The system starts with a gasifier in which pulverized coal is mixed with water and partially burned at low temperatures (1,370ºC) to release hydrogen and carbon monoxide. The remaining ash solidifies to a nontoxic glasslike slag that can be disposed of in a landfill. Captured heat is used to generate steam that drives electric generator turbines. The cool synthetic gas (syngas) passes through scrubbers that convert hydrogen sulfide gas (H2S) to elemental (solid) sulfur. Clean syngas is burned in a gas turbine to generate more electricity, and still more heat is captured to make high-pressure steam to run turbo generators. The overall efficiency of this integrated system can approach 40 percent.