Membrane seawater desalination technology, reverse osmosis (RO) process

In large-scale seawater desalination projects, Ba'an Water adopts reverse osmosis as the core desalination process, combined with air flotation and ceramic flat ultrafiltration membrane pretreatment processes. Desalination of seawater refers to the use of seawater desalination to produce fresh water, which is an open-source incremental technology for achieving water resource utilization. Among them, reverse osmosis (RO) membrane method is a reliable, effective, and low-cost technical means for obtaining large amounts of freshwater resources. The freshwater resources obtained by using this seawater desalination technology can meet the stable water demand for daily life, industry, and agriculture in industries such as municipal, power, oil and gas. Over the years, Ba'an Water has been deeply involved in the field of seawater desalination, and has greatly improved its professional knowledge, technical means, practical experience, and other aspects of seawater desalination. In addition to improving the freshwater recovery rate and desalination efficiency of the main process RO membrane system, which greatly enhances the economic benefits of the system, Ba'an Water has also added its independently developed dissolved air flotation (DAF) and nano ceramic flat ultrafiltration membrane (CFM) products in the pretreatment design. These two technologies can remove impurities in the influent and effectively prevent RO membrane fouling caused by factors such as organic matter, microorganisms, and inorganic salts. Due to the comprehensive influence of factors such as the location of the factory area, the quality of the incoming seawater, and seasonal changes, the pre-treatment process may contain a large amount of suspended solids (SS), colloidal pollutants, and soluble organic matter in the incoming seawater. These impurities can cause various forms of RO membrane fouling, such as colloidal fouling, inorganic scaling, and microbial fouling, thereby reducing membrane performance and lifespan. Therefore, a pre-treatment process is generally installed before the RO membrane system to remove impurities from the water and slow down the process of membrane fouling. The pre-treatment processes used by Ba'an Water include advanced DAF technology and traditional flocculation+sedimentation+filtration technology. The DAF process has a high removal rate for low-density pollutants (with a density lower than water, such as plankton, algae, and oil). Compared with traditional polymer films, CFM has the following advantages: long service life: 3-5 times; High flux: 2-10 times; Less chemical consumption: 50%; Low energy consumption: 50%; High recovery rate: up to 98%; Low backwash frequency and short time: backwash once a day, each backwash only takes 120 seconds; High mechanical strength: easy to clean. The characteristics of RO membrane technology allow for flexible selection of suitable pretreatment processes based on specific conditions; Suitable for automated seawater desalination plants; Suitable for the treatment of seawater, brackish water, and industrial wastewater; Small footprint; Easy operation and maintenance; Low energy consumption and minimal chemical consumption; Single equipment processing capacity: 1000 m3/d; Produce fresh water that meets the standards for agricultural irrigation, industrial use, and even drinking water (WHO standards); Equipped with advanced energy recovery devices to reduce energy loss. With the rapid development of membrane technology, the advantages of RO membrane seawater desalination technology have been widely promoted and applied due to its significant advantages: simple equipment; Easy to maintain; Equipment modularization; Low energy consumption; Less chemical consumption; High freshwater recovery rate; Low maintenance costs; Green circular economy.