Application Background
MVR (Mechanical Vapor Recompression) evaporators are highly energy-efficient evaporation and concentration systems widely used in industries such as chemicals, pharmaceuticals, food and beverage, biotechnology, lithium battery materials, and environmental wastewater treatment. Their operating principle is to compress secondary steam using a mechanical compressor, increasing its temperature and pressure so it can be reused as the heating source. This enables efficient thermal energy recycling, significantly reducing steam consumption and operating costs.
In recent years, driven by increasingly stringent energy-saving and carbon reduction policies, MVR technology has been widely adopted in solvent recovery, distillation processes, pharmaceutical wastewater treatment, and chemical wastewater treatment due to its low energy consumption, high level of automation, and reduced operating costs. It has become an essential solution for manufacturers seeking greener production and improved energy efficiency.
Application Challenges
Stable operation of an MVR evaporator relies on precise liquid level measurement. During the evaporation process, an excessively high liquid level may cause liquid carryover into the secondary steam system, affecting compressor performance, while an excessively low liquid level can lead to circulation pump cavitation, reduced heat transfer efficiency, and even interruption of continuous plant operation. Therefore, accurate and reliable level measurement is critical to both system efficiency and operational safety.
In addition, MVR applications often involve high-temperature, high-humidity, high-viscosity, crystallizing, or corrosive media. Conventional pressure instruments are susceptible to measurement drift, blockage, or diaphragm damage under these conditions. As a result, level measurement devices must provide excellent long-term stability, reliable sealing performance, and superior corrosion resistance.
LEEG Solution
To meet the demanding requirements of MVR evaporation systems, LEEG provides the SMP858-NST and SMP858-NSF Differential Pressure Transmitters for continuous and reliable liquid level measurement. Both models feature a dual remote diaphragm seal with capillary tubes and 2-inch tri-clamp process connections. The high-pressure and low-pressure diaphragm seals are installed at the lower and upper measuring points of the evaporator vessel, enabling continuous level measurement by detecting the hydrostatic pressure differential generated by the liquid column.
In this application, both transmitters are configured with a measuring range of 0~4 mH₂O, fully meeting the liquid level control requirements of MVR evaporators. The remote diaphragm seal design isolates the sensing element from the high-temperature process medium, minimizing the influence of temperature fluctuations on measurement accuracy while ensuring excellent long-term stability.
The dual remote diaphragm seal configuration is particularly suitable for high-temperature and high-humidity environments, while also handling crystallizing, high-viscosity, and particle-laden media effectively. It helps prevent impulse line blockage and reduces maintenance requirements. Meanwhile, the 2-inch tri-clamp connection allows quick installation and removal, making it especially suitable for pharmaceutical and fine chemical applications where hygiene and maintenance efficiency are critical.
Application Benefits
After installation, the LEEG pressure transmitters continuously provide stable and accurate level signals to the PLC or DCS control system, enabling automatic liquid level control and ensuring that the MVR evaporator operates within its optimal process conditions. Reliable level measurement not only minimizes the risk of compressor shutdowns but also improves evaporation efficiency and energy utilization, ensuring stable and continuous plant operation.
With outstanding environmental adaptability and long-term measurement stability, the LEEG SMP858 Series Pressure Transmitters have been successfully applied in MVR systems for solvent recovery, distillation, pharmaceutical wastewater treatment, and chemical wastewater treatment, delivering accurate and dependable liquid level measurement solutions that help customers achieve greater energy efficiency, lower operating costs, and smarter process automation.
