|Limestone-Hydrochloric Acid Process|
Limestone can be treated with hydrochloric acid to form calcium chloride and carbon dioxide:
If concentrated (36%) hydrochloric acid is utilised, the concentration of CaCl2 in the produced solution will be approximately 40% and further evaporation is only needed when flakes are produced. The purification of the product is mainly accomplished by adding Ca(OH)2 as described in the natural brine process.
The high purity of the produced carbon dioxide (CO2)makes it suitable for applications within the food and pharmaceutical industries e.g., in the production of carbonated soft drinks.
The limestone process is utilised for calcium chloride production in our Helsingborg, Sweden (view process), Kokkola, Finland (view process) and Frankfurt, Germany (view process) facilities. The limestone comes from Gotland in the Baltic Sea and the hydrochloric acid is produced at neighbouring chemical plants.
Extremely pure calcium chloride products can be obtained using this process if the purity of the hydrochloric acid and limestone is sufficient. Hence, the process is well suited for producing food grade products. It is also an environmentally friendly method to utilise by-product hydrochloric acid.