Hydrogen production reactors

Based on a similar concept, SGR process shown in Figure 17.8 is developed where syngas, rather than coal, is fed into the fuel reactor to reduce the Fe203 particles and then produce H2 in the hydrogen production reactor. 

Figure 23.6 One reactor element (out of 30) for a proposed hydrogen production reactor skid (10 s ) built byVelocys[13].

Figure23.7 Schematic of a full-scale hydrogen production reactor skid (lOm s ) designed by Velocys [13].

In a hydrogen production reactor, metal iron produced in the fuel reactor reacts with steam to produce hydrogen and iron oxide that is recycled back to the fuel reactor to close the loop. Similar to the SCL process, some magnetite is formed and can be regenerated by oxidation in a combustion reactor to produce Fe20g particles. 

Weapons materials from production reactors were accumulated during the Cold War period as a part of the U.S. defense program. Prominent were tritium, ie, hydrogen-3, having a of 12.3 yr, and plutonium-239, 1/2 = 2.4 X lO" yr. The latter constitutes a waste both as a by-product of weapons fabrication in a waste material called transuranic waste (TRU), and as an excess fissionable material if not used for power production in a reactor. 

Shift Conversion. Carbon oxides deactivate the ammonia synthesis catalyst and must be removed prior to the synthesis loop. The exothermic water-gas shift reaction (eq. 23) provides a convenient mechanism to maximize hydrogen production while converting CO to the more easily removable CO2. A two-stage adiabatic reactor sequence is normally employed to maximize this conversion. The bulk of the CO is shifted to CO2 in a high... 

A similar but somewhat less ambitious approach is to carry out dehydrogenation of ethylbenzene and oxidation of the hydrogen product alternately in separate reactors containing different catalysts ... 

The formation of hydrogen is accompanied with VFAs or solvent production during an anaerobic digestion process. Therefore, the distribution of VFA concentrations and their finctions is a usefiil indicator for monitoring hydrogen production. Fig. 3 shows the variations in alcohol and VFAs. Most of the VFAs were analyzed as acetate and butyrate, and most of the alcohols were analyzed as ethanol. The propionate concentration was below the analytical limit. It indicates that the anaerobic pathway in the reactor is not propionic-type fermentation but but5nrate-type fermentation. Clostridium butyricum is considered to be the dominant... 

Hydrogen production from biomass>ethanol at ambient temperature with novel diaphragm reactor... 

Simplified schematics of hydrogen production by SMR. (a) SMR with solvent removal of C02 and a methanation unit, (b) SMR with a PSA unit. HT- and LT-WGS high- and low-temperature WGS reactors, respectively. 

Schematics of cyclic (a) and continuous (b) reactor for hydrogen production by steam-iron process. I—IV denote the reactor zones.

Barbiery, G. et al., Hydrogen production using membrane reactor, Korean Membrane., 5,68,2003. 

Hydrogen Production with Very High-Temperature Reactor.147... 

Hydrogen Production with Very High-Temperature Reactor 4.4.1 Overview of the Very High-Temperature Reactor... 

---