Denitrification of engine exhaust gas without adding reducing agent - by adsorption in adsorber in exhaust pipe, periodic desorption with hot gas and recirculation to combustion in suction air supply

摘要

Redn. of NOx in engine exhaust gas (I) involves adsorption of NOx in an adsorber in the exhaust pipe, periodic desorption with a hot gas (II) and then reaction to N2 and O2. The novelty is that the NOx is mixed with the suction air for reaction in the combustion chamber of the engine. NOx is adsorbed and desorbed alternately in 2 parallel adsorbers. The hot gas from the adsorber can be used for desorption. For a compression engine with a catalyst in the exhaust pipe, excess air is used in the adsorption phase and an approx. stoichiometric mixt. for the desorption phase and a small amt. of the exhaust gas stream is passed to the adsorber in the desorption phase, whilst the rest passes directly to the catalyst. ADVANTAGE - NOx is reduced without using added reducing agent and the entire operation is confined to the engine.