Product Introduction

　 　Multi-effect evaporation equipment It is a highly efficient and energy-saving evaporation equipment based on the principle of “steam cascade utilization + multi-stage concentration.” At its core, it adopts a “2- to 5-stage evaporator series” configuration, in which the secondary steam generated by the preceding evaporator serves as the heating source for the subsequent stage, enabling cascaded recovery and recycling of thermal energy and significantly reducing fresh steam consumption. The equipment boasts key advantages—“remarkable energy-saving performance, large processing capacity, stable operation, and wide adaptability”—and is widely used in large-scale solution concentration, salt recovery, and wastewater reduction processes across industries such as chemical engineering, salt chemical industry, environmental protection, food, and pharmaceuticals. It is particularly well-suited for handling high-water-volume, low-concentration feed liquids. Depending on the characteristics of the feed liquid (such as viscosity, corrosivity, and thermal sensitivity), production capacity requirements (from 1 ton/hour to 500 tons/hour), and energy-saving objectives, we can customize the number of effective bodies, the type of evaporator (falling film / forced circulation / natural circulation), and process parameters accordingly.

Product Category

　　Based on the combination form of the effect units, the type of evaporator, and the application scenario, multi-effect evaporation equipment is mainly categorized as follows:

　　1. Classified by the number of effective entities

　 　▪ Dual-effect evaporation equipment: Two-stage evaporators connected in series reduce energy consumption by 40% to 50% compared to single-effect equipment. They feature a simple structure and low investment costs, making them suitable for small- and medium-scale production capacities (1 t/h to 50 t/h), such as concentration in the food industry and treatment of small-scale chemical wastewater.

　 　▪ Triple-effect evaporation equipment: A three-stage evaporator in series reduces energy consumption by 60% to 70% compared to single-effect equipment. It is the mainstream type for industrial applications and is suitable for medium- to large-scale production capacities (50 t/h to 200 t/h), such as concentration in salt chemical industries and wastewater treatment in chemical parks.

　　 ▪ Four-effect / Five-effect evaporation equipment: Evaporators of Grade 4-5 are connected in series, reducing energy consumption by 70%-85% compared to single-effect equipment. This configuration is particularly suitable for ultra-large-scale production capacities (200 t/h – 500 t/h) and scenarios with high energy demands, such as seawater desalination and zero-discharge treatment of large-scale coal chemical wastewater.

　　 ▪ Multi-effect + MVR combined equipment: The pre-stage employs multi-effect cascaded energy utilization, while the post-stage is equipped with an MVR compressor to recover the secondary steam from the final effect. This results in a further 30%–50% reduction in energy consumption compared to conventional multi-effect equipment, making it ideally suited for applications requiring extreme energy efficiency.

　 　2. Classification by Evaporator Type

　 　▪ Multi-effect falling-film evaporation equipment: All levels employ falling-film evaporators, which offer high heat transfer efficiency and short residence times for materials—making them ideal for heat-sensitive, low-viscosity feed liquids (such as food concentrates and pharmaceutical intermediates).

　　 ▪ Multi-effect forced-circulation evaporation equipment: All levels employ forced-circulation evaporators with strong anti-scaling capabilities, making them suitable for feed liquids with high salt content, high viscosity, and a tendency to crystallize (such as in salt chemical industries and high-salt wastewater treatment).

　 　▪ Hybrid multi-effect evaporation equipment: The pre-stage uses a falling-film evaporator (for efficient concentration), while the post-stage employs a forced-circulation evaporator (suitable for handling high-concentration, fouling-prone feed liquids). This configuration is well-suited for complex feed liquids—such as chemical wastewater with large concentration gradients and a tendency to foul.

　　 ▪ Multi-effect natural circulation evaporation equipment: All levels employ natural-circulation evaporators, which feature low energy consumption and simple maintenance, making them ideal for large-scale feed liquids with low viscosity and resistance to scaling (such as concentrated clear water and pre-treatment of low-salt wastewater).

Performance Features

　　 1. Significant energy-saving effect: By utilizing secondary steam in a staged manner, fresh steam consumption is significantly reduced. The more effect units there are, the more pronounced the energy-saving effect becomes—specifically, a two-effect unit consumes half the steam of a single-effect unit, a three-effect unit consumes one-third, and a five-effect unit consumes only one-fifth. This results in energy savings of 60% to 85% compared to a single-effect unit.

　 　2. Large processing scale: The evaporation capacity of a single unit can range from 1 ton/hour to over 500 tons/hour. The modular design supports parallel expansion and is well-suited for large-scale, continuous production (such as centralized wastewater treatment in chemical parks and mass production in the salt-chemical industry).

　 　3. Stable and reliable operation: The parameters of evaporators at all levels—temperature, pressure, and liquid level—are linked for coordinated control, with automated adjustments implemented via a PLC system to prevent shutdowns caused by dry walls or scaling. Multi-stage evaporation ensures a gradual concentration gradient of the feed solution, thereby reducing the risk of crystal adhesion.

　 　4. Wide compatibility: It can handle various solutions with solute concentrations ranging from 5% to 30% and viscosities up to 500 mPa·s. It is compatible with feed liquids spanning low to medium-to-high viscosity levels and containing small amounts of suspended solids (≤3%). By customizing materials—such as 304 stainless steel, 316L stainless steel, titanium, and Hastelloy—it can be adapted for corrosive media including acidic, alkaline, and saline solutions.

　 　5. Flexible operation: By adjusting parameters such as the number of effect units, steam pressure, and vacuum level, the evaporation rate and concentration can be flexibly controlled to suit either batch or continuous production. Some equipment supports switching between single-effect and multi-effect operation, meeting diverse capacity requirements.

　 　6. Green Economy: Closed-loop operation reduces solvent volatilization and pollution; the condensate recovery rate is ≥90%, enabling the recycling of water resources. It consumes less fresh steam, thereby lowering coal- or gas-fired energy costs while also reducing carbon emissions, in compliance with environmental protection policies.

　　 7. Low maintenance costs: The modular design facilitates easy disassembly and maintenance; evaporators at each stage can be cleaned and maintained individually without requiring a complete system shutdown. The natural circulation/falling-film type features no vulnerable components such as forced-circulation pumps, resulting in a low risk of failure.

Application scenarios

　　Multi-effect evaporation equipment, with its core advantages of stepped energy saving and large-scale processing, is widely used in the following industries:

　　 1. Chemical industry: Concentration of salt solutions (sodium chloride, potassium chloride, sodium sulfate); concentration of chemical raw materials (ethylene glycol, propylene glycol, diethylene glycol); recovery of organic solvents (methanol, ethanol, acetone); reduction of chemical wastewater volume (concentration of dye and coating wastewater).

　 　2. Salt chemical industry: Industrial salt production (concentration and crystallization of sea salt and lake salt), special salt purification (potassium nitrate, ammonium chloride, potassium dihydrogen phosphate), and salt sludge recovery (recovery of salt crystals from saline wastewater).

　 　3. Environmental Protection Industry: Zero discharge of high-salinity wastewater (wastewater from chemical parks, electroplating wastewater, and coal chemical wastewater); concentration of leachate from municipal solid waste (reducing subsequent treatment costs); concentration and volume reduction of organic wastewater (printing wastewater, coating wastewater).

　 　4. Food industry: Large-scale juice concentration (orange juice, apple juice, tomato juice), sucrose/maltose syrup concentration, dairy product concentration (milk, whey protein), food additive concentration (citric acid, lactic acid);

　 　5. Pharmaceutical Industry: Large-scale concentration of Chinese medicinal extracts, concentration of antibiotic solutions (such as penicillin and cephalosporin-based antibiotics), treatment of pharmaceutical wastewater (recovery of solvents and water resources), and concentration of biological preparations (pre-processing of enzyme preparations and vaccine raw materials).

　 　6. Other fields: Desalination (large-scale freshwater production), black liquor concentration in the paper industry (lignin recovery), electroplating solution recovery (concentration and reuse of spent chromium- and zinc-plating solutions), and lithium battery material production (concentration of lithium salt solutions).