Combustion furnace system for analyzing elements in a sample

Abstract

The present invention discloses a system for analyzing elements contained in a sample in very slight amounts, such as C, S, O, N, H and the like in materials, such as steel and ceramics. An element analyzer can gasify the sample elements in an appropriate gas, such as oxygen gas in a high-frequency heating furnace or an electric resistant furnace. Resulting gas can be introduced into a mass spectrometer to permit a quantitative analysis of the sample elements. A metal sample can be levitated and heated and melted with induction current for producing the resultant gas for introduction to a mass spectrometer.

1 - 27 . (Canceled)  
     
     
         28 . A system for analyzing elements in a sample comprising: 
 a combustion member comprising one of a high-frequency heating furnace and an electric resistance furnace for receiving the sample;    a source of oxygen gas connected to the combustion member to supply oxygen gas to the combustion member as the sample is heated to gasify the elements in the sample;    a sample section means connected to the heating member by an exhaust conduit for sampling at a constant interval and at constant amounts;    a dust filter unit operatively connected to the exhaust conduit for removing dust;    an oxidizing device operatively connected to the exhaust conduit for oxidizing the gas output of the combustion member;    a dehumidifier for dehumidifying the gas output before the gasified elements are analyzed;    a mass spectrometer; and    a conduit connecting the sampling section to the mass spectrometer whereby the gasified elements are analyzed quantitatively by the mass spectrometer to determine at least an element of C, S, and N to an accuracy of 0.1 ppm.    
     
     
         29 . The system of  claim 28  further including a feedback circulating system for recirculating the gasified elements to the heating member until all of the elements in the sample are adequately gasified.  
     
     
         30 . A system for analyzing elements in a steel specimen, comprising: 
 a combustion member for receiving the steel specimen;    a source of oxygen gas connected to the combustion member to supply oxygen gas to the combustion member as the sample is heated to gasify the elements in the sample;    an exhaust channel from the combustion member for removing the gasified elements;    a dust filter unit, operatively connected to the exhaust channel, for removing any oxidized dust;    a dehumidifier unit, operatively connected to the exhaust channel, for removing water vapor;    an oxidizing device, operatively connected to the exhaust channel, for oxidizing any CO contained in the gasified elements;    a sampling section means, connected to the exhaust channel, for sampling at a constant interval and at constant amounts of gasified elements; and    a mass spectrometer connected to the sampling section whereby the gasified elements are analyzed quantitatively to determine the elements in the steel specimen.    
     
     
         31 . The system of  claim 30  wherein the mass spectrometer analyzes the gasified elements to an accuracy of 0.1 ppm.  
     
     
         32 . The system of  claim 30  further including means for providing an electric field to ionize the gasified elements prior to an introduction into the mass spectrometer including a heatable filament, an electron collecting electrode, an ion producing electrode, and an ion extracting electrode.  
     
     
         33 . The system of  claim 30  further including a feedback circulating system connected to the heating member and connected downstream of the dust filter unit and upstream of the mass spectrometer to provide a recirculation of the combustion gas containing the elements through the heating member before analysis by the mass spectrometer.  
     
     
         34 . The system of  claim 33  further including a suction pump operatively connected in the feedback circulating system to feed back the gasified elements until the steel sample is completely combusted.  
     
     
         35 . The system of  claim 34  further including a valve member for selectively connecting the exhaust channel to either the feedback circulating system or the mass spectrometer.  
     
     
         36 . The system of  claim 35  wherein the combustion member is selected from one of a high-frequency heating furnace and an electric resistance furnace.