Abstract: A body of heat transfer fluid circulates in a first loop through an indirect screw-type thermal processor, a rundown tank, a pump, a heater and a fill tank, continuously heating the processor. With the pump operating, a first vertical distance between the fill tank bottom and the processor under the influence of gravity sets a minimum fluid pressure at the processor; a stem pipe opening in the fill tank at a second vertical distance above the processor sets a maximum pressure. With the pump inactive, the entire body of fluid passively drains to the rundown tank. Supplying the fluid may entail melting a salt, hydrating a salt, or both; such may be done in the rundown tank before circulation through the processor begins. A hydrated salt may be circulated, then heated and dehydrated, to gradually warm the processor. A dehydrated salt may be rehydrated and then stored; this may be done in the rundown tank after ceasing circulation through the processor.

Abstract: Serially connected heat exchange segments of a heat exchanger are stacked with ends of adjacent segments oriented oppositely. The segments have fixed pipes for heat exchange, pipe-riding shaftless auger flights for conveying feed material, and flanges for low-cost adjustment, removal and replacement of pipes and flights. Flights when arranged in arrays are arranged in pairs of counterrotating oppositely handed mutually cleaning flights. Rotary unions are unnecessary in this exchanger.

Abstract: A body of heat transfer fluid circulates in a first loop through an indirect screw-type thermal processor, a rundown tank, a pump, a heater and a fill tank, continuously heating the processor. With the pump operating, a first vertical distance between the fill tank bottom and the processor under the influence of gravity sets a minimum fluid pressure at the processor; a stem pipe opening in the fill tank at a second vertical distance above the processor sets a maximum pressure. With the pump inactive, the entire body of fluid passively drains to the rundown tank. Supplying the fluid may entail melting a salt, hydrating a salt, or both; such may be done in the rundown tank before circulation through the processor begins. A hydrated salt may be circulated, then heated and dehydrated, to gradually warm the processor. A dehydrated salt may be rehydrated and then stored; this may be done in the rundown tank after ceasing circulation through the processor.

Abstract: A body of heat transfer fluid circulates in a first loop through an indirect screw-type thermal processor, a rundown tank, a pump, a heater and a fill tank, continuously heating the processor. With the pump operating, a first vertical distance between the fill tank bottom and the processor under the influence of gravity sets a minimum fluid pressure at the processor; a stem pipe opening in the fill tank at a second vertical distance above the processor sets a maximum pressure. With the pump inactive, the entire body of fluid passively drains to the rundown tank. Supplying the fluid may entail melting a salt, hydrating a salt, or both; such may be done in the rundown tank before circulation through the processor begins. A hydrated salt may be circulated, then heated and dehydrated, to gradually warm the processor. A dehydrated salt may be rehydrated and then stored; this may be done in the rundown tank after ceasing circulation through the processor.

Abstract: A self-cleaning multiple helical auger conveyor for a processor has an array of pairs of opposite-handed, counterroatating helical augers with flights intermeshed such that the front of every flight is cleaned by the back of another flight and the back of every flight is cleaned by the front of another flight. Optionally, the flights are shafted and the periphery of every flight and the shaft of an adjacent flight mutually clean one another. Rectangular and polar arrays of such paired flights are described, along with relationships among flight thickness, clearance, pitch and number of flights. A flight having a coined surface and a cleaning tab projecting therefrom is described. Support, gearing and housing for various embodiments of the conveyor are described.