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 products
View More
-
SZL series coal-fired steam boilerLive Chat6-35 t/h1-2.5 MPa -
DZL series coal-fired steam boilerLive Chat2-10 t/h1-2.5 MPa -
DHL series coal-fired steam boilerLive Chat20-75 t/h1.25-5.4 MPa
By boiler medium
By boiler structure
-
Email us
-
WhatsApp: +86 18861589035
WeChat: +86 13506150756
Live Chat
Related news
View More
-
In industries such as chemicals, plastic packaging, new materials, and building materials, thermal energy supply is closely related not only to production continuity, but also to product quality and operating costs. As companies place higher requirements on process temperature control, fuel adaptability, and system stability, thermal oil boilers are becoming an important heat source in many industrial applications. Based on different fuel conditions and production needs, ZOZEN Boiler continues t...02 Jun 2026 -
Packaging connects production with consumption. A carton, a piece of corrugated board, or a roll of plastic film may look light and simple, but behind each of them is a stable, continuous, and process-matched thermal energy system. As demand continues to grow in food packaging, industrial packaging, e-commerce packaging, and plastic packaging, the packaging industry is placing more specific requirements on boiler equipment: stable steam supply, fuel adaptability, process temperature control, ope...26 May 2026 -
When an industrial boiler arrives on site, what first catches a customer’s attention is often not the specification sheet, but the overall appearance of the equipment in the plant environment. For boiler equipment, exterior design is not only about visual presentation; it also reflects the manufacturer’s approach to product details, on-site management, and brand image. ZOZEN Boiler has upgraded the exterior of its SZL series biomass boiler, presenting a more unified visual design and...19 May 2026
Latest cases
View More
