“Valmet‘s experts have been able to provide us with a cost effective solution that has demonstrated concrete improvements in overall boiler control and have helped us to obtain considerable reduction in process variation,” says Scott Alley, Utilities General Superintendent, Rumford Mill, Catalyst Paper.
The application has been integrated into the mill’s existing automation system. It enables the mill to improve boiler steam output control and optimize limestone use, steam output variability and grid temperature variability. Additionally, it’s now possible to operate both boiler units in fully automatic control for varying compositions of coal and biofuel. The application also provides the tools to improve operational uniformity across shifts.
“Valmet DNA FBB Combustion Manager is a powerful tool to control combustion variables simultaneously,” says David Eapen, Performance Improvement Engineer, Automation, Valmet.
Valmet’s delivery included a complete Valmet DNA FBB Combustion Manager application, engineering, boiler base control logic enhancements, commissioning, tuning and training. Valmet also provided a Valmet DNA Fuel Power Compensator application that compensates for disturbances caused by fuel quality and amount variations by regulating fuel feeding respectively.
“The project to implement Valmet’s advanced boiler controls at the Rumford Mill was a big success. From initial control logic design, to hardware and software commissioning, to operator training, Valmet performed as promised,” says Steve Day, Process Control Engineer and Project Manager, Rumford Mill, Catalyst Paper.
Technical information about Valmet’s solution
Valmet DNA FBB Combustion Manager is an advanced control application for the optimized combustion of both bubbling and circulating fluidized bed boilers. The purpose of the application is to protect the combustion process against variations in production, fuel amount, fuel quality and combustion circumstances. As a result, DNA FBB Combustion Manager provides several environmental, operational and financial benefits, including a stabilized combustion process, increased boiler efficiency, a wider boiler operation range, minimized flue gas oxygen content as well as minimized NOx and CO emissions.
Valmet DNA Fuel Power Compensator is based on the estimation of fuel power input to the boiler. No additional sensors or transmitters are needed. The application calculates the fuel power online and compensates it by regulating the fuel flow accordingly. Valmet DNA Fuel Power Compensator is especially applicable for combusting multiple fuels with different fuel-specific heat values. A combustion process with changing solid fuel mixtures or a single fuel with varying dryness can also benefits from the application.