Herein the staff members of Ekoström Recycling present a unique innovative solution for efficient and profitable converting of dirty PET bottles from disposal fields and municipal collecting systems into clean flakes suitable for further processing into valuable products.

In the following sections you will find useful information about the concept of mini-plant and what we mean by “plug’n’play”, how to make profit by using of this equipment etc.

PET bottle recycling plant
Capacity: approx. 250 kg/h

Business solution

An average company operating the medium size disposal field for home wastes may collect up to 100 tons of used PET bottles a month. This amount is sufficient for the full-time running of mini-plant, but definitely is not enough for the medium and higher capacity industrial scale equipment. Consequently the collected bottles either should be recycled at sight or moved from the disposal field to the production facility which is often remote by substantial distance (sometimes hundreds of kilometers). This brings to essential rising of overheads associated with baling, increasing transport costs, intermediate warehousing and additional handling, loading and off-loading works. Furthermore, it is an important aspect of “disposal field bottles” transportation involved, i.e. extremely heavy contaminated, often badly sorted material (we had an experience of finding bricks, rust irons, steel gas cylinders and other heavy objects in the bales prepared for transportation) and hence up to 30 per cent of the mass is just a loss at converting it into flakes.

Based on these facts you may make your own conclusion, finding that it is much more efficiently do not transport baled bottles collected on disposal fields, but having relatively high purity and bulk density clean PET flakes. Thereby PET recycling profitability is essentially growing.

It was also revealed that the size of initial investments often plays the significant role at decision making for purchasing of new recycling equipment. It was found that a professional PET bottle recycling plant is very attractive for the small and medium companies which like to develop their business from scratch but are not prepared to invest high amounts at start up.

Considering all these aspects the concept of a compact mobile “plug’n’play” mini-plant for the flexible operation was developed by Ekoström Recycling. This mini-plant is specially designed to be used by a wide range of PET bottle recyclers worldwide: disposal field owners, municipal or private waste collecting and sorting stations, plastics processing workshops, bottlers etc.

Plug and play

The entire plant is assembled inside a 20’ freight container. All machinery, piping and wiring are ready made. The plant is fully tested with material in our workshop in Sweden prior to dispatch, to ensure that everything works satisfactory.

When the mini-plant reaches its destination area and the container is unloaded from the trailer to the ground, you are only a couple of hours from starting production. Open the two doors of the container and connect the outlet cyclone to its pipe with provided quick couplings. Put your big bags/ boxes under each outlet to collect the final product. Under each outlet for waste you put additional skips.

Finally you connect the water supply hose, sewerage hose and power supply cable to their sockets on the side of the container.

Now the plant is ready for operation, it’s as easy as plug and play.

Economical aspects

Over the last years the price for virgin PET has been soaring. The economical key figures of PET bottle recycling, gives better performance and makes business financial results outstanding both in absolute revenue and in pay-off period.

As soon as your business grows you may increase the park of your mini-plants expanding your recycling ability over new territories. Having several mini-plants in operation has another substantial advantage. Compare to a high-capacity plant you may run your technological process practically without any interruptions. For example while one of your mini-plants is on maintenance or service and repair works other plants continue production making your business process more regular.

The market price of PET flakes depends on their overall quality, as defined by purity, color and size. This is a result of many factors, such as collecting system, pre-handling, sorting and finally processing in the recycling plant. Depending on your local conditions, i.e. costs for labor wages, electricity and fresh water tariffs, waste disposal, used bottles and the market for the end product, you will need some time until you have found the best choice to maximize your profit. Now we come to the subjects of further processing of recycled flakes and possible applications which makes your business profitable and prospective both for you and for the buyers of your product.

Final product quality

PET flakes obtained in this mini-plant are clean enough to be recycled into pellets for further processing by extrusion, injection molding or fiber manufacturing into a wide range of final products.

It is generally recommended to convert flakes into pellets due to clean flakes on macro-level, never are pure enough on micro-level. With the p elletizing process, purification by means of degassing volatiles (mainly acetaldehyde) and micro-contamination melt filtering conduce to material with high degree of purity.

It also slightly increases and stabilizes intrinsic viscosity of polymer and equalizes properties of different material portions. Furthermore pellets have regular bulk density and particle overall dimensions which is ideal for plastic processing technology.

Limitations

Although the mini plant is capable of recycling many kinds of plastics its main usage is PET bottle recycling. It is important to mention that the plant can not recycle everything. Therefore it is necessary to presort the plastic before feeding the plant. Some limitations of the plant are listed below:

Colour . If green, blue, brown and transparent PET bottles are processed together, you will get a mixed end product. All flakes will be PET but since it is mixed with different colors it is not possible to reuse for transparent reprocessing.
PVC . Sometimes bottles are made from PVC (mainly for vegetable oil), sometimes used inside caps for sealing to the bottle thread etc. It looks quite similar to PET but this material is extremely harmful for further processing since PVC acts destructive in thermal processes of PET recycling. To separate PVC from PET you need an additional detector.
Metal . Will damage the knives of the chopper and may even cause breakage of rotor. If small pieces continue further in the process they will end up in your end product. Metal pieces that are mixed with PET will lead to major damages to extruders, with very high costs for repair or even replacement of extrusion elements.
Glue . Ordinary water soluble glue will be removed but there exist a number of different types of glue on the market that are more difficult to remove. Hot melt glue will not dissolve in water and needs additional treatment. If glue will remain on the PET flakes it will influence the color of the plastic in further processing.

It is important to mention that stated above limitations can be solved by implementing the appropriate technology in your process or choosing the right application of recycled PET which increases your sales price and minimize production costs.