Inductively Coupled Plasma Torch for Plasma Gasification Analysis

Plasma is known as the fourth state of matter, consisting of charged particles: positive ions and negative electrons. Plasma is formed by generating an electric or magnetic field which is used to ionize the gas. Plasma temperatures of interest can range between 3,000^oC to 10,000^oC. With these high temperatures, plasma is used to convert waste to energy, which is a process known as plasma gasification. It is a thermochemical decomposition of organic material. There are several methods of creating plasma; however, the purpose of this project is to analyze the aspects of an inductively coupled plasma torch. A typical ICP torch is composed of a quartz tube that allows the flow of a sample gas through it, operating at low pressures. Although many studies have been made with gas flowing under low pressure conditions, this study is concerned with atmospheric pressure discharges as well as using borosilicate glass as a replacement for quartz. A spiral coil is wrapped around the quartz/borosilicate cylinder and is attached to a radio frequency generator which produces an oscillating current. The inductive coil creates an oscillating magnetic field which excites the ions and electrons creating high temperature plasma. The plasma may then be used for biomass gasification forming synthesis gas. Synthesis gas is composed mainly of hydrogen and carbon monoxide which can be used as a clean source of energy. However, the composition of the syngas will vary depending on the gas used as input to the quartz tube.