Environmental Engineering
E.N. Hidayah; R.B. Pachwarya; O.H. Cahyonugroho
Abstract
BACKGROUND AND OBJECTIVES: The existence of organic matter is one of the main issues for wastewater reclamation since chlorination is applied most frequently before use wastewater reclamation for many purposes. One of the eco-friendly and effective methods is using innovative material through resin immobilized ...
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BACKGROUND AND OBJECTIVES: The existence of organic matter is one of the main issues for wastewater reclamation since chlorination is applied most frequently before use wastewater reclamation for many purposes. One of the eco-friendly and effective methods is using innovative material through resin immobilized heterogeneous photocatalyst, which is based on the principle of advanced oxidation processes. Resin immobilized photocatalyst has been using for pollutant reduction, however lack of studies focused on dissolved effluent organic matter and its impact on the formation carcinogenic as by-product of water or wastewater treatment. This study aims to characterize organic matter by resin immobilized photocatalyzed titanium dioxide and zinc oxide and to determine its effectiveness in removing organic matter and potential for disinfection by-products in treated wastewater compare with resin only.METHODS: The bulk parameters, including total organic carbon, aromatic organic carbon as ultraviolet at 254 nm wavelength and specific ultraviolet absorbance value, and disinfection by-products formation potential, including trihalomethanes and haloacetic acids concentration was measured.FINDINGS: The results present that all materials could remove organic carbon in the range 58.18% - 93.45%, aromatic organic carbon removal 48.77% - 76.51%, and specific ultraviolet absorbance value decreased into less than 2 L/mg-m after longer contact time. Disinfection by-products formation potential concentration removal decreased and indicated the consistency results with bulk parameters removal. Resin immobilized photocatalyzed zinc oxide performed a higher efficiency removal than resin immobilized photocatalyzed titanium dioxide and resin only.CONCLUSION: This study exhibited the performance of resin immobilized photocatalyst with titanium dioxide and zinc oxide in removing dissolved organic matter and to control the formation of disinfection by-products. A combination between bulk parameters and disinfection by-products formation potential removal concluded that the aromatic structure, was mainly haloacetic acids precursors, while the non-aromatic organic fraction was probably trihalomethanes precursors.
Environmental Management
O. H. Cahyonugroho; S. Hariyanto; G. Supriyanto
Abstract
BACKGROUND AND OBJECTIVES: Dissolved organic matter has a fundamental role in supporting phytoplankton abundance and growth in aquatic environments. However, these organisms produce dissolved organic matter with varied quantities or characteristics depending on the nutrient availability and the species ...
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BACKGROUND AND OBJECTIVES: Dissolved organic matter has a fundamental role in supporting phytoplankton abundance and growth in aquatic environments. However, these organisms produce dissolved organic matter with varied quantities or characteristics depending on the nutrient availability and the species composition. Therefore, this study aims to assess the characteristic of dissolved organic matter on surface water and its correlation with phytoplankton abundance for monitoring water quality.METHODS: The sample was obtained at four Kali Surabaya River stations for further dissolved organic matter analysis and phytoplankton species analysis. The analysis was presented through bulk parameters of total organic, ultraviolet at 254 nm wavelength (UV254), specific ultraviolet absorbance value, and fluorescence spectroscopy using excitation-emission matrices with fluorescence regional integration analysis.FINDINGS: The results showed the bulk parameters of dissolved organic matter at all stations were significantly different, as Station 1 and 2 were higher, while 3 and 4 had a lower concentration. Furthermore, the fluorescence spectroscopy identified four components of dissolved organic matter at all stations, namely aromatic proteins-like (AP-like), humic acid-like (HA-like), soluble microbial by-products-like (SMPs-like), and fulvic acid-like (FA-like). Also, stations 1 and 2 were grouped in the high percentage FRI of humic substance (FA-like and HA-like), while 3 and 4 were classified in the high percentage FRI of non-humic substances (AP-like and SMPs-like).CONCLUSION: The main phytoplankton species, namely Plectonema sp., Pinularia sp., Nitzchia sp., Navicula sp., had the highest abundance at Stations 1, 3, and 4, respectively. A strong correlation between dissolved organic matter analysis and phytoplankton abundance led to the usage of these methods for monitoring surface water quality.
