Large-scale circulating fluidized bed boiler

A large-size circulating fluidized bed boiler, comprising:

• a furnace having a vertical furnace center line;
• and
• at least two groups of cyclones, each cyclone of each group of cyclones having an inlet gas pass communicated with the furnace,
• wherein a furnace cross section formed by outer sidewalls at the inlet gas pass of the cyclone is a polygon having 2×n sides, and n is a positive integer greater than 1;
• wherein the polygon is axially symmetric with respect to a perpendicular bisector of each side of the polygon, and when n is 2, the polygon is a square;
• further comprising:
• a water cooling column disposed at the furnace center line and extending from an air distributor to a ceiling, wherein the outer sidewalls of the furnace, the water cooling column, the ceiling and the air distributor together enclose a furnace combustion space;
• and wherein the water cooling column is a column surface formed by enclosing water walls;
• wherein a single flow field in communication with each of an inlet of the inlet gas pass of each cyclone is formed in the cross section, the single flow field indicates that the cross section is not divided into a plurality of sub-blocks that are not fluidly communicated with each other in the plane of the cross section;
• wherein the at least two groups of cyclones are arranged by a same interval angle about the furnace line;
• and
• wherein the respective sides of the cross section at the respective groups of cyclones are equal to each other,
• wherein outer sides of the inlet gas passes of two cyclones of each group of cyclones are adjacent to each other and close to a center of the respective outer sidewall, and inner sides of the inlet gas passes of two cyclones of each group of cyclones face toward two corners of the outer sidewall,
• the cross section of the water cooling column exhibits a polygon mated with the shape of the cross section of the furnace outer sidewalls, wherein the number of sides of the polygon formed by the cross section of the water cooling column is equal to the number of sides of the polygon formed by the furnace cross section.