Abstract:
Tube-bundle heat exchange unit (1) for internals of heat exchangers or reactors, comprising: at least one tube bundle (2); a plurality of baffles (3) associated with said tube bundle and defining through-openings according to a predefined arrangement, each opening being passed through by one of more tubes of the tube bundle, and a shell (6) which surrounds said tube bundle and said baffles, wherein the assembly of the tube bundle and the shell can be disassembled and the shell is structurally collaborating with the tube bundle through said baffles.
Abstract:
In order to provide a chemical reaction apparatus that can suppress a situation where microwaves are concentrated on a partial portion in a reactor, and that can more uniformly irradiate a content with the microwaves, a chemical reaction apparatus includes: a horizontal flow-type reactor in which a liquid content horizontally flows with an unfilled space being provided thereabove; a microwave generator that generates microwaves; and a waveguide that transmits the microwaves generated by the microwave generator to the unfilled space in the reactor, wherein a top of the reactor is curved with respect to a flow direction of the content.
Abstract:
A tar destruction unit for a biomass gasifier is described, comprising a catalyst and/or heating means situated within the free-board section of the gasifier. Also described is a biomass gasifier having such a tar destruction unit.
Abstract:
A method for formaldehyde production through catalytic oxidation of methanol, comprising the steps of feeding to a first oxidation catalytic bed (2) a gas flow comprising methanol and oxygen at a predetermined crossing linear flow rate, obtaining at the outlet of said first catalytic bed (2) a flow of gaseous reaction products comprising unreacted methanol, and feeding the flow of gaseous products to a second oxidation catalytic bed (6) is distinguished by the fact that the flow of gaseous reaction products comprising unreacted methanol is fed to the second catalytic bed (6) with a crossing linear flow rate substantially equal to said predetermined first catalytic bed (2) feeding flow rate.
Abstract:
An improved feedstock for fuel processing systems, and fuel processing systems incorporating the same. The fuel processing system includes a fuel processor adapted to produce a product hydrogen stream from a carbon-containing feedstock. The fuel processing system may also include a fuel cell stack adapted to produce an electric current from the product hydrogen stream. The feedstock is at least substantially formed of a hydrocarbon or alcohol. In an exemplary embodiment, the feedstock includes methanol. The feedstock also includes at least one odorant adapted to produce a strong and characteristic odor, even when present in only low concentrations. The odorant, or odorants, are selected to be free or at least sufficiently free from compounds that will poison the catalyst used in the fuel processor.
Abstract:
The present invention is directed to a fuel reformer device that produces a hydrogen rich gas from a hydrocarbon and steam. The steam reforming reaction that produces the hydrogen rich gas from the hydrocarbon and steam is endothermic. A known technique supplies heat required for the steam reforming reaction by an exothermic oxidation reaction proceeding in parallel with the steam reforming reaction. This known technique may, however, cause an excessive temperature rise in an area of the vigorous oxidation reaction in the fuel reformer device.A reformer unit 34 including a Cu—Zn catalyst receives a supply of a crude fuel gas containing the air flown through a second fuel supply conduit 64. The crude fuel gas is subjected to the steam reforming reaction and the oxidation reaction proceeding inside the reformer unit 34. A resulting hydrogen rich gaseous fuel is discharged to a third fuel supply conduit 65. The reformer unit 34 includes an upper stream reaction unit 80 and a lower stream reaction unit 81. Both the reaction units 80 and 81 have honeycomb structures, wherein the total sectional area of the flow path in the upper stream reaction unit 80 is made smaller than the total sectional area of the flow path in the lower stream reaction unit 81. This arrangement causes the gas flowing through the reformer unit 34 to have the higher flow velocity on the upstream side than on the downstream side. The higher flow velocity on the upstream side extends the area of the vigorous oxidation reaction to the lower stream portion and enables the heat generated on the upstream side to be effectively transmitted to the lower stream portion. This arrangement thus effectively prevents an excessive temperature rise on the upstream side.
Abstract:
An improved feedstock for fuel processing systems, and fuel processing systems incorporating the same. The fuel processing system includes a fuel processor adapted to produce a product hydrogen stream from a carbon-containing feedstock. The fuel processing system may also include a fuel cell stack adapted to produce an electric current from the product hydrogen stream. The feedstock is at least substantially formed of a hydrocarbon or alcohol. In an exemplary embodiment, the feedstock includes methanol. The feedstock also includes at least one odorant adapted to produce a strong and characteristic odor, even when present in only low concentrations. The odorant, or odorants, are selected to be free or at least sufficiently free from compounds that will poison the catalyst used in the fuel processor.
Abstract:
A process and apparatus for contacting reactants with a particulate catalyst while indirectly heating the reactants with a heat exchange medium improves temperature control by using an intermediate heat exchange fluid and system to prevent overheating of reactants and maintain parallel heating characteristics through multiple reaction-heat exchange zones. The internal flow path minimizes the circulation of the reaction zone heat exchange fluid by incorporating interstage reheating of the reaction zone heat exchange fluid as it passes in series flow. A particularly useful application of the process and apparatus is in the dehydrogenation of ethyl benzene to produce styrene. The process and apparatus can also be used with simultaneous exchange of catalyst particles by an operation that restricts reactant flow while moving catalyst through reaction stacks in which the reactant flow has been restricted.
Abstract:
The invention concerns a process and an apparatus for performing chemical reactions under pressure in the presence of a solid catalyst in a multi-stage reaction zone, after external intermediary thermal conditioning. This process may be used for the synthesis of ammonia or methanol or for gasoline reforming. It is characterized in that at least one reaction fluid is introduced into at least one compartment, a first reaction effluent is recovered, a heat exchange takes place, outside the reaction zone, between a first effluent and an external heat exchange medium, then the first effluent is introduced into at least one subsequent compartment and a second reaction effluent is recovered from the subsequent compartment. The reaction fluid or reaction effluent circulates cross-wise in the compartments substantially perpendicularly to the reaction zone, the compartments being tight and of elongate shape, each compartment being adjacent to one or two other compartments, each group of two adjacent compartments comprising a common partition wall, either substantially parallel to generatrix or substantially oblique with respect thereto.
Abstract:
The system to reduce the energy consumption of heterogeneous synthesis reactors, particularly of ammonia reactors, f.i. the "Chemico"-type reactor, foresees the insertion of two cylindrical walls at least partially perforated in order to annularly delimit the catalytic beds; the first outer wall (Fe) having a diameter (Di) slightly smaller than diameter (Dc) of the cartridge (C), has a height (Hi) higher than (H'i) of the internal cylindrical wall (Fi) which has a diameter inferior to the above mentioned (Di), but superior to the external diameter (Dt) of the central feed pipe (T) of the quench gas (QG). The top (SO) of the internal cylindrical wall (Fi) is closed by a cover (CO) that has a distance from the bottom (FO) of the basket equal to the mentioned height (H'i) of the internal cylindrical wall. The catalytic bed is therefore annular in diameter (Di-D'i) on all of the said height (H'i), but is substantially cylindrical (of diameter Di) on the height (Hi-H'i).In the substantially annular zone (Q) between the cylindrical internal perforated wall (Fi) and the external face of the pipe (T), which is also at least partially perforated, the reacted and quench gases are collected.