Hold Cleaning Materials and Chemicals
Planning and using hold cleaning stores: alkaline and acidic cleaners, application methods, crew safety, and the residue and MARPOL constraints on what goes over the side.
Hold cleaning stores are a planning problem before they are a chemical one, because the materials must be aboard and the time available before the ship reaches the load port. Cleaning between cargoes is usually done on passage, and a ship that arrives without the stores or without the weather to have used them has few options at the berth.
The full article will cover the main product classes and what each is for: alkaline degreasers for oily and organic residues, acidic cleaners for scale and certain mineral residues, and specialised products for particular previous cargoes. It will cover application by spraying, soaking and mechanical assistance, dilution and contact time, and the sequence of rinsing that follows.
It will also cover the two constraints that bound the choice. Crew safety governs handling, protective equipment and enclosed space work during cleaning. And MARPOL Annex V, read with the harmful to the marine environment status of the residues being removed, governs whether the washings may be discharged at sea at all or must be retained for a reception facility.