Our environmental care
We have an environmental management system in place since 2001 that meets the requirements of the international standard ISO 14001. The environmental management system obliges us to take a structured approach to our environmental care, starting with the identification of the important environmental aspects to which we must pay attention. Our environmental management system is audited each year by an external independent organization that assesses whether we continue to meet all standard requirements and whether we continue to improve on our environmental management. The ISO 14001 certificate provides a guarantee to all external stakeholders, such as residents, surrounding companies, authorities, suppliers, and customers, that ‘sustainable development’ is not a hollow phrase for us.
Our energy care
We have an energy management system in place since 2017 that meets the requirements of the international standard ISO 50001. The energy management system obliges us to take a structured approach to our energy care. Our energy management system is audited each year by an external independent organization that assesses whether we continue to meet all standard requirements and whether we continue to improve on our energy management. The ISO 50001 certificate provides a guarantee to all external stakeholders, such as residents, surrounding companies, authorities, suppliers, and customers, that ‘energy efficiency’ is not a hollow phrase for us.
By-products, residues, and waste materials
We strive towards avoiding the generation of waste as much as possible and converting all substances that are produced and used during the production of steel into products that can serve as raw materials in other industries or that have a useful application.
By-products
By-products are materials that are either reused as a raw material or used as a synthetic end product as an alternative to e.g., natural stone.
An important source of by-products is liquid slag formed at high temperatures in our steel production process.
The slag that is formed in our blast furnaces is granulated into blast furnace sand by means of powerful water jets. The cement industry mixes this granulated blast furnace sand with cement clinker to produce metallurgical cement (CEM III). This is used in concrete for hydraulic engineering pillars and for applications where rapid hardening of the cement is required. A small proportion of air-cooled blast furnace slag is used in road construction as a foundation material and as a basic raw material for the production of insulation wool.
LD slag is produced in the steel shop. After deferrization, this steel slag is sieved into different grain sizes, to convert them into commercial end products. LD slag can be used for sustainable paving of, for example, car parks and roads. Coarser fractions of more than 32 mm are a valuable option for broken gravel and for hydraulic engineering works. Part of the finer fractions, smaller than 10 mm, is recycled via our sinter plant in the blast furnace, as a substitute for limestone.
We separate tar, benzol and sulphur from the coke oven gas in our by-products’ facilities. Once separated, they are used as raw materials in the chemical industry.
Coke oven gas, blast furnace gas and converter gas are all to be used as fuel in our production processes, as a substitute for natural gas. What we are unable to use ourselves is sent to ENGIE's neighbouring power station to be converted into electricity.
Residues
Residues are mainly residues containing ferrous oxide and carbon which are inevitably formed during our production process, and which are separated from a gas or water flow in our dust separator or water treatment plants.
We strive to maximize the re-use of our residual materials, considering process-technical requirements and a possible impact on the environment. By re-using materials, we make more efficient use of natural resources, save on expensive raw materials, and avoid having to dispose of them in landfills.
Both internally recycled and externally purchased scrap is melted down in the converter of the steel shop, where we produce liquid steel which is subsequently solidified into steel slabs. All external scrap deliveries are checked by specialized controllers for non-conform scrap and non-ferro materials. All approved deliveries are unloaded on the scrap yard, from where the material is loaded in scrap transports as designated by the steel shop.
Since 2021 a scrap cleaning machine, operated by Oxytec, is active on site. The goal of this step is to upgrade the quality of certain types of scrap by screening and metallic separation before being sent to the scrap yard for further processing.
Waste materials
Waste materials are materials that cannot easily be re-used. We collect them selectively. Most waste materials are recovered by accredited processors. Only a relatively small quantity is dumped or incinerated. Some examples:
We selectively collect clean and pure wood waste from, for example, packaging. This wood waste is then to be used as a raw material to produce chipboard.
We are also processing non-recyclable waste wood into biocoal at the Torero plant. We will inject this biocoal into our blast furnaces. This reduces the injection of fossil pulverized coal and lowers our CO2 emissions.
We collect PMD selectively to give it a new life through recycling.
Converter sludge comes from the wet gas scrubbing of the converter gas. The coarse converter sludge (from the pre-settling tank) is converted into briquettes, which are reused in the converter (to replace scrap). The fine converter sludge (from the settling tank) is first pressed into ‘filter cake’ and then partly used internally as a raw material (via the pre-bedding of the sinter plant). The part we cannot recycle internally is recovered in the cement industry where it is used as a raw material for clinker production.
The sleeve filter dust comes from dedusting in the sinter plant. As no internal or external useful application has been found at present, we are obliged to dispose of this waste stream in a landfill.
