OCR Text |
Show • 7 candidate burner materials. Approximately 10 different materials were subjected to life tests and performance analyses prior to selecting the HT burner fiber. Following this initial selection process, subsequent Lifetime Facility tests were performed to optimize the burner formulation for steam-methane reformer operating conditions. Relative fiber loading, burner porosity, and the proportions of other pad materials were varied in developing this optimum formulation. Following the selection of the HT formulation, a larger scale burner performance and life test was conducted in the Alzeta PPH facility. The PPH simulates reformer tube wall temperatures and heat flux at a maximum burner fired duty of about 700 MBtu/hr. A S.S fe cylindrical burner was fabricated and installed in the PPH for testing. Burner performance data were collected as a function of total fired duty and excess combustion air over the range of operation anticipated for the reformer application. Radiant section efficiency is presented in Figure 1, and NOx emissions are presented in Figure 2. Included is these figures is one data point for a non-radiant premixed burner. Note that thermal efficiency of the non-radiant burner was similar to that of the radiant burner, but NOx emissions were considerably higher at the tested level of excess air. At the conclusion of these scoping tests, the burner was operated at approximately 80 percent of the design point for 4000 hours. Little change in burner performance or appearance occurred over this test period. Preliminary Field Demonstrations Following the successful 4000 hour PPH burner test, the HT burner formulation was scaled to 20 fe for a preliminary field demonstration at Evergreen Oil, a motor oil recycling plant in Newark, California. In this demonstration, the Pyrocore HT was one of 6 radiant burners installed in a fluid heater at the Evergreen facility. Nominal operating conditions for each burner are 2 MMBtu/hr fired duty, 2S0°F combustion air preheat, and a 400°F to SOO°F process temperature. The burner was installed in October 1993, and has been operating at a 70 to 80 percent utilization factor. The burner has accumulated 6000 hours of operation, and there are no plans to remove the burner from service at this time. |