Optimized Coal Pulverizer performance for best combustion efficiency

Pulverizer is the heart of the coal- fired power plants

Performance of the pulverizer is critical to:

• Combustion efficiency
• NO_x and CO reduction
• Unit availability

Many power operator have switched to the coal supply from the spot market, and turn to low grade coal. Low grade coal have higher ash content and moisture that could lead operation problems, i.e. high FEGT, boiler slagging and fouling issue. Furthermore, pulverizer performance will deteriorate over the time and lead to unplanned shutdown.

The milling process is complex, together with the varied coal quality and mill conditions, this makes air flow control not an easy task.

As regulations governing coal plant emissions have become increasingly strict and widespread, many users realized it’s importance to find the advanced solution for accurate airflow measurement and control for the pulverizer.

PULVERIZER/COAL MILL SAFE OPERATION & PERFORMANCE IS ESSENTIAL TO PC BOILER.

PULVERIZER AIR FLOW MEASUREMENT & CONTROL

The primary air transports pulverized coal from the mill to the burner to begin the combustion process by vaporizing moisture in the coal before combustion.

If too little air is supplied to the pulverizers it can cause:

• Pulverizer coal spillage
• Coal plugging in the piping from the pulverizers to the burners
• Low pulverizer outlet temperatures
• Incomplete combustion
• LOI (loss on ignition)/unburned carbon.

Similarly, too much airflow to the pulverizers causes problems with grinding of the coal (fineness), slagging and increased NOx emissions. Higher airflows also lead to erosion within the pulverizer and the coal piping, which increases maintenance costs.

Therefore, primary air should be accurately measured and controlled to provide safe and efficient operation.

In this application, TECG has developed the Smart Pulverizer Control, In this application, TECG has developed the Smart Pulverizer Measurement & Control which it target to provide a precise air flow measurement, AFR Control with reference to the coal feed input, coal flow condition. enable operation to map out the optinum operating point. which comprises of:

• Pulverizer Air Fuel Ratio (AFR) Optimizer
• Coal Fineness Optimizer
• Coal Flow Optimizer

The integration between the Pulverizer AFR Optimizer with the coal feed input and also coal flow condition, enable us to map out the optimum operating condition.