Development and Calibration of Standards for PNAA Assay of Coal
The applicability of the Prompt Neutron Activation Analysis (PNAA) method to large (100kg) coal samples has been demonstrated in a laboratory system developed by SAI, Sunnyvale(1–3). The PNAA technique is based on irradiating the coal with neutrons and simultaneously detecting the characteristic prompt gamma radiation resulting from thermal neutron absorption in various elements in the sample. Detailed elemental analysis of the sample is obtained through careful analysis of the emitted gamma-ray spectrum. The accuracy of this method depends on the availability of a reliable set of coal standards. The elemental composition of this set should be well known and uncertainties of the order of ± 1% are desirable. The present available standards of coal are very small (1 g) and therefore not suitable for PNAA work. The aim of the present study was to develop and calibrate a new set of large coal standards which would be used in future PNAA field systems. This set has to cover a broad range of different types of coals, taking into account physical characteristics and elemental compositions. The present set of standards was calibrated against the sampling and analytical ASTM methods which were found to give reliable values.
KeywordsCoal Sample Neutron Source Carbon Capture Standard Calibration Curve Electric Power Research Institute
Unable to display preview. Download preview PDF.
- 1.T. Gozani, etal. “Prompt Neutron Analysis-Applications to Coal Analysis”, ANS Trans 26, 160, (6/77). See also EPRI Reports RP 983-1 Vol. 1 through Vol. 8a 1979.Google Scholar
- 2.T. Gozani, et al. “Coal Steam Composition Analysis for Process Control Using Prompt Neutron Activation Analysis”, ISA Symp. Instrumentation and Control for Fossil Demonstration Plants, June 1977.Google Scholar
- 3.T. Gozani, et al. “Advanced Techniques for Laboratory and On-Line Analysis of Coal”, ISA Symp. Instrumentation and Control for Fossil Demonstration Plants, August 1979.Google Scholar
- 4.J. McQuaid, T. Gozani and D. Brown, “High Countrate High Resolution Electronic System for Ge(Li) Detectors”. IEEE Trans. 19, Nuclear Science Symp. 1980.Google Scholar