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The production process of salt-making equipment uses brine as raw material; through evaporation and concentration, NaCl is precipitated, and after dehydration and drying, it becomes a qualified product. During the operation of vacuum salt production equipment, the measurement of the liquid level in the evaporation tank and the solid-liquid ratio are important process parameters in the salt evaporation stage. If these values exceed the specified ranges, it can easily disrupt the process balance, having an adverse effect on production. If the liquid level in the evaporation tank is too high, it not only slows down the circulation rate of the material and increases the static pressure, thereby reducing the effective temperature difference between the heating steam and the material and thus lowering the evaporation rate and affecting production capacity, but it also causes the secondary steam to contain salts, which accelerates corrosion of the equipment in the lower heating chambers and affects the quality of the condensate water. If the liquid level is too low, the static pressure decreases, leading to boiling of the material inside the heating tubes; this accelerates the formation of scale, causing the heating tubes to become clogged and resulting in a halt in production. Therefore, during the production process, the liquid level in the evaporation tank must be kept within a reasonable range. Given the importance of controlling the liquid level in the evaporation tank, as well as the intense boiling of brine during the evaporation process which can lead to corrosion and crystallization, the methods for monitoring the liquid level in the evaporation tank are described below. Accurate measurement of the liquid level in evaporation equipment in salt production is an extremely important parameter in the entire salt production process. Ultrasonic level measurement is widely used for this purpose, thanks to the advantages of ultrasonic waves: their ability to be directed easily, their good directionality, easy control of intensity, and the fact that they do not require direct contact with the object being measured. During measurement, pulsed ultrasonic waves are emitted by a sensor (transducer); the sound waves are reflected off the surface of the object and then received by the same sensor, where they are converted into electrical signals. The distance from the sensor to the object being measured is calculated based on the time between the emission and reception of sound waves. A MaxBotix ultrasonic level sensor from Gongcaiwang – the MB7389 and MB7380 – represents a cost-effective solution for the applications that require it. Accuracy range – search, low-voltage operation, space-saving, low cost, and IP67 weather resistance. The hrxl-maxsonar-wr sensor cable provides high-precision, high-resolution ultrasonic proximity detection and ranging in air. The features of this sensor cable are 1 mm resolution, target size compensation, and operating voltage compensation. To improve accuracy and better reject external noise sources, temperature compensation for the internal speed as well as optional external temperature compensation. The hnxl-maxsonar-wr/wrc model is available in 5-meter or 10-meter versions. This ultrasonic sensor can detect objects ranging from 1 millimeter to 30 centimeters in size; objects within a range of up to 30 centimeters are typically reported as 30 centimeters. The interface output format consists of pulses over RS232 (MB7360 series) or TTL (MB7380 series), along with width, analog voltage, and digital serial data. Factory calibration is standard.