Combustion reactor system

Bischi, A., Langprgen, 0., Morin, J.-X. et al. (2011) Performance analysis of the cold flow model of a second generation chemical looping combustion reactor system. Energy Procedia, 4,449 56. 

Runs at 10°C for both CFC-11 and CFC-113 were conducted in the circulating reactor system to examine temperature effects. In both cases, the apparent first-order rate constant declined slightly. The decline was somewhat lower for CFC-113 than for CFC-11, which may even have remained unchanged. A sonochemical approach has the advantage of not requiring any transference of the target molecule from an aqueous phase as would be required in combustion or catalytic oxidation. 

Another apparently undesirable aspect is the general layout of the reactor systems used in combination with the analysis technique [3-5]. The arrangement of samples on flat plates can be an acceptable compromise when it comes to simple reactions with essentially one reaction product, as with CO oxidation to C02 or the combustion of H2 and 02 to water. In the latter case, diffusion limitations... 

In the particular reactor system employed, structure of the black is more easily controlled by injecting the selected feedstock as a liquid, rather than as a vapor or gas. In this case, the distribution of the oil injected into the combustion chamber can be controlled by mechanical means. The point of initiation of the reaction can also be moved along a line in the reactor to make it short or long at will. Structure then is more dependent upon the feedstock, its boiling range and preheat temperature, and the point within the reactor selected for reaction initiation. Structure can also, of course, be altered downward through the use of feedstock additives. 

A 2002 study reports the use of a microreactor system to increase rate of production of EO (72). The use of microreactors eliminates the formation of hot spots that are common in large reactor systems. Hot spots commonly affect selectivities by increasing the amount of combustion products formed. Microreactor systems also make harmful waste products easier to handle and limit the size of explosions if they occur. 

The procedure for writing and solving material balances for a combustion reactor is the same as that for any other reactive system. Bear in mind these points, however ... 

One of the more innovative pyrolytic gasification processes is an indirectly heated, fluid-hed system (c/. Alpert et al, 1972 Bailie, 1981 Paisley, Feldmann, and Appelbaum, 1984). This system uses two fluid-bed reactors containing sand as a heat transfer medium. Combustion of char formed in the pyrolysis reactor takes place with air within the combustion reactor. The heat released supplies the energy for pyrolysis of the combustible fraction in the pyrolysis reactor. Heat transfer is accomplished by flow of hot sand from the combustion reactor at 950°C to the pyrolysis reactor at 800°C and return of the sand to the combustion reactor (Fig. 9.5). This configuration separates the combustion... 

In general, the gas-phase chemical reduction system effectively destroyed PCBs, reducing them to lighter hydrocarbons. Theoretically, the destruction process could depend on both the reactor system s gas-phase reduction reactions, which produced the reformed gas, and on the propane/reformed gas-fired boiler, a combustion device. 

We shall develop next a single-channel model that captures the key features of a catalytic combustor. The catalytic materials are deposited on the walls of a monolithic structure comprising a bundle of identical parallel tubes. The combustor includes a fuel distributor providing a uniform fuel/air composition and temperature over the cross section of the combustor. Natural gas, typically >98% methane, is the fuel of choice for gas turbines. Therefore, we will neglect reactions of minor components and treat the system as a methane combustion reactor. The fuel/air mixture is lean, typically 1/25 molar, which corresponds to an adiabatic temperature rise of about 950°C and to a maximum outlet temperature of 1300°C for typical compressor discharge temperatures ( 350°C). Oxygen is present in large stoichiometric excess and thus only methane mass balances are needed to solve this problem. 

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