Abstract: A method and system for treating coal with hydrogen fluoride to remove fly ash and thereafter regenerating substantially all of the hydrogen fluoride used during the process (thereby significantly reducing the amount of HF on site). An exemplary method includes the steps of charging at least one reaction vessel with coal containing fly ash; feeding hydrogen fluoride into the reaction vessel to form a first reaction mixture of soluble reaction products, insoluble fluoride compounds and initially clean coal; separating out the first soluble and insoluble reaction products; feeding nitric acid into the same reaction vessel to react with any remaining fly ash components and separating out those second reaction products; and regenerating substantially all of the hydrogen fluoride used in the first fluoride reaction.

Abstract: A method for analyzing a system for safety to personnel or other systems is disclosed comprising: identifying at least one operating parameter of a first subcomponent of said product; identifying an inherent hazard of said first subcomponents based on an analysis of the at least one operating parameter; identifying features of the structure or operation of the subcomponent corresponding to the inherent hazard; identifying modifications or controls for the identified features which would mitigate the inherent hazard; prioritizing the identified features with respect to the effect that each of said features has on safety of the product; and determining whether an unsafe condition could result from the inherent hazard.

Abstract: A method for analyzing a system for safety to personnel or other systems is disclosed comprising: identifying at least one operating parameter of a first subcomponent of said product; identifying an inherent hazard of said first subcomponents based on an analysis of the at least one operating parameter; identifying features of the structure or operation of the subcomponent corresponding to the inherent hazard; identifying modifications or controls for the identified features which would mitigate the inherent hazard; prioritizing the identified features with respect to the effect that each of said features has on safety of the product; and determining whether an unsafe condition could result from the inherent hazard.

Abstract: A method for analyzing a system for safety to personnel or other systems is disclosed comprising: identifying at least one operating parameter of a first subcomponent of said product; identifying an inherent hazard of said first subcomponents based on an analysis of the at least one operating parameter; identifying features of the structure or operation of the subcomponent corresponding to the inherent hazard; identifying modifications or controls for the identified features which would mitigate the inherent hazard; prioritizing the identified features with respect to the effect that each of said features has on safety of the product; and determining whether an unsafe condition could result from the inherent hazard.

Abstract: A method for analyzing a system for safety to personnel or other systems is disclosed comprising: identifying at least one operating parameter of a first subcomponent of said product; identifying an inherent hazard of said first subcomponents based on an analysis of the at least one operating parameter; identifying features of the structure or operation of the subcomponent corresponding to the inherent hazard; identifying modifications or controls for the identified features which would mitigate the inherent hazard; prioritizing the identified features with respect to the effect that each of said features has on safety of the product; and determining whether an unsafe condition could result from the inherent hazard.