Research Of The Producing Process Of Light Calcium Carbonate By The Method Of Causticizing

The causticizing method used in the production of caustic soda generates largeamounts of caustic lime mud by product. The purpose of this topic is recycle thecausticizing lime mud, in order to produce light calcium carbonate that in line withthe industry standard.Using the Lime and sodium carbonate as raw material that provided by Gansu××Chemical Co., Ltd., the process conditions of the production of high quality calciumcarbonate was studied systematically. The causticizing and lime slaking processeswere separated, in order to find the best conditions for lime slaking. The effects suchas the stirring rate, particle size of lime, and washing temperature on the causticizingwere investigated. The results show that when the quicklime size is less than100mesh, the mass ratio of gray and water is1:3, the stirring rate is200r/min, and thewater preheated to50℃, as well as the lime and sodium carbonate solution wasclarified via filtration, the yield of calcium carbonate can reach77.4%, reaching thenational standard.Using the caustic lime mud byproduct as raw material that provided by Gansu××Chemical Co., Ltd., the production process for the light calcium carbonate with highquality can be gotten from purification of caustic lime mud. Dissolving wet lime mudwith water with the mass ratio to1:3, followed by washing with10%sodiumcarbonate solution and30%sodium hydroxide solution for2h，and then washing withdissolved and distilled water, respectively. The light calcium carbonate with the yieldof67%in line with national standards can be obtained.The light calcium carbonate prepared was characterized and analyzed bu themethods of XRD, SEM, TG/DTA and national standard HG/T2226-2010.