A stacked type falling film evaporator includes a first evaporator, a second evaporator, a first vapor recovering device, a second vapor recovering device and a vapor recompressor. The first evaporator and the second evaporator respectively have evaporation tubes of a length of 5 m to 10 m, and are stacked in such a manner that wastewater passes through the first evaporator and the second evaporator in order. The first vapor recovering device collects vapor generated from the wastewater in the first evaporator and supplies the collected vapor to the second evaporator. The second vapor recovering device collects vapor generated from the wastewater in the second evaporator and supplies the collected vapor to the first evaporator. The vapor recompressor compresses the vapor collected in the second vapor recovering device before the vapor is supplied to the first evaporator.

A method for preparing nickel/manganese/lithium/cobalt sulfate and tricobalt tetraoxide from battery wastes adopts the following process: dissolving battery wastes with acid, removing iron and aluminum, removing calcium, magnesium and copper, carrying extraction separation, and carrying out evaporative crystallization to prepare nickel sulfate, manganese sulfate, lithium sulfate, cobalt sulfate or/and tricobalt tetraoxide. By using the method, multiple metal elements, such as nickel, manganese, lithium and cobalt, can be simultaneously recovered from the battery wastes, the recovered products are high in purity and can reach battery grade, battery-grade tricobalt tetraoxide can also be directly produced. The method is simple in process, low in energy consumption and free in exhaust gas pollution, and can realize zero release of wastewater.

Methods and systems for treating brine to produce distilled water and dried NaCl are disclosed. The brine enters a crystallization plant and is heated. Once heated, the brine is circulated to an evaporator. The evaporator increases the concentration of NaCl in the brine to a point about the super saturation level. Once above the super saturation level, NaCl crystals are formed. The larger crystals are circulated to a centrifuge for drying and the smaller crystals are recirculated through the evaporator for continued growth. The NaCl crystals are dried in the centrifuge.

The present disclosure relates to processes for treating an aqueous composition comprising lithium sulfate and sulfuric acid. The processes comprise evaporatively crystallizing the aqueous composition comprising lithium sulfate and sulfuric acid under conditions to obtain crystals of lithium sulfate monohydrate and a lithium sulfate-reduced solution; and optionally separating the crystals of the lithium sulfate monohydrate from the lithium sulfate-reduced solution. The processes optionally further comprise concentrating the lithium sulfate-reduced solution under conditions to obtain an acidic condensate and a concentrate comprising sulfuric acid.

A resin containing a desirable compound is extracted from plant material and dissolved in a volatile non-polar solvent. The solvent is evaporated, cooling the solution and increasing the saturation level of the compound in the solution. A second volatile non-polar solvent, in which the compound is less soluble, is then added to the solution and evaporated. This again cools the solution and increases the saturation level until the compound has started to crystallize. The crystals are then filtered and rinsed. Crystallization is more rapid compared to traditional techniques. The resin is obtained from the plant material using an extraction solvent to form a solution, which is then floated above an immiscible liquid, where it is drawn off through a screen and the extraction solvent evaporated.

The invention relates to a process for the preparation of alkali metal cyanides as a solid substance, comprising the steps of: i) an absorption step in the form of an absorption of hydrogen cyanide from a hydrogen cyanide-containing synthesis gas in an aqueous alkali metal hydroxide solution; ii) a crystallization step in the form of introducing said alkali metal cyanide solution into an evaporative crystallizer; iii) a separation step; iv) a recycle step; v) a drying step.

Methods and systems for treating brine to produce distilled water and dried NaCl are disclosed. The brine enters a crystallization plant and is heated. Once heated, the brine is circulated to an evaporator. The evaporator increases the concentration of NaCl in the brine to a point about the super saturation level. Once above the super saturation level, NaCl crystals are formed. The larger crystals are circulated to a centrifuge for drying and the smaller crystals are recirculated through the evaporator for continued growth. The NaCl crystals are dried in the centrifuge.

The present invention relates to the extraction of lithium from liquid resources, such as natural and synthetic brines, leachate solutions from clays and minerals, and recycled products.

An organic compound refinement method for refining a specific organic compound which is a target compound from at least two types of organic compounds. The method includes separating the target compound from an organic compound other than the target compound while the at least two types of organic compounds are irradiated with light at an infrared absorption wavelength of a specific functional group that is not contained in the target compound but is contained in the organic compound other than the target compound, or separating the target compound from an organic compound other than the target compound while the at least two types of organic compounds are irradiated with light at an infrared absorption wavelength of a specific functional group that is contained in the target compound but is not contained in the organic compound other than the target compound.

The invention relates to a processing device in the form of a crystallizer or reactor comprising a tube, at the opposite end regions of which an inlet and an outlet are provided for a crystallization or reaction medium. A helixical web is provided which runs about a longitudinal axis of the tube and which rests against the inner face of the tube casing, and the web is mounted so as to be rotatable about the aforementioned longitudinal axis of the tube. The device also has a drive for rotating the web.