Integrated Production

GRI 301-2, GRI 103-2

WACKER’s integrated production system is its greatest strength. Compared with its competitors, WACKER has the key competitive advantage of highly integrated material loops at its major production sites in Burghausen, Nünchritz and Zhangjiagang. Basically, integrated production involves using the byproducts from one stage as starting materials for making other products. Auxiliaries required for this process, such as , are recycled in a closed loop and we utilize waste heat from one process in other chemical processes. The result is lower specific production costs per net production volume compared with open production processes. Integrated production allows us to lower energy and resource consumption, use raw materials more efficiently and, at the same time, integrate environmental protection measures into production processes. Through our integrated production sites, we create synergies in the supply of raw materials and energy.

Our integrated production system is primarily based on salt, and as starting materials. In our integrated processes, we optimize material efficiency by purifying byproducts and reusing them or making them available for external use. Examples:

  • In our integrated ethylene production system, we use ethylene to obtain organic intermediates, which we then turn into dispersions and .
  • Our integrated silicon production system operates along similar lines. Although comprising only a small number of raw materials – silicon, methanol and salt (sodium chloride) – this system enables us to manufacture over 2,800 different products, as well as and .

A further focus of our integrated production is to minimize consumption. Hydrogen chloride is an essential auxiliary deployed in the production of reactive intermediates from energy-poor natural materials. We then use these intermediates to make our end products. Hydrogen chloride production requires a lot of energy. In our integrated material loop, we recover both hydrogen chloride and some of the energy in the form of heating steam during the conversion of the chlorine-containing intermediates to chlorine-free end products (such as hyperpure silicon or pyrogenic ). We then return the recovered hydrogen chloride to the production loop and reuse it. This closed material loop reduces emissions and, due to lower raw-material consumption, shipment journeys.

Integrated Hydrogen Chloride System

We use a chlor-alkali membrane process to supply chlorine, hydrogen, caustic soda and as starting materials to our Burghausen site. This membrane electrolysis has enabled us to stop using mercury-based chlorine electrolysis and simultaneously cut energy consumption by around 25 percent per year. Thus, WACKER has fulfilled the chemical industry’s voluntary commitment to phase out mercury-based processes by 2020 well ahead of schedule.

Examples of savings potential for resources through our integrated production system:

  • We recycle 93 to 96 percent of the hydrogen chloride that we use in the production loops at our Burghausen and Nünchritz sites. During the reporting period, we reduced the HCl loss rate by means of further optimization projects. To achieve this, we put an additional waste-gas recycling facility into operation in the integrated system and optimized waste-gas recycling in the production of pyrogenic silica. The reduction in HCl losses can also be seen in the decline in chloride loading of the Burghausen site’s wastewater by some 1,300 metric tons.
  • In 2016, our integrated production system in Burghausen prevented the of 961,243 metric tons of CO2 equivalents (CO2e) (2015: 917,608 metric tons). Due to this high reutilization rate, less fresh hydrogen chloride needs to be generated and, consequently, there are savings in the transportation of raw materials and in energy consumption.
  • 50 percent of the heat used by Burghausen during the reporting period stems from the site’s integrated heat-utilization system.
  • We optimized the hydrogen loops in our integrated polysilicon production system and thus significantly lowered the consumption of hydrogen extracted from natural gas. This has led to a reduction in emissions of 9,300 metric tons per year compared with 2014.

Zhangjiagang in China – alongside Burghausen (Bavaria) and Nünchritz (Saxony) in Germany – is our third major integrated production site. We employ state-of-the-art environmental technology in China, too, where we operate facilities according to stringent national and WACKER EH&S standards. This also applies to our new site in Charleston in the USA, where we will further optimize our system of integrated polysilicon production.

Silanes
Silanes are used as monomers for the synthesis of siloxanes or sold directly as reagents or raw materials. Typical applications include surface treatment, agents (medically active substances) in pharmaceutical synthesis or coupling agents for coatings.
Silicon
After oxygen, silicon is the most common element on the earth’s crust. In nature, it occurs without exception in the form of compounds, chiefly silicon dioxide and silicates. Silicon is obtained through energy-intensive reaction of quartz sand with carbon and is the most important raw material in the electronics industry.
Ethylene
A colorless, slightly sweet-smelling gas that, under normal conditions, is lighter than air. It is needed as a chemical starting product for a great many synthetic materials, including polyethylene and polystyrene. It is used to make products for the household, agricultural and automotive sectors, among others.
Polymer
A polymer is a large molecule made up of smaller molecular units (monomers). It contains between 10,000 and 100,000 monomers. Polymers can be long or ball-shaped.
Dispersible Polymer Powders
Created by drying dispersions in spray or disc dryers. VINNAPAS® polymer powders from WACKER are recommended as binders in the construction industry, e.g. for tile adhesives, self-leveling compounds and repair mortars. The powders improve adhesion, cohesion, flexibility and flexural strength, as well as water-retention and processing properties.
Silicones
General term used to describe compounds of organic molecules and silicon. According to their areas of application, silicones can be classified as fluids, resins or rubber grades. Silicones are characterized by a myriad of outstanding properties. Typical areas of application include construction, the electrical and electronics industries, shipping and transportation, textiles and paper coatings.
Silica, Pyrogenic
White, synthetic, amorphous silicon dioxide (SiO2) in powder form, made by flame hydrolysis of silicon compounds. Variously used as an additive for silicone rubber grades, sealants, surface coatings, pharmaceuticals and cosmetics.
Polysilicon
Hyperpure polycrystalline silicon from WACKER POLYSILICON is used for manufacturing wafers for the electronics and solar industries. To produce it, metallurgical-grade silicon is converted into liquid trichlorosilane, highly distilled and deposited in hyperpure form at 1,000 °C.
Hydrogen Chloride (HCl)
The chemical industry uses HCl to generate valuable intermediates from organic and inorganic raw materials. The colorless gas dissolves in water to form hydrochloric acid.
Silica
Collective term for compounds with the general formula SiO2 nH2O. Synthetic silicas are obtained from sand. Based on their method of production, a distinction is made between precipitated silicas and pyrogenic silicas (such as HDK®).
Hydrogen Chloride (HCl)
The chemical industry uses HCl to generate valuable intermediates from organic and inorganic raw materials. The colorless gas dissolves in water to form hydrochloric acid.
Chlorosilanes
Compounds of silicon, chlorine and, in some cases, hydrogen. The semiconductor industry mainly uses trichlorosilane to make polysilicon and for the epitaxial deposition of silicon.
Emission
Substance outputs, noise, vibrations, light, heat or radiation emitted into the environment by an industrial plant.
Carbon Dioxide
Chemical name: CO2. This gas naturally constitutes 0.04% of air. Carbon dioxide is generated during the combustion of coal, natural gas and other organic substances. As a greenhouse gas in the atmosphere, it contributes to global warming. Since the start of industrialization in 1850, its concentration in air has risen from approx. 300 to 390 ppm (parts per million). This value is increasing by around 2 ppm every year. Other greenhouse gases are represented as CO2 equivalents (CO2e) based on their greenhouse effect.