A New Ultrasonic-based device for Accurate Measurement of Oil, Emulsion, and Water Levels in Oil Tanks MAHMOUD MERIBOUT 1 , MOHAMED HABLI 1 , AHMED AL-NAAMANY 1 , and KHAMIS AL-BUSAIDI 2 1 ECE Department, College of Engineering, SQU University, Oman. 2 PDO Corporation, Mucast, Oman. Abstract: - In the oil industry, many applications require the measurement of more than one liquid level interface, often in challenging environments. In this paper, an ultrasonic technique has been developed to examine the propagation of ultrasonic waves in the oil, water, and mixed oil-water liquids. The technique is expanded to determine the oil, emulsion, and water levels in an oil tank. A dedicated compact, low-cost, and programmable ultrasound-based Multi-layer level measurement (MLLM) device has been designed and implemented. The advantages of the new method over the current methods include contactless distance measurement, higher accuracy, lower cost, user friendly, simpler setup, and using non-nuclear rays. Additionally, the use of ultrasonic waves for the measurement has the advantage over light-based methods of being insensitive to dusty and smoky environment and almost independent of the object material and surface. Preliminary experiments have been conducted on the device. In this paper, the design and operating parameters of this device are discussed and evidence for the satisfactory performance is given. Key-Words: - Ultrasonic Device, Emulsion Level Detection, Oil Tank, Multi-layer Level Measurement 1. Introduction Oil producing institutions in many parts of the world are still faced with the problem of producing water and gas together with oil from their oil fields. Separating these three components from each other is a must. Such separation is usually done in stages. In one of these separation stages oil and water mixture is allowed to settle in large tanks for a short period of time. This process will cause the oil and water mixture to separate. However, the separation will consist of three components, oil at the top, oil/water mixture in the middle, and water at the bottom. Water will then be pumped out from the tank. However, in order not to pump out oil with water, the level of the mixed liquid (water-oil) need to be monitored continuously, especially during the pumping process. In [7] an extensive literature review on currently available level measurement methods, measuring devices and sensors has been investigated. The authors claimed that most of the devices have been designed to detect only the level of the top of the liquid in the tank. These measurement sensors include RF capacitance, conductance, nuclear, radar, differential pressure, optical switches, and ultrasonic. A microwave- based sensor is among the fewer devices which has been recently designed for extraction of the levels of the emulsion layers in the tank [1, 2, 3]. However the system is expensive. Additionally, the high energy of the microwaves makes the solution inappropriate for combustible liquids. In this paper, a new ultrasonic-based hardware device for MLLM is presented. The hardware design of both the ultrasound devices and the tanks as well as the placement of the sensors in the tank will be described. The property of the Ultrasonic transducer such as frequency and amplitude will