Exhaust purification with on-board ammonia production

Abstract

A first aspect of the present disclosure includes a power source for use with selective catalytic reduction systems for exhaust-gas purification. The power source may comprise a first cylinder group with a first air-intake passage and a first exhaust passage, and a second cylinder group with a second air-intake passage and a second exhaust passage. The power source may further include a first forced-induction system in fluid communication with the first air-intake passage, and a second forced-induction system in fluid communication with the second air-intake passage. A catalyst may be disposed downstream of the fuel-supply device to convert at least a portion of the exhaust stream in the first exhaust passage into ammonia.

Description

[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 11 / 412,834, filed Apr. 28, 2006, which is a continuation-in-part of U.S. patent application Ser. No. 10 / 982,921, filed Nov. 8, 2004, both of which are hereby incorporated by reference.U.S. GOVERNMENT RIGHTS [0002] This invention was made with government support under the terms of Contract No. DE-FC05-00OR22806 awarded by the Department of Energy. The government may have certain rights in this invention.TECHNICAL FIELD [0003] This disclosure pertains generally to exhaust-gas purification systems for engines, and more particularly, to selective catalytic reduction systems with on-board ammonia production. BACKGROUND [0004] Selective catalytic reduction (SCR) provides a method for removing nitrogen oxides (NOx) emissions from fossil fuel powered systems for engines, factories, and power plants. During SCR, a catalyst facilitates a reaction between exhaust-gas ammonia and NOx to produce water and nitro...

AI Technical Summary

Problems solved by technology

Because of the high reactivity of ammonia, storage of ammonia can be hazardous.

Further, on-board production of ammonia can be costly and may require specialized equipment.

For example, an engine may function less efficiently and with lower power output when rich combustion occurs in one cylinder group.

Furthermore, using the method of the '542 patent, it may be more difficult to provide adequate and controlled air intake to both cylinder groups, and the two cylinder groups, operating as described in the '542 patent, may cause significant engine vibration.

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