Sea Water Desalination Using Reverse Osmosis
Most common watermakers used on yachts and ships use the reverse osmosis system to obtain fresh water from seawater
Regardless the size and range of the system, a watermaker has 3 different stages on his operational:
Seawater filtering
Pressurizing
Reverse osmosis with separation of salt
How does Reverse Osmosis work?
The RO unit separates the salt from water, obtaining a purified fresh water and disposing the impurities with a high concentration of salt.
The ratio between fresh water and the remaining water with high concentration of salt gives a level of the efficiency of the entire process, which improves as the size of the system increases.
The Reverse Osmosis unit consists of one or more membranes contained within “vessels”.
Disinfection of Sea Water by UV light
Fresh water obtained from this process can be further treated, if necessary, with a UV sterilizer that definitively reduces the general bacterial and pathogenic load.
Then an activated carbon filtration is applied to improve its organoleptic characteristics.
The UV sterilizer is extremely effective. The main advantage is that it does not require the addition of chemicals that alter the original taste and flavor of the water.
The advantages of UV filtering include:
- absence of chemicals
- absence of bacterial contamination
- no change of taste
- no elimination of beneficial minerals
The sterilizer guarantees users a bacteria-free water (eliminating up to 95% of them).
Idromar UV sterilizers are definitely to be mentioned among great allies for a safe and healthy environment on board, and nowadays, like never before, we know how important this is at each level.
Products Link
IDROMAR U.V. STERILIZER 2000LT/H Buy Now
IDROMAR U.V. STERILIZER 5000LT/H Buy Now
IDROMAR U.V. STERILIZER 8000LT/H Buy Now
IDROMAR U.V. STERILIZER 10000LT/H Buy Now
IDROMAR U.V. STERILIZER 13000LT/H Buy Now
IDROMAR U.V. STERILIZER 18000LT/H Buy Now
UV sterilizer choice is subject to the capacity needed, the raw water to be treated characteristics and the fresh water quality to be obtained.
Tips for Watermaker Maintenance and Upkeep
For prolonged periods of stop and in any case at the end of the season it is necessary to carry out a special maintenance of the membranes and the winterizing of the system.
This maintenance consists in washing the membranes with 2 different products.
The first wash (Regeneration) is done using the powder CTR which descales the membranes, the second wash (Winterizing) uses the liquid product FLD which sterilizes the membranes.
Products Link
IDROMAR WATERMAKER WINTERIZING KIT Buy Now
Our Idromar watermaker winterizing kit (CTR + FLD) includes Citric Acid to Wash membranes + Liquid for winterizing. Idromar Regeneration Kit to winterizing membranes. The kit has Citric Acid powder to wash membranes and a liquid to winterize them.
Instructions on how to Clean your seawater watermaker
Any watermaker needs a flushing system (manual or automatic), which is used to carry out periodic "washing" with fresh water and to ensure efficiency and durability of the machine and its components.
Wash the membrane with fresh water at the end of cycle production for about 3 minutes, at a pressure not exceeding 15 bar.
If the unit is not in use it must be rinsed every week with fresh water as the water tends to stagnate inside the membranes, causing a buildup of bacteria.
By washing through with clean water the membranes are kept clean and efficient.
Check also the pre filter cartridges periodically, if they have a dark colouring, they need to be replaced.
How to use the watermaker cleaner powder
Dissolve all the CTR powder contained in a bottle, into a perfectly clean bucket and mix it with fresh water until it is totally melted. Pour the CTR product into a 100-liter container filled with fresh water.
It is important that the capacity is large, since the regeneration process occurs within a closed circuit, so a small volume of water might be overheated, causing serious damage to the membranes.
Wash the watermaker membranes
Once the closed circuit has been created, the membranes can be washed. The regeneration process must be performed at a pressure of about 15 bar for 30 minutes.
Once the process has been completed, the regeneration tank can be emptied.
How to winterize a watermaker
Repeat the procedure above using the liquid FLD product to sterilize the membranes.
The only difference lies in the product to use. Place 100 lt of fresh water into the container and put inside all the product IDRO55(fluid).
Be careful when you handle the product, do not smell it or rub your eyes if you touched the product. Re-start the system with unchanged pressure and make the product circulate for about 15 minutes within a closed circuit keeping a 15 bar pressure.
Then, empty the regeneration tank. At this point the regeneration and winterizing operations are completed, re-set valves to running position and take off the hoses used for regeneration and winterizing.
Keep the 3-way valve in horizontal position (closed).
Idromar: one of the best watermakers!
Idromar International was founded in 1982, when water-makers for nautical use were practically unknown.
His great love for the sea and boating, led Vittorio Battino to construct the first water-maker as a hobby, having acquired the experience required working in the water purification sector.
His twenty years experience was a determining factor in the success of the first IDROMAR water-maker
Nautica Depot is the official supplier for Idromar in Sardinia and our NA Tech department is the official dealer for technical assistance on Idromar products in the island.
You can find the above products available in stock at Nautica Depot marine store in Sardinia or ready to buy online on this website.