CFB boiler external bed partition wall, cooling system and operation method

Abstract

The invention discloses a CFB boiler external bed partition wall, a cooling system and an operation method. The CFB boiler external bed partition wall comprises strip-shaped heat dissipation platse and two walls, wherein the walls are arranged in the vertical direction, a heat dissipation space is formed between the walls, the top of the heat dissipation space is sealed, a plurality of strip-shaped heat dissipation plates are arranged in the heat dissipation space, the strip-shaped heat dissipation plates are tightly connected with the inner side faces of the walls, the two adjacent strip-shaped heat dissipation plates are provided with intervals, the strip-shaped heat dissipation plates and the walls form airflow channels, and the outer side surfaces of the walls are each provided with arefractory layer; air boxes are arranged at the two ends of the partition wall respectively, an air chamber is arranged below air distribution plates on the two sides of the partition wall, the partition wall, the air chamber and the two air boxes communicate to form the airflow channel, and the airflow channel communicates with a high-pressure fluidizing air mother pipe. According to the CFB boiler external bed partition wall, high-pressure fluidizing air can be used as a cooling medium, no additional peripheral equipment is required, the system is simple in structure, and if the partition wall fails, fault isolation can be achieved by online switching status, and expansion and collapse of the partition wall are avoided; and the high-pressure fluidizing air can further be recycled to continue to use, and the cost is saved while the partition wall is effectively cooled.

Description

technical field [0001] The invention belongs to the technical field of circulating fluidized bed (CFB) boiler power generation, and in particular relates to an external bed partition wall of a CFB boiler, a cooling system and an operation method. Background technique [0002] With the rapid development of the large-scale trend of CFB boilers, in order to make up for the problem of insufficient heating surface, external heat exchangers (external beds) have become an important part of large CFB boilers. CFB boilers are usually arranged with 4 to 6 external beds, and the partition wall divides each external bed into several air chambers to achieve different functions. The temperature of each air chamber is between 800 and 1000 °C. The traditional external bed partition is made of steel bars bundled into a skeleton, and then covered with a refractory layer. Long-term operation, the high temperature makes the steel skeleton expand, and the partition wall is squeezed by the four ...

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Problems solved by technology

[0003] In order to overcome the defects of the above-mentioned prior art, the present invention provides a CFB boiler external bed partition wall, cooling system and operation method, which can reduce the operating temperature of the partition wall, and if the partition wall fails, the fault isolation can be realized by switching the valve state online; Avoid the expansion and collapse of the partition wall, so as to solve the problem of thermal collapse of the external bed partition wall in the prior art

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