Urbanisasi dan perindustrian telah menyebabkan pencemaran air yang teruk terutamanya kepada badan air yang bertindak sebagai sumber bekalan air. Disebabkan oleh pengurangan sumber air bersih dan peningkatan pencemaran meningkat yang pesat, sistem penapisan tebing sungai yang menggunakan proses penapisan semulajadi boleh dilaksanakan sebagai kaedah rawatan awal. Zeliac merupakan bahan penjerap komposit, mempunyai potensi untuk mengubahsuai sistem penapisan tebing sungai. Oleh itu, kajian ini dijalankan untuk mencari potensi Zeliac dalam sistem penapisan tebing sungai dengan menentukan julat saiz zarah dikekalkan/diserap dan memeriksa prestasi Zeliac dalam penyingkiran jumlah koliform, E. coli, jumlah pepejal larut, pepejal terampai, UV254 dan warna semasa proses penapisan. Tiga saiz Zeliac, 1.18 mm - 2 mm, 0.425 mm - 0.6 mm dan 0.15 mm - 0,212 mm telah dibandingkan. Ciri-ciri air sungai telah dikaji sebelum proses penapisan. Seterusnya, proses penapisan dijalankan selama 15 hari. Hasil kajian menunjukkan bahawa saiz zarah dan jumlah pepejal larut dikekalkan/diserap oleh Zeliac tidak dapat ditentukan kerana larut lesap Zeliac. Penyingkiran jumlah koliform, E. coli, pepejal terampai, UV254 dan warna adalah baik dan tidak mencapai kehausan dalam 15 hari. Zeliac telah menyebabkan peningkatan pH kepada air yang mengalir melaluinya. Zeliac dengan saiz 1.18 mm-2 mm, 0.425 mm-0.6 mm dan 0.15 mm-0.212 mm menunjukkan perbezaan yang tidak signifikan dalam penyingkiran jumlah koliform, E. coli, UV254 dan warna manakala penyingkiran pepejal terampai dengan saiz 0.425 mm-0.6 mm mempunyai kecekapan yang lebih tinggi daripada saiz 1.18 mm-2 mm. Zeliac dengan saiz 1.18 mm-2 mm telah meningkatkan pH air yang paling banyak, 0.9% lebih daripada saiz 0.425 mm-0.6 mm dan 1.1% lebih daripada saiz 0.15 mm-0.212 mm. Ujian desorpsi menunjukkan bahawa Zeliac dengan saiz 1.18 mm-2 mm paling terdedah kepada larut lesap, diikuti dengan saiz 0.425 mm-0.6 mm dan 0.15 mm-0.212 mm.
_______________________________________________________________________________________________________
Urbanisation and industrialisation have caused severe water pollution especially to water bodies which act as water supply source. With water quality problems occur due to various factors, riverbank filtration (RBF) which utilises natural attenuation processes can be implemented as a low cost pretreatment method. Zeliac, which is a composite adsorbent has the potential to modify RBF system. Therefore, this study was carried out to determine its potential in RBF system by determining the range of sizes of the particles retained/adsorbed and to characterize and examine the removing performance of total coliform, E. coli, total dissolved solids (TDS), suspended solids (SS), UV254 and colour by Zeliac during filtration process. Three sizes of Zeliac, 1.18 mm – 2 mm, 0.425 mm – 0.6 mm and 0.15 mm – 0.212 mm were used to compare their removing efficiency of selected parameters. River water characterisation was carried out before column study. The column study was then conducted for 15 days. The results showed that the range of particle size and total dissolved solids (TDS) retained/adsorbed by Zeliac cannot be determined due to leaching of Zeliac. The removal of total coliform, E. coli, suspended solids (SS), UV254 and colour are good and not achieve breakthrough in 15 days. Zeliac has caused the increase of pH of the water flowing through it. Zeliac with sizes 1.18 mm – 2 mm, 0.425 mm – 0.6 mm and 0.15 mm – 0.212 mm show no significant difference in removal efficiency of total coliform, E. coli, UV254 and colour while the removal of suspended solids (SS) by Zeliac with size 0.425 mm – 0.6 mm has higher efficiency than Zeliac with size 1.18 mm – 2 mm. Zeliac with size 1.18 mm – 2 mm has increased the pH of water the most, which is 0.9% more than size 0.425 mm – 0.6 mm and 1.1% more than size 0.15 mm – 0.212 mm respectively. Desorption test showed that Zeliac with size 1.18 mm – 2 mm is the most prone to leaching, followed by size 0.425 mm – 0.6 mm and 0.15 mm – 0.212 mm respectively.
Removal of selected river pollutants using zeliac filter in riverbank filtration / Cheong Kah Win