Composite-bed low circulation fluidized bed boiler

Abstract

The invention is a composite bed type low range circulating fluid bed boiler. A tower structure is used; multiple layers of fluid bed combustion chambers are installed along the height of a furnace chamber; the combustion chambers are internally provided with embedded pipe heating surfaces; each layer of combustion chambers can independently run; and low fluid wind speed is used for reducing abrasion of flame retardant coating and heating surface and reducing the operation power consumption of the boiler. A reheater, a superheater and a coal economizer are respectively installed inside the furnace chamber. The upper part of the outlet of the boiler furnace chamber is provided with a horizontal air preheater, and a low-temperature gas-solid cyclone separator is installed at the rear of the horizontal air preheater; fly ash matters separated are fed in a return conveyor of fly ash matters through a ash bucket and feed legs thereof, and are then fed in the fluid bed combustion chambers so as to form circulating combustion of fly ash. The fly ash matters separated from the low-temperature cyclone separator is very low, and the problems of reburning scorification and blockage of feeding material cannot occur, thereby greatly improving the reliability of fly ash circulating system.

Description

technical field [0001] The invention relates to the technical field of boilers, in particular to a composite bed type low rate circulating fluidized bed boiler. Background technique [0002] As a clean coal combustion technology, circulating fluidized bed combustion technology has many advantages, such as: (1) It can realize medium-temperature combustion, is suitable for direct desulfurization in the combustion process, and has high desulfurization efficiency. At the same time, due to the low combustion temperature, its nitrogen oxide emission is low; (2) The heat capacity of the bed material is large, which can effectively burn inferior coal or other solid fuels, and the combustion efficiency is high; (3) The load regulation performance is good, and the operation is simple ; (4) It can be used for thermal standby, and when the bed temperature is greater than 650°C, it can be directly fed into coal for hot start; (5) The fuel preparation system is simple; (6) The discharged ...

AI Technical Summary

Problems solved by technology

It can effectively solve the serious wear and tear of the furnace refractory layer and heating surface, high operating power consumption, poor boiler output stability, and failure rate in circulating fluidized bed boilers that adopt a high fly ash material circulation rate in order to achieve large-scale. High and difficult to solve problems, and has the advantages of reliable operation, high thermal efficiency and low energy consumption

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