Minimising nitrogen oxide cpds. emission from engine or furnace - using agent subjected to chemical and/or physical pretreatment, avoiding need for catalyst

摘要

Minimising NOx in the combustion of a fuel in an i.c. engine and/or furnace uses substance(s) (I) subjected to chemical and/or physical pretreatment so that they cause a chemical and/or physical reaction with NOx. Pref. (I) reacts with NOx in any spot in the engine or furnace or in the exhaust gas stream. (I) pref. is injected into the exhaust gas, so that intensive mixing occurs, or injected into the engine or furnace. Pref. (I) is an amine, which is passed through a catalyst so that an active species forms; or (I) is subjected to catalyst treatment, before or after chemical and physical treatment. USE/ADVANTAGE - The process is very economical, since the gas is not treated with catalyst and the efficiency is not affected by different operating states of the plant, e.g. can operate at exhaust gas temps. between O and 1000 deg. C. Only relatively small amts. of (I) are needed, hence the equipment can be very small and cheap