| abstract |
AN ANALYTICAL APPARATUS AND METHOD FOR MEASURING POLLUTANTA IN AMBIENT AIR AND SPECIFICALLY FOR MEASUREMENT OF METHANE, EHTYLENE, ACETYLENE, CO, CO2 AND TOTAL HYDROCARBONS IN AMBIENT AIR. THE APPARATUS EMPLOYS A HYDROGEN FLAME IONIZATION DETECTOR AND THE GASES EMPLOYED IN THE ANALYSIS INSTRUMENT ARE ONLY THOSE GASES REQUIRED FOR COMUBSTION IN THE FLAME DETECTOR. AIR IS EMPLOYED AS THE CARRIER GAS IN A TOTAL HYDROCARBON ANALYSIS LINE TO THE DETECTOR. THE CARRIER AIR STREAM IS PASSED THROUGH AN OXIDIZER CATALYST TO COMPLETELY OXIDIZE THE HYDROCARBONS IN THE CARRIER AIR TO PROVIDE A TRUE "ZERO-HYDROCARBON" REFERENCE LEVEL IN THE IONIZATION DETECTOR AGAINST WHICH THE TOTAL HYDROCARBON CONTENT OF THE AMBIENT SAMPLE IS COMPARED. HYDROGEN IS EMPLOYED AS THE CARRIER GAS IN A GAS CHROMATOGRAPH ANALYZER FOR SEPARATING THE HYDROCARBONS AND CARBON MONOXIDE IN AN AIR SAMPLE. THE HYDROGEN CARRIER GAS SIMULTANEOUSLY PROVIDES THE HYDROGEN REQUIREMENTS OF A METHANATOR IN THE CHROMATOGRAPH LINE, WHICH CONVERTS CARBON MONOXIDE AND CARBON DIOXIDE INTO METHANE SO THAT A RELATIVE MEASUREMENT MAY BE MADE IN THE IONIZATION DETECTOR FOR THESE CONSTIUENTS, AS WELL AS THE HYDROGEN GAS REQUIREMENTS OF THE DETECTOR. D R A W I N G |