OCR Text |
Show operating on a 220 V supply, regulate the power supply to the electrical heaters. 2.3.2 Natural gas burner A domestic gas dryer burner (Sears part # 279273, type I-natural gas) with a rating of 25,000 Btu/hr is being used. The burner is housed inside the capacitance tank (Fig. 2). As the air flow inside the capacitance tank increases, the tank pressure increases. Hence a high pressure natural gas line (13 psi) with a pressure regulator is used so as to avoid the decrease in gas flow rate. The gas heater is used to accelerate the pre-heating. Further, it can be used to maintain the bed temperature when the quality of manure fired is of poor grade. 2.4 Diagnostic System Temperatures are measured with sheathed CrAl thermocouples (0mega-TJ36-CAIN-18U-12). Fig. 4 shows the thermocouple locations. Thermocouples 3, 4, and 5 measure temperatures inside the reactor, while thermocouples 1 and 2 measure the temperatures at the outer reactor wall ('skin' temperatures). The volumetric air flow rate is measured with rotameters installed in the air flow lines. The auger feeder has been calibrated with fuel in the feed hopper. Also, a check is kept on the fuel feed rate all the time during experiments by weighing each batch of fuel and checking the time taken for the feeding. Exhaust gas samples are taken out at the inlet and outlet of the water quench system by syringes for analysis by a Hewlett-Packard gas chromatograph. Chromatographic data gives the dry volume percentages of each component of gas in the exhaust. This is then used to 2.4.10 |