Factor analysis can reduce much analysis variables collected

meanwhile

it also retains the information contained in the original variable to a maximum degree.Taking the W flame boiler in a 350MW unit as the example

the factor analysis was applied to reduce the dimensionality of multiple indicators that can reflect economic and environmental performance of the boiler

then the combined score was calculated by weighting.According to the evaluation results

a comparison was carried out for different operation conditions with the same load.The results indicate that application of the combined score evaluation for boiler operation got access to the compromise of economic and environmental benefits.For instance

in the mill A

B and D combination mode

the boiler efficiency under 300MW unit load was about 0.2%to 0.5% higher than that under other operation conditions

and the NOx concentration was 8mg/Nm3(standard state)lower than the maximum value with the same unit load.