An air-cooled slag drying machine slag sensible heat recovery system

Abstract

The invention relates to a slag sensible heat recycling system for an air-cooling dry slag machine. A horizontal segment, close to one side of a lifting segment, of the dry slag machine is provided with a shutter rotation opening-closing mechanism air inlet; the side, away from the lifting segment, of the air inlet is provided with an isolating device; the position, on the inner side of the top ofan outer shell, close to a joint of the dry slag machine and a boiler is provided with a temperature sensor; and the outer wall of the outer shell is provided with a controller, and the top of the dry-slag-machine lifting segment in the air-cooling dry slag machine is connected with a second air preheater and a first air preheater correspondingly through air pipes. The slag sensible heat recycling system for the air-cooling dry slag machine is reasonable in design, the influence of cold air on the operation of the boiler can be effectively avoided, the slag cooling efficiency is improved, meanwhile the slag sensible heat is used sufficiently, the low temperature corrosion environment of the air preheaters is improved, the tail gas temperature of the boiler is raised, at the same time theheat can be recycled by a low temperature economizer to raise the feed-water temperature, the total air volume entering the boiler is controlled, the low nitrogen combustion and low oxygen combustionare achieved, the discharging of NOX from boiler combustion is lowered, the amount of ammonia spraying in SCR area is reduced, and the efficiency of the boiler is improved.

Description

technical field [0001] The invention relates to the technical field of dry slag discharge at the bottom of a coal-fired boiler in a power plant, in particular to an air-cooled slag drying machine slag sensible heat recycling system. Background technique [0002] The air-cooled dry slag removal system is the continuous operation of the air-cooled steel belt machine, the high-temperature slag continuously falls on the conveyor belt, and the high-temperature ash moves on the conveyor belt at a low speed. Under the action of negative pressure, a small amount of controlled ambient cold air enters in reverse The inside of the air-cooled dry-type slag remover makes the ash and slag gradually cooled by the wind on the conveying steel belt, and gradually completes the combustion. The cold air and the high-temperature slag conduct sufficient heat exchange. The air absorbs the radiant heat of the boiler and the sensible heat of the slag. The temperature drops to about 100-200°C. [0...

AI Technical Summary

Problems solved by technology

[0004] The air inlet device of the traditional air-cooled dry slag machine is to open a hole outside the shell of the dry slag machine, install an air inlet with adjustable air intake, and the inside of the shell is open. The disadvantage of this air inlet is that the cold air enters the shell Finally, it will return to the boiler furnace from the gap where the resistance is the least. Since part of the cold air does not pass through the heat exchange of the dryer conveyor belt, the efficiency of cooling slag is very low, which also affects the normal operation of the boiler.

At the same time, the sensible heat of slag in the existing dry slag removal system has not been effectively utilized, resulting in a great waste of heat

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