Water: an essential factor in the production process

voestalpine manages one of its most important materials and resources—water—with great care.

Iron and steel production, refining and forming processes: none of these would be possible without the cooling properties of water.

Managing volumes of water

Huge volumes of water are needed at voestalpine, primarily for cooling. The figures illustrate the dimensions involved:

• A “smaller” blast furnace (e.g., Blast Furnace 5 at voestalpine Stahl GmbH in Linz, Austria) requires 2,300 m3 of cooling water a year—this quantity would fill an Olympic-sized swimming pool in less than 90 minutes.
• The Brazilian Sumaré site belonging to Villares Metals S.A. (High Performance Metals Division) draws 22,500 m3 of water a month from rivers, wells, and public water supplies.
• In 2016 voestalpine Stahl Donawitz GmbH returned 24.5 million m3 of treated waste water to the Mur after using it in production…

The workload involved in managing water is considerable: depending on its origin and intended purpose, each liter of water must be filtered and, after being used, treated and returned to rivers at an appropriate temperature.

Water cycles help save water

Water which has already been used once can be repeatedly reused in many different ways. Here we talk of closed water cycles and multiple use. This conserves water resources because less water needs to be drawn, treated, and then returned to the natural environment. The current state-of-the-art is for a maximum of 60% of the process water to be returned to rivers as wastewater .**

Water and environmental protection

The best way to conserve water is to minimize its consumption. This is the goal of many of the investments made by voestalpine companies. During the business year 2016/17, 20% of the voestalpine Group’s environmental expenditure went towards protecting natural bodies of water—a strategy which is being continued this year:

• The closed circuit cooling at the new special steel plant in Kapfenberg reduces the volume of water returned to the Thörlbach by over 90%.
• As a result of technical improvements to the Hot Dip Galvanizing Plant 1, voestalpine Stahl GmbH in Linz saves 150,000 m3 of water annually.
• Villares Metals in Brazil stores process water in two reservoirs, allowing it to reuse around 80,000 m3 of water, almost a third of its annual consumption.

Where engineering structures such as hydropower plants or barrages impact natural water flows, the voestalpine companies take compensatory measures, e.g. installing climbing assistance for aquatic species.

Villares Metals in Sumaré: two reservoirs with a capacity of 11,000 m3 enable process water to be reused.

More on environment: http://www.voestalpine.com/environment