Introduction

How They Work

A boiler is key equipment in a steam power plant (PLTU). It converts heat from fuel combustion into steam to drive the turbine. Two common boiler technologies are Circulating Fluidized Bed (CFB) Boiler and Pulverized Coal (PC) Boiler. Both have the same purpose, but they use different combustion methods. This difference affects coal size, furnace temperature, emissions, fuel flexibility, and operating system complexity.

CFB Boiler Figure 1. Simple process of CFB Boiler • Coal is mixed with bed material. • Air from below keeps the material suspended. • Combustion occurs throughout the bed area. • The cyclone returns unburned particles. In a CFB Boiler, coal burns inside circulating bed material, so the combustion process becomes more even.

Pulverized Coal Boiler Figure 2. Simple process of PC Boiler • Coal is ground into fine powder. • Pulverized coal is injected into the burner. • It burns like a large flame inside the furnace. In a PC Boiler, coal is changed into fine powder and burned through a burner to produce very high heat.

Key Differences

Parameter	CFB Boiler	PC Boiler
Combustion method	Fluidized bed	Burner flame
Coal size	Coarse	Very fine
Furnace temperature	Lower	Higher
NOx emissions	Lower	Higher
Fuel flexibility	High	Medium
System	More complex	Simpler

Advantages of CFB Boiler ✓ Can burn low-quality coal. ✓ Can be used for biomass co-firing. ✓ Lower emissions. ✓ Limestone can be added to reduce SO2.

Advantages of PC Boiler ✓ Suitable for large power plant capacity. ✓ The most commonly used technology. ✓ Has many operational references. ✓ Suitable for large-scale steam power plants.

Conclusion

Both CFB and PC Boiler have their own advantages. CFB Boiler offers higher fuel flexibility and lower emissions, while PC Boiler is strong in large capacity and has become a widely used technology in steam power plants around the world. Boiler technology selection should match fuel quality, capacity needs, emission targets, and plant operating characteristics.