WORKING GAS CIRCULATION TYPE ENGINE SYSTEM AND ITS OPERATING METHOD

摘要

The present invention provides a working gas-circulating engine system which can suppress NOx emission. The working gas-circulating engine system (1A) comprises: an engine (3) which uses gas whose main component is argon as working gas; a circulation path (5) which connects an exhaust unit (3a) and an air supply unit (3b) of the engine (3) to circulate the working gas; and an oxygen supply device to supply oxygen to the engine (3). The oxygen supply device comprises a low temperature separation device (15) which separates air at a low temperature. An adsorption dehumidifying device (11) is formed on the circulation path (5) to remove moisture from exhaust gas emitted from the engine (3). A low pressure nitrogen supply line (17) discharges nitrogen separated by the low temperature separation device (15), and nitrogen induced from the low pressure nitrogen supply line (17) is used as regenerative gas of an adsorbent of the adsorption dehumidifying device (11).