Sootblowing system with identification of model parameters

A device for identifying a parameter (a.sub.i) of a model for a rate of loss of boiler efficiency due to a sootblowing operation in one of a plurality of heat traps in a boiler, comprising:

• means for measuring the time since a last sootblowing operation in the i.sup.th heat trap ended (.theta..sub.bi);
• means for measuring an overall boiler efficiency (E) at a beginning of a sootblowing operation for the i.sup.th heat trap;
• means for measuring a change in efficiency (.DELTA.E.sub.1) in the boiler due to the sootblowing operation in the i.sup.th heat trap;
• and
• means for calculating the parameter (a.sub.i) using the equation:
• for i=1, ##EQU7## where, N.sub.i =a coefficient for fouling rate in the model of the l.sup.th heat trap
• M=the number of heat traps in the boiler
• .theta..sub.ci =time for sootblowing in the i.sup.th heat trap
• a.sub.i =a model parameter for the i.sup.th heat trap, and
• T.sub.j =the time since sootblowing in the j.sup.th heat trap.

A method of optimizing a sootblowing operation in a boiler having a plurality of heat traps lying in series along a gas flow path by sootblowing only one heat trap at one time comprising;

• selecting a set time (.theta..sub.bi) between sootblowing operations of each heat trap;
• calculating an optimum time (.theta..sub.opt) between sootblowing operations of each heat trap based on scaling parameters and a cost factor for the sootblowing operation;
• obtaining a difference value between set and optimum time for each heat trap;
• comparing the difference value for each heat trap with a selected value which is indicative of the desirability for initiating a sootblowing operation for each heat trap;
• and
• initiating the sootblowing operation only in the heat trap having the lowest difference value between heat traps indicated as desirable for initiating a sootblowing operation.