Abstract: A process is set forth for converting synthesis gas into dimethyl ether (DME) in a single step comprising contacting the synthesis gas with a bifunctional catalyst system having a methanol synthesis functionality and a methanol dehydration functionality. In particular, the present invention is an improvement to said process for increasing the stability of the bifunctional catalyst system, particularly when the process is conducted in the liquid phase. The improvement comprises introducing a methanol containing stream into the DME reactor such that the methanol concentration throughout the DME reactor is maintained at a concentration greater than 1.0%, generally between 4.0% and 8.0%. In one embodiment of the present invention, the methanol containing stream comprises at least a portion of the byproduct methanol from the DME reactor such that said portion of byproduct methanol is introduced into the DME reactor as a recycle stream.

Abstract: A technique is set forth to reduce the heat requirement of conventional distillation processes which separate feed mixtures containing three or more components. The technique provides a great deal of flexibility in adjusting the temperatures of the required utilities including a scenario where the heat requirement is reduced without a need for additional higher temperature (and more costly) heat utility. In this technique, when a liquid bottoms stream (or gaseous overhead stream) containing two or more components is sent from an earlier column to a subsequent column, then a return vapor (or liquid) stream is implemented between the same locations in the two columns.

Abstract: In a method of forming a frozen food product, the temperature of a fluid food product is lowered so that the product is plastic. A mould is pressed against the food product to cause at least a portion of the product to take up the shape of the mould. The mould is at a sufficiently low temperature when it is pressed against the product such that the product retains its moulded shape and such that the product is readily releasable from the mould. This allows frozen confectionery products such as ice cream to be successfully moulded.

Abstract: A process is set forth for the cryogenic distillation of an air feed to produce at least two oxygen-rich gaseous streams having different oxygen purities. The process uses a mixing column system in addition to a distillation column system. A key to the process is that at least two oxygen-rich liquid streams having different oxygen purities are transferred from the distillation column system to the mixing column system in order to produce the oxygen-rich gaseous streams.

Abstract: A diesel fuel composition is set forth for an increased cetane number vis-a-vis conventional diesel fuel compositions. The composition generally comprises one or more compounds selected from the dialkoxy alkane (DAAK) chemical family. In a preferred embodiment of the present invention, the diesel fuel composition consists of moderate amounts of dimethoxy propane (DMPP) and dimethoxy ethane (DMET) blended into a conventional diesel fuel.

Abstract: A process is set forth for the selective removal of water, CO.sub.2, ethane and C.sub.3 + hydrocarbons from gas streams, particularly a natural gas stream comprising primarily methane. The process comprises contacting the gas stream with an adsorbent material consisting exclusively of one or more compounds which are basic (i.e. compounds which, when contacted with a pH neutral aqueous solution, cause such solution to have a pH greater than 7.0) and which are mesoporous (i.e. compounds which have moderately small pores providing a surface area less than 500 m.sup.2 /g). The key to the present invention is the use of a single homogenous adsorbent without sacrificing performance. Typical mesoporous adsorbents which are useful in the present invention include zinc oxide, magnesium oxide and, in particular, activated alumina.

Abstract: A process is set forth for the cryogenic distillation of an air feed to produce oxygen and argon and is particularly applicable where high purity oxygen and ultra-high purity argon are required and where only moderate argon recovery is required. A key to the present invention is that the argon column is divided into a lower section and an upper section and the impure argon overhead from the lower section is split into three portions. The first portion is further distilled to the desired purity in the top section, the second portion is condensed and returned as reflux to the lower section, and the third portion is removed as an impure argon stream. Such a scheme allows one to reduce the diameter of the argon column's top section, thereby providing a capital cost savings.

Abstract: The present invention pertains to a process for the coproduction of methanol and dimethyl ether (DME) directly from a synthesis gas in a single step (hereafter, the "single step DME process"). In this process, the synthesis gas comprising hydrogen and carbon oxides is contacted with a dual catalyst system comprising a physical mixture of a methanol synthesis catalyst and a methanol dehydration catalyst. The present invention is an improvement to this process for providing an active and stable catalyst system. The improvement comprises the use of an aluminum phosphate based catalyst as the methanol dehydration catalyst. Due to its moderate acidity, such a catalyst avoids the coke formation and catalyst interaction problems associated with the conventional dual catalyst systems taught for the single step DME process.

Abstract: An open loop, air refrigerant heat pump process is set forth for producing a refrigerated atmosphere inside an enclosed space, in particular the enclosed space of a food freezer. A key to the present invention is that it uses a portion of the cold expander discharge to cool the air feed to the expander, prior to using said portion as a regeneration gas for the front end, adsorbent-containing drier. This is key because it allows one to eliminate the prior art's need to recover refrigeration from the air exiting the enclosed space which, more importantly, allows one to eliminate the prior art need to remove any cryogenically generated ice that the air picks up inside the food freezer.

Abstract: A process is set forth for the cryogenic distillation of an air feed to produce an oxygen product, particularly an oxygen product at moderate purity (80-99%, preferably 85-95%). The process uses an auxiliary low pressure column in addition to the conventional high pressure column and low pressure column. The auxiliary low pressure column, which is preferably operated at the same pressure as the main low pressure column and which is heat integrated with the top of the high pressure column by means of its bottom reboiler/condenser, pretreats the crude liquid oxygen from the bottom of the high pressure column. The resulting overhead vapor stream and bottom stream are subsequently fed to the main low pressure column. Preferably, the bottom stream is fed to the main low pressure column in a state which is at least partially vapor.

Abstract: A process is set forth for the cryogenic distillation of an air feed to produce nitrogen, particularly high pressure nitrogen of various purity, varying from low purity (up to 98% nitrogen) to ultra-high purity (less than 1 part per billion of oxygen). The nitrogen may be produced at two different pressures and two different purities. The process uses an auxiliary low pressure separation zone in addition to the conventional high pressure column and low pressure column. The auxiliary low pressure separation zone, which is operated at the same pressure as the low pressure column and which is heat integrated with the top of the high pressure column by means of its bottom reboiler/condenser, pretreats the crude liquid oxygen from the bottom of the high pressure column.

Abstract: A process is set forth for the cryogenic distillation of an air feed to produce high pressure nitrogen of various purity, varying from moderately high purity (99.9% nitrogen) to ultra-high purity (less than 1 part per billion of oxygen). The process is particularly suited for cases where the high pressure nitrogen is needed directly from the distillation column system to avoid contamination concerns associated with compressing nitrogen that is produced at lower pressures. The process uses a high pressure column, which operates at a pressure to directly produce the nitrogen at the desired high pressure, and one or more lower pressure columns which produces a portion of the nitrogen product at a lower pressure. At least a portion of the lower pressure nitrogen is compressed and fed to the high pressure column at a location which is below the removal location of the high pressure nitrogen.

Abstract: A process is set forth for introducing a multicomponent liquid feed stream at pressure P.sub.2 into a distillation column operating at lower pressure P.sub.1. The process comprises removing a split stream from the feed stream, reducing its pressure and using the resulting stream to subcool the feed stream. After being subcooled, the feed stream is also reduced in pressure and both streams are fed to different stages of the distillation column. An important embodiment of the present invention is within the standard double column air separation cycle where the multicomponent liquid stream is the crude liquid oxygen stream from the bottom of the high pressure column which must be reduced in pressure prior to its introduction into the low pressure column.

Abstract: A tunnel freezer is cooled by selectively supplying liquid nitrogen to banks of spray nozzles. The banks are switched on and off as required so that at any given time the pressure upstream of each operational spray nozzle will be substantially constant at a level which closely approximates the maximum heat transfer coefficient associated with the spray nozzle or the maximum effectiveness of the spray nozzle or a balance therebetween. The invention is in contrast to the prior art where the flow of liquid nitrogen to the spray nozzles is continuously varied in response to the thermal load.

Abstract: The present invention is an immersion freezer which employs a postcooling chamber. The immersion section of the freezer initially immerses all or part of the items to be frozen (typically food items) in a bath of a liquid refrigerant to impart a crust freeze on the items, which locks in moisture and prevents clumping. The postcooling chamber, located underneath the immersion section, then uses the vaporized refrigerant from the immersion section to complete the freezing process while also maximizing efficiency. The postcooling chamber also imparts agitation to the items (which further prevents clumping) through the use of a series of cascading conveyor belts.

Abstract: A staged oxy-fuel burner for producing a generally flat fuel rich flame overlying a highly radiative fuel lean flame, the burner having a fuel passage terminating in a nozzle, the fuel passage and nozzle having a generally elongated cross-section, a housing of complementary shape surrounding the fuel passage, so that when fuel is introduced into the fuel passage and an oxidizer is introduced into the passage defined by a space between the housing and the fuel passage a generally flat fuel rich flame is produced at the nozzle end of the fuel conduit and a staging nozzle for introducing oxidizer underneath and in a shape complementary to said fuel rich flame to produce a highly radiative fuel lean flame under said fuel rich flame.

Abstract: Method and apparatus for reducing NOX production in an air-oxygen-fuel combustion process by creating post mix oxy-fuel flame and introducing air around said oxy-fuel flame at an angle of greater than 0.degree. to 90.degree. to the longitudinal axis of the oxy-fuel flame.

Abstract: An oxy-fuel burner for producing a generally flat luminous flame, the burner having fuel passage terminating in a nozzle, the fuel passage and nozzle having a generally elongated cross-section, a housing of complementary shape surrounding the fuel passage, so that when fuel is introduced into the fuel passage and an oxidizer is introduced into the passage defined by a space between the housing and the fuel passage a generally flat luminous flame is produced at the nozzle end of the fuel conduit. A precombustor having a cross-sectional shape complementary to that of flame end of the burner can be disposed on the flame end of the burner housing to further enhance combustion and protect the burner from the furnace atmosphere.

Abstract: The present invention is an ammonia injection scheme for NO.sub.x reductions that also reduces ammonia slip wherein the NO.sub.x containing gas to be treated is upstream of a cyclone separator. The reduction in ammonia slip is accomplished by injecting the ammonia through the outside wall of the cyclone inlet duct.

Abstract: A process is set forth for the synthesis of a C.sub.2 + aliphatic alcohol from hydrogen and carbon oxides in the presence of a copper-based catalyst which has been impregnated with an alkali metal compound. The process differs from the prior art in that the catalyst is impregnated with the alkali metal compound in the same slurry reactor which is used for reacting the hydrogen and carbon oxides. By contrast, in the prior art C.sub.2 + aliphatic alcohol synthesis, impregnation of the copper-based catalyst with the alkali metal compound is accomplished by a separate step in a separate vessel. By eliminating this separate step, the present invention realizes a savings in processing and equipment costs.