Measurement system development of refractive index, salinity and magnetic field parameters on liquid waste polluted water

Abstract

A Prototype of liquid waste polluted water measurement system based on refractive index, salinity, and magnetic field parameters, has been developed. The instrument consists of Potentiometer, Light Dependent Resistor (LDR), conductivity sensor, Hall Effect sensor, and microcontroller. Potentiometer and LDR sensors are used to measure the refractive index, a conductivity sensor as the salinity measurement device, Hall Effect sensor as a magnetic field detector, and Arduino UNO as the control system. Each sensor has been characterized using a standard measuring instrument to determine sensor sensitivity. The characterization results showed that the refractive index sensor has a sensitivity of 321.8 mV/refractive index unit and a relative error of 0.35%. The conductivity sensor has a sensitivity of 415.2 mV/ppt and a relative error of 5.26%. The magnetic field sensor has a sensitivity of 0.0077 Volt/Gauss and a relative error of 4.29%. The prototype was used to measure the water quality of an artificial wastewater and river water samples. The artificial wastewater was made of the composite of water, salt, and liquid soap with different concentrations, and the river water samples were taken from ten different regions. The results show that the addition of salt and liquid soap concentration was directly proportional to the refractive index, salinity, and magnetic field. All samples have salinity below the normal threshold of <0.5 ppt.