A gasification system including a gasifier, a feed injector, and a fuel feed system that includes a first feed line, a second feed line, and a controller that includes a processor. The processor is programmed to enable the first feed line to supply a fuel gas into the feed injector, enable the second feed line to supply oxygen into the feed injector, receive instructions to add a slurry to the gasifier, prevent the first feed line from supplying the fuel gas into the feed injector, enable the first feed line to supply the slurry into the feed injector, enable the second feed line to simultaneously supply the oxygen and the inert gas into the feed injector, and prevent the second feed line from supplying the inert gas into the feed injector.