A system and method for cleaning of a forced-circulation evaporative crystallizer. The crystallizer is used to produce salt solids and includes a circulation pump, a heat exchanger, a separator, and a vapor processor. Solids deposits accumulate during salt solids production within at least one of the circulation pump, heat exchanger, and separator. A solids deposits metric representative of an amount of the accumulated solids deposits is measured. The solids deposits metric is determined to deviate from a baseline by at least a cleaning threshold. Certain determinations are made based on the solids deposits metric: determining a cleaning mode and at least one of a type of cleaning solution and a duration for which at least one of the circulation pump, heat exchanger, and separator is to be cleaned. At least one of the circulation pump, heat exchanger, and separator is then cleaned in accordance with those determinations.

A Reflux Rinsing apparatus for purifying crystals using solvent vapor through dynamic equilibrium recrystallization. A pressure vessel contains a liquefied gas solvent, impure crystalline starting material initially, and a purified crystalline mass at the conclusion of the purifying process. A mechanism is provided for providing pressure to contents of the pressure vessel and for heating the lower portion thereof. A timer is also connected to the mechanism, the timer being set to heat the pressure vessel to drive vapors and reflux rinsing to remove impurities at the surface of an impure crystalline mass, to reclaim the solvent, leaving purified crystals and impurities in the pressure vessel, and to open the pressure vessel to remove the purified crystals from the vessel walls and bottom surface and to remove the impurities from the vessel. The angle of a crystal bed in the apparatus can be adjusted.

Disclosed herein is a method for continuously preparing crystalline cannabinoid particles. The method includes preparing a cannabinoid-rich solution that comprises a first cannabinoid and inducing the cannabinoid-rich solution to a supersaturated state in which the first cannabinoid has a supersaturated concentration that is greater than a corresponding saturation concentration of the first cannabinoid. The method includes flowing the cannabinoid-rich solution into a continuous stirred-tank reactor (CSTR) in a continuous manner, mixing the cannabinoid-rich solution under turbulent mixing conditions to form a plurality of crystalline cannabinoid particles and a cannabinoid-depleted solution within the CSTR, and discharging the plurality of crystalline cannabinoid particles and the cannabinoid-depleted solution from the CSTR in a continuous manner to provide a flow rate through the CSTR. The method includes separating crystalline cannabinoid particles from the plurality of crystalline cannabinoid particles and the cannabinoid-depleted solution in a continuous manner.

The present disclosure relates to the technical field of wastewater treatment, and provides a wastewater treatment method and apparatus based on hydrate-based water vapor adsorption. The apparatus includes a wastewater evaporation zone, a hydrate formation zone, a hydrate decomposition zone, and a data acquisition and control system. Rising water vapor and condensed water formed during evaporation of wastewater at normal temperature react with a hydrate former on a cooling wall surface to form a hydrate, continuous evaporation of the wastewater is promoted, the hydrate is scraped off to a collecting zone below by a scraper after being formed, and the hydrate is decomposed into fresh water, thereby realizing wastewater treatment. The present disclosure provides a method for treating complex wastewater containing a plurality of pollutants, where water vapor is consumed to form the hydrate to promote wastewater evaporation, and water obtained from the decomposition does not contain pollutants theoretically.

The invention discloses a method and crystallization device for preparing electronic-grade nickel sulfate from nickel powder, and a control method of the crystallization device, and relates to the technical field of non-ferrous metal hydrometallurgy. The method comprises: oxidation, cooling, acid leaching, copper removal, acid adjustment, concentration, cooling crystallization, drying and screening, and secondary leaching: the oxidation comprises: controlling a temperature of nickel powder in a calcining furnace to be 400 C. to 700 C., allowing a use amount of compressed air for each kilogram of nickel powder to be 1 m.sup.3 to 5 m.sup.3, and making the reaction last for 1.0 hour to 2.5 hours; and the acid leaching comprises: placing cooled nickel oxide in a reactor, controlling a temperature to be 45 C. to 70 C., adding dilute sulfuric acid to control a pH value to be 0.5 to 1.5, and making the reaction last for 1 hour to 3 hours.

A device and method for increasing solid holdup in a reaction crystallizer are disclosed. The device includes a discharge pipe, a clear liquid pipe, a clear liquid tank and a gas collecting pipe. A lower end of the discharge pipe is inserted into the crystallizer below the liquid level, while that of the clear liquid pipe is inserted into the clear liquid tank below the liquid level. By using the gas collecting pipe, the reaction crystallizer and the clear liquid tank are communicated all the time. When feeding, a liquid-solid mixture in the crystallizer automatically enters the discharge pipe and flows upward slowly therein, during which solid particles gradually settle down and automatically fall back into the crystallizer while the clear liquid keeps on flowing upward, enters the clear liquid pipe and thereby flows into the clear liquid tank. The clear liquid tank maintains a constant liquid level via overflowing.

The present invention is a method for purifying an NCA, including the steps of: a) dissolving an NCA contaminated with impurities into a solvent which is a good solvent and is not a chlorinated solvent followed by stirring to precipitate an undissolved impurity to afford a suspension, b) adding an acidic filter aid having ability to trap a basic impurity to the obtained suspension followed by filtration and/or forming a fixed bed of the acidic filter aid having ability to trap a basic impurity followed by filtering the suspension to bring the suspension to be in contact with the acidic filter aid having ability to trap a basic impurity, and c) adding the obtained filtrate dropwise to a poor solvent for NCA to crystallize out the NCA in which the impurities are removed. This makes it possible to purify a low-purity NCA conveniently to afford a high-purity NCA.

Disclosed is a method for manufacturing calcium zincate crystals including: placing calcium hydroxide.sub.2 and zinc oxide, one of the precursors thereof, or one of the water mixtures thereof in a starting suspension, the mass ratio of water to calcium hydroxide and zinc oxide, or one of the precursors or mixtures thereof, being greater than or equal to 1; milling the starting suspension to an ambient temperature less than or equal to 50 C. in a wet-phase three-dimensional micro-ball mill for a residence time less than or equal to 15 minutes and in particular from 5 to 25 seconds; recovering a calcium zincate crystal suspension coming out of the mill; and optionally, concentrating or drying the calcium zincate crystal suspension so as to obtain a calcium zincate crystal powder. Also disclosed are uses associated with the calcium zincate crystals obtained according to the method described above.

The present invention relates to the technical field of chemical industry, and in particular to a method for purifying ethylene carbonate through dynamic crystallization, which includes the following steps: adding an ethylene carbonate-containing raw material into a cavity of a crystallization device under a condition of stirring for dynamic crystallization, wherein the crystallization device further includes a jacket attached and circumferentially disposed along the outer wall of the cavity, the jacket is provided with cooling water therein, a temperature of the cooling water is 1-2.5? C. lower than the temperature in the cavity until a granular ethylene carbonate crystal is generated. The present invention using a rake dryer as the crystallization device to realize dynamic crystallization at a certain rotating speed. The technical solution is simple to operate and short in processing cycle, which facilitates improvement in production efficiency and product quality and is suitable for industrial application.

The present invention provides an industrial method production of amorphous posaconazole. The present invention also relates to a method for production of the posaconazole via and novel crystalline forms of posaconazole intermediate. More particularly the present invention relates to novel crystalline forms of posaconazole intermediate and methods for production of novel crystalline forms of posaconazole intermediate represented by the following structural formula III Which is key intermediate in the production of posaconazole. The present invention also provides for the one pot process for the preparation of amorphous posaconazole using novel crystalline forms of benzyl posaconazole. ##STR00001##