Lindner rolls out improvements for 'bottle-to-bottle' recycling

Friedrichshafen, Germany — When Lindner Washtech GmbH packed up the crates and took down the signs after the K Show in 2019, the recycling equipment maker absolutely knew it was time for change.

Spurred by customer demand voiced at the trade show held every three years, the Grossbottwar, Germany-based subsidiary of Lindner Recyclingtech GmbH went back to the drawing board with its hot-wash system.

And now, the company is showing off the new tower approach at Fakuma just about two years later.

Hot-wash systems are used in conjunction with cold-wash systems when the quality of recycled plastic has to increase to reach food- and bottle-grade standards, said Marcel Willberg, sales manager for Lindner Washtech.

Cold wash can get plastic most of the way there, but adding a hot-wash system into a Lindner recycling line can increase production quality that incremental step needed for food-grade applications, he explained.

"With the hot-wash system, let's say we improve the quality level the last 1 to 2 percent. So this is really that this goes in high-grade applications: food-grade applications, bottle to bottle," he said.

Hot-wash systems help in the final removal of materials such as glue, ink and paper fiber as well as odor to allow the recycled resin to be used when stronger standards need to be met, Willberg explained.

Creating a cleaner resin also allows the material to be used in other nonfood-grade but higher-end consumer product packaging. Consumers are increasingly asking for higher recycled content in their containers, and brand owners are responding by asking for more and cleaner streams of recycled resin.

This trend, Willberg said, is creating demand for more Lindner machinery as companies work toward achieving sustainability goals they have established, often using 2025 or 2030 as target dates.

"They want to promote recycled material, bottles from 100 percent [recycled resin] because the customers, the final users, are asking for it," he said. These consumers are increasingly willing to spend extra money for products using 100 percent recycled plastic in the packaging.

Lindner's new hot-wash system stacks two "cubes" or tanks that use a combination of water heated to 70-80° C (158-176° F) and friction to provide the extra cleaning. Each cube commonly washes for 5-8 minutes and the material goes through each cube. The process also can include a caustic solution to aid in the cleaning. A closed-loop system keeps water from the hot-wash system separate from the cold wash.

While Lindner is only now officially introducing the hot-wash system to customers on a broad scale at Fakuma, the firm actually has already sold four units, Willberg said.

"We saw the market. There is a demand for higher-quality applications," Willberg said. "After the K show, more and more customers asked for hot-wash systems. This is the reason why we invested engineering capacity in this field, especially for the hot-wash system."

The company's new tower approach also allows for different types of plastics, including different films and rigids, to be processed. The company's previous approach could not handle PET effectively due to density that caused the material to sink to the bottom of the equipment, Willberg said.

Higher virgin resin prices also have been helping demand for Lindner recycling equipment, he explained.

That's because recycled resin pricing moves, to a large extent, in concert with virgin pricing. And these higher prices are allowing processors to invest more in new equipment to handle increasing demand, Willberg said.