Ammonia and hydrogen recovery method

摘要

PROBLEM TO BE SOLVED: To provide a method capable of efficiently recovering ammonia and hydrogen from an exhaust gas containing ammonia, hydrogen, and nitrogen, each of which is discharged from a manufacturing process of a gallium nitride compound semiconductor, and capable of reusing them.SOLUTION: An exhaust gas containing ammonia, hydrogen, and nitrogen, each of which is discharged from a manufacturing process of a gallium nitride compound semiconductor, is subjected to a pressurizing treatment and a cooling treatment using a heat pump to liquefy ammonia contained in the exhaust gas, thereby recovering ammonia from the exhaust gas. Thereafter, the pressurized exhaust gas containing hydrogen and nitrogen is brought into contact with a palladium alloy membrane, and hydrogen having passed through the palladium alloy membrane is recovered.