The Seven Seas Water team of experts has extensive experience in producing high-purity water for some of the most demanding industries around the world. Some of our key personnel have been involved in providing ultra-pure water solutions to one of the largest refineries in the world, and others have engineered water treatment facilities and delivered critical water to nearly half of the nuclear power stations in the United States.
Also known as sedimentation, clarification is the removal of settleable solids by gravity. Sand, grit, precipitates, pollutants, flocs, and other solids are kept in suspension in water as long as the water is flowing with sufficient velocity and turbulence. Sedimentation removes these solids by reducing the velocity and turbulence. The process takes place in large tanks called sedimentation basins. Basins designed for efficient sedimentation allow the water to flow very slowly with minimum turbulence at entry and exit points. The solids accumulate at the bottom of the basin as a sludge which must be pumped out and disposed of.
Multimedia filtration is a pressurized filtration process where water is filtered through three or more different media. The types of media used can include sand, anthracite, and garnet. This type of filtration can remove particles from 10-25 microns. They are typically operated at loading rates of 3-8 gpm/ft2. They must be backwashed periodically to remove the contaminants which become trapped in the media.
Micro filtration is a size-exclusion, pressure-driven membrane process. This technology uses microporous membranes, which can remove contaminants ranging from 0.1 to 10 μm. Microfiltration provides an effective barrier for particles, bacteria, and protozoan cysts. Operating pressures range from 5 to 30 psi.
Ultra filtration is also a size-exclusion, pressure-driven membrane process. Compared to microfiltration, UF retains much smaller particles. Molecules greater than the nominal pore size or nominal molecular weight cutoff (MWCO) are retained. Most UF systems range from 80k to 100k MWCO. This type of water treatment typically targets particulates, bacteria, protozoa, viruses, and organic molecules. Operating pressures range from 10 to 50 psi.
Seawater Reverse Osmosis and Brackish Water Reverse Osmosis are pressure-driven membrane processes. Hydraulic pressure is used to overcome the feed solution’s osmotic pressure and induces diffusion of pure water referred to as permeate, through a semi-permeable membrane. The solutes in the feed stream are concentrated during the process and leave the system as concentrated brine, also known as reject. These systems effectively remove all organic and inorganic constituents, including monovalent species. Seawater (SWRO) systems compared to brackish water (BWRO) systems are capable of more selective separation of water from other constituents in the feed stream due to higher pressures and smaller membrane pore sizes. Operating pressures for SWRO range from 750-1000 psi while BWRO ranges from 200-400 psi.
Electrodeionization is a water treatment technology used to produce ultra-pure water. It utilizes ion-exchange resins and ion-selective membranes, which are continuously regenerated by an electric current. The ion-exchange process removes ionized species from water by exchanging them for H+ and OH- ions. This type of water treatment requires no chemicals to regenerate the resin beds unlike older technologies for ultra-pure water production. The product water from an EDI system can reach very high purity (5-17 MΩ-cm) and is used for industrial processes such as steam generation/boiler feed, pharmaceutical industry, biotechnology, chemical production, laboratories, and electronics.
When it comes to engineering utilities to meet the demands of high-purity industrial applications, the Seven Seas Water team tops the list of experts in the industry. An abundance of knowledge and skill have been gained through years of experience designing, commissioning and operating water treatment facilities for global food and electronic manufacturing companies, and a multitude of power stations. Our ability to perform and deliver the critical water you need is unbeatable.