ICACT 2019
Permanent URI for this collectionhttp://repository.kln.ac.lk/handle/123456789/20316
Browse
4 results
Search Results
Item Soil Degradability of Food Wrapping Polythene Films Manufactured from PLA, PBAT and LDPE(4th International Conference on Advances in Computing and Technology (ICACT ‒ 2019), Faculty of Computing and Technology, University of Kelaniya, Sri Lanka, 2019) Abeywickrama, M.S.J.; Yatawara, M.D.M.D.W.M.M.K.Food wrapping polythene films manufactured from different virgin materials have become a major environmental concern at present as these films take much time for the complete degradation in the environment. This study assesses the soil degradability of films manufactured from poly-L-lactic acid (PLLA) (28%) + dimethyl ester (38%) + starch (26%) + auxiliaries (8%) (F001), poly-lactic acid (PLA) (F002), poly butylene adipate terephthalate (PBAT) (F003) and low-density polyethylene (LDPE) (F004) in natural soil. The tensile strength, elongation, moisture and water absorption of manufactured films were analyzed at the beginning of the experiment. Half of the manufactured films was immersed in food waste contaminated water and buried at 10 cm depth in soil. The other half was also buried without processing at the same depth in soil. The study was carried out for four months. Percentage degradability was calculated after 02- and 04-month intervals and by using weight losses as a representative parameter of the degradability. Results revealed the significantly highest tensile strength and elongation from manufactured F004. In addition, manufactured F004 showed the significantly lowest water absorption and moisture content (p < 0.05; ANOVA). Nevertheless, the highest percentage degradability (94%) in soil was observed from F003 followed by F002 contaminated with food waste. Moreover, the results showed a poor degradation (< 1%) of films manufactured from F004. The results further revealed that the films contaminated with foods degraded more than films those haven’t contaminated with foods. Therefore, the present study concludes that food wrapping polythene manufactured from PLA and PBAT showed a significant degradation potential within four months whereas films manufactured from LDPE did not show a remarkable degradation within the same time duration.Item Potential Use of Selected Macrophytes Based Constructed Wetlands for the Treatment of Landfill Leachate(4th International Conference on Advances in Computing and Technology (ICACT ‒ 2019), Faculty of Computing and Technology, University of Kelaniya, Sri Lanka, 2019) Perera, K.R.S.; Yatawara, M.D.M.D.W.M.M.K.Phytoremediation using constructed wetlands (CWs) is widely practiced for the removal of contaminants in landfill leachate. The present study was planned to assess the potential of floating macrophytes (Eichhornia crassipes and Pistia stratiotes) and emergent macrophytes (Typha angustifolia and Chrysopogon zizanioides) in improving the quality of leachate discharged from a Sequencing Batch Reactor (SBR) system located at Dompe sanitary landfill, Gampaha, Sri Lanka. The batch type CWs were arranged to identify the suitable dilution of leachate (as 0%, 25%, 50% and 75%) for the optimum plant growths. Based on the preliminary investigations, the potential of improving leachate quality by (ia) E. crassipes (T501) (ib) T. angustifolia (T502) and C. zizanioides (T503) at 50% dilutions and (ii) T. angustifolia (T04) and C. zizanioides (T05) at 0% dilution were assessed in continuous flow CWs. Water quality parameters including temperature, pH, electrical conductivity, turbidity, BOD, COD, TSS, phosphate, ammonium nitrogen, nitrate, sulphate and color were tested once in five days for 40 days period. Results were subjected to One-way ANOVA followed by Tukey’s pair wise tests in Minitab 14. Two sample t-test at 95% CI was also applied as required. With respect to controls, percentage reductions of measured parameters increased in wetlands having either floating macrophyte, E. crassipes or selected emergent macrophytes. Nevertheless, among the emergent plants, C. zizanioides [(T503) and (T05)] showed the highest performance in improving leachate quality followed by T. angustifolia [(T502) and (T04)]at both dilutions. Although E. crassipes (T501) showed higher percentage reductions of the selected parameters at 50% dilutions, this is not recommended as leachate dilutions are impractical in CWs. P. stratiotes has proven unsuccessful in the present study. Therefore, among the plant species selected, C. zizanioides that performed at 0% dilution could be recommended as the best plant for the remediation of leachate draining from SBR system.Item Use of Processed Tea Waste Powder and Fiber in Improving the Properties of Rice Husk Ash Filled Compressed Stabilized Earth Blocks(4th International Conference on Advances in Computing and Technology (ICACT ‒ 2019), Faculty of Computing and Technology, University of Kelaniya, Sri Lanka, 2019) Madhushani, K.L.; Yatawara, M.D.M.D.W.M.M.K.Rice husk ash (RHA) and processed tea waste (PTW) are major agricultural wastes. A recent study has shown that 7.5% of soil can be replaced with RHA in Compressed Stabilized Earth Blocks (CSEBs) due to its pozzolanic properties. Since PTW shows good pore-forming ability, the present study was planned to determine whether there is a potential to improve properties of previously upgraded CSEBs by replacing soil with PTW powder or fiber. The mixing percentage of soil, cement and RHA was 86.25: 6.25: 7.50 in the previously upgraded block. Five types of CSEBs of 300 mm x 150 mm x 100 mm (L x W x H)) were manufactured by replacing 0% (Control- BC), 3 %(B3), 5% (B5), 7% (B7) of soil by PTW powder and 3% (BF) of soil by PTW fiber. The suitability of properties of raw materials were tested prior to manufacture CSEBs. Mechanical properties of manufactured CSEBs were tested. Data were subjected to One-way ANOVA followed by Tukey’s pair wise comparison in MINITAB 14. The values were compared with SLS 1382: 2009 and British standards. The dry and bulk densities and weight reductions of PTW incorporated blocks (B3, B5, B7 and BF) showed significantly higher reductions (p <0.5) than that of Controls. B3 showed the highest compressive strength (3.8 Nmm-2) except Controls. In addition, B3 also showed the lowest surface erosion (pitting depth = 0 mm and pitting rate = 0 mm min-1) and the highest durability (Slake durability Index = 90). In addition, B3 showed the lowest loss on ignition (12.5%) and the percentage weight reduction (6%) except controls. According to SL standard 1382 part 1: 2009, only blocks BC and B3 were suitable for construction of walls (Grade 3). In addition, B3 was also suitable for external walls compared to control blocks. When compared with the British standards, only BC was suitable for load bearing walls for two storey houses. Considering all aspects, 3% of PTW powder incorporated CSEBs with 7.5% of RHA can be recommended for single story buildings and for external use in places where PTW is highly abundant.Item Reduction of Color, COD, and BOD5 of Treated Leachate Using an Activated Coconut Charcoal – Fired Clay Brick System(4th International Conference on Advances in Computing and Technology (ICACT ‒ 2019), Faculty of Computing and Technology, University of Kelaniya, Sri Lanka, 2019) Rajapaksha, N.M.; Yatawara, M.D.M.D.W.M.M.K.Removal of color from waste water by activated carbon is a common practice and studies have also been done with fired clay bricks. Nevertheless, no studies have been carried out to evaluate the removal of color by a combination of activated carbon (CC) and fired clay bricks (BR). The present study was therefore, planned to evaluate the potential of the combination of CC (activated by ZnCl2) and BR for the removal of color, chemical oxygen demand (COD) and five day biochemical oxygen demand (BOD5) of the treated leachate discharged from sanitary landfill located at Dompe, Gampaha,Sri Lanka. CC was impregnated with 0%, 5%, 10%, 15% and 20% ZnCl2 and activated in an oven at 2000C afterwards. The activated CC – BR systems were prepared in PVC pipes with the ratio of 1:0 (T1), 0:1 (T2-T6), 1:1(T7-T11), 1:3(T12-T16) and 3:1(T17-T21) BR particles and CC respectively. Leachate was filtered through the prepared systems at flow rate of 1L/hour. Color, COD, BOD5 and pH of filtrate were measured. Percentage reductions of parameters were first subjected to arcsine transformation and then to One-Way ANOVA in MINITAB 14. Tukey’s pair wise comparisons were also carried out to identify significant differences of parameters among different percentages of activated carbon. Results revealed that 20% ZnCl2 impregnated CC and BR at 1:0 system showed the highest percentage of color (>90%) and COD (>85%) reductions. CC - BR at 1: 1(CC activated by 20% ZnCl2) (T-11) and CC - BR at 3: 1(CC activated by 20% ZnCl2) (T-16) showed the highest percentage of BOD5 (more than 95%) reduction. After 5-hour filtration, 20% and 15% ZnCl2 impregnated CC and BR at 1:0 system showed pH lower than 6. The lowest pH was observed from 20% ZnCl2 impregnated CC. The study concludes that CC impregnated with high amount of ZnCl2 has a great potential to remove the color of leachate. Thus, the present study recommends the combination of 20% ZnCl2 impregnated CC: BR at 3:1 ratio as the most suitable combination for the removal of color, COD and BOD5 of the biologically treated leachate.