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Show RADIANT SECTION RADIANT COIL PYROCORE BURNERS CONVECTIVE SECTION AFRC90-PAPER #713 Figure 8: Cut-Away Illustration of Radiant Cell Cabin Heater with Pyrocore Model PD Burners. Currently, Alzeta and KTI have supplied burners and heaters for two of these 80 MW plants. Each plant uses four 200 million Btu/hr HTF heaters packaged in a modular fashion to supplement the available solar heat. Figure 9 shows two of the heaters from the SEGS VIII plant. In addition to the high-efficiency, lowNOx performance available with the Pyrocore RCCH, these heaters have also demonstrated significant improvements in the responsiveness of the system to changing load demands. Whereas the old boilers used to take as long as four hours to come up to load, the HTF heaters can be brought into service in as little as twenty minutes. Figure 9. Two 200 Million Btu/hr HTF Heaters Using Pyrocore Porous Radiant Burners (Courtesy of KTI Corp. and Luz Construction, Inc.) Originally specified to be supplied as conventional heaters with 10w-NOx burners and flue gas recirculation, the Luz application 9 provides a unique opportunity to compare the design characteristics and process benefits of the Pyrocore based RCCH. Table 3, below, identifies the additional benefits achievable using the RCCH. Cost-effective NOx control is an important feature of the RCCH. The RCCH achieves impressive performance on a very competitive basis. Table 4, below, compares the capital costs of several alternative approaches to designing heaters with varying levels of NOx emissions and thermal efficiency. Except where extremely low levels of NOx emissions are mandated and Selective Catalytic Reduction (SCR) is required, the Pyrocore RCCH offers clear benefits over conventional design heaters using staged-fuel 10w-NOx burners (LNB). IMMERSION TUBE BURNER SYSTEMS Pyrocore Model PC packaged burners are used in a variety of retrofit applications of immersion tube heating systems. Storage tank and inline heating of bulk asphalt, moisture removal in glycol reboilers, and heat transfer fluid heaters and vaporizers are among the applications. Figure 10 illustrates the operation of a typical immersion tube burner. The burner heats the fluid across the frring tube wall by a combination of radiant and convective heat transfer. Typically installed as single burners in one or more firing tubes which are immersed in a tank or within a concentric pipe, these burners can operate on either natural gas, |