Reverse Osmosis FAQ's
Q: Why is the product water from an RO unit aggressive towards a vessel's plumbing?
A: Water created by an RO system will have a lower ph (acidic) due to carbon dioxide dissolved in the product water. The water also has small amounts of chlorides (salts) in the water. This combination make the water more aggressive to certain materials.
Q: What is the suggested piping material going to and from the RO unit?
A: The main objective is to avoid using materials that are subject to corrosion. One option is to use Schedule 80 PVC piping & fittings. A second option is to use 90/10 Cu/Ni piping with bronze fittings. A third option is to use 316 stainless steel piping and fittings.
Q: Is there another option to lower the aggressiveness of the RO product water if the recommended piping material is not a viable option?
A: Install a water neutralizing unit (mineralizer) at the RO unit. This would add minerals to the product water that will make the ph neutral and reduce the aggressiveness of the water and less likely to corrode piping.
Q: What are the requirements for the permeate discharge?
A: The permeate discharge can overcome a 25 psig or 60 ft of head back pressure. A check valve should be provided in the discharge line unless the discharge is to atmospheric pressure.
Q: What are the requirements for the brine concentrate discharge?
A: The brine concentrate discharge can overcome a 25 psig or 60 ft of head back pressure and a check valve should be provided in the discharge line unless the discharge is to atmospheric pressure.
Q: What are the guidelines for the feed water supply?
A: The feed water is to be supplied to the watermaker at a minimum pressure of 30 psig or 70 ft of head. If suitable pressure is not available, a feed water booster pump is recommended.
Q: What pretreatment of the seawater is required?
A: We recommend an 80-120 mesh duplex strainer to filter water from the sea chest then a multi-media filter and a 10 micron cartridge filter.