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Show 2. RSB TEST-SITE INSTALLATION Installation of a 3-segment, 30 inch (762 m m ) diameter R S B occurred in a 50,000 lb/hr (18 MW,h) Struther's steamer at a Chevron field site, near Bakersfield, CA, USA. Figure 2 shows a schematic of the burner, including the three full segments of active pad, and the cone end-cap. The cone end serves to reduce the insulated area compared to a blocked end-cap, and it avoids the flow distribution problems encountered with a flat active end. The 7.37 inch (187.2 m m ) gap between active segments results from fuel staging tests, not reported here. The Struther's oil field steamer consists of a 9 ft (2.7 m) diameter, 37 ft (11.3 m) long radiant section lined by 3 inch (76 m m ) diameter tubes, their centers placed 6 inches (152 m m ) apart. A convective section follows as the flue products turn upward toward the exhaust stack. Under normal operation, the steamers are also used to combust hydrogen sulfide, and the flue products are passed through a scrubber to remove the sulfur dioxide. During testing no hydrogen sulfide is present and the flue products are exhausted to atmosphere. A schematic of the burner installed in the Struther's steamer is shown in Figure 2. The fuel injection into the premix occurs downstream of the blower in an arrangement designed for this site for tests in 1995. Those tests only required a 30 hp (22 kW) blower (the commercial burners in these steamers have 50 hp (37 kW) blowers) and the combination of F G R with the 30 hp (22 k W ) blower gives a maximum burner firing rate near 33 MMBtu/hr (9.7 MW,h). The fan-limited system does not affect the final results of the demonstration. A 12 inch (305 mm) FGR line connected the boiler exhaust to the fan inlet. A butterfly valve was used to control the percentage FGR. Typical exhaust temperatures were 330 °F (165 °C) and typical F G R temperatures in the butterfly valve were 260 °F (127 °C). The loss in heat energy along the F G R piping will adversely affect the system efficiency. However, the loss in temperature does not change the stability of the burner and is not viewed to affect the test results. 3 |