C2 hydrocarbons to be admixed with the effluent from the oxygenate conversion process. This integration of a separation zone with a fractionation scheme in an ethylene recovery scheme using an initial deethanizer zone resulted in significant capital and operating cost savings by the elimination of cryogenic ethylene-based refrigeration from the overall recovery scheme.

Abstract: A process is provided for the concentration and recovery of ethylene and heavier components from an oxygenate conversion process. A separation process such as a pressure swing adsorption (PSA) process is used to remove hydrogen and methane from a demethanizer overhead stream comprising hydrogen, methane, and C2 hydrocarbons and subsequently return the recovered C2 hydrocarbons to be admixed with the effluent from the oxygenate conversion process. This integration of a separation zone with a fractionation scheme in an ethylene recovery scheme using an initial demethanizer zone resulted in significant capital and operating cost savings by the elimination of cryogenic ethylene-based refrigeration from the overall recovery scheme.

Abstract: Hydrogen generation and fuel cell operation are integrated through the use of a low-cost hydrogen generation zone which comprises a pre-reforming zone, a partial oxidation zone, a reforming zone, and a water gas shift zone. Anode waste gas from the fuel cell is burned to provide heat to pre-reform the feed to the hydrogen generation zone while the burner exit temperature and the reforming zone exit temperatures are controlled to eliminate thermal cycling in the hydrogenation zone. This simplified control of the hot side temperatures in the hydrogen generation zone below about 700° C. combined with use of the pre-reforming zone, surprisingly permits the use of carbon steel and/or stainless steel for construction of the hydrogenation zone while providing an efficient system which does not require external fuel and offers a high degree of feedstock flexibility at low cost.

Abstract: Hydrogen generation and fuel cell operation are integrated through the use of a low-cost hydrogen generation zone which comprises a pre-reforming zone, a partial oxidation zone, a reforming zone, and a water gas shift zone. Anode waste gas from the fuel cell is burned to provide heat to pre-reform the feed to the hydrogen generation zone while the burner exit temperature and the reforming zone exit temperatures are controlled using a simplified control system to eliminate thermal cycling in the hydrogenation zone. This simplified control of the hot side temperatures in the hydrogen generation zone below about 700° C. combined with use of the pre-reforming zone, surprisingly permits the use of carbon steel and/or stainless steel for construction of the hydrogenation zone while providing an efficient system which does not require external fuel and offers a high degree of feedstock flexibility at low cost.

Abstract: An apparatus is provided which comprises two burner zones using a single igniter separated by a heat transfer zone for use in low-cost hydrogen generation units. When used in conjunction with a control system which limits the effluent temperature to less than about 700° C., the apparatus can be constructed of materials such as carbon steel and stainless steel rather than more exotic materials. This simplified structure and the use of less exotic materials provides an efficient, low-cost combined partial oxidation reactor for small-scale hydrogen production systems, especially for hydrogen production systems associated with fuel cell operation for the production of electricity.

Abstract: The invention provides a molten carbonate fuel cell system having a plurality of fuel cell stacks, with each fuel cell stack having an anode and a cathode. Each of the anodes includes an anode feed inlet and an anode exhaust outlet, and each cathode includes a cathode feed inlet and a cathode exhaust outlet. A combuster for receiving unreacted fuel from the anode exhaust outlet of a first one of the fuel cell stacks is connected to the cathode feed inlet of a second one of the fuel cell stacks for delivering exhaust from the combuster. An intercooler is disposed between the cathode exhaust outlet of the second fuel cell stack and the cathode feed inlet of the first fuel cell stack for cooling gases passing therebetween.