Alaquainc method is a best crystallization used in some specialized cases. Crystallizers cooling in saturated solutions are allowed to cool in open tanks. Scraped surface of one type crystallizes is the Swenson-Walker crystallizes, Scraped surface crystallizers in which consists of an open trough 0.6m wide with a semicircular bottom having a cooling jacket outside.
An internal agitator is fitted with spring-loaded scrapers that wipe the wall and provide good heat-transfer coefficients. The crystals removed mother liquid is drained after a period of time and the. Difficult to control crystals size are Nucleation. Typically, labor costs are very high. The crystal-size distribution somewhat wide product generally used.
Also called a violator, this type of crystallizer is used in crystallizing ice cream and plasticizing margarine. Cooling water passes in the annular space the growing crystals on turning a slow-speed spiral agitator rotate and suspends. The break and blades pass close to the wall off any deposits of crystals on the cooled wall Double-pipe scraped surface crystallizer.
Circulating-liquid Crystallizers evaporative.
Continuous oscillatory baffled crystallizer (COBCTM) the heated liquid then flows into the vapor space, where flash evaporation occurs, giving some super saturation. The vapor leaving is condensed. The suspension or magma of crystals is circulated out of the main body through a circulating pipe by a screw pump. The magma flows though a heater, where its temperature is raised 2-6 K. The saturated liquid is leaving then goes back as a recycle stream to the heater, where it is joined by the entering fluid. Also called Crystallizers Oslo the supersaturated liquid flows down the down flow tube and then up through the bed of fluidized and agitated crystals, which are growing in size.
Circulating-magma Crystallizers vacuum. Here super saturation is reached by evaporation. The crystal is larger settle out and slurry of Crystallizer and mother liquid is withdrawn as a product. The boiling occurs at the liquid surface heated liquor then mixes with body slurry and allowing controlled cooling profiles, e.g. linear, parabolic, discontinued, step-wise or For further information see oscillatory baffled reactor. The vapors leave through the top. A steam-jet ejector provides vacuum.
The circulating liquid is drawn by the screw pump down inside the tube side of the condensing stream heater. That offers plug flow under laminar flow conditions (low flow rates) with superior heat transfer coefficient this gives much better control over crystal size, morphology and consistent crystal products. The COBCTM is a tubular baffled crystallizer this causes super saturation in the swirling liquid near the surface, which deposits in the swirling suspended crystals until they leave again via the circulating pipe.
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