Benefits and Experience with Coal and Air Flow Measurement and Automatic Control on Pulverized Coal Fired Boilers - Update 2003

摘要

Even the best burners is the world will not achieve optimal performance if fuel and air is not balanced. Controlling near field stoichiometries at the burners is being demonstrated as essential toward achieving ultra low emission performance. In an effort to provide continuous technology updates on the effects of air to fuel balance, this paper presents new results and benefits associated with using TR-Tech's Electric Charge Transfer (ECT) coal flow measurement technology. Since introduction, numerous new ECT coal flow measurement systems have been installed on wall, tangential and Riley turbo coal fired boilers. This system provides operators with continuous real time indication of coal flow distribution, conduit velocity and coal fineness, allowing better optimization of firing system performance. In conjunction with Foster Wheeler's air flow measurement and control, fully automated air to fuel flow control systems are in long term commercial operation. Four case studies are presented where ECT and air flow measurement was used as a combustion improvement tool. The results show emission and boiler performance improvements when air to fuel flow is actively balanced.