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Allothermal process

The gasifiers considered in this overview can be differentiated into direct (autothermal) and indirect (allothermal) processes. In the indirect processes, the heat needed to drive the endothermic heterogeneous reactions is provided by inert (circulating) solid material or by heat exchangers. The processes are... [Pg.192]

Before a C02-free hydrogen production will be established on the future energy market, it is desirable for a transition phase to replace autothermal with allothermal processes, where an adequate heat carrier system is taken to transfer heat from outside into the hydrocarbon splitting process. The output of hydrogen per unit feed stock may be increased by 30-40%. This strategy includes the production not only of hydrogen, but also of liquid energy alcohols in a subsequent step, e.g. methanol synthesis. [Pg.308]

These reactions are carried out in primary reformers containing a number of vertical catalyst-filled tubes. The heat of reaction is supplied externally e.g. by an allothermal process. [Pg.33]

Steam reforming (allothermal process) is the most widely used process for the production of syngas from methane. The important steam reforming reactions are shown in Reactions 2.1—2.3. Reaction 2.1 represents the endothermic steam reforming reaction where synthesis gas is produced in a 3 1 H2/CO ratio. [Pg.25]

The different gasification processes can be characterized 1) by the type of coal used and 2) by the coal s physical and chemical properties. On the other hand, the processes differ in the technology involved. For example the heat supply can be allothermal (i.e., external heating) or autothermal (i.e selfheating) and the reactor can be fixed-bed, fluidized-bed or entrained-bed. Furthermore, the actual gasification reaction and the gas composition are determined by46 ... [Pg.107]

The utilization of nuclear process heat in (allothermal) coal gasification plants e.g. with 950°C helium from high temperature nuclear reactors has been postponed to the distant future, due to the stopping of development work in the Federal Republic of Germany. [Pg.35]

The important factors in coal conversion are the physical and chemical properties of the coal, heat supply (autothermal or allothermal), reactor type (fixed bed, moving bed, fluidized bed, or entrained bed), gasification agent (air, oxygen, steam, or a combination thereof), and process conditions. Typically, coal conversion is carried out at high temperatures (900—1000 C) be-... [Pg.64]

With in situ H2O removal, the exothermic reactions in DME synthesis unit make possible the endothermic aqueous-phase glycerol reforming process, and the aqueous-phase glycerol reforming process produces the synthesis gas appropriate for DME synthesis process (Figure 5.15). Simulations surest that allothermal operation could be achieved the overall energy balance is favorable, and the synthesis gas produced in... [Pg.125]

To achieve temperatures in a reactor above 700 °C to maintain the reaction of gasification agent and feedstock, heat can be either added externally or generated internally. Based on heat supply to the process, allothermal, autothermal, and hydrogenating processes are distinguished. The main characteristics of the different types of heat supply are shown in Table 4.1. [Pg.108]

Referring to industrial applications of solid material, coal or petroleum coke represent the gasification feedstock, and mixtures of oxygen and steam are common gasifying agents. Most processes are pressurized and driven in autothermal mode. Allothermal and hydrogenating processes play only a minor role in terms of commercial coal processing. [Pg.108]


See other pages where Allothermal process is mentioned: [Pg.198]    [Pg.307]    [Pg.308]    [Pg.311]    [Pg.315]    [Pg.221]    [Pg.229]    [Pg.234]    [Pg.499]    [Pg.500]    [Pg.508]    [Pg.51]    [Pg.6]    [Pg.7]    [Pg.7]    [Pg.181]    [Pg.247]    [Pg.97]    [Pg.98]    [Pg.110]    [Pg.119]    [Pg.241]    [Pg.247]    [Pg.220]    [Pg.222]   
See also in sourсe #XX -- [ Pg.25 ]




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