Plants D with modification of the oxidant in combustion

In conventional cycles, combustion is the major source of irreversibility, leading to reduction in thermal efficiency. Some novel plants involve partial oxidation (PO) of the fuel in two or more stages, with the temperature increased before each stage of combustion, and the combustion irreversibility consequently reduced. In other plants full oxidation is employed which makes CO2 removal easier. 

Six cycles with oxidant modification are listed as D1 the simple PO open CBT cycle—involving staged combustion of the fuel  

D2 the PO open CCGT cycle—involving. staged combustion of the fuel and low pressure CO2 removal  

D4 the semi-closed CBT or CCGT plant with full oxidation—oxygen supplied to the combustion chamber instead of air, with CO2 removal at low pressure level  

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