Power Plant Instrumentation and Control Handbook

5. Coal Mill Control—Mill Air Flow for TT Boiler

5.0. General

There are two main modulating control systems associated with mills. These are mill air flow control and mill temperature control. Mill temperature control is covered in Section 5.1 of this chapter. Mill air flow controls in opposed-fired and front-fired boilers based on Babcock designs are mainly based on PA DP controls and are well covered in Section 4 of this chapter. In this section only mill a controls for TT boilers (bowl mills) are discussed. Mill air flow controls for tube mills are covered in Section 4.4.3 of this chapter and also detailed out in Section 5.2 of this chapter. Apart from these there may be a few more controls associated with tube mills these are covered in Section ...