BMS/Fuel Regulatory and Combustion Controls
Many existing Boiler and Combustion Systems still rely on manual operator or basic relay-based systems with push button interfaces for safety control. With the continued industry push for safer more reliable systems the governing standards have changed. The prevalent code in Canada is CSA Standard B149.3. This code addresses the two systems (combustion control system with respect to air/fuel ratio and burner management system with respect to flame safety) present in fuel combustion equipment. The two control systems are separate and distinct, and, except for certain circumstances in single-burner boiler applications, must be maintained independently.
The burner management system is defined as "the control system dedicated to combustion safety and operator assistance in the starting and stopping of fuel preparation and burning equipment, and for preventing misuse of, and damage to, fuel preparation and burning equipment." Subsystems can include interlock systems, fuel trip systems, master fuel trip systems, flame monitoring and tripping systems, ignition subsystems, main burner subsystems, warm-up burner subsystems, bed temperature subsystems, and duct-burner systems.
The combustion control system is defined, in part, as "the control system that regulates the furnace fuel and air inputs to maintain the air/fuel ratio within the limits required for continuous combustion and stable flame throughout the operating range of the boiler in accordance with demand."
These systems can be integrated into the mill’s standard control system architecture which may be either DCS based or PLC/HMI based. They also require detailed engineering to provide for installation and wiring of the equipment and completion of required drawings in order to provide for a fully documented installation. In most jurisdictions regulatory approval is required to install any new gas burning appliance or equipment. This approval involves submission of all design documentation including system logic and wiring drawings, valve train drawings, operating manuals, training records, device information and specifications for review prior to start-up of the equipment.
KMH has successfully implemented BMS system projects following aggressive project and shut down schedules including new PLC/DCS installations, existing PLC system upgrades, and the complete commissioning of the PLC logic, DCS control configuration and graphic display interface and required cold trip tests prior to start-up and hot trip tests during final approval stages. KMH has experience with the following regulations
- CSA B149.3 Code for Field Approval of Fuel-Related Components on Appliances and Equipment
- NFPA 86 Standard for Ovens and Furnaces
- NFPA 85 Boiler and Combustion Systems Hazards Code