Hansgrohe has put a recycling plant for chrome-plated plastic showers into operation at its factory in Offenburg. The establishment of a circular economy for plastics fits in with the development of the plant in the south-west, as the production facility has been continuously expanded over the past decades. Sustainable production and renewable energy supply have played a major role in this.
Hansgrohe is probably one of the best-known and largest plastic electroplating companies in the industry. Currently 5448 employees work in plants in France, the USA, China and Germany, where almost half of the workforce is employed. The brand is popular worldwide, which is also reflected in the global turnover of just over EUR 1.5 billion (2023). Exclusive fittings for luxury hotels and luxury liners, for example, are also produced under the Axor brand in a special manufactory.
Location has grown steadily
However, the lion's share of turnover is generated with products such as chrome-plated plastic showers and taps, manufactured in the two plants at the headquarters in Schiltach in the Black Forest and in Offenburg. The plant in Offenburg is still relatively new. Construction of the first section with logistics and plastic injection molding only began in 1990, and numerous areas have been added over the past 30 years. First the shower assembly and the PVD area, then a fittings plant, a logistics expansion and a technical center and, most recently, plastic electroplating in the years between 2017 and 2019. The total area of the plant is over 50,000 square meters and is therefore roughly the size of five soccer pitches.
Sustainability has been taken into account in Offenburg from the very beginning, as is emphasized here. The Offenburg plant generates renewable energy using solar cells and, more recently, wind power. The plant now has a capacity of 10 GW and produces half of its own electricity requirements. The so-called solar tower, which is movable and aligns the solar cells to the sun's rays, also contributes to this. It generates 25 percent more electricity than fixed solar cells.
An employee in the plastic injection molding shop. In the background, a row of plastic showers that are then finished
Plastic substrates for showers and fittings
A mobile transport system (AGV) takes over automated transport tasks in the factory
In the plastic injection molding shop, the showers are first made from ABS plastic in injection molding machines. Granulate made from plastic waste is melted at 160 degrees and formed into the typical shower shape in the injection molding process. The base material of fittings is also made of glass fiber-reinforced plastic, as Jörg Reiff explains. "In the past, there were even lighter mixers than today, but they were not well received by consumers according to the motto 'What weighs nothing is nothing'," recalls the Deputy Head of the Hansgrohe Aquademie training and experience center in Schiltach.
On the way through the various production areas, the so-called mobile transport systems (AGVs) catch the eye. These are transport robots that are connected to the ERP system via WLAN and automatically take over transportation tasks in the plant. Jörg Reiff has observed a significant reduction in forklift accidents following their introduction.
Modern, highly automated coating
In the plastic electroplating department, the plastic showers and other parts are neatly lined up on racks. Here, large transport trolleys move back and forth automatically on rails above the racks in the spacious hall and pick up one of them for coating every seven minutes on average. It then takes over two hours, including manual quality control, before the actual chrome plating or physical vapor deposition (PVD) coating can begin: First, a plastic spray goes through a pickling process. Here, the surface is decomposed in such a way that it is roughened. This is followed by an activator bath in which palladium and tin are absorbed. In the so-called Neo Link treatment, tin is then removed and an electrically conductive surface is created to enable the actual metallization processes: First, a bright copper layer is deposited on the surface, then a nickel layer is added as corrosion protection, and finally chrome plating follows in a fully automated area, predominantly still with chromium(VI). In some cases, chromium(III) is also applied. The coating thickness is 0.2 to 0.3 µm.
With PVD coating, 15 different colors are possible. It is popular because of the additional scratch protection and general durability. "Red gold is particularly popular in Asia," reveals Reiff. The PVD process is booming: there are four systems in Schiltach and four here in Offenburg.
Millions invested in plastics recycling
However, the plant tour was not the main reason for the press event in Offenburg. The reason was the inauguration of a new recycling plant for chrome-plated plastics, which Hansgrohe developed together with Dresden-based plant manufacturer ImpulsTec. The purity of the recycled plastic is said to be 99.8 percent. Hansgrohe attaches great importance to the fact that this environmentally friendly alternative avoids the use of petroleum-based primary plastics. The new plant has so far only been designed for around 100 tons of recycled granulate per year. However, the volume is set to increase over time and pave the way for a circular economy worthy of the term. To this end, recycling is also to be taken into account in the future development of components. So far, however, the plant has only been designed for chrome-plated plastic showers; fittings cannot be recycled. The investment sum amounted to a low single-digit million figure.
Process separates metal and plastic
Project partner ImpulsTec developed the shock wave technology for the current project, which has been running since the end of 2019 and was presented to the public in mid-June. In this process, the chrome-plated parts are exposed to shock waves under water, which cause the metal layer to flake off. The reuse saves costs, energy and water and protects ecosystems, was the tenor of the speeches at the inauguration of the plant. In the meantime, Hansgrohe has already launched its own shower series made from recycled plastic, the "Blended Edition".
Transport trolleys move back and forth on rails and transport racks with plastic showers to pre-treatment and electroplating
The process takes place in several steps: The material is first crushed in a cutting mill and then subjected to an electric charge under water, which separates the metal and plastic. The surface is then decoated and the remaining materials are finally removed by magnetic separation. What remains is the recycled plastic granulate and metal, which flows back into the metal recycling process. "We are in contact with many manufacturers who want to recycle their products," says ImpulsTec Managing Director Stefan Eisert, referring to the demand for such systems.
Chrome plating takes place in a highly automated safety area at the Offenburg plant
Pohl: Step towards a more sustainable future
Finally, the system was put into operation at a symbolic switch button by Hansgrohe Production Director Frank Semling, Hansgrohe Surface Technology specialist David Zapf and ImpulsTec Managing Director Stefan Eisert. "The responsible use of resources is essential," emphasized Frank Semling. The presentations also mentioned that 1.7 Earths are currently required to meet human needs. A plant like this may only be a small step on the way to adapting demand to reality. Hansgrohe, at any rate, believes it has a duty to act and set a good example: "We hope to see imitators who dedicate themselves to the same or a similar technology and have the courage to make investments, even if it takes four or five years. For us, this is one of the steps towards a more sustainable future," says Thorsten Pohl, Vice President Surface Technology Hansgrohe SE, summarizing his company's philosophy.
Speakers at the press event included Chief Production Officer Frank Semling
