Dual Fuel Firing - The New Future for the Aging U.S. Based Coal-Fired Boilers

摘要

As the emissions regulations for power plants are becoming ever more restrictive and operating the equipment and cost for coal-firing power is increasing, the industry is turning to natural gas firing. This presents a concern for the existing U.S. power generation base of coal-fired boilers. Many owners are conducting investigative test firing of natural gas to determine the long-term feasibility of either conversion or dual fuel firing to meet the demands for electric power. Other utilities are having exhaustive feasibility studies performed to evaluate the impact of converting a boiler from solid or liquid fuel to natural gas. Recently, Riley Power Inc (RPI) in conjunction with a major Southeast utility conducted a week-long program to test the boiler's ability to fire full load natural gas in an existing RPI low NO_x coal-fired burner. The goal was to determine the ability of the equipment to meet steam load requirements and emissions requirements. The result of this investigation is that the unit can achieve the original steam flow capacity and meet the current emissions regulations. However, substantial control changes will be necessary to ensure the unit can operate automatically on load control. This paper will detail the findings of the testing, the future work that will need to be completed and the challenges to make dual fuel firing a working reality for an existing coal-fired boiler.