https://cementl.com/ In large coal-fired power plants, the boiler fuel system must deliver pulverized coal with consistent fineness and flow to maintain stable combustion. For units in the 1,300 MW range, roll wheel pulverizers are commonly applied due to their ability to handle high throughput, adjust to coal variations, and operate continuously under heavy thermal demand. A roll wheel pulverizer uses grinding rolls pressed against a rotating grinding ring to crush and grind raw coal, while primary air dries and transports the pulverized fuel to the furnace burners.
Website: https://cementl.com/
Email: [email protected]
Whatsapp: +86 15988878668
A single pulverizer in this category can process 75–100 tons of coal per hour, depending on coal quality and desired fineness. In a 1,300 MW boiler, a typical configuration might include 8 to 10 pulverizer units, each feeding a sector of the furnace burners. Raw coal with a size of up to 50 mm and moisture content between 6–12% is delivered by gravimetric feeders into the grinding zone. The rolls, mounted on spring or hydraulic loading mechanisms, exert grinding force on the coal bed formed on the rotating ring.
The grinding environment is maintained with primary air supplied from the boiler air preheater at temperatures around 250–320°C. This hot air both dries the coal and carries fine particles upward into the classifier. The classifier separates fine pulverized fuel (typically 70–75% passing through 200 mesh, or 75 μm) for combustion, while coarse particles return to the grinding zone. The outlet temperature of the pulverized coal-air mixture is controlled between 70–80°C to ensure safety and prevent condensation in the fuel lines.
Wear resistance is one of the most critical aspects of pulverizer operation. The grinding rolls and rings are exposed to continuous abrasion from mineral content in the coal. To improve reliability, Magotteaux wear parts are often used. These parts are engineered with high-chromium metallurgy and ceramic inserts, extending the service life of grinding components by 30–50% compared to standard materials. Longer wear life reduces maintenance outages and stabilizes mill performance by keeping grinding pressure consistent over time.
In operation, the roll wheel pulverizer must be carefully monitored. Key parameters include grinding pressure (usually 80,000–120,000 pounds per roll assembly), mill differential pressure (10–15 inches water column), and classifier vane position. Vibration levels provide early warning of roll imbalance or bearing wear. Mill reject handling is also important; pyrites and tramp iron are discharged through the reject system to avoid damage to rolls and ring segments.
Boiler performance depends heavily on pulverizer output. If coal fineness deteriorates, larger unburnt carbon particles reach the furnace, leading to higher loss on ignition (LOI) in fly ash and reduced boiler efficiency. Conversely, overly fine grinding increases power consumption and wear. Maintaining correct classifier settings and roll-to-ring clearance is therefore essential.
During plant startup, inerting systems with CO₂ or N₂ are often used before coal is fed, reducing the risk of mill explosions. Continuous CO monitoring in the mill outlet stream provides an additional safeguard. The pulverizer control system adjusts feeder rate, grinding pressure, and primary air flow according to boiler load demand.
For a 1,300 MW coal-fired boiler, the coordinated operation of multiple roll wheel pulverizers ensures uniform distribution of fuel across all burners, stabilizing furnace temperature and reducing NOx emissions. With Magotteaux wear parts, operators benefit from extended maintenance intervals, predictable wear patterns, and reduced downtime for roll and ring replacement. This allows the power plant to sustain base-load operation with high availability.
#vrm #verticalrollermill #cement #cementindustry #ballmill #ballmillfactory #ballmillparts #dryer #granulator #cooler #machinery #heavymachinery #mining #cement #crusher #ballmill #rotarykiln #agriculture #agricultureequipment #granulation #granular #rotarykiln #rotarydryer #kiln #fertilizer manufacturing machine #fertilizergranulator
#fertilizer #npk #verticalrollermill #clinkergrindingunit #cementequipment #ballmill #ballmillsupplier #cementplant #rotarykiln #rotarykilnparts #kiln #shaftkiln #mining #cement #crusher #rotarydryer #girthgear #casting #metalcasting #foundry #supportroller #ridingring #tyre #edgedrive #centraldrive #cementmachine #cement #cementcrushing #cementplant #cementballs #ballmillparts #ballmillfactory #cementgrindingplant #clinkergrinding #rotarykilnparts #grinding #grindingplant #grindingequipment #tongli #zhejiangtongli #tongliheavymachinery #Rollpress #Impactcrusher #Impactor #tonglicement #JawCrusher #angola #tanzania #namibia #ghana #kenya #zimbabwe #nigeria
Информация по комментариям в разработке