Methane reforming reactors

Adris, A M., Pruden, B.B., Lim, C. J. and Grace, J.R., 1996, On the Reported Attempts to Radically Improve the Performance of the Steam Methane Reforming Reactor, Canadian J. Chem. Eng., 74, pl77. 

The hydrothermal stability of the materials is more important as far as the use of membranes in methane reforming reactor is concerned. In general, improving the hydrothermal stability of membranes is difficult owing to the metastable nature of porous, particularly microporous structures and their tendency to change in the way of surface area reduction. Yet, recent reports [33, 34] show that improvements have been made in the hydrothermal stability of membranes based on silica, a material... 

Godini, H.R., Xiao, S., Kim, M., Gorke, O., Song, S., and Wozny, G. (2013) Dual-membrane reactor for methane oxidative coupling and dry methane reforming reactor integration and process intensification. Chem. Eng. Process. Process Intensif., 74, 153-164. 

Adris A.M., Pruden B.B., Lim C.J. and Grace J.R., (1996), On the reported attempts to radically improve the performance of the steam methane reforming reactor ,... 

However, many reactions of commercial interest have chemistry, mechanical, or system requirements that preclude the use of cross-flow reactors. Processes cannot use a cross-flow orientation primarily because of high temperatures and the need to internally recuperate heat such as steam methane reforming (SMR) [12, 13] and oxidation reactions [14]. Counter- and coflow devices require a micromanifold to dehver sufficiently uniform flow to each of the many parallel channels. 

Methane reforming reaction is accomplished under the action of heat collected from mirror concentrator of solar light. The mixture of CO and H2 produced in this reaction can be stored and then, when necessary, converted into high-potential heat (with the temperature up to 950 K) in the methanation catalytic reactor. The efficiency of solar-to-chemical energy conversion as high as... 

Pretreated NG feedstock is mixed with steam (2.6 MPa), the resulting mixture is preheated to 500°C and introduced to the catalytic reforming reactor. In the reforming reactor, the steam-methane mixture is passed through externally heated reformer tubes filled with Ni catalyst, where it is converted to CO and H2 at 850-900°C according to the following equation ... 

Steam methane reforming with membrane WGS reactor for hydrogen production. 

Because Pd-alloy membranes operate at high temperatures in the range of WGS reaction and on the lower end of methane reforming reaction, they can be used in a membrane reactor configuration for the simultaneous separation of hydrogen. As discussed earlier,... 

An integrated proof-of-concept (POC) size fluidized-bed methane reformer with embedded palladium membrane modules for simultaneous hydrogen separation is being developed for demonstration (Tamhankar et al., 2007). The membrane modules will use two 6 in. X 11 in. Pd-alloy membrane foils, 25-pm thick, supported on a porous support. The developmental fluidized-bed reactor will house a total of five (5) membrane modules with a total membrane area of about 0.43 m2 and is scheduled for demonstration by September 2007. 

The CH4 in the natural gas is usually converted to H2 and CO in a SR reactor. Steam reforming reactors yield the highest percentage of hydrogen of any reformer type. The basic SR reactions for methane and a generic hydrocarbon are ... 

The pyrolytic reforming reactor was a packed bed in a quartz tube reactor. Quartz was selected to reduce the effect of the reactor construction material on the hydrocarbon decomposition rate. ° The reactor was packed with 5.0 0.1 g of AC (Darco KB-B) or CB (BP2000) carbon-based catalyst. The reactor was heated electrically and operated at 850—950 °C, and the reactants had a residence time of 20—50 s, depending on the fuel. The reactor was tested with propane, natural gas, and gasoline as the fuels. Experiments showed that a flow of 80% hydrogen, with the remainder being methane, was produced for over 180 min of continuous operation.The carbon produced was fine particles that could be blown out... 

Carbonaceous compounds can also form in the absence of a catalyst by free-radical, gas-phase condensation reactions. The formation of this pyrolytic carbon is known in steam-reforming reactors where it can be controlled to some extent by minimizing the free volume within the reactor chamber. This type of carbon does not form readily with methane but can be severe with larger hydrocarbons. The compounds formed by free-radical reactions tend to be quite different from the graphitic carbon formed by metal catalysts. For example, Lee et al. showed that the compounds formed by passing pure, undi-... 

Methane reforming units receive methane-rich gas from a cryogenic product recovery facility and subject the gas to partial oxidation. Some of the carbon dioxide content is removed and the gas recycled to the reactors. Once liquids are recovered, the stream goes to essentially conventional refining units. The plant s production is primarily transport fuels. Most of the gasoline production is currently sold to other refineries for blending with their stocks, but a portion of the product is marketed directly to consumers. 

Steam methane reforming 93 Pressure-swing adsorptive reactor (PSAR)... 

Hydrocarbon Reforming 4 [HCR 4] Compact Membrane Reactor for Autothermal Methane Reforming... 

Methane and air were fed to the reactor with an O/C ratio of 1.0 and additional steam at different S/C ratios. The reaction was performed under atmospheric pressure and a nitrogen flow was maintained on the permeate side. The results obtained with the membrane were compared with others generated with the same reactor type without a catalytic membrane in the temperature range 400-575 °C, which is low for methane reforming [51]. 

The reactor can operate with either a liquid-phase reaction or a gas-phase reaction. In both types, temperature is very important. With a gas-phase reaction, the operating pressure is also a critical design variable because the kinetic reaction rates in most gas-phase reactions depend on partial pressures of reactants and products. For example, in ammonia synthesis (N2 + 3H2 O 2NH3), the gas-phase reactor is operated at high pressure because of LeChatelier s principle, namely that reactions with a net decrease in moles should be mn at high pressure. The same principle leads to the conclusion that the steam-methane reforming reaction to form synthesis gas (CH4 + H20 O CO + 3 H2) should be conducted at low pressure. 

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