Turbine exhaust fed low NO.sub.x staged combustor for TEOR power and steam generation with turbine exhaust bypass to the convection stage

摘要

In a low NO.sub.x power and steam generator for thermally enhanced oil recover, a gas turbine fired with nitrogen-bearing crude oil and air produces power and hot turbine exhaust. A portion of the turbine exhaust is fed into the primary combustion chamber of a two-stage combustor for supplying the combustion air for burning a high nitrogen- containing crude oil in the primary combustion zone under fuel-rich conditions. The combustion is completed in a secondary combustion zone supplied with air derived from a second portion of the turbine exhaust at about 1200° F. A third portion of the turbine exhaust is fed into a convection stage disposed to receive the exhaust from the secondary combustion zone for capturing the heat from the turbine exhaust and from the exhaust of the secondary zone and converting it to steam. The output exhaust flow from the turbine is relatively constant with time, whereas the steam requirements for oil recovery decrease with time as production falls off and, thus, means are provided for bypassing an increasing percentage of the turbine exhaust around the two-stage combustor for heat recovery in the convection stage.