OCR Text |
Show Carbon Monoxide The burner demonstrated operation to less than 1.0% excess oxygen with no measurable CO. Figure 17A shows the CO-to-particulate relationship on the mechanical and steam atomizers. The steam atomizer is capable of only trace CO to less than 0.5% excess oxygen. Excess Oxygen Our test supports other testing which indicates that excess oxygen has more than a casual relationship to emissions, efficiency, and maintenance, and should be considered carefully in every application. There is a practical amount of excess oxygen required to complete combustion. This "practical excess oxygen" may vary from application to application depending on fuel characteristics, furnace size and configuration, type of process, combustion air temperature and pressure, fuel pressure, and type of atomization, to name a few criteria. From a practical standpoint, to optimize all of the above parameters may prove difficult on some existing furnaces. However, most existing, and all new, furnaces should have no problem optimizing design criteria to achieve operation to the "practical excess oxygen" level. You will note that all data collection was done at excess oxygen levels below 3%. Figure 18 indicates the normal "practical excess oxygen" requirement 12-42 |