Seawater desalination, as an important solution to the global water shortage problem, has attracted numerous research institutions and enterprises to invest significant resources in research and development. With the continuous advancement of technology and the gradual reduction of costs, seawater desalination technology is gradually moving from the laboratory to large-scale industrial application. This article will explore the current status of technology application in seawater desalination, the mainstream methods, and their development trends.  I. Overview of Desalination Technology Seawater desalination refers to a technology that removes salt from seawater through a series of processes, thereby obtaining fresh water. This technology is not affected by time, location, or climate, and can increase the total amount of fresh water, providing strong support for solving the problem of water scarcity. Globally, more than a hundred research institutions in over ten countries are dedicated to the research of seawater desalination, and have developed various types of seawater desalination facilities with different structures and capacities. These facilities are widely distributed in coastal areas, providing stable freshwater supply for local residents and industrial production.  II. Mainstream Desalination Technologies At present, the mainstream desalination technologies in the market mainly include two categories: distillation method and membrane method. Distillation is a method that involves heating seawater to cause it to evaporate, then condensing and collecting the steam to obtain fresh water. This method has a long history and mature technology, mainly including multi-stage flash distillation (MSF), low-temperature multi-effect (LT-MED), and pressure vapor distillation (MVC) technologies. Multi-stage flash distillation and low-temperature multi-effect technologies mainly use steam as the heat source and are often combined with power plants, extracting the waste steam from turbines to produce distilled water. The pressure vapor distillation technology utilizes heat pump evaporation technology and only uses electrical energy, making it suitable for island regions without heat sources. Membrane-based seawater desalination technology is mainly represented by reverse osmosis (RO) technology. This technology utilizes semi-permeable membranes, allowing water to pass through under pressure while retaining salt and impurities. With the continuous improvement of membrane materials and the reduction of manufacturing costs, reverse osmosis technology has become one of the mainstream methods for seawater desalination. Modern reverse osmosis devices typically use spiral wound membrane elements made of polymer composite materials, featuring high water production capacity, low energy consumption, and ease of maintenance.  III. Technological Innovation and Development in Desalination of Seawater In recent years, seawater desalination technology has made significant progress in areas such as material innovation, process optimization, and intelligent operation. In terms of material innovation, the development of new composite adsorption methods and selective ion pump components has provided more options for seawater desalination. For instance, Israel has made significant breakthroughs in the new composite adsorption method, with a special fractal-structured iron oxide - activated carbon matrix capable of forming highly efficient adsorption of chloride ions under normal temperature conditions. The EU's freshwater project has increased the desalination efficiency of seawater by 45% through the development of selective ion pump components. In terms of process optimization, the application of innovative technologies such as the double membrane method, the technology of preheating residual water and supplementing water, and membrane distillation technology has further enhanced the efficiency and economy of seawater desalination. For instance, the residual water preheating and water supplementation technology pioneered by the Suhar Power Plant in Oman has reduced the specific power consumption of the multi-stage flash evaporation equipment. The team from MIT and Xiamen University have made new progress in membrane distillation technology, respectively, by adopting superhydrophobic PTFE air gap membranes and using turbulent enhancement methods with ultrasonic irradiation to improve the flux and salt resistance performance of the membrane distillation components. In terms of intelligent operation, with the application of digital tools and the accumulation of engineering experience, the operation and maintenance management of seawater desalination projects has become more refined and efficient. For instance, a pilot test conducted by a research team in Zhejiang Province on the pulse injection mode of chemicals showed that a three-frequency periodic cleaning method could reduce the deposition of impurities by 42%. The cross-checking system adopted by a seawater desalination plant in Quanzhou that has been in operation for eight years has significantly reduced maintenance costs.  IV. Future Prospects of Desalination Technology In the future, seawater desalination technology is expected to make breakthroughs in both micro-portable devices and the new industrial circulation systems for large-scale projects. The micro-portable devices developed based on microfluidic principles can meet the freshwater demands in remote areas and emergency situations. At the same time, improving the new industrial circulation system for large-scale projects will promote the application and promotion of seawater desalination technology on a larger scale.      Furthermore, with the intensification of climate change and the growing severity of water shortage issues, desalination technology will become an important option for more countries and regions to address their water resource problems. Governments, enterprises and research institutions should strengthen cooperation to jointly promote the research and application of desalination technology, and contribute to the sustainable development of humanity.

    Firstly, distillation is one of the earliest methods applied for seawater desalination. This method uses distillation equipment to heat seawater to its boiling point, generating steam, and then condensing the steam into fresh water. During this process, salt and other impurities remain in the seawater, achieving the purpose of seawater desalination. The advantage of distillation is that it can completely remove salt and impurities, obtaining pure fresh water. However, distillation requires a large amount of energy to heat the seawater, is costly, and the equipment is bulky, making it unsuitable for large-scale application.    Secondly, reverse osmosis is one of the most widely used seawater desalination technologies at present. This method uses high pressure to filter seawater through semi-permeable membranes, allowing water molecules to pass through the membrane while salt and impurities are retained outside the membrane. Through this process, high-quality fresh water can be obtained. The advantage of reverse osmosis is that the process is simple, the equipment is small in size, and it is suitable for various scales of production. However, reverse osmosis requires a large amount of energy to generate high pressure, and the cost of the semi-permeable membrane is also high.    Finally, ion exchange is a method that uses specific resins to remove salt and impurities from seawater. This method utilizes ion exchange resins to adsorb salt ions and impurities in seawater, thereby obtaining fresh water. The advantage of ion exchange is that the operation is simple, the equipment cost is relatively low, and it can also obtain high-quality fresh water. However, ion exchange resins require regular replacement and regeneration, and the cost is high. Moreover, they have high requirements for water quality.     In summary, distillation, reverse osmosis, and ion exchange are currently the most widely used seawater desalination methods. Each method has its unique advantages and limitations, and the appropriate technology should be selected based on specific circumstances. In the future, with the development of technology and the sustainable utilization of energy, it is believed that seawater desalination technology will become increasingly mature, providing better solutions to the problem of water shortage.

Introduction to Pure Solar Direct Drinking Water Equipment Pure solar direct drinking water equipment is a high-tech water purification system that completely relies on solar energy as the sole energy source to purify untreated or polluted raw water (such as river water, lake water, well water, brackish water, and even seawater) to meet the standard for direct drinking. It integrates solar photovoltaic power generation technology and efficient water treatment technology (mainly reverse osmosis RO technology), and is specifically designed to solve the problem of safe drinking water in areas without reliable power grid coverage, with scarce water resources or poor water quality (such as remote villages, islands, pastoral areas, field operation camps, disaster-stricken areas and environmental monitoring stations, etc.). Its core objective is to achieve energy self-sufficiency, zero carbon emissions, simple operation and convenient maintenance of drinking water supply. Core characteristics100% solar-poweredEnergy independence: Completely free from reliance on the power grid or fossil fuel generators, it can operate as long as there is sunlight.Zero carbon emissions: The operation process does not produce any greenhouse gases or environmental pollution, making it a truly green and environmentally friendly technology.Strong adaptability: Particularly suitable for remote and isolated areas with insufficient grid coverage or no grid at all.Produce high-quality direct drinking waterDeep purification: Mainly using reverse osmosis technology, it can effectively remove the vast majority of dissolved salts in water (with a desalination rate of over 95-99%), heavy metal ions, organic matter, bacteria, viruses, colloids and other impurities.The purified water quality meets the national and international (such as WHO) hygiene standards for direct drinking water and has a sweet taste.High integration and intelligenceIntegrated design ​​ Typically, solar panels (photovoltaic panels), solar charging controllers, energy storage batteries (for power supply in the dark or weak light), high-pressure pumps, reverse osmosis membrane modules (RO membranes), pre-treatment filters (such as PP cotton, activated carbon), post-treatment antibacterial devices (such as ultraviolet sterilizers or activated carbon filters), and intelligent control systems are integrated on a compact frame or mobile platform.Automatic operation: Through the intelligent controller, the equipment can automatically start and stop the high-pressure pump based on the intensity of light, optimize the system operation, and achieve unattended operation. It usually has self-protection functions (such as water shortage protection, high and low pressure protection, etc.).Status monitoring: It can be equipped with a display screen or a remote monitoring module to show the working status (such as water production flow, water quality TDS value, battery power, system pressure, etc.).Energy conservation and efficiency improvementThe high-pressure pump is directly driven by solar power and has high efficiency.The controller optimizes the matching of solar input power and the power required by reverse osmosis to improve energy utilization rate.Some systems may utilize solar heat for low-temperature heat utilization assistance or adopt high-efficiency variable-frequency pump technology.Modularization and scalabilityIn design, the modular concept is often adopted, which facilitates the increase of solar panel area, battery capacity and the number of reverse osmosis membranes according to the actual water consumption demand.It can be flexibly deployed as a fixed, mobile (such as vehicle-mounted or ship-mounted) or emergency portable device.Simple maintenance and low operating cost:The main consumables are the pretreatment filter element and RO membrane element. Under normal circumstances, they can be replaced regularly (depending on the quality of the source water and the water consumption).Energy is free, and the main operating cost is the expense of replacing consumables.It has a high degree of automation, greatly reducing the need for manual intervention.Wide range of application scenariosRemote rural areas, pastoral areas, islands and other regions without or with weak power grids.Field research, exploration, surveying and mapping, and engineering construction camps.Border guard posts and emergency disaster relief sites.Ships, island villas, ecological farms.As a sustainable infrastructure, it contributes to the global clean drinking water program. Summary: The pure solar direct drinking water equipment captures sunlight and converts it into electrical energy to drive the pretreatment, high-pressure pump and disinfection device. By using the physical screening principle of reverse osmosis membranes, it separates various impurities from water molecules under pressure, ultimately producing pure water that can be drunk directly. Its core value lies in the complete autonomy of its energy, the high reliability of its purification effect, as well as its significant social benefits and environmental friendliness in solving the drinking water problem in specific areas.

    Rural domestic sewage treatment and resource utilization, promoting the high-quality development of rural ecological agriculture, the first "pure solar integrated sewage utilization and treatment equipment" in the country. The Youfangzhuang pure solar integrated sewage utilization and treatment equipment project, which was built in He 'an Village, Mengcheng County with the assistance of the Provincial Department of Ecology and Environment, has been completed and put into use, solving the problem of domestic sewage treatment and resource utilization for the villagers of this village. It has turned sewage into treasure and further improved the construction map of a beautiful and harmonious village in He 'an Village. On the afternoon of August 8, 2024, the Provincial Department of Ecology and Environment led a team to visit He 'an Village in Mengcheng County. They conducted an on-site inspection of the completion and operation of the country's first pure solar integrated sewage utilization and treatment equipment jointly developed by Bengbu University and Baolu Optoelectronics Co., LTD.The successful operation of this equipment has completely solved the problem of local villagers' domestic sewage treatment and turning waste into treasure, setting a new benchmark for the deep integration of green energy and environmental protection.This innovative achievement not only injects strong impetus into the improvement of the local ecological environment, but also provides a highly referential example for sewage treatment in other regions. The sewage treatment station of He 'an Village was completed in July 2024, with a daily treatment capacity of 10 cubic meters, and the raw water is domestic sewage from farmers. This project adopts the "Solar Integrated Sewage Treatment Equipment (Patent No. :ZL201921370010.9)" developed by our company, and selects the integrated multi-stage aerobic + micro air flotation process (SAOF). Through quantitative lifting and fine management, it has achieved long-term stable compliance with discharge standards and can be pumped for irrigation for resource utilization.The "first pure solar power supply + intelligent pumping irrigation system in the country" put into use in this project represents the gratifying achievements made by Bengbu University and Baolu Optoelectronics in the in-depth development of school-enterprise cooperation. It is also a major breakthrough in sustainable environmental governance technology, truly achieving self-sufficiency in sewage treatment and zero pollution discharge. This innovative move not only effectively solves the problem of rural sewage treatment, but also opens up a new path for the improvement of the rural ecological environment and the sustainable utilization of resources. In the future, this technology is expected to be more widely promoted and applied across the country, driving the rural sewage treatment cause in our country to a new level, contributing more to the construction of beautiful villages and ecological civilization, enabling the vast rural areas to have a broader path of green development, and allowing farmers to enjoy a more beautiful ecological environment and a more prosperous life.