A crystallizer is a processing device used to concentrate feed into stable crystals and clean water. A solid-liquid separation technique in which solid crystals are produced from a liquid solution is known as crystallization. Crystallizers can remove liquid wastes completely, resulting in zero liquid discharge (ZLD). Primary nucleation and secondary nucleation are the two steps of crystallization. The formation of new crystals is referred to as primary nucleation. Secondary nucleation is the primary stage that results in the mass processing of crystals. There are two types of crystallization processes: evaporative crystallization and cooling crystallization.
Crystallizers can be used on their own or in conjunction with other technologies like evaporators. Evaporators that use steam to drain water from a solution are known as steam evaporators. Evaporation concentrates a liquid by heating the solution, which is usually water. A wastewater concentrator is a form of evaporator that is used to convert waste-saturated industrial wastewater into purified water that can be reused. AlaquaInc is the crystallizers supplier in the USA, along with other processing equipment to meet the industrial processing equipment requirements.
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Types of Crystallizers
The different types of crystallizer for different processing requirements are:
- Forced Circulation Crystallizer: The vapor recompression principle (thermal or mechanical) is often used in forced circulation crystallizers, which may be single or multiple effects. They usually run in the range of low vacuum to atmospheric pressure. In general, these units are used when crystal size isn’t critical or when the crystal expands at a reasonable pace. Depending on the application, almost every building material may be used for the fabrication of these crystallizers.
- Oslo Type Growth Crystallizer (classified-suspension crystallizer): The oldest design for producing huge, coarse crystals is the Oslo style crystallizer, also known as classified-suspension crystallizer. The architecture relies on desupersaturating the mother liquor by contacting the larger crystals in the crystallization chamber and holding the majority of the crystals in suspension without the use of a stirring system, allowing for the processing of large crystals with a narrow size distribution.
- Cooling Crystallizer: The solubility of a compound in certain solutions increases as the temperature rises. The mixture becomes supersaturated as saturated solutions cool, and crystallization begins. The main benefits of cooling crystallization are high crystal size uniformity and energy consumption. The elimination of heat supply for evaporation results in significant energy savings. Flash cooling is a typical form of crystallization cooling in which a portion of the liquid is evaporated, eliminating latent heat and allowing cooling.
- Evaporative Crystallizer: The solution containing the solvent and the soluble portion to be crystallized is heated until the solvent evaporates in evaporative crystallization. Since the higher dosage exceeds the chemical compound’s solubility, the molecules of the soluble compound break out as crystals as the solvent evaporates. When dealing with common compounds including inorganic salts and sucrose, this is the most popular method of crystallization. The heat supply is normally steam, and forced circulation is usually used in such crystallization units. The transformation occurs at essentially isothermal temperatures because evaporation is the primary mechanism involved.
- Vacuum Crystallizer: Vacuum cooling crystallization is primarily used for salts that lose solubility as temperature rises. The strain is steadily lowered, causing the solvent (water) to evaporate and the solution to cool to its boiling point. Salt crystallizes as the temperature is lowered. Air sucked in at the bottom of the crystallizer (air agitation) keeps it suspended and transports it to the outlet.