Effects of wet CO oxidation on the operation of engines and power generators

Abstract

A simplified method is used to determine the optimum water content in the flue gases of charcoal gasifiers to be utilized as alternative fuels in the operation of engines and gas turbines for power generation. Computational models of plug flow reactors and well stirred reactors are employed to simulate the reaction and post-flame zones, adopting different chemical mechanisms. In the simulations reactants enter the reactors at 1000 K, 1 atm and equivalence ratio 0.25. It was observed that mixtures about 3% to 4% in volume of water vapor allow to obtain optimal operation characteristics, including high blowout limit, low ignition delay, maximum reaction zone temperature, high CO2 prodution and low thermal NO formation. It was observed that increasing water contents reduce significantly ignition times up to 3% in volume, while blowout mass flow rates increase continuously up to 6 % in volume, the maximum value considered. Formation of NO decreases continuously with humidity after the flame zone, while there are peaks of NO formation within the flame zone below 1% in volume. Higher water vapor content decreases the final temperatures below 1700 K, leading to a lower thermal efficiency. The method can be used to estimate optimum operational conditions with other input parameters

Aging of Premixed Metal Fiber Burners for Natural Gas Combustion Catalyzed with Pd/LaMnO3·2ZrO2

“…NO originates mainly from the Zeldowich thermal process, [23][24][25] since the CO molecule does not contain N atoms, and when the gas mixture is sufficiently lean (E a ) 20% or more), the formation of radicals CH and HCN is not significant (Fenimore mechanism). [23][24][25][26][27][28][29] Moreover, thermal NO emissions are expected to decrease with lower flame temperatures. Catalytic combustion is operated at lower temperature compared to the conventional flame combustion, thus reducing the formation of thermal NO x , which starts at about 1500 °C.…”

“…In the present case, NO 2 is practically absent. NO originates mainly from the Zeldowich thermal process, − since the CO molecule does not contain N atoms, and when the gas mixture is sufficiently lean ( E a = 20% or more), the formation of radicals CH and HCN is not significant (Fenimore mechanism). − Moreover, thermal NO emissions are expected to decrease with lower flame temperatures. Catalytic combustion is operated at lower temperature compared to the conventional flame combustion, thus reducing the formation of thermal NO x , which starts at about 1500 °C. , This is confirmed by the decreasing trend of NO emissions shown in Figure coupled with the decrease of the temperatures on the burner deck (see Figure ).…”

Energy, Exergy, Economic, and Environmental analysis for various inlet air cooling methods on Shahid Hashemi-Nezhad gas turbines refinery

“…1 Gas turbines are power generation machines that are vastly applied to produce electricity, operate airplanes, ships and for different industrial utilization such as petrochemical plants and refineries. 2,3 Due to the widespread use of gas turbines, the improvement of their performance is very important.…”