In a unique project involving ten supply chain partners, global market leader in transportation systems Vanderlande developed two plastic products, that are beneficial for the environment:
- the TUB, a container in which luggage is carried along a conveyor belt at airports
- the TRAY, a crate in which products are stored in automated storage- and distribution centres
The TUB for luggage handling
The TUB is used for transportation of bags and suitcases at airports. The current TUB is made of LDPE that is moulded into shape through rotational moulding. The hollow mould is subsequently filled with PU foam. A scuff rib is attached along the edges.
Partners for Innovation has made a Life Cycle Assessment Quick-scan to measure the impact of the current TUBs. The conclusion is that the weight of the TUB contributes considerably to the energy use of the luggage systems (85% of the total impact). This is due to the continuous transportation of the TUB. Therefore it’s crucial that the TUB cannot be heavier if recyclate is applied. Preferably lighter, to realise a higher energy reduction.
SUEZ has recycled twenty TUBs to research the recyclability of the current TUB. It has succeeded in removing the PU foam from the LDPE edges, making it recyclable. Afterwards Promens used it to produce a new TUB. This went surprisingly well, albeit with a different colour than virgin. According to recycling companies this can be resolved by an improved cleanse of the shredder and compounding the recyclate with a strainer. Furthermore, the UHMPE scuff ribs need to be detachable.
The participants have developed several TUB drafts based on different production techniques. At the moment, Vanderlande is researching which of the preliminary designs is most suitable. Applying the recyclate seems to be possible, and by optimising the design a huge reduction of weight and energy can be achieved.
The TRAY for automated distribution centres
The TRAY is used for the storage of goods in automated storage and distribution systems, also called ACP (Automated Case Picking). This system consists of a stretching structure and an integrated TRAY shuttle; the Vanderlande ADAPTO system. The shuttles transporter the TRAYS with goods to and from the storage and designated entrances and exits. For the current ACP concept no standard storage instruments were available, so Vanderlande decided to develop their own.
Partners for Innovation has made a Life Cycle Assessment Quick-scan to measure the impact of the current TRAYS. The conclusion is that the biggest impact (85%) on the environment comes from the production phase (mainly the material). This means that there benefits can be obtained from the use of recycled material and by optimising the design.
In designing the TRAY much time is spent on determining the specifications for Vanderlande. Most of the time, the TRAYs are piled up in racks containing products. Two things that needed to be taken into account is the heaviest possible load and the highest possible temperature. When a TRAY a product is needed the TRAY is being taken by a shuttle, and made ready for dispatch through various transportation lines and an operator or robot.
During a brainstorm session the specifications were divided in subfunctions. By asking “How can we?” questions we came up with solutions and ideas for each subfunction. In only thirty minutes we had over a hundred ideas. We put all these ideas in a morphological box and combined them to create drafts. Subsequently, we selected a draft which is elaborated on by Schoeller Alllibert.
The potential benefit for the environment of the TUB mainly depends on the weight, its recyclability and the appliance of recycled material. The weight of the current TUB is m/l 16 kg, of which 11.4 LDPE and 4.6 kg PU foam. In the new TUB we use recycled HDPE, when available coming from old, recycled TUBs. A weight of 12 kg seems surely feasable, making 72 tonnes rHDPE applicable. This weight reduction of 25% brings about a energy reduction of m/l 12.5%. Regarding an average size airport with 6,000 TUBs this would translate into an energy reduction of 109,000 kWh/year (392 GJ/year).
The new TRAY is not comparable to the currently used crates. Many functionalities have been added, which make them suitable for automated handling in ACP systems. The potential benefit for the environment of the tray depends on the weight and percentage of recycled PP that can be applied to the amount of trays being produced. The weight of the new tray is 3.6 kg and this can be fully made of recycled PP. In an average size warehouse m/n 100,000 trays are used, this is 360 tonnes rPP. This will increase the demand for recycled PP. Compared to virgin, this will result in an energy reduction of 50%.
Cooperation in the chain
Working together has been inspiring but also difficult at times. In this project, several companies were involved who operate in the same market. This implied that participants needed to be open and frank but needed to respect each other’s intellectual property. Everyone presented their drafts but didn’t have to present their final versions to the group.
Ingeborg Gort firstname.lastname@example.org