Background
Salt Separation Services has supported a leading luxury passenger cruise line since 2012, having designed and installed multiple seawater Reverse Osmosis (SWRO) plants across its fleet. Each vessel in this class is fitted with three high-capacity 800 m³/d 2-pass SWRO units, responsible for producing both potable and technical water on board.
As a company committed to sustainability, this cruise operator was an ideal candidate to trial our new antiscalant solution: SpectraGuard111 (SG111). SG111 is a highly concentrated, phosphate-free antiscalant developed specifically for seawater reverse osmosis systems.
Thanks to its 11x concentration, it allows operators to significantly reduce chemical usage, storage space and packaging waste. In addition, SG111 drastically reduces shipping requirements: fewer drums are needed, meaning fewer deliveries, less freight volume and lower overall transportation emissions. This translates into reduced logistical effort for the crew and contributes to a lower carbon footprint, aligning closely with the cruise line’s sustainability goals.
Reducing Chemical Volume at Scale
Theoretically, each 800 m³/d 2-Pass SWRO plant should use around 52 drums of traditional 25kg antiscalant per year. With 15 plants operating across the cruise line’s fleet, this amounted to approximately 780 drums annually.
Using typical seawater chemistry and in-house projection tools, we determined that switching to SG111 could reduce this total to just 45 drums per year – a 94% reduction in chemical volume.
In practical terms, this means each plant now only requires 3 drums of SG111 annually, compared to 52 drums of traditional antiscalant. This efficiency is due to SG111’s higher concentration:
1 drum of SG111 lasts 19 weeks.
1 drum of traditional antiscalant lasts just over 1 week.
SG111 also offers a longer shelf life of 2 years, double that of traditional antiscalants (1 year), providing additional flexibility for storage and procurement.
From a cost perspective, the annual estimated product spend per plant is now slightly lower:
- Traditional antiscalant: £6,812 per plant/year
- SG111: £6,555 per plant/year
Fleet-wide, the estimated cost difference becomes more significant:
- Traditional antiscalant: £102,180 per year
- SG111: £98,325 per year
This switch not only reduces chemical volume and associated packaging waste, but also brings shipping cost savings thanks to fewer deliveries and reduced freight volume and weight, making SG111 the more sustainable and cost-effective solution.
Smarter Chemistry, Cleaner Oceans
Following a successful trial on one vessel in 2023, the cruise line has since adopted SG111 across two of its five vessels. This transition has already reduced their total annual antiscalant use by over 37% – from approximately 780 drums to around 486 drums – with further reductions expected as more vessels convert.
This change has delivered substantial operational and environmental benefits for the customer, including:
- Lower overall chemical consumption
- Cost savings
- Lower storage and handling requirements
- Reduced packaging waste
- Decreased shipping and logistics costs
- Extended chemical shelf life
- Environmental impact reduction
From an environmental perspective, the shift to SG111 means fewer plastic drums manufactured, transported and disposed of, resulting in a direct reduction in plastic waste, emissions from shipping and handling related energy use. Additionally, as SG111 is phosphate-free, it helps protect marine ecosystems from nutrient pollution, supporting the cruise line’s broader sustainability goals.
A Sustainable Step Forward in Seawater Desalination
By switching to SG111, this customer has successfully maintained SWRO system performance while advancing its sustainability objectives.
With significantly reduced chemical volume, packaging and logistics needs, SG111 represents a smarter more sustainable antiscalant solution for large-scale marine desalination systems.
To learn more about SG111 and its full benefits, read our product spotlight article here or contact our team at sss@saltsep.co.uk.
