ASC’s state-of-the-art integrated Chlor-Alkali to Polyvinyl Chloride production complex consists of three main processes.
In the first process, the Chlor-Alkali Process, caustic soda is the main product along with chlorine gas, hydrogen gas and sodium hypochlorite solution as by-products.
In the Chlor-Alkali plant, common salt (sodium chloride, NaCl) is dissolved in water and purified. The purified concentrated salt solution is then electrolyzed utilizing the sophisticated cationic exchange membrane technology developed by Asahi Glass Company (AGC) to produce caustic soda, chlorine gas and hydrogen gas. Sodium hypochlorite is a derivative product obtained by reacting caustic soda and chlorine. ASC enjoys the benefit of the most environmentally friendly Chlor-Alkali technology consuming minimum energy, producing no pollution and delivering superior product quality.
The second process, the EDC/VCM Process, produces vinyl chloride monomer (VCM) as the main product. Commercial EDC/VCM Process consists of two type of processes, the Direct Chlorination process and the Oxy-Chlorination process. In Direct Chlorination process, chlorine generated in the Chlor-Alkali process is reacted with ethylene to produce ethylene dichloride (EDC), an industrial solvent used mainly to produce VCM.
In the Oxy-Chlorination process, ethylene, hydrochloric acid and oxygen are reacted to give ethylene dichloride.
Ethylene dichloride is then subjected to “cracking” process to give VCM and hydrochloric acid (HCl) as by-product. Some of the produced hydrochloric acid is utilized in the Oxy-Chlorination process to produce VCM, while the rest is delivered to customers.
And in the third process, the PVC Process, VCM is polymerized to produce polyvinyl chloride (PVC) resin in batch reactors. After polymerization, VCM is stripped from the resin and the resin is finaly dried to produce high quality PVC resin which fulfills the international health and hygiene standards and technically satisfies highly demanding applications.