A process for removing impurities from a crystallized metal sulfate, including contacting crystallized metal sulfate with a liquor rich in metal sulfate. The metal may be cobalt, nickel, or manganese, and the impurities may be magnesium or calcium. The liquor rich in metal sulfate may be an overflow liquor from crystallization of the metal sulfate, and said overflow liquor may be subject to one or more impurities removal steps prior to contacting the crystallized metal sulfate, such that the overflow liquor contains lower levels of impurities than the crystallized metal sulfate to be contacted. A counter-current wash circuit may be used to remove impurities from a crystallized metal sulfate, whereby a plurality of washing tanks are configured to receive crystallized metal sulfate in a sequence, and washing liquor in reverse of said sequence.

A system for generating a concentrated product from a feedstock includes a feedstock chamber to which the feedstock is provided, a heat exchanger assembly in thermal communication with the feedstock chamber, the heat exchanger assembly being configured to freeze the feedstock in the feedstock chamber, an output flow arrangement configured to carry liquid from the feedstock chamber as the feedstock thaws, the output flow arrangement comprising a flow controller, a sensor disposed along the output flow arrangement or the heat exchanger assembly, the sensor being configured to measure a characteristic of the liquid, the characteristic being indicative of a solute concentration level of the liquid or the heat exchanger assembly, and a processor responsive to the characteristic and configured to control the flow controller to, based on the solute concentration level, direct the liquid passing through the output flow arrangement to define a plurality of products at different concentration levels, the plurality of products comprising the concentrated product.

Disclosed is a system for producing magnesium hydroxide including: a generation unit; and a recovery unit connected to the generation unit, wherein the generation unit has a reaction tank in which a calcium hydroxide slurry is added to water to be treated containing magnesium ions to crystallize magnesium hydroxide and to obtain a reaction slurry containing particles of magnesium hydroxide, and a sedimentation tank in which the reaction slurry is reserved to sediment the particles and to separate the reaction slurry into a separation slurry containing the particles at a high concentration and a separation liquid containing the particles at a low concentration, and wherein, in the recovery unit, an alkaline aqueous solution is added to the separation liquid to crystallize magnesium hydroxide and to obtain the reaction slurry and then the reaction slurry is reserved to sediment the particles and to recover the sedimented particles.

The present invention relates to means and methods for producing crystals or crystalline substances in a contained vessel. In particular, crystals or crystalline substances, which are useful as pharmaceutical ingredients, can be manufactured.

A method for crystallization of β-ammonium tetramolybdate includes: performing a stepwise pH-adjusting treatment of an ammonium molybdate solution via zoning to obtain the β-ammonium tetramolybdate. When feeding the ammonium molybdate solution into a reaction system from a first zone and then into second to sixth zones successively, pH.sup.1 of a resultant solution in the first zone is 7.0-6.0; pH.sup.2 of a resultant solution in the second zone is less than 6 and greater than or equal to 4; pH.sup.3 of a resultant solution in the third zone is less than 4 and greater than or equal to 2.5; pH.sup.4 of a crystallized slurry in the fourth zone is less than 2.5 and greater than or equal to 1; pH.sup.5 of a crystallized slurry in the fifth zone is 2.5-4.0; and pH.sup.6 of a crystallized slurry in the sixth zone is less than 2.5 and greater than or equal to 2.0.

A method for managing crystallization process in a process control plant is provided. The method includes capturing process parameters of an operating reactor unit in a process control plant. The method includes predicting desired process parameters based on first set of parameters and the captured process parameters. The first set of parameters includes information related to process dynamics and process disturbances associated with the operating reactor unit. Furthermore, the method includes controlling process control loop associated with the operating reactor unit based on the desired process parameters and the first set of parameters.

A device for purifying a product by crystallization includes: a feed unit having a solution in which the total product concentration is substantially completely dissolved or a suspension with the total product concentration; a crystallization unit in which the product crystallizes and forms a solids content; a separation unit in which the crystallized product is separated from the solution or suspension; a temperature control unit for controlling temperature at least in the feed unit and/or the crystallization unit; and a control and evaluation unit that determines the total product concentration and/or the concentration of the solids content and/or the concentration of the dissolved product content and/or the concentration of an impurity content, taking into account the measured values of connected temperature sensors and of connected impedance sensors.

The invention relates to a cooling crystallizer (2.0) for saccharose magma in a vertically oriented container (2.1) which has an upper inlet (2.2) for supplying magma and a lower outlet (2.3) for discharging magma, comprising multiple cooling blocks (5.0) which are mutually spaced in a vertical direction. A heat carrier fluid flows through the cooling blocks (5.0), and the cooling blocks are coupled to a heat exchanger in order to dissipate heat from the magma, wherein multiple cooling blocks (5.0) are combined to form a cooling packet (5.1; 5.2), and the cooling packets (5.1; 5.2) are designed as separate cooling circuits with separate heat exchangers (2.1.2; 2.2.2).

Zero liquid discharge systems, processes, and techniques for treating a saltwater without evaporative crystallization. The saltwater is treated by a fluidic circuit comprising a high-pressure reverse osmosis (“HPRO”) unit configured to operate at a hydraulic pressure of at least 1,500 psi, a cooling crystallizer, and a solids-liquid separator. The saltwater is first concentrated by the HPRO unit to produce an HPRO brine, which is subsequently cooled to a designated crystallization temperature by the cooling crystallizer. The cooling crystallizer crystallizes salt crystals from the cooled HPRO brine and produces a salt-diminished brine. The solids-liquid separator separates the salt-diminished brine from the salt crystals. The salt-diminished brine from the solids-liquid separator is returned to the HPRO unit for further treatment, which allows additional salts to be crystallized from the returned salt-diminished brine.

A method for crystallization of β-ammonium tetramolybdate includes: performing a stepwise pH-adjusting treatment of an ammonium molybdate solution via zoning to obtain the β-ammonium tetramolybdate. When feeding the ammonium molybdate solution into a reaction system from a first zone and then into second to sixth zones successively, pH.sup.1 of a resultant solution in the first zone is 7.0-6.0; pH.sup.2 of a resultant solution in the second zone is less than 6 and greater than or equal to 4; pH.sup.3 of a resultant solution in the third zone is less than 4 and greater than or equal to 2.5; pH.sup.4 of a crystallized slurry in the fourth zone is less than 2.5 and greater than or equal to 1; pH.sup.5 of a crystallized slurry in the fifth zone is 2.5-4.0; and pH.sup.6 of a crystallized slurry in the sixth zone is less than 2.5 and greater than or equal to 2.0.