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EN
This study aimed to determine the performance of modified slow sand filter (SSF) media with blood clam shells (Anadara granosa) and activated carbon to remove turbidity, TSS, TDS, and FOG on the food court wastewater. The concentration of water pollutant parameters processed by SSF was determined based on Indonesia water quality standards, as well as knowing the optimum operational parameters of intermittent slow sand filter with Response Surface Methodology (RSM). The research data was processed using the Optimal type (custom) design which consisted of independent factors including the type of filter media, the addition of bacteria to the grease trap pre-treatment unit, and running time, as well as the research response in the form of the effectiveness of removing turbidity, TSS, TDS, and FOG. The reactor was operated intermittently (48 hours) for a maximum of 22 days and the concentration of pollutant parameters was calculated using the Standard Methods. The results of the Analysis of Variance (ANOVA, p<0.05) in the 2FI model of the study showed that there was a significant effect of all independent factors on the effectiveness of removing all water pollutant parameters. The most optimal operational parameters were achieved with the type of activated carbon media, the addition of Bacillus sp. in the grease trap pre-treatment unit in the amount of as much as 1%, and the detention time of 4 days, with the effectiveness of removing turbidity reaching 39.53%; TSS 45.25%; TDS 19.30%; FOG 61.35%.
EN
This research aimed to investigate the optimum conditions of slow sand filter (SSF) media modification by using ground Anadara granosa shell waste and the effect of the ripening period on the total coliform (TC) removal efficiency. The response surface methodology with the central composite design was conducted with three factors, namely, seeding time (2–3 weeks), running time (0–20 days), type of SSF media (i.e., river sand, A. granosa shell, and their combination), as independent variables. The results showed that the ripening period factor interacted insignificantly by improving the TC removal efficiency due to short ripening time (p > 0.05). The optimum conditions of the SSF to achieve maximum TC removal efficiency (99.70 ± 21.50%) were as follows: combination media of river sand and ground A. granosa shell waste, 2.8 weeks (20 days) of ripening period, and 20 days of operation. In conclusion, the optimum operating parameters of the slow sand filter revealed that the combination of river sand and A. granosa shell as well as prolonged ripening and running times could increase the removal efficiency of TC. Hence, the A. granosa shell has good application potential as filter media to remove TC from the municipal wastewater.
EN
This research aimed to discover the macroscopic, microscopic, and physiological characteristics and the genus of heterotrophic bacteria found in the schmutzdecke or biofilm layer in slow sand filters. The isolation of heterotrophic bacteria in the schmutzdecke applied the pour plate and quadrant streak method, while the characterization used macroscopic, microscopic, and physiological tests. Samples were taken from the schmutzdecke on top of the filter layer, and they were diluted 3, 4, and 5 times, then grown in Nutrient Agar media in order to isolate heterotrophic bacteria. The results of the research were analyzed using the identification manual books titled Bergey’s Manual of Determinative Bacteriology, 9th edition and Manual for The Identification of Medical Bacteria, 3rd edition. These manuals show the names of the genus of bacteria in the schmutzdecke layer. On the basis of the identification results from macroscopic, microscopic, and physiological tests, there were 4 dominant genera out of 18 living isolates obtained from the schmutzdecke layer, namely Kurthia gibsonii, Bacillus badius, Bacillus firmus, and Bacillus lentus. The similarity percentage of these 4 isolates was 83%, 81%, 85%, and 77% respectively.
EN
Bacterial co-metabolism in composting process has been widely used to remove hydrocarbons, aided by in-situ production of bio-based surfactants, in terms of compost humic acid-like substances and biosurfactants. The properties of compost humic acid-like substances have been shown in previous studies as potential surface tension reducers and emulsifiers for hydrocarbons. The current study aimed to analyze the properties of biosurfactant of surface tension decrease, emulsification activity, and hydrocarbon solubilization ability. Four indigenous bacteria consortia were isolated from composted materials of yard waste, rumen residue, crude oil-polluted soil, and the mixture of polluted soil with organic waste (1:1, w/w) at day 0th, 20th, 40th, and 60th. Organic waste consists of yard waste and rumen residue in the ratio of 1:1. The isolated indigenous bacteria consortia were incubated for 7 days in different media, i.e., organic waste extract, 6.00% of crude oil, and a mixture of organic waste extract with 6.00% crude oil. The results indicated that the surface tension decrease and emulsification activity of biosurfactants were 8.35–52.90 mN m-1 and 0.00–12.00%, respectively, which showed the potential as surface tension reducers with low emulsification activity. The higher hydrocarbon solubility was shown by the biosurfactant from the rumen residue (13 620 µg g-1) and the mixture (10 998 µg g-1) at day 40th, which was comparable to 1.50% of Tween 80. The biosurfactants in the current research were produced with the same materials, process, and time as compost humic acid-like substances which acts as in-situ bio-based surfactants. The respective ability to solubilize hydrocarbon might be combined and estimated to be higher than Tween 80 of 24 329 µg g-1 and 21 619 µg g-1 for rumen residue and the mixture, respectively. Therefore, it was concluded that the best composition for in-situ bio-based surfactant production to assist the degradation of hydrocarbon through composting process is polluted soil with organic waste (1:1, w/w). The solubility of hydrocarbons can be increased without synthetic surfactants addition, but through providing nutrients to maintain in-situ bio-based surfactant production with intermittent addition of organic waste every 40 days. This method is expected to be an appropriate approach in composting development as a cost-effective sustainable bioremediation technique for polluted soil.
EN
The presented study concerns on isolation and identification of indigenous bacteria in total petroleum hydrocarbon (TPH) polluted soil. The composite TPH polluted soil was collected from Wonocolo public oilfields, Indonesia. Pour plate and plate count techniques were used to bacterial population analysis and enumeration, respectively. Two dominant bacterial colonies were isolated from 4.06x107 CFU/g population in polluted soil, then morphologically and biochemically were characterized using Microbact Identification Kits (MicrobactTM GNB12A and 12B). The identification of isolated bacteria was performed using Bergey’s Manual of Determinative Bacteriology. The results showed that the strains of bacteria are Bacillus sp. and B. cereus with probability of 72.00 and 77.00%, respectively. These strains potentially acted as biosurfactant producers and hydrocarbon degraders. Thus, biostimulation could be implemented to reduce the TPH levels in polluted soil at Wonocolo public oilfields.
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