Online evaluation of the boiler energy efficiency associated with the soot blowing in coal‐fired power plants

Abstract Soot blowing is a common practice in coal‐fired power plants to ensure high energy conversion rate. The period of the conventional soot blowing is usually fixed, without the consideration of the load change and feeding coal switching. For the purpose of the soot blowing optimization, an approach to quantitatively evaluate the performance of soot blowing operations is proposed. Different heat exchangers' thermal resistances are calculated based on dynamic mass and energy balance to monitor their ash fouling deposition, and then, the boiler energy efficiency is predicted, adopting the rolling extreme tree boosting algorithm, and finally, the efficiencies with and without soot blowing are computed separately. With the data collected from a 350 MW ultra‐supercritical unit, pseudo‐online simulations are performed. The results show that even if the energy efficiency of the unit has exceeded 94%, a full‐process soot blowing may further increase the efficiency in some extent. For those subcritical units, the benefits should be higher.