Heating Efficiency of Twin Torch Plasma Arc

The twin torch plasma arc has a higher temperature arc column. For that reason, it can generate high temperature and treat non-conducting material, even though it is a non-transfer type. Therefore, the twin torch plasma arc is a more effective device for treatment of hazardous waste. However, the arc mode is not easy to control in the twin torch plasma arc. In this paper, a twin torch plasma arc with a rated current of 40 to 100 A is described such as arc mode, voltage as function of current and length, heating efficiency, and running cost for hazardous waste. The high temperature region of the twin torch plasma arc is larger than that of a conventional single plasma torch. The plasma arc length can be changed as a function of the plasma gas flow rate. The arc voltage is also variable as a function of the current and plasma gas flow rate. The temperature of twin torch plasma was measured to be about 10000 K near the cathode and anode, and 8900 K at the center point between the electrodes at 100 A. The neutral bar received heat power of the amount of 280-500 W, and the fraction of the total power transferred to the neutral bar is 12-18%.