Flue-gas swirl strong mixing split filter board

Abstract

A flue gas swirl strong mixing diversion filter board is used in a power station pulverized coal fired boiler at a grizzly screen for spraying ammonia of a flue gas selective catalyctic reduction (SCR) denitration device; the swirl strong mixing diversion filter board (4) are arranged along the outer surface of a metallic conduit (2) of the grizzly screen for spraying ammonia and is divided into an upper board and a lower board, the lengths of which are equal to or slightly longer than that of a spray pipe; the swirl strong mixing diversion filter board (4) installed on the metallic conduit (2) of the grizzly screen for spraying ammonia is close to an ammonia gas jet orifice (3) and forms the angle of 40-60 degrees, and the upper board and the lower board of the swirl strong mixing diversion filter board (4) are symmetrical and connected and supported with each other by a filter board support (5). The ammonia gas is gradually mixed with the flue gas in the process of flowing along the filter board (4) and gradually flows into flue gas flow field at rear along a round hole to be diverted by the round hole. The mixture of the ammonia gas and the flue gas form a great deal of swirl under the action of an ostiole of the filter board and the sawtooth edge of the filter board, and is rapidly mixed in the flow.

Description

technical field [0001] The invention relates to a flue gas vortex strong mixing shunt filter plate used in a flue gas selective catalytic reduction (SCR) denitrification device used in a pulverized coal boiler of a power station, and belongs to the technical field of environmental protection equipment. Background technique [0002] Selective catalytic reduction (SCR) is mainly used to remove NOx in flue gas. At present, SCR technology has been widely used in various industrial devices such as power plant boilers and gas turbines due to its stable performance and good removal efficiency. At present, the most commonly used arrangement method of SCR is high-dust arrangement, that is, it is arranged after the economizer and before the air preheater. The main principle is to use liquid ammonia or ammonia water as a reducing agent, mix it with air and spray it into the flue upstream of the SCR reactor, and react with NOx in the flue gas under the action of a catalyst to generate ...

AI Technical Summary

Problems solved by technology

Even so, ammonia and flue gas cannot meet the mixing requirements at the ammonia injection grid, and a static mixer is still required downstream, making the length of the mixing section very long, and the distance between the economizer and the air preheater is limited. Therefore, it is usually necessary to add a turning section to meet the mixing requirements, which greatly increases the volume of the SCR device and brings inconvenience to the design, installation and operation of the device

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