Water
Water is an extremely precious resource – not only as drinking water, but also as a raw material, solvent and coolant in many technical and chemical processes. At WACKER, we use water sparingly and protect natural water resources. We always purify our wastewater as effectively as possible and recycle the water by means of cycles in our production. We make sure that this multiple use does not increase energy consumption or otherwise negatively impact the environment.
In both 2017 and 2018, we again used the Global Water Tool™ (GWT) developed by the World Business Council for Sustainable Development (WBCSD) – or the WRI Aqueduct contained in that tool – to analyze the relative water stress index of the countries where our main production sites are located. Beside the water stress index, we are checking whether other water-related risk factors used in this tool are of relevance to WACKER’s production sites. The current result is that 99 percent of our annual water use and over 91 percent of our production volume are in regions with adequate water availability levels.
In 2018, WACKER submitted its first CDP Water Security report (for the reporting year 2017), achieving a D on a scale from A (Leadership) to D (Disclosure). Registered CDP users can download the details.
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2018 |
2017 |
2016 |
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Water use ( thousand m3 ) |
227,510 |
197,430 |
207,930 |
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Cooling water volume ( thousand m3 ) |
211,140 |
180,470 |
197,230 |
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Wastewater volume (thousand m3) |
17,110 |
17,290 |
16,560 |
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COD (chemical oxygen demand) (t) |
1,230 |
1,310 |
1,210 |
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AOX (halogenated organic hydrocarbons) (t) |
2.2 |
2.6 |
3.1 |
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Heavy metals (t) |
1.0 |
1.1 |
1.1 |
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Total nitrogen (t) |
173 |
163 |
200 |
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Total phosphorus (t) |
7.5 |
7.3 |
5.9 |
The very warm summer of 2018 meant we had to increase the throughput of cooling water to keep process temperatures in our Burghausen production plants at the required levels. That led to a 15-percent increase in water consumption. By optimizing waste water treatment at Burghausen, we achieved a reduction of around 6 percent in chemical oxygen demand (COD) and of 14 percent in halogenated organic hydrocarbons (AOX).
Water use declined by around 5 percent groupwide in 2017, mainly due to lower water use at the Burghausen site. Owing to the strong increase in plant utilization at Burghausen, COD rose by around 8 percent in 2017.
The process water used at Nünchritz comes from on-site wells (2018: 4,681,769 m3; 2017: 4,198,940 m3). Drinking water accounts for less than 1 percent of our total water use at this site.
At the Burghausen site, the WACKER BIOSOLUTIONS division improved cooling-water control in the production of VINNAPAS® UW resins. By optimizing the software control, we reduced the use of cooling water by some 46 percent per metric ton of generated product for this product group in 2018. We saved some 37,500 m³ cooling water and will use this optimized control for further savings.
During the reporting period, we improved the site infrastructure at WACKER’s Calvert City dispersion site in Kentucky, USA, with the construction of a new cooling tower. This cooling tower reduces the plant’s water, electricity and chemical usage. The new tower consumes significantly fewer chemicals for water treatment and enables savings in water and electricity consumption.