Cold start method for circulating fluidized bed boiler

Abstract

The invention discloses a cold start method for a circulating fluidized bed boiler, sequentially comprising the following steps of: filling the main bed of a hearth with an inert bed material; carrying out a material level test for the bed material on the main bed; carrying out a fluidization test for the bed material on the main bed; lighting an oil gun at a critical fluidized air volume, and starting to heat the bed material; regulating the output of a primary air fan, heating the bed material at a solid bubble air volume, regulating the output of the oil gun, and heating the bed material up; when the temperature of the bed material reaches a coal feeding temperature, regulating the output of the primary air fan, and ensuring a primary air volume that is not lower than the critical fluidized air volume; and feeding coal into the hearth through a coal feeding port, and stopping the oil gun, thus finishing cold start for the combustion side of the boiler. The bed material is heated up in a static bed state through primary air with the solid bubble air volume; the air volume is low, so the cold start consumes low power and low fuel oil, and costs short time, and reasonable particle size distribution of the bed material can be realized; and the cold start method for the circulating fluidized bed boiler disclosed by the invention can ensure the safety of the boiler, reduce cold start time and obviously reduce energy consumption.

Description

technical field [0001] The invention relates to an operation method for running the combustion side of a circulating fluidized bed boiler, in particular to a method for starting the combustion side of the circulating fluidized bed boiler in a cold state. Background technique [0002] Circulating fluidized bed boiler (circulating fluidized bed boiler abbreviation CFBB) technology is a high-efficiency, low-pollution and clean boiler combustion technology that has developed rapidly in the past ten years. At present, this technology has been widely used in the fields of power station boilers, industrial boilers and waste treatment and utilization, and is developing towards large-scale circulating fluidized bed boilers with a scale of one million megawatts. In China, it is a 300MW turbogenerator set The application of supporting 1065 T / H circulating fluidized bed boilers is gradually increasing, and the next few years will be an important period for the rapid development of circu...

AI Technical Summary

Problems solved by technology

[0012] In the cold start-up of this kind of circulating fluidized bed boiler, the whole process is to use the primary air of not less than the critical fluidization air volume to heat the bed material in the fluidized state. The air volume is large, and the power consumption of cold start-up is high. , the time is longer, and the fuel consumption is larger; when the bed material is heated in the fluidized state, the fine bed material will be lost as the flue gas is discharged from the furnace, and the loss of the fine bed material will destroy the bed material particles. Reasonable distribution of coal diameter makes it difficult to feed coal. In severe cases, it is necessary to stop the furnace and refill the bed material, which greatly affects the cold start process of the boiler and prolongs the cold start time of the boiler.