Method and process of producing ammonia from methane hydrate

Abstract

The present invention discloses a method and a process of producing ammonia from methane extracted from methane-hydrate at the site of methane-hydrate extraction. The method and the process comprise coupled chemical reactions. During the first reaction, carbon dioxide reacts methane-hydrate to produce carbon-dioxide-hydrate and methane: carbon dioxide+methane-hydrate⇄carbon-dioxide-hydrate+methane (CO+CH-hydrate⇄CO-hydrate+CH). The produced methane is reacted with water to produced carbon dioxide and hydrogen via the second reaction: methane+water⇄carbon dioxide+hydrogen (CH+2HO⇄CO+4H). One embodiment of the second reaction is a combination of the methane steam reforming reaction (CH+HO⇄CO+3H) and the water-gas shift reaction (CO+HO⇄CO+H), both are widely known in the art. The carbon dioxide produced in the second reaction is recycled and used for the first reaction. The hydrogen produced in the second reaction is reacted with nitrogen produced from an air separation process that is known in the art to produce ammonia via the third reaction: nitrogen+hydrogen→ammonia (N+3H→2NH). One embodiment of the third reaction is the well-known Haber-Bosch process. The current invention is related to co-locating the ammonia synthesis at the methane-hydrate extraction sites to minimize the cost of transporting both methane and carbon dioxide over long distances. The process and the associated method also have the advantage of on-site carbon sequestration. The ammonia product produced via the current invention is easily transportable in liquid form from the production sites to the end-use sites as a carbon-free liquid fuel, a fertilizer and a chemical feedstock.