Porous iron powder is a functional high-tech material, capable of removing multiple contaminants from water and wastewater. Höganäs delivers complete solutions, both for treating drinking water and industrial waste water. The secret is the sponge-like geometry of the iron particles, which gives them a very large reactive surface area.

Höganäs is one of the oldest companies in Sweden. It started out two hundred years ago as a coal mining company, and later developed into a manufacturer of bricks and ceramic products. In the early twentieth century, Höganäs was the first company to successfully reduce iron ore into sponge iron, which was initially produced for the Swedish steel industry. The highly porous iron could readily be comminuted to iron powder, and today Höganäs is the world’s leading producer of metal powders, focusing solely on this product. The annual yearly production of metal powder is 1.4 million tonnes, and Höganäs produces 0.5 million tonnes.

Metal powders are high-technological products, used in a wide spectrum of applications such as sintered car components, welding, water treatment and surface coatings. In several of the applications, metal powder contributes to a better environment by minimising waste and using less energy and materials. Car components can be optimised for weight savings, for instance, reducing fuel consumption.

Metal powder contributes to the sustainability work

”Metal powder has a number of interesting environmental applications. It is able to absorb contaminants and heavy metals from soil and water, and it can reduce corrosion and extend the life of components. Metal powder is green technology, and the products  Cleanit® LC and Cleanit® EC has the potential to revolutionize water treatment”, says Ulrika Rask-Lindholm, Vice President Communications of Höganäs AB.

”Cleanit® LC is an innovative technology based on a specially designed iron powder, which provides reliable and energy-efficient water treatment. It is capable of removing multiple contaminants from groundwater and drinking water, including hexavalent chromium, arsenic, selenium, phosphates, and radioactive isotopes. Unfortunately, such substances are present in the drinking water in many places. Sometimes, the contaminants occur naturally in the groundwater, sometimes they are the result of human activities. Regardless of how they got there, they are a health issue”, Ulrika says.

Highly absorbent iron particles

hoganas2Cleanit® LC consists of highly porous iron particles combined with proprietary functional components. No hazardous byproducts are produced or released during the process and no chemical additives are needed. The medium can easily be regenerated by a weak acid wash or other processes. Medium life is typically greater than one year, but once it has been spent, it can be returned back to Höganäs for recycling, or disposed in a non-hazardous landfill.

”Cleanit® LC contains a high-purity iron powder with high internal porosity, and the particles have a very large reactive surface area. This is why the operating capacity is so high”, Ulrika Rask-Lindholm says.

”The treatment system consists of vertical columns where the absorbent medium is packed. Water is fed from the bottom, and the contact time depends on the contaminant type, concentration, and other water characteristics. Part of our concept is to make it easy for our customers to install the solution. Höganäs offers a zero-cost and zero-obligation pilot test, where we deliver and run a test module to allow the customers to evaluate the performance of the system on their own water. In a second phase, a complete unit is installed, and we provide various kinds of support for the process”.

”We have also developed a technology for industrial wastewater treatment. It uses electrocoagulation principles, and we call it Cleanit® EC. Specially engineered electrodes remove the contaminants from the water, and the functional units of the electrodes are highly porous metal particles. The technology makes the electrodes customizable, and they can be designed for the site specific contaminants. The system consumes significantly less energy than the alternatives. It can handle heavy metals, organic substances, ammonia, nitrates, phosphates and various other contaminants which are found in industrial wastewater”, Ulrika Rask-Lindholm says.

The article was published in June 2016.