Abstract: A steam soot blowing device is provided, including: a steam sootblower, a first pipe communicating with the steam sootblower; and nozzle assemblies communicating with the first pipe, including a first nozzle assembly and a second nozzle assembly, wherein the first nozzle assembly includes a throttle pipe with one end communicating with the first pipe, and a sprayer communicating with the other end of the throttle pipe, and diameter of an inlet of the sprayer is smaller than diameter of an outlet thereof; the second nozzle assembly includes a distribution pipe communicating with the first pipe and at least one nozzle communicating with the distribution pipe, wherein steam jet velocity at the outlet of the sprayer is greatly smaller than steam jet velocity at an outlet of the nozzle.

Abstract: A dredging device for dredging a pipe is provided including: a carrying frame, adapted to connected to a pipe; a shaking dredging unit including a first shaking plate and a second shaking plate, and the first shaking plate and the second shaking plate are arranged within the pipe; and a driving unit, connected to the carrying frame. The driving unit is connected to the first shaking plate and the second shaking plate for driving the first shaking plate and the second shaking plate to reciprocate to approach or move away from each other.

Abstract: A coal-air synchronous dynamic coordinated control method for a coal-fired unit is provided, comprising: determining functional relationship between unit loads and designed coal feed rates and functional relationship between unit loads and flue gas operation wet-basis oxygen contents, respectively; obtaining a theoretical wet flue gas volume and a combustion-supporting dry air volume per unit mass of burning coal, and calculating an actual combustion-supporting dry air volume per unit mass of burning coal; calculating an actual low calorific value of feed coal; calculating a combustion-supporting dry air volume and an outlet wet flue gas volume; according to the target value of load instruction at a future time point, calculating a coal feed rate variation and a combustion-supporting dry air volume variation; obtaining an operation wet-basis oxygen content variation; and obtaining target values of the coal feed rate and the operation wet-basis oxygen content to be adjusted.

Abstract: A rotary air preheater is provided, including: a rotor and a steam soot-blowing device arranged in a cold secondary air inlet channel of secondary air section. The steam soot-blowing device includes a steam sootblower, a first pipe communicating with the steam sootblower and extending in a radial direction of the rotor, and nozzle assemblies communicating with the first pipe. The nozzle assembly includes a first nozzle assembly and a second nozzle assembly, and the first nozzle assembly is located upstream of the second nozzle assembly in a rotational direction of the rotor. The first nozzle assembly includes a sprayer, and diameter of an inlet of the sprayer is smaller than diameter of an outlet thereof. The second nozzle assembly includes at least one nozzle, and steam jet velocity at the outlet of the sprayer is greatly smaller than steam jet velocity at an outlet of the nozzle.