Optimization of purge process before ignition of natural gas turbine

Abstract

In order to achieve the target of low power consumption of the plant and quick start-up in the ignition phase of the peak-regulating natural gas turbine， the feasibility of canceling purge before ignition of natural gas turbine is studied considering of the actual working conditions of the unit and the existing industry standards of natural gas turbines. Through the analysis of geometric structures of the exhaust passage and the connecting part of heat recovery boiler， a layout strategy of natural gas monitoring system considering both sampling safety and data reliability is proposed. Take Ansaldo AE94.3A natural gas turbine in a power plant as an example， the purge process before ignition of natural gas turbine is analyzed， the elastic purging scheme based on concentration judgment for natural gas is proposed and process flows under abnormal working conditions， such as ignition failure， trip of natural gas turbine and human intervention are optimized. The analysis of the start-up curve of the unit before optimization shows that， the start-up time of the natural gas turbine can be reduced to a certain extent， the power consumption of the plant can be reduced， and the heating effect of the steam turbine can be improved after the optimization of the purge process.

Keywords

• peak-regulating natural gas turbine
• power consumption of plant
• quick start-up
• purge before ignition
• concentration judgment of natural gas