zozen boiler
Home Service FAQs FAQ of coal-fired boilers What are the functions of primary air and secondary air in a pulverized coal fired boiler?

What are the functions of primary air and secondary air in a pulverized coal fired boiler?

22 May 2020

(1)Primary air is used for transportation of fine coal particle from coal mill to boiler floor at different elevations as per requirement.

(2)Primary air is used for preheating of moisturized coal into the coal mill so that minimum energy is required for combustion of the same.

(3)As we all know that only 23% oxygen is available in the air by weight. For combustion of huge quantity of coal inside the boiler very high quantity of oxygen is required. This oxygen requirement will be completed by secondary air which is supplied by FORCED DRAFT fans through ducts.

(4)This secondary air is coming via air preheater hence its outlet temperature increases this will help in combustion and low heat input is required for combustion of coal.

Related FAQs View More
Related news View More
  • ZOZEN Boiler Supplies Gas-Fired Steam Boilers to Venezuelan Industrial Plants
    Over the past two years, ZOZEN Boiler has supplied gas-fired steam boilers and related services to industrial customers in Venezuela. The applications include beverage production and papermaking. This article presents two projects: a 3 t/h WNS gas-fired steam boiler supplied to a Venezuelan beverage manufacturer and a 15 t/h WNS gas-fired steam boiler supplied to a local paper mill. Steam Supply for Beverage ProductionSteam is used in beverage production for blending, sterilization, equipment ...
    18 Aug 2026
  • Steam Runs Through the Brewing Process: ZOZEN Boiler Supports the Baijiu Industry
    Baijiu production is a continuous process. From grain steaming and fermentation to distillation, sterilization, and fermented-grain residue handling, many stages require a stable steam supply. As baijiu producers expand their operations, boiler systems need to provide sufficient steam while also adapting to different fuel conditions, changing loads, and environmental management requirements. In recent years, ZOZEN Boiler has developed steam boiler and auxiliary system solutions for baijiu produ...
    11 Aug 2026
  • A 10 TPH Boiler Delivered in 40 Days: The “ZOZEN Speed” Behind Yanjing Beer’s Letter of Appreciation
    Recently, Wuxi Zozen Boilers Co., Ltd. received a letter of appreciation from Yanjing Beer (Guilin Lijiang) Co., Ltd. In the letter, the customer expressed appreciation for ZOZEN Boiler’s responsiveness, coordination, and delivery support throughout the project. The customer also noted that ZOZEN helped resolve issues related to scheme adjustments, equipment access, and the delivery schedule. Letter of appreciation from Yanjing Beer (Guilin Lijiang) Co., Ltd. The letter was related to ...
    04 Aug 2026

Find the Right Boiler For You

Name *

Email *

WhatsApp/WeChat

Products

Power/Capacity