Dual-fluid spraying gun structure suitable for flue-type urea direct injection pyrolysis process

Abstract

The invention discloses a dual-fluid spraying gun structure suitable for a flue-type urea direct injection pyrolysis process. The dual-fluid spraying gun structure comprises a gun barrel and an atomizing nozzle, wherein the gun barrel comprises a cooling air pipeline, an atomizing air pipeline and a urea solution pipeline; the urea solution pipeline, the atomizing air pipeline and the cooling air pipeline are distributed from inside to outside in sequence; a side face of one end of the cooling air pipeline is provided with a cooling air inlet; a side face of one end of the atomizing air pipeline is provided with an atomizing air inlet; the atomizing nozzle is fixed on a side face of the other end of the cooling air pipeline; an atomizing air inlet of the atomizing nozzle is connected with the other end of the atomizing air pipeline; a urea solution inlet of the atomizing nozzle communicates with the urea solution pipeline; an outer wall of the cooling air pipeline is provided with a heat-insulating layer; the heat-insulating layer is positioned in a flue. By adopting the structure, the cooling air volume of a dual-fluid spraying gun for the urea direct injection pyrolysis process can be effectively lowered, the urea solution in the gun barrel can be kept in a liquid state, and a urea direct injection pyrolysis spraying gun has a good atomizing effect.

Description

technical field [0001] The invention relates to a dual-fluid spray gun structure, in particular to a dual-fluid spray gun structure suitable for a flue-type urea direct injection pyrolysis process. Background technique [0002] In the SCR denitration technology, liquid ammonia or urea is usually used to prepare the reducing agent required for the SCR denitration reaction. Since liquid ammonia is a toxic and dangerous chemical, in recent years, the SCR denitrification technology using urea as a reducing agent has been widely used. Using urea to prepare reducing agent, there are three relatively mature technologies: traditional urea pyrolysis technology, urea hydrolysis technology and urea flue direct injection pyrolysis technology. Urea pyrolysis requires the use of electric heaters or high-temperature flue gas heat exchangers to heat the hot primary air to 500-600°C and send it into the pyrolysis furnace to pyrolyze the urea solution to obtain the reducing agent for the SCR...

AI Technical Summary

Problems solved by technology

After calculation, if air cooling is used alone, the flow of cooling air is more than twice the flow of atomizing air. The user needs to configure the air compressor system separately to provide cooling air, which increases the initial investment cost and operating power consumption of the system.

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