Ammonia gas generation metering spraying device with short response time and spraying rate control system

Abstract

The invention discloses an ammonia gas generation metering spraying device with short response time and a spraying rate control system. The ammonia gas generation metering spraying device with short response time comprises a metering spraying control unit, a hollow large container with an ammonia generation chamber, a cover, a solid-state reducing agent, an electric heater, a liquid discharging pipeline, a heat exchanger, a cooling liquid passage connected with the heat exchanger through a control valve, a gas releasing pipe uniformly provided with openings, a hollow small container which communicates with the ammonia generation chamber through a check valve and a middle pipeline and is provided with a buffering cavity, a secondary electric heater, an exhausting passage which communicateswith the buffering cavity through an electric control valve and an exhausting pipeline and is used for exhausting ammonia gas, and an electric heating line located in the exhausting pipeline and the middle pipeline. A first pressure sensor and a first temperature sensor are arranged in the buffering cavity. A second temperature sensor is arranged in the ammonia generation chamber. Driving signalsof the secondary electric heater are voltage pulse signals with high current signals and low current signals. The ammonia gas generation metering spraying device with short response time and the spraying rate control system can accurately control the release speed of ammonia.

Description

technical field [0001] The present invention relates to an ammonia gas generating and conveying device and an injection rate control system, in particular to an ammonia gas generating metering injection device and an injection rate control system with a short response time. Background technique [0002] Selective catalytic reduction (SCR) technology has been widely used to reduce NOx emissions from internal combustion engines, especially diesel engines. In an SCR system, it is generally necessary to mix ammonia (NH3) with the exhaust of the engine and then pass it through a catalyst where the ammonia reacts with NOx in the exhaust and reduces the NOx to nitrogen and water. Due to safety concerns and difficulties in transportation and storage, in SCR systems, ammonia is usually generated from precursors (such as urea) rather than used directly. Precursors are also referred to herein as reducing agents. [0003] Both solid and liquid reductants can be used in SCR systems. S...

AI Technical Summary

Problems solved by technology

Therefore, when using these ammonium salts as reducing agents, if only the mass flow rate of the effluent is controlled, the inaccurate metering and injection will also be caused due to changes in the content of ammonia therein.

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