Abstract: A method for reducing emissions of oxides of nitrogen from a combustion process using a temperature sensitive liquid reagent injected into a stream of exhaust gases from the combustion process and passing the exhaust gases and the reagent through a catalytic reactor which reduces the oxides of nitrogen in the presence of the reagent is disclosed. The steps of the method include providing an injector having an orifice for atomizing the liquid reagent; positioning a portion of the injector having the orifice within the stream of exhaust gases; cooling the injector by continuously circulating the reagent therethrough, thereby keeping both the injector and the reagent within the injector below a critical temperature at which the reagent will solidify; and injecting a portion of the reagent into the exhaust stream upstream of the reactor.

Abstract: An injector for delivery of a fluid into a stream of hot gas is disclosed. The injector has a valve body with an elongated chamber in fluid communication with an orifice. A valve seat surrounds the orifice. A valve plunger is disposed within the chamber, an end of the plunger being adapted to sealingly interengage the seat. The plunger is slidably movable between an open and a closed position to open and close the orifice. A fluid inlet and an outlet are disposed within the valve body to deliver fluid to an annular fluid passageway in the chamber adjacent to the valve seat. Fluid is circulated through the annular passageway to cool the valve and a portion of the fluid is expelled through the orifice when the orifice is opened. The plunger is biased into the closed position by a coil spring and movable into the open position by a solenoid actuator mounted atop the valve body.

Abstract: The invention provides means for controlling the rate of fuel injection of an accumulator injector of the type employing a pressure amplifying piston assembly. In one form of the invention, the injection rate is controlled by restricting the pressure decay in the amplifier chamber. In another form of the invention, means are provided for delaying the full opening of the injector valve needle after an initial valve opening.