Gas Application Technologies (Commercial, Industrial Use)

Abstract

We have developed innovative combustion technology for a gas turbine for a cogeneration. This technology can realize a low NOx emission while keeping the flame stable over a wide range of gas turbine operation. The key device is a distinctive part called a fuel-distributing module that switches fuel from a pilot burner to a main and pilot one automatically in accordance to the output of the gas turbine.

Figure and photograph

Diagram of the innovative fuel supply concept by fuel-distributing module

Picture of an example of the prototype combustor

Features

The main burner ensures so-called lean premixed combustion that reduces NOx emissions, while the pilot burner keeps the flame stable. The fuel-distributing module can automatically switch fuel supplied from a single line to the main burner and the pilot one in response to the load change of the gas turbine.
Application of the fuel-distributing module can actualize

Explanation of technical terms

Lean premixed combustion:
Burning technology after mixing fuel with air in advance is called premixed combustion, while by injecting fuel into combustion air and firing them simultaneously is called diffusion combustion. The term of lean combustion is defined as combustion under a lower fuel concentration to equilibrium. Since the fuel concentration is low in a lean premixed combustion, flame temperature cannot become high. Formation of thermal NOx, which is synthesized in large quantities at a high temperature, is accordingly suppressed. However, lean combustion generally has a problem that tends to become unstable.