Abstract:
The present invention provides methods and systems for reducing moisture in mineral slurries, particularly mineral slurries containing minerals of small particle diameter, using a granular drying material. The invention also relates to novel mineral products and intermediates useful in connection with the process. The method and system reduced moisture by contacting the mineral slurry with the granular drying material. The granular drying material is selected to be readily separated from the dried minerals using a size separation technique such as a sieve screen. The granular drying material is the regenerated, preferably using a process involving heat exchange and cross-flow air. The granular drying material is preferably capable of regeneration and recycling in a continuous process with minimal attrition.
Abstract:
The present invention provides methods and systems for reducing moisture in mineral slurries, particularly mineral slurries containing minerals of small particle diameter, using a granular drying material. The invention also relates to novel mineral products and intermediates useful in connection with the process. The method and system reduced moisture by contacting the mineral slurry with the granular drying material. The granular drying material is selected to be readily separated from the dried minerals using a size separation technique such as a sieve screen. The granular drying material is the regenerated, preferably using a process involving heat exchange and cross-flow air. The granular drying material is preferably capable of regeneration and recycling in a continuous process with minimal attrition.
Abstract:
Solid carboniferous fuels contain varying quantities of moisture, mercury, chlorine, nitrogen, sulfur, heavy metals and other materials that attain vapor pressure at elevated temperatures. The cost effective removal of these degrading and sometimes hazardous materials is important to the further use of the fuel for combustion via chemical looping to prevent contamination of the oxygen carrier medium. The solid fuel is cut, shredded, ground or sieved to appropriate size, and heated in a chamber that can exclude oxygen and air thus preventing ignition. The unwanted materials are driven in the gaseous state and extracted for recycling or safe disposal. The solid fuel cleaned of pollutants exits the chamber and is cooled below ignition temperature prior to contact with oxygen. The solid fuel thus purified is more appropriate for combustion via chemical looping.