WACKER’s integrated production system, primarily based on silicon and ethylene as starting materials, is one of our greatest strengths. In our integrated processes, we optimize the number of materials used, and combine, process and recycle them. Normally, by-products are immediately processed further and used in other production areas. Take, for example, our integrated silicon production system. Although it comprises just four starting materials – silicon, methanol, hydrogen and salt (sodium chloride) – it enables us to manufacture over 3,000 silicone products, as well as pyrogenic silica and polysilicon. And in our integrated ethylene production system, we use ethylene to generate organic intermediates, which we then turn into polymer dispersions and dispersible polymer powders.
A focal point of our integrated production is to minimize hydrogen chloride consumption. Hydrogen chloride is an essential auxiliary in the manufacture of chlorine-containing inter-mediates. Its production requires a lot of energy and is therefore expensive. In our integrated material loop, hydrogen chloride is recovered as a by-product when the chlorine-containing intermediates are converted to chlorine-free end products (e.g. hyperpure silicon or pyrogenic silica). The hydrogen chloride is returned to the production loop and reused. This closed material loop reduces emissions and, due to lower raw-material consumption, transportation.
Zhangjiagang in China has joined Burghausen and Nünchritz as our third integrated production site. In Zhangjiagang, WACKER and Dow Corning Corporation commissioned a production facility for pyrogenic silica and siloxanes in November 2008. By the end of 2010, it is set to reach an annual capacity of 200,000 metric tons. The new plant uses state-of-the-art environmental technology and is run in accordance with strict international safety, health and environmental-protection standards.