Using potassium chloride (KCI) as starting material
Evonik produces potassium hydroxide (KOH) in an electro-chemical process.
The first step in Caustics Distribution is to collect and store the sodium and potassium hydroxide solutions generated during electrolysis, adjust the concentration, and then distribute and/or dispense the materials into tank trucks, containers, tank cars, and ships.
The potassium carbonate plant begins by carbonating a 50% potassium hydroxide solution with CO2 from steam generation flue gas. The produced K2CO3 solution is sold to customers or is used as raw material for the production of K2CO3 in solid form.
The solution is boiled down, causing potassium carbonate to crystallize out of solution. The salt slurry is next separated from the mother liquor via centrifugation and then dried and calcined, whereby the calcined product is sold either as a granulate or a powder. Product that is separated out prior to calcination and only dried is sold commercially as a hydrated.
Products are dispensed into silo trucks and cars, bulk bags, small containers, and sacks.
Potassium hydroxide is used in the bicarbonate plant, where it reacts further with CO2 from the flue gas.
(Potassium) bicarbonate processing is similar to potassium carbonate processing in that salt is first separated from the mother liquor via centrifugation and then dried.