Three main problems of desalination: Issue 1 Environmental impact ● Brine discharge ● Use of chemicals ● Long-term impact on marine ecology Issue 2 High energy consumption ● Scale of energy consumption ● Energy sources and environmental impact ● Restrictions on renewable energy Issue 3 Economic cost ● Initial investment and operating costs ● Water prices and economic feasibility ● Funding and resource allocation

The process flow of a desalination plant is usually divided into 5 steps: 1. Seawater intake 2. Pretreatment 3. Core desalination process 4. Post-treatment 5. Concentrate discharge

From the above analysis, it can be seen that a large-scale reverse osmosis desalination plant with a processing capacity of 500,000 cubic meters per day consumes about 1.5 million to 3 million kWh of electricity in one day of operation.

The main types of water treatment plants are: 1. Drinking water treatment plants, 2. Sewage treatment plants, 3. Industrial water treatment plants, 4. Seawater desalination plants.

The initial construction cost of the Sorek Desalination Plant was about $400 million, while the construction cost of the Carlsbad Desalination Plant was as high as $1 billion. As the world's largest desalination plant, the Ras Al Desalination Plant cost as much as $7.3 billion to build.

The Ras Al-Khair Desalination Plant is the world's largest hybrid desalination plant, combining multi-stage flash and reverse osmosis (RO) technologies, with a total capacity of 1.025 million cubic meters per day. Among them, the reverse osmosis part has a capacity of 725,000 cubic meters per day.

Small household desalination plants are suitable for households on remote islands or coastal areas, and the water production capacity is usually 100 to 500 liters per hour. Such plants are relatively affordable, generally between US$2,000 and US$10,000.

Solar seawater desalination usually uses solar evaporation devices to heat seawater until it evaporates, and then collects fresh water through condensation. In this way, drinking water can be produced at low cost and with low energy consumption. In addition, the solar desalination device can be adjusted according to actual needs and is suitable for small-scale and large-scale production.

1. Cost range: According to the World Bank, the cost of solar desalination typically fluctuates within a range per cubic meter of water produced. The average cost is approximately US$0.72-1.50, depending on a variety of factors, including technology selection, energy costs, equipment and material costs, and the geographical and climatic conditions of the project location.

A seawater treatment plant, also known as a desalination plant, is a facility that converts seawater into fresh water through desalination technology. Its main technologies include reverse osmosis (RO), multi-stage flash evaporation (MSF) and multi-effect distillation (MED). Reverse osmosis is currently the most common desalination technology. It uses high pressure to force seawater through a semi-permeable membrane, removing salt and other impurities, and ultimately obtaining pure fresh water.