Combination preparation method for anhydrous magnesium chloride and potassium sulphate

Abstract

The present invention provides a combined preparation method of a waterless magnesium chloride and a potassium sulfate and meanwhile produces a hydrochloride. The technic proposal is that a hexahydrated magnesium chloride (MgCl2 question mark 6H2O) is dehydrated to a dihydrated magnesium chloride. A hydrogen chloride dry gas is dried and dehydrated to a waterless magnesium chloride in a fluidized bed. The second step is that after a heat transfer, a dehydrated hydrogen chloride tail gas enters into a drying tower of a concentrated sulfuric acid and an oleum and the tail gas is dehydrated. The dried hydrogen chloride is recycled. After absorbing the water, a dilute sulfuric acid enters into a sulfate production device to absorb a sulfur trioxide again and becomes the concentrated sulfuric acid. The redundant dilute sulfuric acid enters into a Mannheim device to produce a potassium sulfate and the produced hydrogen chloride produces the hydrochloride after being cleansed. The technology producing the waterless magnesium chloride, provided by the present invention, has the advantages of low cost, good quality, high purity quotient, low energy consumption and little environmental pollution.

Description

technical field [0001] The present invention relates to a kind of preparation method of chemical, relate in particular to a kind of using magnesium chloride hexahydrate (MgCl 2 ·6H 2 O) prepare anhydrous magnesium chloride, the technique of co-producing potassium sulfate and hydrochloric acid simultaneously. Background technique [0002] my country is a country rich in sea and lake salt resources, and magnesium in sea and lake salt is the resource second only to sodium in reserves. Taking Qaidam Salt Lake as an example, the magnesium salt reserves are as high as 4.81 billion tons. For a long time, the utilization of sea and lake salt resources has mainly focused on salt production or potassium extraction. In the process of potassium extraction, the average by-product of 1 ton of potassium chloride is about 10 tons of magnesium chloride. Due to insufficient attention in production technology and deep processing, the production process A large amount of high-magnesium brine...

AI Technical Summary

Problems solved by technology

[0007] The present invention mainly solves the technical problems of high production cost, cumbersome process operation and serious environmental pollution in the prior art.