Abstract: A method and apparatus for freezing a liquid droplet includes dispensing, by a liquid dispenser, a droplet of liquid into a fluid chamber containing a freezing liquid. The droplet of liquid is allowed to dwell in the freezing liquid for at least a predetermined dwell time so that the droplet of liquid freezes to a frozen droplet. The method and apparatus further includes injecting, by a gas injector, a stream of gas transversely to a surface of the freezing liquid at about where the frozen droplet is located along the surface of the freezing liquid contained in the fluid chamber so that the frozen droplet sinks in the freezing liquid.

Abstract: A method and a system for recovering aroma compounds from a coffee extract is provided. The coffee extract and a steam flow is provided to a two-fluid nozzle, to generate a spray of coffee extract in steam, which spray is separated to provide an aroma rich gas and stripped coffee extract.

Abstract: A freeze concentration method separates the nucleation and the growth processes at least to the extent necessary to enable nucleation and crystal growth to occur at different temperatures. Nucleation, however, is triggered by a sonicator, i.e., ultrasonic radiation. This provides excellent control of the process since the variables of the input sonic energy are adjusted easily. Most importantly, the use of ultrasound permits nucleation at low supercooling. The consequences of this are: an inexpensive plain--as opposed to the more complex and expensive scraped-surface--heat exchanger can be used since the coolant temperature is only slightly lower than that of the solution, preventing ice scaling in the heat exchanger; the higher coolant temperature leads to savings also in the operation costs. In addition ultrasonic nucleators are easily scaled-up to treating the large-volume effluents from industrial plants. The only way to scale-up scraped-surface nucleators is by using multiple nucleators in parallel.

Abstract: Coffee aroma gases are conveyed to a cryogenic collector in which liquid nitrogen is sprayed directly into the aroma gas stream to rapidly condense the aroma gas and form finely divided particles of coffee aroma frost suspended in a stream of nitrogen gas, while minimizing contact of the cooled gas with the walls of the collector. The suspension of aroma frost particles in gaseous nitrogen is passed through a tubular porous filter to remove the aroma frost particles which collect on the outer surface of the tubular filter, with the nitrogen gas passing through the porous filter and being exhausted from the collector. The porous filter is periodically back pulsed to dislodge aroma frost particles collected on the outer surface of the tubular filter, with the particles being recovered for incorporation in soluble coffee products.

Abstract: A method of producing microfine frozen particles from water, liquid drugs, juices, etc. comprises the steps of atomizing a mixture of a liquid with a gas and directing the mixture toward a body of a refrigerant liquid whose surface is stirred by application of kinetic energy to form ripples. The refrigerant liquid being liquid nitrogen, liquid air, a cooled organic solvent or the like, so that the atomized liquid undergoes heat exchange with the refrigerant liquid to form fine frozen particles. An apparatus for practicing the method, comprises a vessel for containing the refrigerant liquid, apparatus for forming ripples at the surface of the refrigerant liquid by injecting a gas, or by applying vibrations to the vessel or the refrigerant liquid, an atomizer functioning as a mixer and atomizer for a liquid and a gas, and an apparatus for collecting the microfine frozen particles from the refrigerant liquid.

Abstract: In a multistage countercurrent crystallization apparatus for multistage crystallization by adiabatic recrystallization and extractive washing comprising a vertical column containing a feed line, a waste material discharge, a purified product discharge, a crystallization zone or chamber at one end and a melter or dissolver at the other end, said vertical column containing a crystallizing liquid, a number of perforated plates subdividing said column into multistages, substantially spherical bodies contacting said perforated plates of a size larger than said perforations and designed to cooperate with the perforations of said perforated plates while in motion with respect to said perforated plates, means for vibrating said perforated plates whereby said substantially spherical bodies vehemently vibrate against said perforated plates, the improvement consisting essentially of reciprocating means to move said crystallizing liquid slowly and periodically with respect to said perforated plates in said column where s

Abstract: Freezing and melting techniques are described for separating 1,3-butadiene from a mixture of four-carbon compounds by fractional freezing of the liquid mixture and by fractional melting thereof. It has been discovered that when a frozen four-carbon mixture (BB) containing about 36% 1,3-butadiene (BD) is initially frozen, the first frozen fraction of up to about 30% of the mixture is enriched about 80% over the feed sample while the filtrate is decreased in BD about 36%. A second fractional crystallization of the melt and of the filtrate shows continued enrichment and impoverishment as to BD content, respectively. It has also been discovered that when a solidly frozen BB mixture is slowly thawed and the melt is progressively removed, the melt becomes markedly enriched in BD. A continuous fractional crystallization process that uses these discoveries for producing BD at purities greater than 99% is described.

Abstract: A process for the operation of a counter current crystallization column is described in which perforated plates or screens are positioned at spaced intervals. Movable objects such as steel balls or plastic balls are inserted in the column on each of the plates or screens and set into vibration by some kind of distance effect such as vibration of the entire column. The vibrating objects promote the passage of the crystals through the plate in that they have a milling effect on the crystals and are drumming against the plates. When said effect is wanted at the under side of the plates, supporting screens are mounted just below the plates and provided with the movable objects.

Abstract: Process is provided for the creation of crystal aggregates in one part of a tank by heat transfer from a fluid disposed in another part of the tank and maintained by heating or by cooling at a different temperature than the part containing the crystal aggregates. Both of these parts are separated from each other by a flexible membrane which is pulsated by dynamic local pressure differentials caused by foaming or by fluidizing the heat transfer fluid.

Abstract: An inspissate of a solution having a solvent which can be crystallized out by cooling is passed into contact with an internally cooled surface through which a coolant is circulated. Relative vibration is established between the solution to be cooled and the surface with at least the vibration of the surface being interrupted periodically or aperiodically. The solution and the surface can be vibrated separately in alternating periods.

Abstract: Crystallizable liquid solutions (i.e. solutions with crystallizable solvents) are concentrated by passing them between two cooled surfaces in a direction transverse to the action of gravity, the crystals being removed from the liquid substantially continuously over the entire length of the path. The surfaces are vibrated to prevent accumulation of crystals.

Abstract: Selected chemical species in fluid media such as solutions, mixtures of liquids, and suspensions are crystallized by indirect cooling of the fluid media. Crystals are prevented from sticking to the heat exchange surface by pulsating the fluid with a component of pulsation parallel to the heat exchange surface. The crystals can then be separated from the residual fluid.

Abstract: A method of making finely particulate ammonium perchlorate which comprises establishing a two-phase liquid system in which the upper phase is a concentrated solution of ammonium perchlorate and the lower phase is a liquid which is immiscible with the upper phase solvent and a non-solvent for ammonium perchlorate. Precipitation of ammonium perchlorate from the solution into the non-solvent is effected by either cooling the solution or evaporating the solvent thereof while subjecting the system to ultra-sonic vibrations. Fine ammonium perchlorate particles collect in the non-solvent phase and are recovered therefrom.

Abstract: A process and system for separating a preferentially crystallizable component A from a feed, wherein a series of zones are used between which mother liquor can flow without passage of crystallized material. Liquid feed is introduced to a zone other than the end zone from which effluent rich in component A is withdrawn. During one stage gradating crystallization temperature pattern is established throughout the series ranging from relatively low to relatively high, causing component A to crystallize in each zone; and mother liquor is caused to flow toward the low temperature end, while a portion of previously withdrawn effluent rich in component A is returned to the higher temperature end and effluent lean in component A is removed from the lower temperature end.