A new energy saving and safety control technology for coal-fired boiler

temperature independent control for direct-firing pulverizing system

was introduced.In this technology

the hot air bypass of pulverizer is designed to independently control the pulverizer's outlet temperature and pulverized-coal piping temperature

thus the pulverized-coal piping temperature can be controlled within range from 100℃to 120℃

which is higher than the pulverizer's outlet temperature(70 ℃).As a result

the cold air quantity entered into the pulverizer can be reduced

and the boiler's exhaust gas temperature can decrease by 6 ℃to 10 ℃.When high volatile bituminous coal is used

this temperature independent control technology obviously improves the anti-spontaneous combustion and anti-explosion quality in the pulverizer because of the lower pulverizer's outlet temperature.It increases the velocity and ensures the pulverized coal conveying security in pulverized-coal piping

especially at low boiler load.This technology can be used in direct-firing pulverizing system equipped with double-inlet and double-outlet steel-ball pulverizer or medium-speed pulverizer

and has great application prospects.