What is the working principle of the pulverized coal burner?
Pulverized coal burner refers to the equipment that can fully burn pulverized coal in a short period of time and produce high temperature eddy current.According to the use, pulverized coal burner is divided into: 1, pulverized coal burner for rotary kiln;2. Pulverized coal burner for boiler;3, asphalt mixing station special pulverized coal burner.
As a representative of the advancement of scientific and technological inventions, pulverized coal burners combine two contradictory technologies to create a new technology. So do you understand the working principle of pulverized coal burners and what are the classifications of pulverized coal burners?
The working principle of the pulverized coal burner:
The basic principle of plasma ignition technology is to directly ignite pulverized coal with a high-power arc. The ignition device uses direct current (greater than 200 A) to initiate arc through yin and yang contact under the condition of medium pressure greater than 0.01 MPa, and obtains a stable power direct current air plasma under a strong magnetic field. Its continuously adjustable power range is 50-150 kW, and the intermediate temperature can reach 6000 ℃.
The primary air powder is sent to the plasma ignition pulverized coal burner after the concentration is separated, so that the dense-phase pulverized coal enters the middle area of the plasma torch, and ignites quickly within about 0.1s, and provides a high-temperature heat source for the light-phase pulverized coal to make the light-phase pulverized coal It also catches fire quickly, and then forms a stable burning torch. The burner wall adopts gas film cooling technology, which can cool the burner wall to prevent burning damage and slagging. The electricity and coils are cooled with demineralized water.
Classification of pulverized coal burners:
Common pulverized coal burners are divided into two types: direct flow and swirling. The outlet of the direct-flow pulverized coal burner is composed of a set of nozzles in rectangular, circular or polygonal shapes. The primary air carrying pulverized coal, the secondary air for combustion and the exhaust gas (tertiary air) of the pulverized coal are all passed in a direct current form. The respective nozzles enter the furnace.
In general, direct-flow burners cannot be combusted individually, and need to be combined with other burners arranged at four corners to form an imaginary tangent circle on one or two axes in the middle of the furnace to form the combustion middle area. The outlets of the swirl burners are all round, the primary air can be direct current or swirling into the furnace, and the secondary air rotates around the burner axis into the furnace in the form of swirling to achieve the purpose of full mixing of air and powder. The swirl burner can burn independently. Since its outlet is round, it is also called a round burner.
