Analysis of multimedia filter effectiveness to improve the quality of rainwater runoff in fulfilling urban raw water supply

AbstractRainwater is recommended as a clean water supply through several water treatment methods. Based on preliminary data test results, several parameters exceed the sanitary hygiene water standard. This research aimed to improve the quality of rainwater runoff using the multimedia filter, which combined filtering and physical adsorption process. The combination of silica sand, activated carbon, and zeolite media was simulated into a pilot-scale of 1:2 reactor. Based on the first experimental results, the use of proposed media has a significant effect (p-value≅0) on several parameters. The best improvement in effluent quality reaches 100% in nitrites removal, 29% in nitrates removal, and 94.4% in total coliform removal. However, the media thickness variation factor has an insignificant effect (p-value 0.616) to effluent quality. Based on the second experiment results, hydraulic loading rate (HLR) variation shown a significant effect (p-value 0.01) on several parameters. Effluent quality improvement reaches 71.4% in nitrites removal, 100% in nitrates removal, and 91.9% in total coliform removal. However, variation in HLR gave an insignificant effect (p-value 0.769) on improving effluent quality.</jats:p

The effect of roof surface area on the quality and quantity of rainwater runoff in the rainwater harvesting system

Abstract Rainwater harvesting system is one of the alternative sources of clean water supply to be used during the dry season. The purpose of this research was to analyze the effect of roof area on the quality and quantity of rainwater runoff and determine the potential of rainwater runoff based on quality standards. The observation was conducted 2 different times and collected 23 samples of rainwater runoff from 11 different roof areas. Daily rainfall intensity data during the observation period were analyzed to estimate the quantity of rainwater runoff discharges from the rooftop catchment area. The results showed that parameters that meet the clean water quality standard are turbidity, iron, manganese, nitrate, and nitrite in both observation time. While the color, pH, TDS, and E. coli exceeds the clean water quality standard. The highest rainwater runoff volume was 20.59 m3 for the first week and the second week was 14.06 m3. In conclusion, the rooftop catchment area significantly affects the quantity and quality of rainwater runoff, and potentially be used as a clean water supply through a simple water treatment unit.</jats:p

Impacts of zeolite activation temperature and grain size toward bioretention system efficiency in removing Pb and Zn pollutant in stormwater runoff

Abstract Stormwater runoff can be utilized as a clean water supply through a simple treatment technology such as a bioretention system. However, this water treatment efficiency is influenced by various factors. Previous research showed that although the bioretention system had combined with a plant and media composition, effluent concentration still exceeds the quality standard. This research aimed to improve the bioretention efficiency in removing heavy metal Pb and Zn in stormwater runoff. Three variations of bioretention were prepared, with the same combination of 2 types of plants (Chrysopogon zizanioides and Iris pseudacorus) and media composition (zeolite: quartz: compost: soil = 6:2:1:1). The zeolite activation temperatures and grain sizes simulated with three discharges variation of initial Pb and Zn concentration of synthetic stormwater runoff. The results showed that modified bioretention produced higher Pb removal efficiency (99.95% on average) and Zn (98.89% on average). Besides, the effluent concentrations have met the water quality standard following Government regulation No. 82/2001. In conclusion, the higher temperature of activated zeolite combined with smaller grain size significantly enhance the removal efficiency of Pb and Zn in stormwater runoff.</jats:p

Aluminium Recovery from Water Treatment Sludge as Coagulant by Acidification

Abstract Aluminium in water treatment sludge can be recovered as coagulants by acidification method. However, there are some factors that affect efficiency in recovering aluminium, such as stirring speed during acidification, pH, and sludge characteristic. This study aims to find the optimum acidification stirring speed in recovering alum and to evaluate the performance of recovered coagulant compared to a pure coagulant. Aluminium recovery is carried out by adding sulphuric acid until the pH of the sludge reaches 2.5. The acidic sludge is stirred for 30 minutes, with acidification stirring speed is varied from 240–720 rpm, and left for settling until the supernatant is formed. The supernatant was used as a recovered coagulant, examined using a jar test to determine the optimum dose, and compared with the pure coagulant. The results show that the optimum acidification stirring speed was obtained at 540 rpm, where mass balance shows aluminium recovery efficiency of 16.5%. The optimum dose for recovered coagulant was 25 ppm, with a turbidity reduction of 93.38% in jar test. While the optimum dose for pure alum was 20 ppm, with turbidity reduction of 93.26%. Though potentially reduced higher turbidity, the recovered coagulant has slightly lower quality than the pure coagulant, which required a higher optimum dose.</jats:p

The analysis of groundwater quality around a material (solid waste) recovery facility (a case study of the Merdeka 2 material recovery facility in Depok, West Java)

Abstract Merdeka 2 Material Recovery Facility (MRF) is an organic waste management facility located in West Java. MRF also produces leachate water which came from organic waste that could potentially pollute shallow groundwater around the facility. Purpose of this study is to obtain knowledge regarding amount of MRF’s waste intake and composition, composition of leachate water that came from the waste, and the groundwater quality around MRF with parameters including pH, temperature, BOD, COD, Nitrite, Nitrate, Ammonia, KMnO4, Iron (Fe), and Fecal Coliform. Quality of the groundwater was analysed by knowing pollution rate based on pollution index and its association with distance variation from MRF. Results showed that amount waste that came to the facility is 0.954 ton/day with an average of waste volume 1449.20 l/day and consists of 93.4% organic waste and 6.4% non-organic waste. For MRF’s leachate water quality showed that pH, temperature, BOD and COD parameters exceeded over required standard. Shallow groundwater around MRF showed that average rate of pH, BOD, COD, Nitrate parameters is still above required standard and other parameters average is still in required standard and there is no significant correlation between distance variation with the groundwater. It can be concluded that the pollution index of the local’s shallow groundwater fall into low to mid polluted category.</jats:p

Enhancing removal efficiency of heavy metals and ammonia in bioretention system using quartz sand and zeolite as filter media

Abstract Bioretention is one of the stormwater runoff managements to reduce pollutant concentration such as heavy metals and ammonia. However, removal efficiency of bioretention was affected by variation of filter media. So, the aims of this study are to enhance removal efficiency of bioretention system. Three bioretention system were applied on pilot scale sized 30 × 30 × 80 cm3 combined with Iris pseudacorus. Variation of filter media composition of quartz sand and zeolite was used with ratio 1:3, 1:1, 3:1, on reactor 1, 2 and 3, respectively. Synthetic runoff water with different concentration were simulated. The results shown that variations in influent concentrations has small effect on the removal efficiency (20-40%). The average removal efficiency of bioretention 1, 2 and 3 for Pb was 91%, 78%, 83%, respectively, followed 88%, 95%, 94% for Zn and 97%, 98%, 96% for NH3. The combination of quartz sand and zeolite as filter media significantly enhance removal efficiency by 11,5% for NH3, 18% Pb and 20% Zn compared to previous similar research.</jats:p