Thick seawater comprehensive utilization technique after seawater desalination

Abstract

The invention provides a process for comprehensively utilizing desalinated seawater after desalination, including the following steps: the desalinated seawater is collected and potassium is extracted; magnesium is extracted; evaporation concentration is carried out and bromine is extracted; marine gypsum is extracted; salt is made with the desalinated seawater; the desalinated seawater is refined to produce liquid salt. The steps for extracting the potassium, magnesium and bromine of the invention can be inter-modulated. The process has the advantages that: Ca<2+> in saturated brine treated by the process is reduced by 85.21-94.29 percent, Mg<+2> is reduced by 51.22-63.98 percent, SO4<2-> is reduced by 85.57-93.82 percent, Br<-> is reduced by 75 percent, k<+> is reduced by 70 percent, Na<+> is increased by 3.06-5.86 percent and Cl<-> is increased by 7.96-9.38 percent. As ingredient of the brine changes, impendence of the brine evaporation is reduced; yield and quality of the sea salt are improved. The process for producing solar salt can not only effectively utilize chemical resource in the desalinated seawater but also greatly improve the yield and quality of the sea salt product. Bittern quantity of the brine is greatly reduced; if the produced saturated brine is refined, the liquid salt can be produced to directly supply an alkali plant for sintering the alkali.

Description

technical field [0001] The invention relates to a salt-making process and a salinization process, in particular to a process for comprehensive utilization of concentrated seawater after desalination, which can be applied to the comprehensive utilization of concentrated seawater produced after seawater and underground brine are used as raw materials to produce sun-dried industrial salt and the concentrated seawater discharged after seawater desalination . Background technique [0002] In the current production of sea salt, natural seawater is used as raw material, which is gradually concentrated to saturated brine by the action of solar and wind energy, and then continues to evaporate to precipitate sodium chloride crystals. Potassium, calcium, magnesium and sulfate ions in seawater are impurity ions in the production of sea salt, which will not only increase the viscosity and evaporation resistance of brine, and reduce the production of sea salt; Crystal surface, reducing s...

AI Technical Summary

Problems solved by technology

Using concentrated seawater produced by seawater desalination to make salt can increase the yield of sea salt, but the negative impact of the presence of impurity ions on salt production still cannot be removed

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