NOx reduction project to meet Phase 1 RACT regulations

The Challenge

Owned by Northeast Utilities, Schiller Generating Station Unit 6 is a 50 MW, front-fired Foster Wheeler boiler, firing Colombian Bituminous Coal and No. 6 Fuel Oil. It required a reduction in NOx emissions to meet Phase I RACT regulations, down to less than 0.5 lb/mmBtu.

Baseline NOx emissions were 0.82 lb/mmBtu and RJM’s burner optimization capabilities were selected as the most cost-effective technology to meet Phase I RACT

RJM Solution

RJM installed coal flow orifice plates on the unit to balance the primary air and coal flow. These orifice plates were selected based on utilizing a dirty air pitot tube and RotorProbe. Secondary airflow was balanced utilizing RJM’s ADA technology. Secondary air shrouds were installed over the outside of the air register for balancing the airflow to the six burners. The burner center to center distance is only 5.5’ similar to a cell burner. Burner optimization included the addition of circumferentially and radially staged flame stabilizers and coal spreaders.

Results

NOx emissions were reduced by 50% to 0.40 lb/mmBtu at full load conditions.