Air pre-heaters play an integral part in the efficient operation of power plants. As the conditions in the plant change, for example by changes in fuels or operating cycles, demands on the air pre-heaters also change. When this happens, L&T Howden’s experienced engineers and site specialists can provide complete advisory service.

The wide range of benefits of retrofits are:

• Reduces the power demands of the draught fan, and thus raises the saleable power output.
• If the operating conditions have changed, replacement elements can improve overall performance significantly.
• Helps eliminate the temperature dilution effect of air leakage, and so helps reduce corrosion downstream of the air pre-heater.
• By reducing leakage it makes more air available at the coal mills, ensuring an adequate supply of pulverized fuel to the burners – especially when the coal is wet – and compensating for shortfalls in output.
• Reduced leakage also lessens the flow through the forced draught and induced draught fans, and thus eliminates the output shortfall that would be caused by overloading the fans.
• A routine cleaning of the elements with highly efficient soot blowers will ensure a steady heat transfer and minimize pressure drop in the plant system.
• If operating condition has changed then replacement elements can improve overall performance significantly.