Measurement of Water Content of Petroleum by High Accuracy Interval Measuring Chip

At present, there are few high precision and inexpensive equipments for measuring the water content of petroleum (MMCP), which is a big problem faced by most of the operators. The sonic velocity is determined by the fluid property. So the different water content of crude oil will result in different propagation velocity of the sound. Hence we can take advantage of this property to detect the moisture of the crude oil. In this paper the theory of the water content detection by ultrasound is described, and the circuit diagram of the determination system is presented. The most advanced TDC-GP21 interval measuring chip produced by ACAM Company is adopted in this detection system, which can resolve the problem of the inconsistent temperature in the pipeline cooperated with the STC chip. This detection system is stable enough in the conditions of low flow rate, and it is economical to detect the water content of the crude oil. The detect error of this system is as low as 0.5%, which has been demonstrated by experiment.