ClearSign Combustion says its project operating at Shell/Exxon joint venture Aera Energy’s facility in Bakersfield, California has increased system efficiency by 3 percent to 4 percent while operating at 52 million Btu/hour, simultaneously slashing NOx emissions to below 5ppm — well below the San Joaquin Valley’s strict air quality regulations.
The unit uses ClearSign’s Duplex technology, operating in a once-through steam generator (OTSG) system used for enhanced oil recovery.
ClearSign says its technology also shows a 1 percent thermal efficiency improvement compared to a baseline case with a conventional low NOx burner without flue gas recirculation (FGR). OTSG systems typically operate with FGR to lower NOx emissions. FGR, however, penalizes thermal efficiency, increasing fuel and electricity costs.
ClearSign estimates use of Duplex versus systems operating with FGR will reduce annual operating expense between $90,000 and $100,000.
In February the company reported that the unit using ClearSign Duplex technology, was operating at 42.5 Million Btu/hr while meeting the San Joaquin Valley Air Pollution Control District’s Rule 4320, which requires NOx emissions of 5 PPM or less (corrected at 3 percent O2).