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Show High Efficiency, L o w Emission Marine Vapor Control System Callidus Technologies Inc. Burner Design Callidus has specially developed a multi-stage burner system that injects the auxiliary fuel separately from the vapor. The burner features a refractory tile in an aerodynamically designed configuration to maintain flame stability and promote mixing at much higher local temperatures than can be achieved by merely dumping fuel in a mainly nitrogen or CO2 fume stream. Along with the tile design, great care is taken configuring the ports of the auxiliary fuel nozzles. As discussed earlier, the vapor discharge tip also serves as flashback protection only when kept cool, thus, care must be taken when designing the burner to assure the integrity of the flame arrestor function. Callidus has developed a unique "flame holder" design for the flame arrestor burner tip that accomplishes this as well as creating excellent flame stability when auxiliary fuel is not required. Regulatory agencies place significant emphasis on the effect of time and temperature. The authors' experience indicates this regulatory drive for mandatory time and temperature relations are misguided and often result in significant expense without adequate results. The extreme example of this error can be found in the CMA/EPA studies of open air burning Open flames were tested over a wide variety of heating values, not exit velocities and gas compositions. One of the authors served on the E P A Peer Review Committee and acted as the director of the combustion non-analytical testing (analytical testing was ruled out by Radian and Engineering Sciences) on the C M A tests. Data from these test indicated that if stability was achieved, the DRE's were above 9 9 % in open air non-temperature controlled flares and essentially zero residence time outside of the flame. This data has been previously reported in several publications.1-2 The EPA, faced with the difficulty of defining stability, chose to statistically analyze the data and develop rules for exit velocity and L H V . Other papers have shown these are not the governing variables.3 Regardless of the calculation method used to predict stability, it was clear that, during any of the testing when stability was obtained, high DRE's resulted. Data reported by Cegielski4 also indicates the importance of stability in burner design as well as the effects of the design of the combustion chamber in a temperature controlled device. With DRE's of 99.99% at temperatures of 1500°F for carbon terra chloride, clearly a mechanism other than time and temperature is in effect. The production of a high stability, initial combustion zone appears to have a dramatic effect on the total D R E of the system. The variation in state-by-state regulatory controls for marine vapor units has allowed a comparison between temperature controlled and non-temperature controlled units. The summary below shows the difference in DRE between temperature controlled and non-temperature controlled units is less significant than the effect of burner stability. 3 |