Abstract: A vertical multistage expansion evaporator comprising contiguous vertically arranged evaporator compartments, passages permitting communication between contiguous compartments and flow control apparatus positioned at each passage which is adjustable simultaneously by a single adjusting operation from outside the compartments. The contiguous compartments have a common ceiling and floor defining a passage therebetween. Each compartment further comprises a vertical separating wall extending partially the distance from the floor to the ceiling to divide the compartment into liquid and vapor sections so that liquid in the bottom of one compartment flows into the vapor section of the compartment next below.

Abstract: A method of heat exchange comprising flowing liquid heat-exchanging media upwardly as a stream containing fluidized particles onto some of which material is precipitated from the liquid thereby enlarging the particles, temporarily increasing the flow rate of the stream to fluidize the thus enlarged particles, expanding the stream to decrease the flow rate and permit settling out of a coarse fraction of particles and returning the stream to its original flow rate to readmit particles into the non-expanded stream.

Abstract: A method and apparatus for exchanging heat between a moving fluid and a moving secondary fluid comprising passing a plurality of streams of secondary fluid upward through the moving primary fluid.