Inductively Coupled Plasma Spectrometer for On-Line, Real-Time Process Gas Analysis

摘要

On-line, real-time analysis of process gas streams, such as gasification and combustion processes, is becoming increasingly important. This dissertation describes an inductively coupled plasma spectrometer capable of analyzing for trace metals in particulate laden process gases that are injected directly into the ICP torch at high temperatures (500/degree/C) and at high sample flow rates necessary to maintain large particulate (10 to 20 micron) entrainment between the process sampling point and the plasma. The system uses a mixed gas argon-helium plasma, and use of the argon-helium plasma as opposed to a nitrogen, oxygen, or air plasma is defended. Characteristics of argon-helium and helium plasmas operated at very high rf forward energy levels are discussed and compared to the characteristics of an argon plasma operated under normal ICP conditions. Also presented are results of actual on-line testing of the ISP, some detection limits determined for elements in process gas types of streams, and the best emission lines to use for elements in process gas streams. 21 figs., 15 tabs. (ERA citation 14:026807)