The efficiency of a modern boiler using coal and heat recovery equipment is about_____________?
A. 25 to 30%
B. 40 to 50%
C. 65 to 70%
D. 85 to 90%
The efficiency of a modern boiler using coal and heat recovery equipment is about_____________?
A. 25 to 30%
B. 40 to 50%
C. 65 to 70%
D. 85 to 90%