According to the actual situation and safety and environmental requirement of the boiler

a method for determining the scheme of in-deep mixedly burning inferior coal is proposed through applying mathematical model. Taking a 600 MW unit boiler as an example

the scheme of in-deep mixedly burning inferior coal at full load is made and the field verification experiment of mixedly burning is carried out. The results show that

the proposed scheme in this study can maximize the profit of the mixedly burning inferior coal with the precondition of safety and environmental operation of boiler. The maximum mixing ratio of inferior coal is 30% in the test unit at full load. Furthermore

with the increase of the mixing ratio of inferior coal

the efficiency of boiler decreases and the auxiliary power consumption rate increases. However

considering the coal cost

it can be calculated that the cost can be reduced by 0.008 yuan/(k W·h) at the maximum mixing ratio of inferior coal.