DIGITAL IMAGE PROCESSING AND ANALYSIS AS AN APPROACH TO THE DEVELOPMENT OF MEASUREMENT METHODS OF POLLUTANT CONCENTRATION ON SURFACE WATER DISSERTATION Written work is one of the requirements to obtain a doctoral degree from Institut Teknologi Bandung By RIJAL HAKIKI SID: 35319302 (Environmental Engineering Graduate Study Program) INSTITUT TEKNOLOGI BANDUNG 2024 i AUTHORIZATION PAGE DISSERTATION DIGITAL IMAGE PROCESSING AND ANALYSIS AS AN APPROACH TO THE DEVELOPMENT OF MEASUREMENT METHODS OF POLLUTANT CONCENTRATION ON SURFACE WATER It is true that it was written by myself and has never been made and submitted before, either in part or in whole, by others or me, whether at ITB or other educational institutions. Writer, Rijal Hakiki Student ID 35319302 Bandung, January 18, 2024 Chief Advisor (Prof. Barti Setiani Muntalif, Ph.D.) Program Chair Masters and Doctorate (Emenda S., S.T., M.T., M.Eng.Sc., Ph.D.) Advisory Member ( Ir. Yuniati MT, M.Sc., Ph.D. ) Advisory Member ( Irwan Purnama, M.Sc.Eng, Ph.D. ) ii ABSTRACT DIGITAL IMAGE PROCESSING AND ANALYSIS AS AN APPROACH TO THE DEVELOPMENT OF MEASUREMENT METHODS OF POLLUTANTS CONCENTRATION ON SURFACE WATER By Rijal Hakiki STUDENT ID: 35319302 (Doctoral Program in Environmental Engineering) Monitoring fluctuations in pollutant concentrations through regular measurement processes needs to be carried out in connection with the decline in surface water quality caused by the release of several pollutant loads originating from human activities. Total suspended solids (TSS), turbidity, and true color represent physical parameters that can be observed with the naked eye and can interfere with aesthetic and health aspects. Dissolved iron (Fe) and manganese (Mn) content affects the color of surface water and can cause health problems. The content of colloids, insoluble organics, microorganism cells, and microplastics was correlated with TSS concentration. The abundance of microplastics in waters can accumulate in aquatic organisms and can cause health problems for humans. Conventional measurement methods (gravimetry) and the use of electronic measurement instruments (turbidimeters, colorimeters, and spectrophotometers) are not free from errors and interference effects which can cause bias in measurement results. Measurements based on Digital Image Processing and Analysis Techniques (IPT) are an alternative method that can be developed to overcome errors and interference with edge detection approaches and color intensity quantification. This research is aimed at examining the mechanism of using a Light Isolation Chamber (BIC), assessing the performance of IPT-based TSS, turbidity, and abundance of primary microplastic measurement methods using an Edge detection approach, as well as methods for measuring true color, iron (Fe) and manganese (Mn ) based on IPT with a color intensity quantification approach. IPT-based measurements require a Light Isolation Chamber (BIC) to minimize ambient light interference with measurement results, which is the basis for developing BIC and examining various limiting factors for IPT-based measurements. The proposed method can be an alternative simplification method for measuring TSS concentration gravimetrically, measuring true color using the Nessler comparison/colorimetric/spectrophotometric method, as well as measuring the abundance of microplastics (specific for PP and PE microbeads) in surface water using thermoanalytical, density separation, FTIR and Raman spectroscopy became IPT based. In addition, the proposed approach can be an alternative method for simultaneous measurement of TSS concentration and iii turbidity level in one treatment, as well as sequential measurement of Fe and Mn concentrations with the application of specific reagent test kits. Furthermore, the proposed measurement method can anticipate interference with measurement results caused by the true color intensity of the solution and the TSS concentration in the water sample being measured. In its implementation, the research was carried out through various stages including testing the capabilities of IPT-based measurement methods, designing and fabricating BIC, determining limiting factors for IPT-based measurements, IPT-based measurements with an edge detection approach, and a color intensity quantification approach, as well as testing the performance of measurements based on IPT. The design of the BIC takes into account the results of the initial identification of method capabilities as well as the results of determining limiting factors as research control variables. Combinations of various concentrations of formazin suspension (HACH 246149), kaolin suspension (Sigma-Aldrich K7375), commercial microbeads (polyethylene and polypropylene), and surface water were used as standard series and as samples in edge detection-based measurements. Combinations of various concentrations of the Pt-Co color standard (HACH 141453), iron standard (Fe HACH 1417542), and manganese standard (Mn (NIST) HACH 1279142) and surface water are used as standard series and as samples in measurements based on color intensity quantification. The integration of a combination of limiting factors together with the Light Isolation Chamber (BIC) is a key factor in ensuring the consistency, validity, and reliability of the developed IPT-based measurement method. The edge detection approach was proven to consistently produce good repeatability and linearity in quantifying turbidity levels and TSS concentrations in artificial and surface water samples. Specifically for primary microplastic abundance parameters, it shows good performance on artificial samples, but still requires further development in its implementation in surface water, considering the limited abundance factors. The color intensity quantification approach has been proven to consistently produce good repeatability and linearity in quantifying iron, manganese concentrations, and true color intensity in artificial and surface water samples. Keywords: suspended solids, turbidity, iron, manganese, microplastic, image processing iv ABSTRAK PENGOLAHAN DAN ANALISIS CITRA DIGITAL SEBAGAI PENDEKATAN PENGEMBANG AN METODE PENGUKURAN KONSENTRASI POLUTAN P ADA AIR PERMUKAAN Oleh Rijal Hakiki NIM: 35319302 (Program Studi Doktor Teknik Lingkungan) Pemantauan fluktuasi konsentrasi zat pencemar melalui proses pengukuran secara berkala perlu dilakukan sehubungan dengan penurunan kualitas air permukaan yang disebabkan oleh pelepasan sejumlah beban pencemar yang berasal dari aktivitas manusia. Total padatan tersuspensi (TSS), kekeruhan dan warna sejati mewakili parameter fisik yang dapat teramati secara kasat mata sehingga dapat mengganggu aspek estetika dan kesehatan. Kandungan besi (Fe) dan mangan (Mn) terlarut mempengaruhi warna air permukaan dan dapat menyebabkan masalah kesehatan. Kandungan koloid, organik tak larut, sel mikroorganisme dan mikroplastik berkorelasi dengan konsentrasi TSS. Kelimpahan mikroplastik di perairan dapat terakumulasi pada organisme akuatik dan dapat menyebabkan permasalahan kesehatan bagi manusia.