Manufacturing Methods of Calcium Chloride
Calcium chloride is a widely used chemical, mainly used as a raw material for production. It has a variety of manufacturing methods, and three common manufacturing methods will be introduced in detail here: acid digestion, alkali digestion and complex decomposition method.
I. Acid digestion method
Acid digestion method is to react limestone with hydrochloric acid to produce calcium chloride and water. This method has the advantages of simple process, convenient operation and low cost, but the resulting wastewater contains more chloride ions and needs to be treated before discharge.
The specific steps are as follows:
1. Crush the limestone to a certain size and mix it with hydrochloric acid in a certain proportion.
2. In the reactor, control a certain temperature and pressure, so that the limestone and hydrochloric acid fully react.
3. After the reaction is completed, remove the unreacted limestone by filtration to obtain calcium chloride solution.
4. The calcium chloride solution is evaporated and concentrated, cooled and crystallized, and separated to obtain calcium chloride products.
II. Alkali-dissolution method
Alkali-dissolution method is to react calcium hydroxide with hydrochloric acid or chlorine gas to produce calcium chloride and water. The advantage of this method is that the concentration of chlorine ions in the wastewater produced is lower, but more calcium hydroxide needs to be consumed.
The specific steps are as follows:
1. Mix calcium hydroxide with water in a certain proportion to make a suspension.
2. Pass in hydrochloric acid or chlorine, control a certain temperature and pH, so that calcium hydroxide and hydrochloric acid or chlorine fully reacted.
3. After the reaction is completed, filter to remove the unreacted calcium hydroxide and obtain calcium chloride solution.
4. The calcium chloride solution is evaporated and concentrated, cooled and crystallized, and separated to obtain calcium chloride products.
Third, compound decomposition method
Compound decomposition method is to use calcium carbonate and hydrochloric acid reaction to generate calcium chloride, water and carbon dioxide. The advantage of this method is that the concentration of chlorine ions in the wastewater produced is lower, but more calcium carbonate needs to be consumed.
The specific steps are as follows:
1. Mix calcium carbonate with hydrochloric acid in a certain proportion to make a slurry mixture.
2. In the reaction kettle, control a certain temperature and stirring speed, so that calcium carbonate and hydrochloric acid fully react.
3. After the reaction is completed, filter to remove the unreacted calcium carbonate and carbon dioxide gas to obtain calcium chloride solution.
4. The calcium chloride solution is evaporated and concentrated, cooled and crystallized, and separated to obtain calcium chloride products.
The above three methods have their own advantages and disadvantages, and the choice of which method to use depends on factors such as the source of raw materials, production costs and environmental requirements. No matter which method is used, the reaction conditions need to be controlled to ensure product quality and production safety. At the same time, the wastewater produced also needs to be properly treated to avoid pollution of the environment.
In short, the manufacturing methods of calcium chloride need to be selected and optimized according to specific conditions to achieve the purpose of improving product quality, reducing production costs and protecting the environment.
