Meishen Technology Company
How
to prepare magnesium sulfite into magnesium sulfate
Magnesium
sulfite is a by-product of magnesium desulfurization, usually with 6 crystal
water. A power plant can produce as little as 100,000 tons of magnesium sulfite
every year, and as many as hundreds of thousands of tons or even millions of
tons. Because there is no reliable way to use them, most of them are processed
by accumulation and storage, which not only takes up cultivated land, but also
causes environmental pollution.
The
treatment of magnesium sulfite includes the calcination method to produce
magnesium oxide and recover sulfuric acid, the sulfuric acid acidification
method to produce magnesium sulfate heptahydrate and liquid sulfur dioxide, and
the purification method to purify magnesium sulfite to produce high-purity
magnesium sulfite. Catalytic oxidation of magnesium sulfite, catalytic
oxidation of magnesium sulfate heptahydrate by evaporation, concentration and
crystallization, etc. However, due to the long process, high cost, serious
secondary pollution, and product sales bottlenecks in the above processes, most
of them have not been industrialized.
Put
magnesium sulfite from a certain power plant into an oxidation reactor, mix it
with the mother liquor from the production process of magnesium sulfate
heptahydrate, and then heat it up under agitation and oxidize with air. After
about 3 hours of oxidation, the oxidation reaction has been completed and
filtration is started. The clear liquid obtained by the filtration is directly
sent to the magnesium sulfate heptahydrate crystallizer, and vacuum cooling is
used for cooling and crystallization.
When
the crystallization temperature drops to 47°C, an energy conversion agent is
added, and then continuous cooling is performed. The cooling process totaled
about 3 hours, and the crystallization was completed. The operator opens the
discharge valve for separation, and the obtained magnesium sulfate heptahydrate
is sent to the drying process to be dried and packaged to obtain the finished
product of magnesium sulfate heptahydrate. The obtained magnesium sulfate
mother liquor is sent to a storage tank for storage, and is recycled as a
batching liquid in the oxidation process.
The
obtained magnesium sulfate heptahydrate is further sent to the anhydrous
magnesium sulfate production process, first dehydrated to obtain magnesium
sulfate monohydrate, and then enhanced dehydration to obtain anhydrous
magnesium sulfate, the obtained product is as white as snow, reaching the feed
grade standard.
The
process used is simple, the process is short, the equipment is not complicated,
the operation process does not need to add a catalyst, the magnesium sulfate
crystallization process does not need to consume steam or electricity for
evaporation, the production process is fast, the energy consumption is
particularly low, and it does not pollute the environment.