Crystallization method of ferrous sulfate heptahydrate in sulfuric acid method titanium dioxide production process

• Main Author: GONG JIAZHU
• Format: Patent
• Language: Chinese; English
• Published: 12.02.2021
• Subjects: CHEMISTRY; COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSESC01D OR C01F; INORGANIC CHEMISTRY; METALLURGY; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; TRANSPORTING

The invention discloses a crystallization method of ferrous sulfate heptahydrate in a sulfuric acid method titanium dioxide production process, which comprises the following steps: continuously addinga mixed titanium solution into a vacuum crystallizer, carrying out adiabatic evaporation by using vacuum formed by a water ring vacuum pump, removing heat with high enthalpy of heat, and carrying outfirst-step cooling; after cooling in the first step, continuously feeding into a circulating crystallization mixing tank to be mixed with circulating crystallization slurry returned by freezing crystallization, carrying out cooling and crystallization in the second step, and forcibly feeding into a freezing heat exchanger through a circulating pump to carry out heat exchange; cooling to the finalrequired crystallization temperature in the third step; and continuously sending one part of the crystallized slurry to the next process for solid-liquid separation to obtain ferrous sulfate heptahydrate. According to the meth