In intrusion extrusion moulding, low-value plastic waste is converted into new products. Machines shred, heat and press the plastic waste which can then be used to make new products for circular applications. Intrusion is sometimes called injection moulding. This involves injecting hot plastic clay directly from the extruder into the mould. When the mould is completely filled, the clay is then cooled. The resulting clay can be used to make long and complex objects such as the round stakes around young trees to keep them upright. Intrusion is especially useful in making objects with long profiles and poles. The Green Plastic Factory is widening its knowledge and expertise in this technology and is making an even greater impact by saving more plastics from incineration.
For TRANSFORM-CE’s international project, the Municipality of Almere and Cirwinn jointly worked on developing new products for the outdoor space in Almere. The Green Plastic Factory grew from this collaboration. It is a pilot factory where research on IEM technology is done and which processes 150 tonnes of low-value waste from households in Almere every year.
The products that are made from the plastic waste are specifically used for thick-walled objects in outdoor spaces. They are thus heavy, solid products rather than thin, light ones. The Green Plastic Factory uses IEM technology to make products that will last 40 years and are recyclable up to nine times.
What are Green Plastic Factory’s plans? They will continue to further expand their knowledge and expertise in intrusion technology. They need some new machines to do this and these will be installed in the near future. The machines will help make production more efficient.
At present, filling a mould only takes about five minutes but cooling the moulds takes a lot longer at about half an hour. The Green Plastic Factory is experimenting with ways to shorten this time, such as by putting the mould in a cold bath to help it cool down more quickly. Another solution to the time issue is to use several moulds which can be rotated.
One example of what is made at the Green Plastic Factory is tree strakes. Tree strakes are usually made of wood but there are advantages to them being made of recycled mixed plastic. Plastic tree strakes do not rot if they are in wet ground so they last longer. They will also bend rather than splinter so the chance of breakage is minimal. Further, they can be reused and even recycled after use. They are thus a completely circular solution for Almere and are produced locally from local waste streams.
The tree strakes are available in black or grey. Buyers could include other municipalities.
The Green Plastic Factory is continuously working on optimising its processes and assessing the products it could manufacture and how to improve them. For more information see https://www.saveplastics.nl/en/