IMC solves The O2's food waste disposal problems

The Challenge

When Karen Cmela joined as Head of Support Services of AEG Europe, owners of The O2 (or Millenium Dome as it used to be known), she embarked on a series of initiatives that would fulfil AEG's objective of maximizing the diversion of its waste from landfill. Whilst the Green Agenda was high on AEG's list of priorities, the commercial necessity to reduce costs was even more important. Dry recyclable waste products such as tins, cans, glass, plastics, cardboard and paper were all relatively straightforward to dispose of. Food waste, on the other hand, was, no pun intended, a completely different kettle of fish and provided Karen with a much more difficult problem to solve.


With an annual programme of around 200 shows and events, The O2's 20 food concession units are regularly operating at full capacity and generate substantial volumes of food waste. With a further 96 Arena suites providing food and beverage hospitality and 25 restaurants serving the highly popular Entertainment District, The O2 generates up to 30 tonnes of food waste each month. The process of bagging, binning and sending its food waste to landfill was costing The O2 in the region of �35,000 per year.


Faced with a diverse range of potential food waste recycling solutions, Karen and the AEG team focussed on finding a solution that would not only fulfil all of The O2's and its subcontracted services companies' requirements but would also garner the restaurants', and their corporate owners', full support and participation. Of particular importance, the chosen solution should be unaffected by rising and uncertain waste disposal costs, extremely cost efficient and ideally provide AEG with the ability to take complete management control. On site composting was deemed the only solution that could satisfy their multitude of requirements.

The Solution

Karen's initial step was to instal the largest available "Big Hanna" In Vessel Composter (IVC) which had capacity to recycle around half of the food waste that the Arena concessions were generating. Whilst the IVC was able to convert all of the food waste, including meat products, into compost, the wet nature of the waste suppressed its capacity to generate the temperatures required to satisfy ABPR regulations as well as producing an unpleasant odour. However, with the subsequent introduction of waste macerating and dewatering equipment, manufactured by IMC, Europe's leading producer of commercial food waste disposers, the IVC's capacity was effectively increased five-fold so that all of the Arena's, and around one third of the Entertainment District's, food waste could now be recycled into high quality compost.

How it Works

This system has proved both effective and efficient and has quickly won the approval of big name restaurant brands on site including Frankie & Benny's, Nando's, Pizza Express and haha. Each restaurant and concession is supplied with an 80 litre bin in which to dispose of its food waste. Bins are collected once or twice a day and the contents checked for non-food items on a waste sorting table prior to emptying into an IMC Food Waste Macerator. The macerated waste is then automatically passed through an IMC "WastePro" Dewaterer which extracts the solid particles and allows the residual grey water to be dispensed to drain. With mixed catering waste typically comprising of around 77% liquid, this process reduces the amount of waste requiring further treatment by up to 80%. The solid fraction is captured in small, lidded bins and mixed with a small quantity of carbon enriching compressed sawdust pellets before being loaded into the IVC. Waste is fed into the IVC at least once a day and, after 6 to 8 weeks in vessel, emerges as compost which is then allowed to mature and improve still further before being used in the site's numerous plant displays. "The system of collecting waste from each of the catering outlets has proved relatively straightforward to implement," says Karen. "We provide a round-the-clock service including two shifts and operate the macerating and dewatering equipment, which has been supplied as part of a fully made-up waste sorting table, for several hours each day. We collect the waste from the restaurants typically once a day but, when there is an event on in the Arena, waste is uplifted from the concessions on a more frequent basis. We wash out the bins first before redistributing them, a task which our contract cleaners, Cleanevent, have been happy to embrace as their life is now made so much easier."

Universal Approval

The system has been well received by the catering establishments who have been keen to embrace The O2's green approach and have seen their waste disposal costs tumble dramatically. The Manager at Rodizio Rico for example has nothing but praise for the initiative: "Our waste collection bills have reduced significantly since the introduction of the food waste recycling system. By focusing more on what we're throwing away we've been been able to identify where we've been needlessly wasting food stuffs in the past or over-ordering. Other than instilling on staff the discipline of ensuring any food waste is placed in the dedicated bins supplied to us, it has been a piece of cake to implement. It has also enabled us to better control the disposal of our dry recyclables which, because they are now uncontaminated by any food waste, can also be reprocessed. At our monthly tenants' meeting we are able to share our experience and discuss with AEG any improvements that might be made. It's normally a very short meeting as generally we are all very happy with the system."

Return on Investment

AEG anticipated a pay-back on the equipment of just 18 months. "We are on track to beat this," said Karen, "helped in the main by the adoption of the pre-treatment equipment which, on its own, would have paid for itself in only 3 months. If there was one thing that we might have done differently, it would be to specify and, if possible, design in all of the equipment from the start. The pre-treatment equipment resolved all of the teething issues that we had with the IVC." By breaking down the waste particles into a consistent size and greatly reducing the water content, the macerator and dewaterer have enabled the composting process to achieve the required temperature of over 60 degrees C for a minimum period of 4 days thereby complying with current ABPR legislation. It has also had a direct, positive impact on the quality of the compost, test samples of which have been found to exceed the stringent standards required to achieve BSI PAS100 status.

PR Value

The Head of Corporate & Social Responsibility at The O2 is especially proud of their food waste recycling initiative. "We make a point of communicating to the visiting public via our Arenamation monitor display system that 100% of our food waste is recycled. Our success has also endeared us to local residents who take an active interest particularly in our recycling initiatives." The O2 Arena has recently won a Tourism Award where its positive approach to sustainability was highlighted for particular praise. Karen points out: "We have hosted a number of visits to site by other organizations facing similar issues and the LDA has been very impressed with what we have been able to achieve."

Olympic Proportions

Another visitor to site, the Organising Committee for the 2012 London Olympics & Paralympics, must have been impressed, too, as Karen joins them in her new role as Senior Manager of Cleaning & Waste Management! "I think the first thing my successor at The O2 will do is to introduce a second In Vessel Composter in order that the remaining two thirds of the Entertainment District's food waste can also be recycled. As for my new role, I won't have to take so long to track down the best solution!"


The O2 is one of the world's premier stadia with a reputation for delivering the very best visitor experience

Wet food waste is brought to the recycling area in 240 litre wheelie bins which are emptied onto the sorting table using an automated bin lift.

Any foreign objects are manually removed from the waste bin contents. The clean food waste is then scraped along the table into the macerator's hopper.

The macerated food waste passes from the Food Waste Disposer into the WastePro Dewaterer where the solid fraction is retained whilst the grey water automatically dispenses to drain.

The O2's In Vessel Composter can process up to 1200 kg of food waste per week

The food waste recycling equipment occupies minimal space and is straightforward to operate and maintain.

The food waste recycling equipment is housed in a covered area located amongst The O2's other waste processing facilities.