page 327 |
Previous | 1 of 5 | Next |
|
|
Loading content ...
Radiometric Techniques for Tracing and Identifying Industrial Wastes FRED L. SMITH and C. J. LEWIS Directors of Research Colorado School of Mines Research Foundation, Inc. Golden, Colorado This paper is concerned with radiometric techniques for analyzing, controlling, and identifying industrial wastes. The coal and metal mining industries have long been aware of air and stream pollution, and have been forced to solve problems such as mine drainage, tailings disposal, off-gas effects from smelting operations, and many other such things. The further processing of the ores and concentrates into various metals and nonmetals and into chemical compounds of one kind or another gives the mineral industries an additional awareness of and interest in the safe, expeditious, and economical handling of industrial wastes. Radiochemical methods have proved fruitful in many geological, metallurgical, and chemical situations and, since industrial waste problems are in these disciplines, radiochemical methods should be equally useful here. Most of the things to be discussed are being applied in the mining and chemical processing industries and are certainly applicable to waste problems. Some of the ideas will have to be evaluated for the particular problem at hand and one or two of the ideas are far out in the blue and may never be practical. Because radiochemical methods depend upon the use of radioactive isotopes, it may be worthwhile to discuss isotopes briefly. Radioisotopes are simply unstable atoms that do not differ chemically from the stable atoms of the same element but do have a nuclear structure that cannot exist indefinitely in nature. Because the chemical properties of atoms depend on the outer shell of electrons, the radioactive atoms act chemically just as if they were ordinary nonradioactive atoms. The unstable structure eventually breaks down and in doing so emits radiation that enables one to detect the presence of the unstable atoms. The radiation that is emitted may be the heavy, intensely ionizing alpha particles that can be stopped by a very thin sheet of foil; it may be the light beta particles -- either positively or negatively charged electrons that can penetrate or be reflected from thin materials; but in most cases it will be penetrating gamma photons. Of course, mixtures of these radiations may occur. So far, some 1, 300 isotopes have been identified in nature or produced by man. Of this number, 279 are stable and the rest are radioactive. This large number of existing isotopes gives a broad basis for great versatility in industrial applications. The isotopes we are most concerned with are produced by fission of uranium, neutron capture, or transmutation. When a uranium or thorium atom intercepts a neutron -- that is, an uncharged particle of unit atomic mass --it may split up in any of over 30 different ways. Numerous isotopes are formed directly in the fission process and begin to decay into other radio- - 327 -
Object Description
Purdue Identification Number | ETRIWC196130 |
Title | Radiometric techniques for tracing and identifying industrial wastes |
Author |
Smith, Fred L. Lewis, C. J. |
Date of Original | 1961 |
Conference Title | Proceedings of the sixteenth Industrial Waste Conference |
Conference Front Matter (copy and paste) | http://earchives.lib.purdue.edu/cdm4/document.php?CISOROOT=/engext&CISOPTR=7917&REC=15 |
Extent of Original | p. 327-331 |
Collection Title | Engineering Technical Reports Collection, Purdue University |
Repository | Purdue University Libraries |
Rights Statement | Digital object copyright Purdue University. All rights reserved. |
Language | eng |
Type (DCMI) | text |
Format | JP2 |
Date Digitized | 2008-09-22 |
Capture Device | Fujitsu fi-5650C |
Capture Details | ScandAll 21 |
Resolution | 300 ppi |
Color Depth | 8 bit |
Description
Title | page 327 |
Collection Title | Engineering Technical Reports Collection, Purdue University |
Repository | Purdue University Libraries |
Rights Statement | Digital object copyright Purdue University. All rights reserved. |
Language | eng |
Type (DCMI) | text |
Format | JP2 |
Capture Device | Fujitsu fi-5650C |
Capture Details | ScandAll 21 |
Transcript | Radiometric Techniques for Tracing and Identifying Industrial Wastes FRED L. SMITH and C. J. LEWIS Directors of Research Colorado School of Mines Research Foundation, Inc. Golden, Colorado This paper is concerned with radiometric techniques for analyzing, controlling, and identifying industrial wastes. The coal and metal mining industries have long been aware of air and stream pollution, and have been forced to solve problems such as mine drainage, tailings disposal, off-gas effects from smelting operations, and many other such things. The further processing of the ores and concentrates into various metals and nonmetals and into chemical compounds of one kind or another gives the mineral industries an additional awareness of and interest in the safe, expeditious, and economical handling of industrial wastes. Radiochemical methods have proved fruitful in many geological, metallurgical, and chemical situations and, since industrial waste problems are in these disciplines, radiochemical methods should be equally useful here. Most of the things to be discussed are being applied in the mining and chemical processing industries and are certainly applicable to waste problems. Some of the ideas will have to be evaluated for the particular problem at hand and one or two of the ideas are far out in the blue and may never be practical. Because radiochemical methods depend upon the use of radioactive isotopes, it may be worthwhile to discuss isotopes briefly. Radioisotopes are simply unstable atoms that do not differ chemically from the stable atoms of the same element but do have a nuclear structure that cannot exist indefinitely in nature. Because the chemical properties of atoms depend on the outer shell of electrons, the radioactive atoms act chemically just as if they were ordinary nonradioactive atoms. The unstable structure eventually breaks down and in doing so emits radiation that enables one to detect the presence of the unstable atoms. The radiation that is emitted may be the heavy, intensely ionizing alpha particles that can be stopped by a very thin sheet of foil; it may be the light beta particles -- either positively or negatively charged electrons that can penetrate or be reflected from thin materials; but in most cases it will be penetrating gamma photons. Of course, mixtures of these radiations may occur. So far, some 1, 300 isotopes have been identified in nature or produced by man. Of this number, 279 are stable and the rest are radioactive. This large number of existing isotopes gives a broad basis for great versatility in industrial applications. The isotopes we are most concerned with are produced by fission of uranium, neutron capture, or transmutation. When a uranium or thorium atom intercepts a neutron -- that is, an uncharged particle of unit atomic mass --it may split up in any of over 30 different ways. Numerous isotopes are formed directly in the fission process and begin to decay into other radio- - 327 - |
Resolution | 300 ppi |
Color Depth | 8 bit |
Tags
Comments
Post a Comment for page 327