Tallinn University of Technology

After disposal, the product becomes a waste and its fate depends on whether or not it has a reasonable and profitable application. Unfortunately, packaging products are often made from different types of materials which are difficult to separate from one another, says Andres Krumme, a professor at Tallinn University of Technology.

There is a lot of packaging among the materials being disposed of, so it is up to the consumer to make wise decisions

The article was published on the Estonian news portal Novaator.*

Waste that does not have any application, such as some mineral waste, mixed waste and construction waste, is landfilled. In terms of material circulation, this is the worst option, says Andres Krumme.

The next option is energy recovery, i.e. incineration to produce energy. Low-value, special types and dirty organic waste are suitable for this purpose. Energy recovery is better because you do not have to extract new fossil resources to get that amount of energy. However, the bad thing is that the life of these materials ends there.

Thus, recycling is preferred where possible, giving the waste a new life as a material. In order for recycling to be economically viable, the waste must be sorted by type and relatively clean or easy to clean, otherwise it falls into the category of landfilling or incineration.

A separate category is composting, where biodegradable materials and food waste end up.

Problems with packaging

Probably the most common material to be disposed of is packaging, and in terms of environmental friendliness it is worth focusing on this area. Packaging generally has two purposes — to protect the product being packaged and to provide information to the consumer, i.e. to make the product attractive to the buyer. The performance of these functions has led to the practice of combining various materials. A separate question is whether this activity is always sustainable.

As waste problems have worsened, the design of packaging has become more important, with the third important goal in mind – to recycle packaging at the end of its useful life. To this end, packaging should use the least amount of different materials, which should also be easily separable, thus allowing plastic, paperboard/cardboard, metal and glass to be sorted separately.

How to make environmentally friendly choices?

Thus, an environmentally friendly consumer can, above all, give preference to packaging designed for recycling and avoid products with mediocre contents which are marketed in luscious packaging that is not actually necessary to protect the product. This way of thinking is important, as packaging made of inseparable components is currently the biggest problem in terms of recycling.

Existing technology does not allow efficient and profitable mechanical separation of packages consisting of layers of different materials tightly fused or joined together, such as juice packs, where the cardboard layer is placed between the plastic layers. Energy recovery is currently the best solution for such packaging waste.

Chemical recycling technologies, in which such complex wastes are decomposed into parent compounds from which new materials can be synthesised, are still in the development phase. In addition, an environmentally friendly consumer should prefer carbon-neutral, bio-based packaging or packaging made from recycled material. However, these are still not widely available.

For many other products, it is worth taking them to a waste collection station at the end of use, where specialists advise on sorting and from where the waste usually goes to handlers who can recycle it in the best possible way available.

Finally, it is worth mentioning that energy recovery should not be performed at home. Few waste burns safely in domestic heating stoves without producing toxic by-products. Waste suitable for energy recovery must be unfinished, such as dry wood, paper and cardboard. Plastic products with a burning match mark are also suitable, but it is generally advised to avoid burning plastic and other organic waste at home.

*As of October, the researchers of Tallinn University of Technology answer the questions of readers of the ERR science news portal Novaator on topics that require clarification or are of current interest.