Product Introduction

　　 Multi-stage Flash Evaporator (MSF) It is a large-scale continuous evaporation device based on the “flash evaporation” principle. At its core, it employs a “multi-stage series + pressure-reducing flash evaporation” technology. The preheated feed liquid is sequentially introduced into flash chambers with progressively decreasing pressure, where its latent heat is utilized to rapidly vaporize water without the need for direct heating of the feed liquid, thus achieving concentration efficiently. The equipment boasts key advantages—large processing capacity, exceptional anti-scaling performance, stable operation, and low-temperature operation—and is widely used in large-scale solution concentration, zero-discharge treatment of high-salinity wastewater, and water resource recovery processes in industries such as seawater desalination, chemical engineering, and environmental protection. It is particularly well-suited for handling materials that are high in salt content, have high hardness, and are prone to scaling. The number of stages and modular design can be customized according to production capacity requirements—from several thousand tons per day up to tens of thousands of tons per day.

Product Category

　　According to the number of flash stages, operating pressure, and application scenarios, multi-stage flash evaporators are mainly categorized as follows:

　　1. Classified by flash stage

　　 ▪ Small multi-stage flash evaporator (10–20 stages): Processing capacity: 500–5,000 t/d; suitable for small- and medium-scale high-salinity wastewater treatment and industrial pure water production.

　 　▪ Medium-sized multi-stage flash evaporator (20–40 stages): Processing capacity: 5,000–20,000 t/d; suitable for integrated wastewater from chemical industrial parks and large-scale seawater desalination projects.

　 　▪ Large-scale multi-stage flash evaporator (40–80 stages): With a processing capacity of over 20,000 t/d, it is specially designed for ultra-large-scale seawater desalination and zero-discharge of high-salinity wastewater from coal chemical industries/power plants.

　　2. Classified by operating pressure

　 　▪ Atmospheric Multi-Stage Flash Evaporator: The operating pressure is close to atmospheric pressure, and the flash evaporation temperature ranges from 80 to 100℃, making it suitable for large-scale concentration applications with no strict temperature limitations.

　 　▪ Vacuum multi-stage flash evaporator (segmented vacuum): The pressure in flash chambers at various levels decreases stepwise (from 0.02 MPa to 0.001 MPa), with flash temperatures ranging from 40 to 80℃, making it suitable for heat-sensitive materials and meeting low-temperature energy-saving requirements.

　　▪ Pressurized-depressurized combination: The front stage features pressurized preheating, while the rear stage employs depressurized flash evaporation, striking a balance between preheating efficiency and low-temperature operation, making it ideal for handling high-concentration materials.

　 　3. Classified by thermal energy recovery method

　　 ▪ Single-effect recovery type: The secondary steam generated by flash evaporation is directly condensed and recovered, featuring a simple structure and low investment cost.

　　 ▪ Multi-effect recovery type: The heat from secondary steam is recovered to the feed liquid via heat exchange tubes, preheating the feed liquid while simultaneously cooling the steam, thereby increasing thermal efficiency to 70%-85%.

　 　▪ Heat pump-assisted: By pairing with a steam compressor to recover waste heat from secondary steam, energy consumption is reduced by 30% to 50% compared to conventional models, making it suitable for applications with high energy consumption requirements.

Performance Features

　 　1. Large processing scale: A single unit can handle capacities ranging from 500 t/d to 50,000 t/d, making it the equipment of choice for large-scale evaporation processes—particularly well-suited for seawater desalination and centralized treatment of wastewater from large-scale chemical industrial parks.

　 　2. Extremely strong anti-scaling capability: The feed liquid does not come into direct contact with the heating surface; instead, it is indirectly preheated via secondary steam, thereby avoiding scaling issues in the heating tubes. The flash evaporation process is rapid and uniform, with no local overheating, significantly reducing crystal deposition. The equipment can operate continuously for a period of 6 to 12 months.

　 　3. Stable and reliable operation: It features no vulnerable components such as forced-circulation pumps or liquid distributors; its structure is modular, and operational parameters (pressure, temperature, and liquid level) can be automatically controlled. It has a low failure rate and requires minimal maintenance costs.

　　 4. Low-temperature and gentle operation: The flash evaporation temperature typically ranges from 40 to 100℃. By using a vacuum system, the temperature can be controlled below 60℃, thereby preventing the decomposition of heat-sensitive materials and reducing corrosion of equipment caused by corrosive media.

　 　5. Wide compatibility: It can handle solutions with salt concentrations ranging from 5% to 25% and high hardness (calcium and magnesium ion content > 1000 mg/L). It is compatible with materials containing a small amount of suspended solids (≤3%). By customizing the material—such as using duplex stainless steel or titanium—it can also be adapted for highly corrosive media.

　 　6. High thermal energy utilization rate: The multi-effect heat recovery design boosts thermal efficiency to 70%-85%. When large-scale equipment is paired with a heat pump system, the energy consumption per ton of water evaporated can be as low as 30-50 kWh/t, yielding significant energy-saving effects.

　　 7. Flexible operation: By adjusting the operating level and flash pressure, precise control of production capacity and concentration can be achieved. The system supports both batch and continuous operation modes, making it suitable for a variety of operational conditions.

Application scenarios

　　Multi-stage flash evaporators, with their core advantages of large-scale processing and strong anti-scaling capabilities, are widely used in the following industries:

　 　1. Desalination: Large-scale freshwater production in coastal cities, islands, and ships—where a single unit can produce tens of thousands of tons of freshwater per day—is one of the mainstream technologies in global seawater desalination projects.

　 　2. Environmental Protection Industry: Zero-discharge of high-salinity wastewater from chemical industrial parks (such as coal-to-chemicals and petrochemical wastewater), treatment of flue gas desulfurization wastewater from power plants, deep concentration of landfill leachate (COD > 50,000 mg/L), and recovery of high-salinity wastewater from electroplating processes;

　　 3. Chemical Industry: Large-scale crystallization in the salt chemical industry (e.g., continuous production of sodium chloride and potassium chloride); concentration of chemical raw materials (e.g., concentration of caustic soda and soda ash solutions); recovery of organic salt solutions (e.g., potassium acetate and ammonium dihydrogen phosphate).

　 　4. Energy Industry: Concentrated reuse of circulating cooling water from nuclear power plants and thermal power plants; treatment of wastewater generated from coalbed methane extraction; resource recovery and reuse of wastewater from shale gas extraction.

　 　5. Other fields: Saline-alkali land improvement (desalination of brackish water), treatment of high-salt wastewater from large-scale pharmaceutical and food enterprises, and centralized water resource recycling projects for industrial parks.