On-stream NMR measurements and control

Abstract

Four examples are described in which nuclear magnetic resonance (NMR) measurements provided quantitative analyses with an accuracy of 1% of the amount measured. In the first instance, the amplitude of the NMR absorption of hydrogen was combined with the weight and volume of the sample to give a moisture determination in starch. The second NMR instrument used no sample weight and the amount of moisture in a flowing stream of Milo maize was measured by means of only the amplitude of the NMR absorption of hydrogen. The third instrument used the second harmonic of the NMR absorption from hydrogen to measure the amount of moisture in a flowing process stream of starch or other hygroscopic material without weighing. The last example described how the amplitude and area of the aluminum and hydrogen NMR absorptions, respectively, can be combined to measure the per cent aluminum and per cent hydrogen in a flowing process stream, again without weighing.