Aquaculture UF+RO Desalination & Concentration System

System Overview and Strategic Applications

Metalsin‘s Aquaculture UF+RO Desalination & Concentration System is a sophisticated, dual-stage solution designed specifically for the rigorous demands of modern marine hatcheries and Recirculating Aquaculture Systems (RAS). By integrating ultrafiltration (UF) and reverse osmosis (RO) technologies, this system serves a vital dual purpose: it purifies seawater into high-quality fresh or brackish water for species acclimation, while simultaneously producing “concentrated seawater” for specialized breeding requirements.

A typical UF+RO desalination/concentration system for aquaculture industry: with water output capacity of 10 tons per hour, housed in a 20-feet container.

Key Applications:

• Precision Salinity Adjustment: Crucial for the “desalination” phase in shrimp and fish hatcheries to improve seedling survival rates.
• High-Density Breeding Support: Providing ultra-pure, pathogen-free water for high-density nursery environments.
• Concentrated Seawater Production: Generating high-salinity brine for specific species that require “salt-stimulus” for spawning or early-stage growth.
• Ecological RAS Management: Reducing nitrogen, phosphorus, and organic pollutants to prevent eutrophication and red tides in surrounding maritime ecosystems.

Configuration Types and Performance Parameters

To accommodate different facility footprints and environmental conditions, we offer this system in two professional configurations:

• Optimized for indoor hatcheries and high-density RAS, Metalsin‘s skid-mounted systems feature a compact, open-frame design that maximizes floor space while ensuring 360-degree accessibility. This architectural transparency allows operators to perform rapid visual inspections and immediate maintenance, which is vital for upholding strict bio-security protocols and ensuring 24/7 system uptime. By integrating seamlessly with existing indoor infrastructure, these units serve as a modular, high-performance “water heart” for aquatic facilities where space efficiency and water stability are critical to livestock survival and growth.
• Metalsin‘s containerized systems offer a rugged, “plug-and-play” solution housed in standard 20ft or 40ft shipping containers, specifically engineered for rapid outdoor deployment in harsh coastal environments. These weather-resistant units feature integrated climate control and specialized shielding against corrosive salt spray, ensuring long-term mechanical durability at remote farm sites. By providing a self-contained, mobile water treatment hub, they eliminate the need for permanent building infrastructure and can be operational almost immediately upon arrival.

Skid mounted UF+RO desalination & concentration systems for precision salinity management and bio-secure water supply in aquaculture industry.

Key Production Parameter

• Output Flow Rate: 1 m³/h to 100 m³/h (customizable)
• Desalination Rate: ≥ 99.2%
• Pure Water Salinity: < 500 mg/L (potable grade)
• Concentrated Seawater TDS: 72,000 – 210,000 mg/L (adjustable)
• Biosecurity: 99.9% removal of bacteria and viruses via UF pre-treatment.
• Input Water TDS: ≤35000 mg/L
• Operation Temperature: 5~45 °C
• Operation Pressure: ≤ 5.0 MPa
• Recovery Rate: 45%~90% (customizable)
• Output Water Turbidity: < 0.1 NTU
• Applied Materials: SS 316L, FRP, Plastic

Working Principle & Process Flow

Metalsin‘s UF+RO aquaculture water treatment system combines ultrafiltration (UF) and reverse osmosis (RO) technologies to achieve high-precision seawater purification and salinity control at room temperature. Through pressure-driven cross-flow membrane separation, the system effectively removes suspended solids, bacteria, organic contaminants, and dissolved salts, providing stable fresh water, brackish water, or concentrated seawater for hatcheries and recirculating aquaculture systems (RAS). This advanced membrane process helps create a bio-secure and highly controlled water environment for modern marine aquaculture.

The typical process workflow of the UF+RO desalination & concentration system.

The process begins with raw seawater intake through a feed pump and disc filter for primary solid removal. The water then passes through the UF precision filtration stage, where microorganisms, colloids, proteins, and bacteria are separated by microporous membranes. After pretreatment, a high-pressure pump delivers the water into the RO system for desalination and molecular separation. The system finally produces two independent water streams: purified low-salinity water for sensitive aquaculture applications and concentrated seawater for high-salinity breeding requirements. An integrated rinse system also helps prevent membrane fouling and salt crystallization, ensuring long-term operational stability.

Frequently Asked Questions (FAQ)

1. Why use a combination of UF and RO for aquaculture?

Standard filtration isn’t enough for high-density hatcheries. UF (Ultrafiltration) provides a biological barrier against viruses and bacteria, while RO (Reverse Osmosis) allows for the physical manipulation of salt levels. Together, they ensure the most stable and biosecure environment possible for sensitive seedlings.

Series-01 components: control cabinet, RO membranes, ultra-precision filter.

2. Why does aquaculture require both desalination and seawater concentration?

In industrial aquaculture, especially hatchery operations, precise salinity control is essential for improving survival rates and maintaining stable breeding conditions. Seawater is desalinated into fresh or brackish water to help aquatic species gradually adapt from marine to low-salinity environments, compensate for evaporation losses in recirculating aquaculture systems (RAS), and support low-salinity farming near coastal areas. At the same time, seawater concentration is also important because certain species require higher salinity during spawning and larval cultivation, while some hatcheries use concentrated brine as a base solution for precise water formulation. In addition, RO systems naturally generate concentrated brine, which can be recycled as a valuable high-salinity water source, helping achieve resource recovery and environmentally friendly zero-discharge aquaculture operations.

3. Why is aquaculture wastewater treatment and recycling important in modern marine farming?

In high-density marine aquaculture systems, large amounts of feed, nutrients, and disinfectants are used to support aquatic growth, which generates wastewater containing organic matter, ammonia nitrogen, suspended solids, and chemical residues. If discharged directly into the sea, these pollutants can cause eutrophication, water contamination, and harmful red tides. Modern aquaculture wastewater treatment systems use physical, chemical, and biological treatment technologies to reduce COD, SS, and ammonia levels, allowing the water to be safely recycled within recirculating aquaculture systems (RAS). This not only protects the marine environment but also reduces water consumption and improves the sustainability of industrial aquaculture operations.

Series-02 components: feed pump, high-pressure pump, disc filter.

4. Will the water treatment system vary for different aquaculture species and farming conditions?

Yes. Metalsin provides customized UF+RO water treatment solutions based on different aquaculture species, breeding requirements, water quality conditions, and environmental factors. Our engineering team designs tailored systems to meet the specific needs of each project, ensuring optimal water quality, salinity control, and operational efficiency. Welcome to contact us for customized solutions.

Find more details of RO desalination system for specialized industrial & EPC applications: