Abstract: Color from dyes is removed from secondary pulps with non-chlorine based bleaching agents in treating sequences using oxygen with combinations of peroxide, ozone, and/or hydrosulfite at controlled pH conditions (less than 8 or greater than 10). Acid treatment prior to bleaching steps improves color removal and protects fibers from damage at more severe bleaching conditions.

Abstract: Methanol is produced from synthesis gas comprising hydrogen, carbon monoxide, and carbon dioxide in a two-stage liquid phase reactor system. Each reactor is operated in an optimum temperature range to maximize methanol productivity, and once-through product conversion of up to 9.1 moles methanol per 100 moles of synthesis gas can be achieved with reasonable catalyst utilization. Overall catalyst utilization is increased by countercurrent catalyst transfer. In an alternate mode of operation, the liquid phase reactor system is integrated with a coal gasification combined cycle (CGCC) power generation process wherein the unreacted synthesis gas is used as fuel in a gas turbine-driven electric power generator. Operation of each liquid phase reactor in the optimum temperature range maximizes the available heat of reaction which is recovered as steam; the steam is utilized in the gas turbine combustor or the CGCC steam turbine.

Abstract: A method for controlling the operation of a liquefied natural gas (LNG) process which utilizes gas turbine-driven refrigeration compressors is disclosed. A feedforward control system compensates for the effects of changes in ambient air temperature on the plant operating efficiency by periodically predicting a new temperature and resetting the set points of key feedback controllers in anticipation of this new temperature, thereby optimizing the operation of the plant and minimizing the specific fuel consumption at a given LNG production rate.

Abstract: Composite semipermeable membranes comprising porous adsorptive material supported by a porous substrate are disclosed for use in a process for the separation of multicomponent gas mixtures. In the process, one or more primary components adsorb within the pores of the adsorptive material and diffuse by surface flow through the membrane to yield a permeate stream enriched in one or more of the primary components. Methods for making the composite membranes are described.

Abstract: A method is disclosed for producing ammonia synthesis gas by splitting a methane stream, combusting a portion of the methane with steam and oxygen-enriched air, converting a second portion of the methane with steam in a reformation heated by the combustion products of the first portion and combining the two portions for the water gas shift reaction followed by adsorptive separation of contained carbon dioxide.

Abstract: An improved electric arc spray process for the deposition of reactive metals is disclosed which utilizes compressed inert gases for atomization. The improved process utilizes argon, nitrogen, carbon dioxide, sulfur hexafluoride, or mixtures thereof supplied to the arc spray gun such that the mass ratio of the wire feed rate to the gas feed rate is greater than 0.10. The process can be used to coat various substrates with metals or alloys comprising magnesium, zinc, lithium, and other reactive metals. The process is useful for the application of cathodic corrosion protective coatings on various substrates.

Abstract: Nitrogen is economically recovered from the flue gas evolved in a hydrocarbon steam reforming furnace by hydrogenation of free oxygen therein and removal of carbon dioxide and other minor impurities from the flue gas by pressure swing adsorption with recovery of high purity nitrogen as unsorbed effluent. The process is utilized to highest advantage in the production of ammonia syngas wherein natural gas or other hydrocarbon feed is subjected to steam reforming in a fuel-fired furnace. The nitrogen obtained by purification of the flue gas is combined with the purified hydrogen separated from the reformate providing the syngas for conversion to ammonia. In a preferred embodiment, the steam reforming is carried out in two stages, the first stage being performed in a conventional fuel-fired steam reforming furnace to which a major portion of the fresh hydrocarbon feed is charged.

Abstract: A process for making high purity argon is disclosed in which crude argon containing less than about 0.8 mol % oxygen is recovered from air in a cryogenic distillation system, the crude argon is purified by removing oxygen in a getter system, and other impurities are removed by cryogenic distillation to yield a high purity argon product. The crude argon purification system is heat integrated with the main cryogenic air separation system. High purity argon can be produced at argon recoveries greater than 90% by utilizing structured packing in at least a portion of the argon sidearm column.

Abstract: The present invention relates to a water-gas shift process which is carried out in a non-aqueous, high boiling liquid medium, either in an ebullated or slurry mode. The function of the liquid is to provide a heat sink for the exothermic reaction thereby allowing for better performance and longer catalyst life. The process, termed "liquid phase shift" (LPS) preferably uses commercially available vapor-phase low temperature shift (LTS) catalysts to accomplish the shift reaction. Because of the isothermality of the LPS process and its ability therefore to take advantage of higher catalyst activity, the average operating temperature is typically 260.degree. C. (500.degree. F.). This compares favorably to the lower average operating temperature for the conventional vapor-phase LTS process, which is typically 240.degree. C. (465.degree. F.). In addition, the LPS process can handle high carbon monoxide content feeds, e.g. 75 vol % carbon monoxide on a dry basis, without experiencing excessive catalyst deactivation.

Abstract: A process for the liquefaction of natural gas is disclosed wherein expansion valves for low-level multicomponent refrigerant and liquefied gas product streams are replaced with process-loaded turboexpanders having liquid inlet streams. Each turboexpander is coupled with a compressor or pump so that expansion work extracted from a given stream is used directly to compress or pump the stream prior to cooling and expansion. The use of process-loaded turboexpanders reduces the minimum work of liquefaction and increases the liquefaction capacity of the process.

Abstract: A method is disclosed for the thermal regeneration of an adsorbent which contains adsorbed components which can react with and damage the adsorbent at regeneration temperatures. The method comprises passing a hot regeneration gas through a bed of the adsorbent at a sufficiently high flow rate such that the residence time and reaction of the desorbed components in the adsorbent bed are minimized. For removing water from CaX or SrX zeolites, the flow of nitrogen regeneration gas is controlled so that the nitrogen gas residence time in the bed is less than one second.

Abstract: The present invention relates to an improvement to a process for the production of methanol from synthesis gas containing carbon monoxide and hydrogen utilizing a three phase or liquid-phase reaction technology. The improvement to the process is the addition of relatively small amounts of water to the liquid-phase reactor thereby allowing for the use of a CO-rich synthesis gas for the production of methanol by effectuating in the same reactor the methanol synthesis and water-gas shift reactions. A portion of the unreacted synthesis gas stream from the liquid-phase reactor is separated into a hydrogen-rich component and a carbon monoxide-rich component.

Abstract: An improved pressure swing adsorption process is disclosed for the recovery of high-purity primary and secondary components from a multicomponent gas mixture. The process utilizes a first group of absorbent beds selective for the secondary component and a second group of adsorbent beds selective for retention of tertiary impurities in the mixture. The gas mixture is passed through a first and second bed in series, very high purity primary component product is discharged from the second bed, and high purity secondary component product is recovered by desorption from the first bed. A low-pressure purge of the first bed with high-purity secondary component product is utilized to minimize compression power and improve purity of the secondary product component. Several novel pressure equalization steps improve primary product recovery and reduce power consumption. Further increased product recovery is realized by recycling depressurization and purge streams from the first bed.

Abstract: An improved pressure swing adsorption process is disclosed for the recovery of two individual components from a multicomponent gas mixture. The process utilizes a first group of adsorbent beds selective for the secondary component product and a second group of beds selective for tertiary impurities in the mixture. The gas mixture is passed through the first and second beds in series and high purity primary component product is discharged from the second beds. The secondary component product is recovered by desorption from the first beds. Product recovery is improved by recycling depressurization gas from the first beds and by several novel pressure equalization steps. The process can be used to recover high-purity hydrogen and carbon dioxide from a gas mixture containing these components along with minor amounts of methane, carbon monoxide, and nitrogen.

Abstract: A process and apparatus are disclosed for recovering olefins, particularly C.sub.3, C.sub.4, and C.sub.5 olefins, from gaseous mixture thereof with lower-boiling components. The olefin-containing gas mixtures is compressed and cooled to yield vapor and condensate streams, the vapor stream is further cooled forming additional condensate, both condensate streams are combined and adiabatically flash evaporated, and the remaining liquid is distilled to recover the desired olefins in a liquid bottoms products. Flash vapor, and optionally the distillation vapor product, are recycled to the compression step.