Multistage plunger adjusting device for slag discharge of fluidized bed boiler

Abstract

The invention discloses a multistage plunger adjusting device for slag discharge of a fluidized bed boiler. The device comprises a slag discharge pipe 1, a plunger 2, a plunger 3 vertically intersected with the plunger 2, a sealing ring 4, an asbestos filler 5, a limit pin 6, a limit U-shaped ring 7, an operating handle jack 8 and an asbestos filler sealing gland 9. The plunger 2 and the plunger 3 are made of heat and abrasion resistant round steel, and the parts of the plungers exposed outside the slag discharge pipe are made of carbon steel. The plunger group of each stage consists of the plunger 2 and the plunger 3 which are mutually vertical. The plunger groups of multiple stages are combined into the multistage plunger adjusting device, and the flow of slag particles is adjusted by changing the number and the inserting depth of the plungers inserted into the slag discharge pipe. The flow of the slag particles is reduced by means of the plunger groups of multiple stages rather than only the flow of the slag particles is adjusted by changing the flow section. The two adjacent plunger groups are staggered up and down for 45 degrees in the horizontal direction. The dynamic and static clearances of the plungers are reliably sealed by the sealing ring 4, the asbestos filler 5 and the asbestos filler sealing gland 9.

Description

technical field [0001] The invention relates to a circulating fluidized bed boiler, in particular to a multi-stage plunger adjusting device for slag discharge of the fluidized bed boiler. Background technique [0002] my country is currently the country that uses the most circulating fluidized bed boilers (CFB boilers) in power plants in the world. There are more than 3,000 large and small circulating fluidized bed power plant boilers in operation, including large circulating fluidized bed power plant boilers with a capacity of 410t / h or more. There are more than 140 sets, and there are more than 20 sets of large-scale circulating fluidized bed power plant boilers above 1025t / h (more than 50 sets are under construction). [0003] The furnace of the circulating fluidized bed boiler in the power station has a four-sided furnace wall structure with a cone in the lower part and a rectangular column in the upper part. The slag discharge port is arranged at the part of the lower co...

AI Technical Summary

Problems solved by technology

Production practice has proved that when the slag is fine, the slag has a strong fluidity, and the flow rate of the slag discharge is still large even if the speed of the slag cooler is very low. The control of the material layer thus affects the normal operation of the boiler

[0004] Uncontrolled slag flow can also lead to clogging of the slag cooler

[0005] Traditional control valves that change the size of the flow section in one section are not suitable for the regulation of fluidized bed boiler slag discharge. Changes in the size of the flow section will cause large particles to block the slag discharge pipe or cause slag flow to be lax due to slag inclusions

Cone valves were mostly used for the slag discharge flow of early circulating fluidized bed boilers. Production practice has proved that slag blocks are easy to get stuck in the gaps of the cone valves, but the fine slag particles are still flowing, causing the slag flow to be out of control or not closed tightly.

In addition, the price of the cone valve is as high as 700,000 to 800,000 yuan.

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