What’s empty but full of value?

A collaboration in 5 questions

Everyone is familiar with those blue crates of vegetables and fruit in the supermarket. At home we all have at least one or more crates filled with empty beer or soda bottles. But do you have any idea of the value of these crates? The independent store owners of the Retail Partners Colruyt Group each log an average deposit of several thousands of euros every year. When you look at it this way, it’s easy to understand why this stream of returns, and correct crediting, is so important.


Jürgen Sorton is the logistics manager at the Retail Partners Colruyt Group, the company which plays host to other shopping chains such as Spar and Alvo. The group consists of more than 400 stores. The shifts have just changed when we meet Jürgen in his office in the brand new distribution centre in Mechelen. Responsible for facility, the returns centre and frozen goods, he closely followed the construction of the new automatic sorting machine from the very beginning.

1) When did the idea to automate mature?
Jürgen: ‘A few years ago, we devised an action plan to increase the follow up of the return stream of empty crates. Very few logistics companies were paying attention to it, even though there is a lot of money involved. We wanted to maintain the good relationship with our independent shop owners and avoid errors. When Management decided to move from Heist-op-den-Berg to Mechelen, we began to really consider the possibility of automation. Within the Colruyt Group, we already had some experience with the automated sorting of crates, but we didn’t know our efforts would also translate into improved productivity and ergonomic work methods.’

2) What benefits does automation offer you?
Jürgen: ‘Our primary concern was to have more automated monitoring with accurate crediting. Previously, everything happened manually on the truck itself, with a pen and paper. With the automation, we wanted to limit the manual operations so that there would be a minimal chance of human errors occurring. ‘The increased productivity was a welcome extra, as were the improvements to ergonomics. The City of Mechelen requires us to store everything indoors, while in Heist-op-den-Berg we had space outside. As a result, we needed to be creative with the available space and needed to constantly look for ways to optimise the situation. Although we are now working on two building levels, it really helps having a quicker rotation of in- and out-going streams.’

3) How does the installation work?
Jürgen: ‘The sorting line has two entry points. Two operators pick up the crates from roll containers and put them on a conveyor belt. Every roll container has a label that is linked to the digital account for a specific store owner. This account contains all information about the contents and origins of the container. ‘The crates on the belt then go to a vision station. A lateral camera recognises the type of crate. There is a one-on-one check performed with the digital account. A second camera situated above differentiates between full and empty crates. ‘After this passage, we can create a complete account for the store owner and we have all the information needed to sort the crate out and put it on the right belt. ‘We sort the high-runners (blue Euro Pool System (EPS) and Jupiler crates) on the lower level as this increases the efficiency. We bring the remainder to the first floor via a spiral conveyer belt. Then the crates are once again passed through a vision system to adjust their position on the belt. They are now sorted into four different lanes. Crates that are not recognised for one reason or another are sent to the ‘reject’ lane. Even there, the link with the specific store is maintained so that the account is always 100% accurate.’

4) What was your biggest challenge?
Jürgen: ‘There were two. The first was developing accurate one-on-one recognition of the crates, something we promised the store owners. We wanted to be able to work with each other in complete confidence. When we were moving to Mechelen, we already had the installation ready for use, but it had not yet been commissioned definitively. Together with intrion, we spent the first months refining and further adjusting it. It has only been a few weeks since the vision system was linked to the crediting system.’ ‘From the very beginning, we included the independent shop owners in this story. They received a tour of the new site and they understood that the start-up of such a system needs a ramp-up time before being 100 % reliable. ‘The second challenge was healthy productivity. Together with intrion, we performed a feasibility study. At first, we wanted to build two separate lines for EPS and beverage crates. But the volumes were not large enough. A combined installation appeared to be feasible. And that is now 100% operational.’

5) What are the plans for the future?
Jürgen: ‘The current capacity is for 3,000 crates an hour. That will have to be sufficient for the next 15 years. In the meanwhile, together with intrion, we will build a new installation for order picking of potatoes, vegetables and fruit. This installation will soon have to realise a significant improvement in productivity as well.’


“A lot of logistics companies pay too little attention to the return streams, although there are large amounts of money involved. We work together with independent shop owners, because even when it comes to accrediting empty crates, we want to develop a good relationship.”
PrintRetail Partners Colruyt Group NV unites all activities the Colruyt Group has with independents. This relates to approximately 410 stores: half of these are Spar stores, the other half are Alvo, independent Mini Markets and other independent clients. In the autumn of 2014, the company headquarters (Ternat) and distribution centre (Heist-op-den-Berg) moved to a new site in Mechelen.