Lateral air distribution hot ash return flow control device and method capable of realizing double adjustment of bed temperature and steam temperature

Abstract

The invention discloses a lateral air distribution hot ash return flow control device and method capable of realizing double adjustment of bed temperature and steam temperature, the device comprises four small-sized hot ash return devices which are respectively provided with unequal heating surfaces, the amount of ash falling into each device is adjusted by utilizing lateral blowing air at the bottom of a downcomer and an auxiliary bed, and the ash is smoothly blown into each main bed, so that the hot ash return flow is controlled. And blockage or reverse flowing of hot ash is avoided. A partition plate in the main bed divides the main bed into a first main bed chamber and a second main bed chamber which are respectively provided with a heating surface, a passage between the two chambers is reserved at the top and the bottom of the partition plate, hot ash can flow conveniently, and the hot ash flowing out of each material returning pipe is converged into a material returning main pipeline to return to a hearth after heat exchange. The heat absorption capacity and the ash temperature of the pipe bundle can be effectively regulated and controlled, then the bed temperature is regulated, and double precise regulation and control of the bed temperature and the smoke temperature are achieved; various heat exchangers can be arranged, the heating surface is prevented from being corroded by high-temperature flue gas such as SO2 and HCl and accumulated ash when being arranged at the tail flue, stable operation can be achieved, the operation and maintenance cost can be reduced, and the heat exchanger is suitable for the circulating fluidized bed garbage incinerator.

Description

technical field [0001] The invention belongs to the design field of external heat exchangers of circulating fluidized bed waste incineration boilers, and particularly relates to a hot ash return flow control device and method capable of realizing double adjustment of bed temperature and steam temperature with lateral air distribution. Background technique [0002] Due to its good adaptability to waste components, circulating fluidized bed boilers have been gradually applied to the harmless treatment of domestic waste in recent years. With the increase of boiler capacity and specifications, the furnace and tail flue cannot provide enough heating surface, so it has become the current development trend to arrange part of the heating surface in the external heat exchanger. The external heat exchanger can effectively adjust the flow rate of the ash back to the furnace, so as to flexibly adjust the heat absorption of the furnace temperature and the internal heat exchanger; and the...

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Problems solved by technology

[0006] The main purpose of the present invention is to overcome the deficiencies of the prior art, and provide a hot ash return flow control device and method for lateral air distribution that can realize double-adjustment of bed temperature and steam temperature, so as to solve the problem of external heat exchange of existing waste incinerators. During the operation of the boiler, it is easy to have problems such as ash accumulation, reverse channeling, etc., which cannot realize effective heat exchange, affect the ash circulation, and realize the bed temperature adjustment and the normal operation of the boiler as a whole. The present invention controls the hot ash return flow The device is set as an axisymmetric cross-shaped structure, and the design of inclined surface and lateral air distribution is added. In addition, a partition arranged at the middle height is set up, so that the hot ash return is connected to the upper and lower ends of the partition. The passages of the two chambers of the flow control device can effectively adjust the flow rate of high-temperature circulating hot ash, the heat absorbed by the external heat exchanger and the bed temperature. In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

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