Ships, of course, don’t have the facility of garbage collections while they are at sea and will depend upon shore authorities providing this service when they are in port, so what can they do to mitigate the problem? Like shore-side organisations, those aboard ship will try hard to separate and segregate their “recyclables”, but also they will try hard to minimise the waste materials left from their consumable stores, provisions and the like. Well- found ships will also have installed a certain amount of helpful equipment, in the shape of compactors that can be used to squash tins and boxes into a small volume for ease of storage and collection and incinerators that can be used to dispose of anything that can be burned.
There is also much that can be done, in collaboration with those selling stores for ships, to ensure that packaging is not too bulky and can be easily disposed of in the ship’s systems. Minimising the volume of garbage that has to be stored and landed is a useful strategy for reducing costs and contributing to the reduction of wastes in general. Much will also depend on the ports which need to ensure that they have in place adequate reception facilities that ships will find convenient to use. Having to struggle down half a mile of quay to the nearest garbage reception facility is not exactly encouraging for ships’ crews. There are also serious quarantine issues with the landing of ship’s garbage, for instance, with the proper disposal of food waste or wood dunnage and packaging that ports need to deal with.
The amount of garbage produced by a ship depends heavily on the number of people aboard her. While cargo ships have small crews, generating little more than that of a few households ashore, passenger vessels, by contrast, need to have well ordered and often highly sophisticated systems for dealing with ship-generated wastes. In a large cruise ship, hundreds of tons of wastes are generated in addition to the solid wastes and “grey water” produced by the ship sewage and domestic water systems.
Aboard such vessels, the treatment of wastes will be approached on an industrial scale, with specialised equipment sorting, compacting, storing and incinerating all the ship’s garbage, so that what is landed is easily dealt with by mechanical handling systems during the fast turn-round in port. Garbage treatment will occupy a whole department on board ship, and the development of this specialised equipment has gone hand in hand with the design of large cruise ships, with their thousands of passengers.