Measurement of fluid-specific conductance and pH in sewage pipe networks based on electrical resistance tomography

ABSTRACT Water quality parameter measurement has always been a hot issue in the field of industrial measurement as an important link in water environment governance. Recent studies on the measurement of specific conductance (SC) and pondus hydrogenii (pH) in sewage pipe networks have become increasingly mature. However, the limitations of existing methods, such as limited accuracy, poor stability, and the complexity of sensor preparation and operation, have restricted their application in actual working conditions. Electrical resistance tomography (ERT), a novel multi-phase flow measurement technology, has received widespread attention in the industrial measurement field due to its non-invasive, fast response, no radiation, and visualization features. This paper proposes a novel non-invasive SC and pH measurement method based on ERT, which is based on the principle of electromagnetic fields, and derives the linear relationship between SC and ERT boundary measurement values and the constitutive equation between the pH and ERT boundary measurement values based on the ionic SC characteristics of the solution. The method proposed in this paper is capable of detecting water quality parameters in a non-invasive manner that is more green, accurate, real-time, and sensitive, and offers a novel idea for non-invasive measurement of sewage pipe networks.