On Board Overboard Case Study

Sector: Marine and offshore
Equipment: Dehydra Bench Food Waste Dewaterer

The backstory

A prestigious German shipbuilder constructs large superyachts, and these luxury liners are frequented by travellers looking for the VIP experience on their next long-haul trip.

Some yachts even boast Michelin-star chefs creating the culinary delights for guests.

The challenge

With up to 30 people aboard the yacht and often cruising within sight of land, this means that the vessels are subject to the stringent worldwide International Convention for the Prevention of Pollution from Ships (MARPOL) regulations that dictate how marine wastes are dealt with.

During the the occasional stopovers, the ship brings onboard as much fresh quality and local produce as possible, to be used when providing elaborate buffets for guests and dignitaries.

But all this fresh food needs preparation, so there are many peelings and cuttings which need disposing of.

When vessels are outside the 12-mile MARPOL limit, in areas defined as ‘special’ – an invisible boundary of regulatory change – they are permitted to discharge food waste overboard, to feed the fish. However, this is on the proviso that the material has been shredded to a sub-25mm particle size. And when they are within the MARPOL territory, this isn’t allowed, so it has to stay on board until the ship arrives at port and the waste can be disposed of properly.

Therefore, the firm needed a MARPOL-compliant solution for processing its food waste, as well as storing it safely on board – without occupying much space or causing a biohazard.

Product image Dehydra bespoke

The solution

The German shipbuilder contacted the Tidy Planet team to request a bespoke version of our Dehydra Dewatering System. They wanted a machine which – when the vessel was in MARPOL boundaries – dewatered the food waste and sent the liquid element and 30% of the weight to the vessel’s on-board Membrane Bioreactor (MBR) sewage system. But, cleverly, when it sailed outside the MARPOL limit, a mechanical switch was initiated to change the flow of the waste and the destination of the finely shredded particles – and instead of being collected and stored, pumped them overboard into the sea.

We therefore recommended a tailored version of our open-format Dehydra Bench Food Waste Dewatering system – which was not only space-efficient, but allowed kitchen crews to easily clean around the unit.

The system also had to be designed to connect with the ship’s safety sensors, ensuring it wouldn’t discharge overboard if the vessel’s limit switches didn’t allow it. Therefore, visual indicators were incorporated to make the settings clear and prevent this from happening.

Having the dewatering equipment aboard the superyacht now enables the unit to reduce its food waste volume by up to 80% – and its weight by 50%. This results in a more densely packed fine particle solid residue, which can be safely put into sealed containers in the boat’s chilled waste room.