Used Materials Spare Resources

Zech Umwelt GmbH has developed a new, innovative purification process for contaminated plastics. By means of an intensive cold wash, this fully separates HDPE plastics from clinging residues.

They are short-lived, but are needed everywhere: plastic packagings. In domestic households the recycling of yoghurt pots etc. has become an everyday thing in Germany. But what about packagings that are "contaminated" with persistent residues? 

Zech Umwelt GmbH has a great deal of competence in the fields of soil, water and air pollution, as well as in the management of materials flow. Creating new possibilities via solutions that are both ecological and economical – that is the motto of the company, which happens to have the most dense network of soil-purification plant in Germany. Even in an economically challenging environment, Zech Umwelt GmbH continues to grow.

A self-developed, innovative treatment procedure now permits almost 100 percent material recycling of such contaminated external packagings as cans or canisters made of HDPE plastics. These packagings were previously subjected to thermal disposal processes. The company's aim was to spare resources and to make use of the flow of waste materials for the manufacturing of new products. The resulting grist is used to make similar products and other tools. The process is able to treat a wide spectrum of contamination in keeping with AVV 150-110, ranging from oils, acids and bases to industrial cleaners and enzymes.

After visual inspection and assignment of the emptied receptacles to the new plant in Gladbeck, North Rhine-Westphalia, all metallic parts are first removed. A preliminary fragmentation and mechanical cleansing procedure next removes the last product residues. The heart of the process is the subsequent wet grinding with multistage, intensive cold washes. This is concluded using water alone, without any wash additives such as surfactants. In comparison to other existing procedures, this option is characterized by reduced environmental pollution, less energy consumption and lower costs. After a final drying, the end result is a high-quality grist.

Regular checks made at various process control points help to ensure the quality required for subsequent further processing. The grist is produced with a size of less than ten millimetres and a residual humidity of less than two percent. It is made available in so-called big-bags.