CIRCULAR ECONOMY IN THE PLASTIC PACKAGING INDUSTRY

Never before have the topics of "circular economy", "recyclable materials cycle", "climate protection", "sustainability" as well as "acting in a resource-saving manner" been so much in the focus of environmental and socio-political interest as they are today. For years, national and international legislation has been trying to promote the responsible use of resources, the protection of people and the environment as well as the recycling of waste with central specifications and measures.

Nevertheless, there are still largely linear value chains in the plastics industry in the area of plastic packaging, which do not guarantee the reuse of the plastic material as a valuable material at their end. Thus, plastic waste is often only thermally recycled, i.e. burned to generate electricity or district heating, or illegally sold via detours to developing countries in Africa or Asia, where it then usually ends up in the environment or the oceans. Unfortunately, recycling still takes place far too rarely.

There are several reasons for this. On the one hand, the research and development of sorting and recycling plants was neglected for many years against the backdrop of cheap virgin materials and a lack of economic efficiency. Furthermore, the use of recycled plastics in packaging is not legally permitted for certain areas of application. Due to the regulations EC 1935/2004 as well as EC 10/2011, most mechanically processed plastic waste made of polypropylene (PP), polyethylene (PE) as well as polystyrene (PS) may not be used for primary packaging in the food and pharmaceutical sector. In the cosmetics packaging sector, too, recycled plastics may only be used under certain conditions.

Circular economy Plastic packaging at H&K Müller

Solar system on the roof of H&K Müller GmbH & Co. KG

Plastic injection moulding Circular economy

Injection moulding machine on which material from circular economy processes is processed

Circular economy for plastics - what is it?

The circular economy for plastics is a concept that aims to extend the life cycle of plastics and reduce their environmental impact by keeping them in a closed loop. This means that plastic products are not simply disposed of after use, but are reused, recycled and reprocessed in a continuous process.

The circular economy for plastics involves several steps and principles:

Design for recycling: when developing new plastic products, care is taken at the design stage to ensure that they are easy to recycle. This may include selecting recyclable materials, avoiding combinations of materials or designing components with easily separable joints.

Collection and sorting: Used plastic products are collected and sorted by plastic type or colour. Separation of plastics is important because different types of plastics require different recycling processes.

Mechanical recycling: In this process, the collected plastics are shredded, cleaned and processed into plastic granulate that can be used as raw material for the production of new plastic products.

Chemical recycling: In this process, the plastics are broken down at the molecular level and converted into their starting materials or into valuable chemical compounds. This leads to a better quality of the recycled material and opens up the possibility of reusing plastics several times in a high-quality way.

Energy recovery: Plastics that cannot be recycled mechanically or chemically can be incinerated in special plants for energy recovery, generating heat and energy.

Avoiding single-use plastics: An important aspect of the circular economy for plastics is reducing the use of single-use plastic products in favour of reusable alternatives.

Awareness raising and consumer education: Consumers are informed about the importance of plastic recycling and proper disposal to raise awareness of the environmental impact of plastics.

The goal of the circular economy for plastics is to reduce the amount of plastic waste, minimise environmental impact, reduce dependence on fossil raw materials and promote the sustainable use of plastics. This requires industry, governments, consumers and other stakeholders to work together to ensure effective implementation of this concept.

Circular economy in the plastic packaging industry using the example of the sustainable injection moulded packaging manufacturer H&K Müller from Engelskirchen.

Renewable plastics and energy - sustainable processing - long service life - recycling - reprocessing

Classical plastic is based on waste or by-products of petroleum refining. Like all fossil resources, the starting products of plastics production are therefore only available in finite quantities. At the same time, against the backdrop of rapidly advancing climate change, a massive reduction of CO₂ emissions of fossil origin is necessary. There is a need for responsible handling of plastics as a valuable material. Without plastics, for example, it would not be possible to guarantee the food supply we are accustomed to today or the established high medical standards in our society.

Contrary to what is often assumed, the use of alternative materials such as sheet metal, glass or coated paper composite packaging is not an alternative to plastic. On the one hand, in contrast to plastic, they cause many times higher CO₂ emissions during processing and, due to their higher weight, also during transport. On the other hand, coated or lacquered paper composite packaging can only be thermally recycled, which means that valuable resources, some of which are only available to a limited extent, are lost.

In order to be able to achieve politically set climate protection and sustainability goals, a resource-conserving recycling economy is needed that increasingly relies on secondary raw materials. It is therefore imperative that packaging and products made of plastic are developed for recycling as easily as possible.

Container with recycled plastic granulate from the circular economy process in the materials warehouse of H&K Müller GmbH & Co. KG

What are the challenges of the plastics industry in relation to the circular economy?

The plastics industry faces several challenges in implementing the circular economy that may affect the sustainable use of plastics. Some of the main issues are listed below:

Plastic diversity: there are a variety of plastic types with different properties. The diversity of plastics often makes recycling difficult, as different types of plastics cannot always be mixed well together or recycled.

Quality loss during recycling: Plastics can lose quality in any recycling process. This loss of quality can affect the properties of the recycled material and limit its possible applications

Contamination and pollution: Contaminants such as labels, dyes or other materials can interfere with the recycling process and reduce the quality of the recycled material.

Required collection and sorting: Efficient collection and sorting procedures are required to separate plastic waste by plastic type. The availability of such systems may vary from region to region.

Economic factors: Sometimes recycling plastics can be more expensive than using new plastics from crude oil. This can affect the economic viability of recycling.

Limited recycling capacities: Existing recycling facilities may have limited capacity to process the growing amount of plastic waste.

Challenges from mixed plastics: Mixed plastic waste or complexly compounded products are more difficult to separate and recycle.

Short lifespan of plastic products: Some plastic products have a short life span, which means they are disposed of more quickly and there is less time for recycling.

Lack of infrastructure: There is often a lack of uniform standards for recycling plastics, which makes communication and exchange of recycled material between different actors difficult.

Cultural habits and consumer behaviour: A change in consumer habits, use of single-use plastic products and proper disposal is needed to support the circular economy for plastics.

Lack of standardisation: There is often a lack of uniform standards for recycling plastics, which makes communication and exchange of recycled material between different actors difficult.

Despite these challenges, there are efforts by industry, governments and organisations worldwide to advance the circular economy for plastics. Technological innovations, improved recycling processes and legislative measures are underway to improve the sustainability of the plastics industry.

What are the possibilities for recycling plastic waste within the framework of a circular economy?

The mechanical reprocessing

In this method, the plastic waste is sorted by plastic type in sorting plants, shredded and impurities are "mechanically" removed in multi-stage washing and cleaning processes. In order to be able to achieve constant process parameters during reprocessing, the cleaned plastic waste is then regranulated into granulate. During mechanical recycling, the basic polymer structure of the plastic remains almost unchanged.

The chemical reprocessing

In the chemical reprocessing of plastic waste, the polymer chains of the plastic waste are broken down by adding pressure and heat in a complex and energy-intensive process. The plastic waste is converted back into its monomeric building blocks. The result of this process, also called thermal pyrolysis, is crude tall oil. This forms the starting material for refining new plastic material. In this process, new polymer chains are built up within a synthesis process.

Measures to increase the reuse rate of plastic waste

WHAT CONTRIBUTION CAN MANUFACTURERS AND DISTRIBUTORS OF PLASTIC PACKAGING MAKE?

Circular economy for plastic packaging — How does the circular economy work in the plastics industry? What can manufacturers of plastic packaging do for a closed-loop recycling system?

Material-saving design: Only the absolutely necessary amount of plastic should be used for the production of a packaging, as required by the respective application.

Use of light colours: By avoiding colouring or producing packaging with light colours, light-coloured packaging can be produced again after the packaging waste has been recycled. The more often plastics are mechanically recycled, the darker the shades will be when reprocessed.

Standardised material types: By focusing on a few types of plastics in the packaging industry, the sorting effort for material recycling can be reduced.

Dispensing with colouring: By dispensing with colour additions, recycled plastics can be used to produce light-coloured packaging again.

Use of IR masterbatches: Where the product to be packaged requires dark colouring of the packaging, e.g. with UV-sensitive media, so-called IR masterbatches must be used. These enable modern sorting systems to recognise dark-coloured plastic waste.

Avoidance of composite materials: : Instead of composite material packaging, such as wraparound cardboard packaging or in-mould label packaging, pure packaging solutions should be used to enable material recycling. Composite material packaging can usually only be thermally recycled.

Use of renewable raw materials: By using renewable raw materials, such as tall oil from forestry waste, no further CO₂ emissions from fossil sources are introduced into the circular economy.

H&K Müller's commitment to a sustainable circular economy

H&K Müller, as a sustainably oriented manufacturer of plastic cans, plastic packaging, dosing aids and plastic injection moulded parts, has been processing recycled plastic waste for over 60 years. This comes from our own production waste, sprues and start-up goods. In addition, H&K Müller has been working for many years with well-known manufacturers of biologically based and recycled post-consumer recyclates. Thanks to intensive research and development work with our partners, H&K Müller is able to produce almost the entire standard range from plastics of biological origin and, where the current legal situation permits, from mechanically reprocessed recyclates.

H&K Müller is one of the few packaging manufacturers in Germany to be certified according to ISCC Plus (International Sustainability & Carbon Certification) and is therefore authorised to process sustainable ISCC Plus certified plastics of biological origin.

During the construction of the new production site in 2009, the topics of energy efficiency, resource conservation and environmental compatibility were a particular focus. With a photovoltaic system with an output of 420 kWp on roof surfaces, H&K Müller generates around 17 % of its energy requirements itself. A sophisticated cooling system is used for cooling and air-conditioning of machines, plants and production halls, which is supplied by deep wells and free coolers. A clever structural arrangement of individual parts of the building makes it possible to dispense with an energy-intensive pneumatic conveyor system for plastic granulates.

More than 97 % of the plastic packaging and injection moulded parts produced by H&K Müller are pure, i.e. consist of one type of plastic (PE, PP, PS, ABS). In the remaining proportion, two different types of plastic are merely mechanically joined together and not glued or welded. This enables easy material separation by the end user or in recycling plants.

H&K Müller offers its customers the option of individual finishing and decoration by means of screen printing or embossing. The applied screen printing inks and embossing foils are environmentally friendly and, unlike labels or inmould labels, do not hinder mechanical recycling.

The central location of H&K Müller's plastic injection moulding plant in Engelskirchen in the Oberberg region, with direct access to the A4 motorway, enables us to serve customers throughout Germany quickly and with short delivery routes.