Physical transformations dehydration

Mineralogical phases formed at different temperatures for each coal sample are summarized in Table III. The major mineral phases detected by XRD in LTA samples are quartz, pyrite, bassanite, kaolinite and plagioclase. The processes responsible for subsequent mineral transformations include oxidation, vaporization, sulfur fixation, dehydration and solid-state Interactions. The temperatures at which specific transformations occur are assigned on the basis of previous experimental work by Mitchell and Gluskoter (4) and published chemical data in the Handbook of Chemistry and Physics ( ). In addition to mineral-mineral interactions it is believed that reactions between minerals and exchangeable cations occur (2) ... 

It must also be noted that multiple PAT analyzers can be used on a single unit operation to understand the process. For example, Aaltonen et used in-line Raman spectroscopy and in-line NIRS to monitor the dehydration of MT in a lab-scale fluid bed dryer. A PLS model was generated to quantify the solid-state transformation using Raman spectra while water removal was monitored using NIRS. This proved to be an effective combination because physical and chemical information were monitored and extracted by way of NIRS and Raman spectroscopy, respectively. Such combinations of process analyzers offer enhanced capabilities to improve process understanding and control. 

Insulating oil plays a vital part in many types of electrical equipment, not only as an insulant but also as a coolant in transformers and as an arc extinguishing medium in circuit breakers. In each case, efficient operation of the equipment depends upon the purity of the insulating oil, which in service can be contaminated by oxidation, condensation and the presence of solids, such as colloidal carbon, formed by arcing in circuit breakers. The electrical and physical properties of the oil may be seriously affected, resulting in reduced operating efficiency or even equipment failure. Frequent replacement of the oil wiU be too costly, and reconditioning by filtration and vacuum dehydration to remove all contaminants is the economic answer. 

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