Method of operating a multi-fuel combustion system

Abstract

The present invention explains a method of operating a multi-fuel combustion system. It consist of a first phase and a second phase, wherein the first phase comprises of providing ignition to a combustor basket to ignite a first type of fuel, where the first type of fuel is supplied to the combustor basket through a first conduit. Also in first phase steam is also supplied to the first conduit in addition to the first type of fuel and steam is supplied to the second conduit after the ignition. In the second phase a second type of fuel is supplied to the combustor basket after ignition of the first fuel through the second conduit, while stopping the supply of the first fuel.

1 . A method of operating a multi-fuel combustion system comprising a first phase and a second phase,
 wherein the first phase comprises:   providing ignition to a combustor basket to ignite a first type of fuel, where the first type of fuel is supplied to the combustor basket through a first conduit;   supplying steam to the first conduit in addition to the first type of fuel and supplying steam to the second conduit after the ignition; and   wherein the second phase comprises:   supplying a second type of fuel to the combustor basket after ignition of the first fuel through the second conduit, while stopping the supply of the first fuel.   
     
     
         2 . A method of operating a multi-fuel combustion system according to  claim 1 , wherein the steam is provided to the second conduit at a time earlier than the steam provided to the first conduit. 
     
     
         3 . A method of operating a multi-fuel combustion system according to  claim 1 , further comprising supplying a medium to the second conduit during the first phase for stabilizing the combustion system for any pressure difference between the second conduit and the combustor basket. 
     
     
         4 . A method of operating a multi-fuel combustion system according to  claim 3 , further comprising shutting off the supply of the medium in the second conduit once the steam supply is stabilized in the first conduit and the second conduit during the first stage of operation. 
     
     
         5 . A method of operating a multi-fuel combustion system according to  claim 1 , further comprising supplying a portion of the second type of fuel to the combustor basket through the first conduit during the second phase. 
     
     
         6 . A method of operating a multi-fuel combustion system according to  claim 5 , further comprising continue supplying the steam in the first conduit from the first phase until the beginning of supplying the portion of the second type of fuel through the first conduit during the second phase. 
     
     
         7 . A method of operating a multi-fuel combustion system according to  claim 5 , wherein the flow of second type of fuel in the second conduit is regulated based on the portion of the flow of the second type of fuel in the first conduit during the second stage of operation. 
     
     
         8 . A method of operating a multi-fuel combustion system according to  claim 5 , wherein the portion of the second type of fuel supplied through the first conduit during the second phase is between 1% and 20% of the total mass flow of the second type of fuel supplied during the operation of the combustion system during the second phase. 
     
     
         9 . A method of operating a multi-fuel combustion system according to  claim 1 , wherein the first type of fuel is natural gas. 
     
     
         10 . A method of operating a multi-fuel combustion system according to  claim 1 , wherein the second type of fuel is syngas. 
     
     
         11 . A method of operating a multi-fuel combustion system according to  claim 1 , wherein supplying the steam into the first conduit and the second conduit starts when the combustion system is loaded between 25% and 40% of its full working capacity. 
     
     
         12 . A method of operating a multi-fuel combustion system according to  claim 1 , wherein supplying a second type of fuel through the second conduit to the combustor basket at the second phase starts when the combustion system is loaded between 30% and 50% of its full working capacity. 
     
     
         13 . A method of operating a multi-fuel combustion system according to  claim 1 , wherein
 at least one of the first type of fuel and the second type of fuel is supplied to the combustion system using a third conduit.   
     
     
         14 . A method of operating a multi-fuel combustion system according to  claim 1 , wherein the combustion system uses a pre-combustion CO 2  capture process.