Caustic Soda Production Line/Production Plant/Turnkey Project/sodium Hydroxide Production Equipment /NaOH Process

Caustic soda can be produced by ionic membrane process and causticizing process. 

Two methods of production of liquid alkali, tablet alkali, granular alkali, our factory has been doing for many years.

Causticizing process introduction

Sodium  hydroxide,  chemical  formula  is  NaOH, is a strong alkali  with strong corrosiveness, generally sliced or granular shape, which is easily soluble in water (when dissolved in water) and forms an alkaline solution.    , Easy to absorb water vapor  (moisture) and carbon dioxide (deterioration) in the air.

Sodium hydroxide is one of the essential chemicals and one of the common chemicals.    Pure products  are  colorless  and  transparent crystals.    Density 2.130g/cm³.    The melting point is 318.4 ℃ .    The boiling point is 1390 ° C. Industrial products contain a small amount of sodium chloride  and  sodium  carbonate,  which  are  white  opaque  crystals.     There  are  pieces,  sheets, granular and stick -like.

The use of sodium hydroxide is extremely wide.    It is used for papermaking, soap, dyes, artificial silk, aluminum, petroleum refined, cotton fabric finishing, purity of coal scor oil products, as well as food processing, wood processing and machinery industry.

2.    Physical and chemical nature

Sodium  hydroxide  is white translucent  crystalline  solid.     Its  water  solution  has  a  astringent taste and smoothness.

It is easy to solve in the air.    The solid alkali is very hygroscopic, exposed to the air, absorbing the water molecules in the air, and finally fully dissolved into a solution.    It is easy to dissolve in water, and a lot of heat is released when dissolving.    Easy to dissolve in ethanol and glycerin.

Sodium  hydroxide  is  dissolved  in  water  and  will  completely  dissolve  sodium  ions  and hydroxide ions, so it has the generality of alkali.

It can neutralize the pH of any proton acid.

Sodium hydroxide is slightly corrosive on glass products.    The two will generate sodium silicate, making the piston in the glass instrument stick to the instrument.

Introduction to the production process process（苛化法）

Pure alkali and lime are made into pure alkali solution and lime into lime milk, respectively, and reactive reactions at 99 ~ 101 ° C. The severe liquid liquid was clarified and evaporated to more than 40%.    The concentrated solution is further strong and solidly solid to make solid -alkaline products.    Washed mud with water and washed water for alkali.

Na2CO3+Ca(OH)2→

 2NaOH+CaCO3↓

Put pure alkali into the alkali tank to dissolve with water.    The lime is waterized into lime milk and removes impurities.

The alkali and lime milk are measured into the rough barrel, and the reaction reacts is made.

After the reaction reaction, there is a solid generation, and the harsh mud dregs are separated through the three layers of clarification barrels.

The dumping mud is discharged from the bottom of the three layers of clarification barrels.    The filter is filtered into the three -layer of mud washing barrels.    The alkali is washed with water.

After three layers of clarified barrels, the liquid after clarification contains about 10%of NaOH.    A  lot   of  water  evaporates  a  large   amount  of  moisture  through  the   series   of  two  -effect evaporator to obtain about 42%of NaOH.    Alkaline products.

The impurities discharged by the thick braised clarification barrel contain soda.    After filtering the filter, it is sent to the alkali and alkali alkali recycling.

Introduction to ion membrane process

Flow chart