Search

Domestic wastewater in Gampong Garot, Aceh Besar Regency, Aceh Province, Indonesia is directly discharged to the Daroy River without any treatment process. Domestic wastewater from Gampong Garot has been one of the contributors to microplastics contamination in the Daroy River. The microplastics (MPs) contained in domestic wastewater might come from used soaps and detergent products, as well as the scouring of clothes during washing. Thus, this study aims to investigate the abundance of MPs in domestic wastewater in Gampong Garot. The sampling points were determined based on purposive sampling, with samples taken at the end of the main pipe that directly leads to the Daroy River. Organics in domestic wastewater were removed using 30% H2O2 liquid through a digestion process at a temperature of 75°C. MPs characteristics such as size, shape, and colour were visually analysed using a light binocular microscope at 100x magnification, while the polymer type was analysed using Fourier transform infrared (FTIR) analysis. The concentration of MPs in domestic wastewater in Gampong Garot was 30.238 ±1.228 particles·(100 cm)-3 sample. The most common sizes of MPs were found to be in the range of 1,001-5,000 µm, while the dominant colour and shape were transparent and fibre-like. Polyester (PES) was the most detected type of MPs. These findings highlight the need for wastewater treatment before discharge into aquatic bodies. [ABSTRACT FROM AUTHOR]

Biomass is a central issue as new material that can be used as a substrate to produce biofuels, it has become global research to replace liquid fossil fuels with alternative renewable and sustainable fossils. Palm oil mill effluent (POME) is the potential of Agri-industrial waste to be used as alternative energy with anaerobic digestion of high concentration organic wastewater can be used for bioethanol production to replace food as raw material. Bioethanol can be produced in acidogenic steps in the organic degradation process. In this research, bacterial mixed cultures sourced from bovine rumen as biomass and the substrate used was palm oil mill effluent (POME) with a characteristic COD concentration of 25,600 mg/L, The operation of the reactor is set at pH 5; 6; 7 for 72 hours with the type of anaerobic circulating batch reactor (CBR), measurement of bioethanol products and acidogenesis of samples is carried out every 6 hours. The results showed that the reactor with variations in pH conditions 5 gave the highest efficiency of bioethanol formation in the 12 hour running process, result is 102,94 mg/L with a maximum formation rate of 9,98 mg/L/hour.

Bandung City is one of the big cities in Indonesia that grappled with waste problem. There is 1,500 ton of waste produced daily, of which 65% is organic. In addition, the water content of the waste could reach 80% during rainy season, given that the waste is commonly collected in open space before transported to the final disposal area. In order to tackle this issue, the municipality of Bandung has started to implement anaerobic digesters to treat kitchen waste since 2013 in an attempt to reduce organic waste. There are three scales of bio-digesters that have been implemented: city 2 ton, communal (20-1000 kg) and household scale (20 kg), which comprise of 1 unit, 15 units and 100 units respectively. This study evaluate the efficiency and biogas productivity of each bio-digesters type. We analyzed 30 unit and 14 unit of household and communal biodigesters respectively. The waste input, slurry output and biogas production were estimated based on average of daily basis. Both the input and output of the biodigesters were characterized (TS, VS, COD) to gain further understanding. This study provide facts and figures to improve the further implementation of household bio-digesters in Bandung City.

Ethanol is an alternative energy that can be considered to replace energy sources derived from fossils. Ethanol can be produced at the acidogenesis stage of the anaerobic conversion process of palm oil mill effluent wastewater. The efficiency of bioethanol formation is influenced by several factors, including the presence of micronutrients such as molybdenum and nickel. The purpose of this study was to determine the effect of the presence of molybdenum and nickel in the anaerobic wastewater treatment process on the formation of ethanol. Palm oil mill effluent was used as a substrate which was added with Mo with a concentration of 1 and 3 mg/L and Ni of 0.25 and 0.5 mg/L. Mixed culture bacteria as biomass was used in the reactor. CBR reactor is used with an operational time of 72 hours. The reactor performance was investigated by measuring ethanol production, volatile fatty acids, VSS, pH, and soluble COD. It was found that in the reactor with the addition of variations of Mo 3 mg/L and Ni of 0.25 mg/L ethanol production was higher than the other reactor about 578.44 mgCOD/L, while the higher COD removal occurs in the reactor with the addition of Mo and Ni variations of 1 mg/L and 0.25 mg/L respectively, which was 23.4%. These results show that the anaerobic product formation was influenced by the presence of molybdenum and nickel. [ABSTRACT FROM AUTHOR]

In this study, synthesis of TiO2 nanofiber-nanoparticle composite photocatalyst was carried out and its photocatalytic decolorization performance was investigated. TiO2 nanofibers were developed by electrospinning. The TiO2 nanoparticle films were prepared by dipping the glass substrates into a sol solution made by sol-gel method. The TiO2 nanofiber-nanoparticle composite was immobilized on glass plates and annealed at 500 °C. The effects of pH and catalyst loading were studied during a photocatalytic decolorization experiment using simulated dyeing wastewater containing Reactive Black 5 (RB5). The photocatalytic decolorization performance with 60 min of UV-irradiation time using the TiO2 nanofiber-nanoparticle composite was found to be higher (94.4%) than that of the TiO2 nanofibers (75.5%) and the TiO2 nanoparticle catalyst (74.1%). An alkaline condition and high catalyst loading were found to be preferable to achieve optimum photocatalytic decolorization of Reactive Black 5 (RB5). The TiO2 nanofiber-nanoparticle composite could be recovered after reusing multiple times through re-annealing at a high temperature. TiO2 nanofibers based on a composite catalyst that is strongly immobilized on glass plates enlarges the prospect of the photocatalytic method as a compact, practical and effective advanced treatment process for effluents from textile wastewater. [ABSTRACT FROM AUTHOR]