L-1500 pulverized coal furnace

Purpose

The L-1500 combustor is capable of firing natural gas and/or pulverized coal at a rate of 5 million Btu/hr. The facility is designed to simulate low emission, pulverized coal-fired boilers with wet walls and is used to investigate full-scale commercial electric power generating unit design and operation. The L-1500 furnace was built for testing different technologies such as staging, reburning, selective non-catalytic reduction (SNCR), and burner development, focusing primarily on the reduction of NOx emissions and particulate emissions.

Physical Description

The L-1500 is a 3.4-ft by 3.4-ft by 40-ft pilot scale furnace. Pilot plant and ancillary equipment include:

• 5 MMBtu/hr dual-swirl coal-fired burner.
• Air preheat system to heat secondary and tertiary combustion air to 800°F.
• Solid feeding system for pulverized coal including: feeders, hoppers, and eductors.
• Opto 22 distributed control system.
• Continuous emissions monitoring equipment for real time measurement of O₂, CO₂, CO, NO_x, and THC emissions.
• 6500 CFM wet venturi scrubber for abatement of SO2 and particulate emissions
• 400 ton cooling tower and shell and tube heat exchanger for indirect cooling of flue gases.

The single 5 MMBtu/hr burner can also be removed and replaced with a multiburner system consisting of three 1.5 MMBtu/hr burners.

Recent Projects

• Low NO_x firing system for coal fired wet bottom boilers.
• Methods for reduction of NO_x emissions and unburned carbon in ash.
• Fate of iron pyrites and unburned carbon.
• Air toxic emissions measured as a function of coal type and ash recycle for optimum low NOx conditions.
• Selective use of oxygen for NO_x control.
• Optimization of multiburner arrays for NO_x control.