Removal of total coliform, e. Coli, uv254, particles, total dissolved solids (tds), suspended solids (ss), and colour using zeolite and activated carbon mixture in riverbank filtration
Perbandaran bersama dengan pertumbuhan pesat populasi manusia telah menyebabkan pencemaran air yang ketara. Pada tahun 2006, Jabatan Alam Sekitar (JAS) telah merekodkan sebanyak 18,956 punca-punca tetap yang merangkumi loji rawatan kumbahan (9,060: 47.79% termasuk 601 stesen rangkaian pam), industri pembuatan (8543: 45.07%), ladang ternakan (869: 4.58% ) dan industri berasaskan pertanian (484: 2.55%). Kualiti air sungai dan tasik yang buruk, banjir dan kekurangan air telah menjadi isu utama di Malaysia. Untuk menangani masalah tersebut, Malaysia telah mula menggunakan kaedah penapisan tebing sungai (RBF) untuk abstraksi air. Zeolit dan karbon teraktif diguna sebagai penjerap komposit mempunyai potensi untuk meningkatkan keberkesanan sistem RBF ini. Penyelidikan ini dijalankan untuk meninjau kemungkinan penggunaan kedua-dua bahan tesebut dalam sistem RBF. Ciri-ciri zeolit dan karbon teraktif ditentukan dahulu dengan menggunakan kaedah Imbasan Elektron Microskop (SEM) dan Sinar-X Pembelauan (XRF). Turus penapis direka bentuk menyerupai sistem RBF dan kadar penapisan yang sesuai ditetapkan. Prestasi penapis dalam penyingkiran zarah, jumlah koliform, E. coli, pepejal terlarut (TDS), pepejal terenap (SS), UV254 dan warna dikaji dengan menggunakan 2 susunan zeolit dan karbon aktif dengan saiz dari 1.18 mm ke 2.0 mm, iaitu 1) media bercampur dan 2) dua lapisan: zeolit (bawah) dan karbon aktif (atas). Berdasarkan keputusan SEM, zeolit yang digunakan terdiri daripada kristal bersaiz mikron dengan liang-liang kecil. Keputusan XRF menunjukkan bahawa zeolit yang digunakan berada dalam kumpulan Clinoptilolite dengan komponen utamanya SiO2 (79%) dan Al2O3 (13%). Bagi karbon aktif pula, keputusan SEM menunjukkan ia adalah sangat amorfus dan strukturnya berlapis-lapis dengan kehadiran rongga-rongga. Keputusan XRF bagi karbon teraktif menunjukkan komponen utamanya adalah C (93%) dan SiO2 (4%), dengan unsur-unsur surih (Fe, Zn dan Cu) sebagai pemangkin. Experimen penapisan pada kadar aliran 18.3 cm3/min dan masa tahanan 30 minit menunjukkan prestasi penyingkiran yang baik terhadap hampir semua parameter kecuali TDS dan zarah. Peratusan penyingkiran jumlah koliform dan E. coli adalah sangat baik iaitu masing-masing 95% dan 99%. Seterusnya, 67%-84% kekeruhan berjaya disingkirkan, diikuti warna (45%-70%) dan UV254 (20-47%). Zeolit dan karbon teraktif yang beralkali semula jadi menyebabkan peningkatan pH terhadap air yang telah ditapis. Turus A yang terdiri daripada campuran zeolit dan karbon aktif mempunyai prestasi yang lebih baik dalam pengurangan pepejal terampai, warna dan kekeruhan manakala bagi Turus B yang mempunyai dua lapisan, zeolite (bawah) dan karbon aktif (atas) mempunyai prestasi yang lebih baik dalam pengurangan jumlah koliform, E. coli, dan UV254. Liang-liang zeolit dan karbon aktif diperhati telah diisi oleh bahan pencemar selepas penapisan. Penyingkiran zarah dan jumlah pepejal terlarut (TDS) tidak dapat ditentukan kerana kesan larut resap ke dalam air.
_______________________________________________________________________________________________________
Urbanization together with the exponential growth of human population causes serious water pollution. In 2006, the Department of Environment (DOE) registered 18,956 water pollution point sources comprising mainly sewage treatment plants (9,060 : 47.79% inclusive of 601 Network Pump Stations), manufacturing industries (8,543 : 45.07%), animal farms (869 : 4.58%) and agro-based industries (484 : 2.55%). Poor water quality of rivers and lakes, flooding and water shortage have become major issues in Malaysia. To tackle the problem, Malaysia has started to use river bank filtration (RBF) for water abstraction. Zeolite and activated carbon as composite adsorbent has the potential to enhance the RBF system. Therefore, this study was investigated to look at possibility of using both materials in the RBF system. Both materials were first determined using scanning electron microscopy (SEM) and X-ray fluorescence method. The filter column that resembles RBF system was then designed. The filtration rate that are appropriate for RBF system was pre-determined. The removing performance of particles, total coliform, E. coli, total dissolved solids (TDS), suspended solids (SS), UV254 and colour was then determined at different configurations as follows: using different arrangements of zeolite and activated carbon with size from 1.18 mm to 2.0 mm, 1) mixed arrangement; 2) and two distinctive layers of zeolite (bottom) and activated carbon (top). The SEM results shown that the zeolite consists of micron-size crystal with small size of pores. Through XRF test, it can be concluded that the zeolite was from clinoptilolite group with main constituents of SiO2 (79%) and Al2O3 (13%). For activated carbon, SEM results show that it is highly amorphous and has layered-like structures with the presence of cavities. XRF tests for activated carbon shows that its main constituents are C (93%) and SiO2 (4%) with few transition elements (Fe, Zn and Cu) as catalyst within their compounds. Filtration experiments done at flow rate of 18.3 cm3/min and retention time of 30 minutes have shown good removal performance for almost all the parameters except TDS and particle sizes. Removal of total coliform and E. coli were excellent with 95% and 99% removal, respectively. It is then followed by 67% to 84% removal efficiency for turbidity, 45% to 70% for colour and 20% to 47% for UV254. Zeolite and activated which are alkaline in nature had caused the increase in pH of water after filtration. Column A which consists of a mixture of zeolite and activated carbon, performed better in removing suspended solids, colour and turbidity whereas for column B which has two distinctive layers of zeolite and activated carbon, performed better in removing total coliform, E. coli, and UV254. It has been observed that the pollutants filled up the pores of zeolite and activated carbon after filtration. However, concentration of particles and total dissolved solids (TDS) could not be determined due to leaching effect of zeolite and activated carbon into the water.
Removal of total coliform, e. Coli, uv254, particles, total dissolved solids (tds), suspended solids (ss), and colour using zeolite and activated carbon mixture in riverbank filtration
Removal of total coliform, e. Coli, uv254, particles, total dissolved solids (tds), suspended solids (ss), and colour using zeolite and activated carbon mixture in riverbank filtration / Lee Weoi Jye