Low-temperature evaporation crystallization equipment

Working Principle

1. Vacuum Pressure Reduction: A vacuum pump extracts gas from the evaporator, creating a low-pressure environment. Since boiling point is directly proportional to pressure, reducing pressure lowers the boiling point of the solution. For example, water boils at 100°C under standard atmospheric pressure, but in a vacuum, the boiling point may drop to around 30°C to 40°C.

2. Evaporation and Condensation: In the low-pressure environment, the solution begins to evaporate, producing vapor. This vapor is then introduced into the condenser, where it is cooled and condensed back into a liquid state, thus achieving separation of the solvent and solute.

3. Vapor Compression and Reuse: In some low-temperature evaporation systems, the vapor is further compressed by a compressor, increasing its temperature and pressure, allowing it to be recycled within the system as a heat source for heating other parts of the solution. This vapor recompression technology significantly improves the system's energy efficiency.

4. Energy Saving Characteristics: Low-temperature evaporators utilize the principle of a low-temperature heat pump, reusing the low-temperature vapor generated during evaporation after its temperature is increased by a compressor. This greatly reduces the consumption of additional heat energy and significantly lowers operating costs compared to traditional evaporation technologies. 5. Heat Exchange: Evaporators typically include heat exchangers to recover some heat energy, further improving energy efficiency.

Equipment Types

1. MVR Evaporator: Recovers secondary steam via a compressor, resulting in low energy consumption and suitability for applications with stable throughput, but requires a larger initial investment.

2. Multi-Effect Evaporator: Utilizes waste heat by connecting multiple evaporators in series, balancing energy consumption and cost, suitable for medium-sized enterprises.

3. Falling Film Evaporator: High heat transfer coefficient and short residence time, suitable for heat-sensitive materials.

4. Forced Circulation Evaporator: Drives the solution at high speed using a pump, suitable for solutions prone to scaling or with high concentrations.

5. OSLO Crystallizer: Produces large crystal particles, suitable for applications with strict crystal form requirements.

6. DTB Crystallizer: Suitable for fine chemical products requiring controlled supersaturation.

Equipment Features

1. Energy Saving and Fast: Low-temperature evaporation crystallization equipment significantly reduces energy consumption through vacuum decompression and vapor recompression technology, resulting in significantly lower operating costs compared to traditional evaporation technologies.

2. Fully Enclosed Operation: The system operates in a fully enclosed manner, minimizing the risk of exhaust gas and wastewater leakage during operation, ensuring a high safety factor and effectively preventing secondary pollution.

3. High Degree of Automation: The equipment is typically equipped with a PLC or DCS control system, enabling real-time monitoring and adjustment of temperature, pressure, and concentration, reducing manual intervention.

4. Small Footprint: Utilizing a skid-mounted, modular design, the system has a compact footprint, reducing on-site installation difficulty, investment costs, and floor space requirements.

5. High Crystallization Quality: By accurately controlling the evaporation and crystallization processes, crystals with uniform particle size and high purity can be produced.

Application Scenarios:

1. Industrial Wastewater Treatment: Used to treat wastewater containing high concentrations of salts (such as sodium chloride, sodium sulfate, sodium nitrate, etc.), corrosive ions (such as chloride ions, fluoride ions), and scaling ions (such as calcium ions, magnesium ions), achieving wastewater concentration and volume reduction, and salt recovery.

2. Chemical Product Production: Used in the production of chemical products such as sodium sulfate and sodium chloride, improving product quality through low-temperature evaporation crystallization technology.

3. New Energy Materials: Used to treat lithium cobalt oxide leachate from lithium batteries, waste acid from PV texturing, etc., recovering crystals such as sodium fluoride and sodium sulfate.

4. Biopharmaceuticals: Used to treat antibiotic yeast fermentation broth, synthetic crystallization residues, etc., extracting organic crystals and protecting heat-sensitive components.

5. Hazardous Waste Disposal: Used to treat RO concentrate from landfill leachate, incinerator fly ash eluent, etc., reducing the amount of hazardous waste.

Low-temperature evaporation crystallization equipment, due to its energy-saving, rapid, safe, and environmentally friendly characteristics, has been widely used in many fields and is an important technical means to achieve resource recovery and environmental protection.