| 摘要 |
PROBLEM TO BE SOLVED: To provide a coal gasification system which improves efficiency of a plant by making adjustable a ratio of carbon monoxide to hydrogen in product gas produced in a gasifier by a shift reaction of a shift reaction installation.SOLUTION: A coal gasification system comprises a drier which dries coal with flue gas to cause moisture in the coal to be contained in the flue gas, a gasifier which produces product gas by gasifying the coal, a dust removal unit which removes fine particles in the product gas in the gasifier, a condensation heat exchanger which cools the flue gas after drying of the coal in the drier to condense moisture in the flue gas to liquid water, a water recovery tower which introduces the flue gas having passed through the condensation heat exchanger and condensed water to recover water from the flue gas, a water supply system which introduces the water recovered from the flue gas in the water recovery tower to the condensation heat exchanger, raises the temperature through indirect heat exchange and supplies to the gasifier and a shift reaction installation which introduces the product gas after removal of fine particles in the dust removal unit and water vapor and causes the shift reaction of carbon monoxide with water vapor in the product gas so as to convert into carbon dioxide and hydrogen. |
