This document provides a summary of the key components of a circulating fluidized bed (CFB) boiler, including: the wind box and grid nozzle for distributing air, bottom ash drain, high pressure blowers, cyclone separators, evaporative/superheat walls, fuel and limestone/sand feeding systems, refractory lining, solid recycle loop seals, wall tubes, kickouts, and fans. It describes the basic functions of these components in the CFB boiler system.
This document provides a summary of the key components of a circulating fluidized bed (CFB) boiler, including: the wind box and grid nozzle for distributing air, bottom ash drain, high pressure blowers, cyclone separators, evaporative/superheat walls, fuel and limestone/sand feeding systems, refractory lining, solid recycle loop seals, wall tubes, kickouts, and fans. It describes the basic functions of these components in the CFB boiler system.
Original Description:
Original Title
Components of Circulating Fluidized Bed Boilers.pptx
This document provides a summary of the key components of a circulating fluidized bed (CFB) boiler, including: the wind box and grid nozzle for distributing air, bottom ash drain, high pressure blowers, cyclone separators, evaporative/superheat walls, fuel and limestone/sand feeding systems, refractory lining, solid recycle loop seals, wall tubes, kickouts, and fans. It describes the basic functions of these components in the CFB boiler system.
This document provides a summary of the key components of a circulating fluidized bed (CFB) boiler, including: the wind box and grid nozzle for distributing air, bottom ash drain, high pressure blowers, cyclone separators, evaporative/superheat walls, fuel and limestone/sand feeding systems, refractory lining, solid recycle loop seals, wall tubes, kickouts, and fans. It describes the basic functions of these components in the CFB boiler system.
Download as PPTX, PDF, TXT or read online from Scribd
Download as pptx, pdf, or txt
You are on page 1of 20
CFB Boiler Simple Schematic Diagram
Components of CFB Boilers
Wind box and Grid Nozzle Bottom ash drain HP blower Cyclone Separator Evaporative or Superheat wing walls Fuel feeding system Refractory Solid Recycle System Wall tubes Kickout Limestone and Sand System Wind box and Grid nozzle Primary air is fed into wind box. Air is equally distributed on furnace cross section by passing through the grid nozzle. This will help mixing of air and fuel for complete combustion Bottom Ash Drain ( Slag coolers ) Coarse size of ash that is not take away from furnace by fluidizing air will be drain at bottom ash drain port locating on grid nozzle floor by gravity. bottom ash will be cooled and conveyed to silo by cooling conveyor. HP Blowers ( High Pressure Fluidizing Fans ) Supply high pressure air to fluidize bed material in loop seal so that it can overflow to furnace. Cyclone Separators Located after furnace exit and before convective part. Use to provide circulation by trapping coarse particle back to the furnace Fluidized boiler without this would be BFB not CFB Evaporative or Superheat Wing Walls Located on upper zone of furnace it can be both of evaporative or SH panel lower portion covered by erosion resistant materials Coal Feeding System ( Coal Feeders ) solid fuel is fed into the lower zone of furnace through the screw conveyor cooling with combustion air. Number of feeding port depend on the size of boiler Refractory refractory is used to protect the pressure part from serious erosion zone such as lower bed, cyclone separator Solid Recycle System ( Loop Seal ) Loop seal is located between dip leg of separator and furnace. Its design physical is similar to furnace which have air box and nozzle to distribute air. Distributed air from HP blower initiate fluidization. Solid behave like a fluid then over flow back to the furnace. Wall Tubes Located along the wall of the furnace. Contains saturated water from the bottom part of the steam drum and absorbs the heat from the combustion process. Kickout kick out is referred to interface zone between the end of lower zone refractory and water tube. It is design to protect the erosion by by-passing the interface from falling down bed materials Limestone and Sand System Sand is normally fed by gravitation from silo in order to maintain bed pressure. Its flow control by speed of rotary screw. lime stone is pneumatically feed or gravitational feed into the furnace slightly above fuel feed port. the objective is to reduce SOx emission Some other common parts of Boilers Primary Air Fan Secondary Air Fan Induced Draft Fan Heat Recovery Area Primary Air Fan Gives the furnace the air required for fluidization process and supports the secondary air fan for required air during combustion process. Secondary Air Fan Commonly similar to primary air fan in structure but is different in actual use. It primarily gives the furnace the air required for combustion process. Induced Draft Fan Gives the furnace a below atmospheric pressure for safer operation and directs the flue gases to the smoke stack. Heat Recovery Area An additional area of the boiler which increases the heat transfer efficiency by utilizing the flue gases being directed by the IDF.