DESIGN OF A CAPACITIVE SENSING SYSTEM FOR MEASUREMENT OF WATER CONTENT IN CRUDE OIL

During crude oil exploration, transportation and refining process, the measurement of
water content is always a challenging widespread problem for researchers. Some
conventional measurement methods are researched in last decades but those methods
are laborious, less accurate and required special experimental preparations for a single
measurement. In this work, a capacitive sensing system for measurement of water
content in crude oil is presented. The proposed system is mainly divided into two
phases. In first phase, designing of capacitive sensor is performed for our particular
application of water content measurement in crude oil. The relation between water
concentration, sensor capacitance and output voltage is investigated in designing
phase of the capacitive sensor. In second phase, an interface circuit compatible to
designed capacitive sensor is proposed to detect capacitance changes in terms of
voltage variations. The theoretical analysis and simulation are performed with
dedicated software for each designing phase and validated with experimental
measurements.