Industrial Seawater Desalination System: Transforming Seawater into Industrial Pure Water

Coastal industrial zones often face the challenge of freshwater resource shortages. Seawater desalination provides an effective solution to the water supply bottleneck faced by industrial enterprises. Large-scale seawater desalination processes primarily adopt reverse osmosis membrane technology to convert high-salinity seawater into pure water that meets industrial requirements.

First, seawater enters the sedimentation basin through the intake structure and gravity pipeline, where large particles of sand and gravel undergo preliminary settling. It then passes through an automatically cleaned fine screen and self-cleaning filter in sequence. Subsequently, we dose sterilizing agents such as sodium hypochlorite into the water to prevent marine organisms from growing inside the pipelines and equipment. The seawater is then lifted to a flocculation sedimentation basin or dissolved air flotation unit to remove algae and fine suspended solids, after which it undergoes further purification through multi-media filters. However, a reducing agent must be added to the feed water to eliminate residual chlorine, thereby protecting the polyamide reverse osmosis membranes.

The core process is high-pressure reverse osmosis. Seawater pressurized by the high-pressure pump enters the high-rejection seawater desalination reverse osmosis membrane modules. Under a pressure of approximately 5.5–7.0 MPa, water molecules pass through the membranes to become desalinated water, while salts are rejected and form concentrated brine. The first-stage RO permeate has a salt content of approximately 200–500 mg/L. If higher-purity water is required, the permeate proceeds to a second-stage RO or continuous EDI unit for further demineralization, ultimately yielding industrial pure water with a resistivity greater than 5 MΩ·cm or even higher. This pure water can be directly used for boiler feed water, process cleaning, and other applications. An energy recovery device transfers the pressure energy from the concentrated brine to the feed water, thereby significantly reducing energy consumption. We provide containerized and skid-mounted seawater desalination equipment. These units can be deployed rapidly and reliably deliver high-quality industrial water to coastal industrial bases on a stable basis.