Fly ash and slag reburning system suitable for coal-fired boiler with horizontally-arranged hearth

Abstract

The invention provides a fly ash and slag reburning system suitable for a coal-fired boiler with a horizontally-arranged hearth. Sufficient burning of pulverized coal fuel is facilitated. A burner isarranged at an inlet of the horizontally-arranged hearth and comprises a center primary air pipe, and the center primary air pipe carries pulverized coal. An outlet of the horizontally-arranged hearthis connected with a flue for discharging smoke. The flue is connected with a recirculation smoke pipeline. An ash bucket communicating with the horizontally-arranged hearth is arranged below the horizontally-arranged hearth. The ash bucket collects slag settled in the horizontally-arranged hearth. The lower end of the ash bucket is connected with a coal mill. The collected slag is fed to the coalmill to be crushed. The recirculation smoke pipeline is also connected with the coal mill. The coal mill is connected with a cyclone separator. Slag powder generated by crushing and recirculation smoke enter the cyclone separator together. An outlet in the upper end of the cyclone separator is connected with an inlet of the center primary air pipe of the burner. The recirculation smoke enters thecenter primary air pipe of the burner together by carrying separated-out qualified fly ash and fine ash.

Description

technical field [0001] The invention relates to a coal-fired boiler with a horizontally arranged furnace, in particular to a fly ash and slag reburning system suitable for a coal-fired boiler with a horizontally arranged furnace. Background technique [0002] The horizontal layout furnace is a type of burner layout furnace commonly used in industrial pulverized coal furnaces. The burners are arranged horizontally. After the pulverized coal and air are sprayed from the burner outlet, they first enter the horizontal layout furnace for combustion, and then enter the vertical furnace to continue combustion. Combustion, exhausted through the flue. Because the industrial pulverized coal furnace generally has a small furnace type and a relatively compact structure, the residence time in the horizontal part of the furnace is short, the temperature is relatively low, and the combustion is not sufficient, and gravity sedimentation occurs during this process, and some fly ash will be d...

AI Technical Summary

Problems solved by technology

However, additional oxygen gauges and thermometers, as well as control systems, are required, increasing cost and system complexity

[0007] The Chinese invention patents with application numbers CN107606606A and CN106247368A only use flue gas recirculation and adjust the amount of recirculated flue gas to achieve low-nitrogen combustion, but they cannot collect the settled fly ash in the horizontal furnace, resulting in fly ash containing High carbon content reduces boiler efficiency

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