Kebelakangan ini, mutu air di muara sungai Malaysia semakin menurun disebabkan oleh pembuangan bahan pencemaran ke dalam sungai. Kebanyakan bahan pencemar berasal dari air sisa domestik, agro-based kilang dan kilang pembuatan. Kajian telah dijalankan di Sungai Serai yang terpengaruhi oleh kuasa pasang surut di hilirnya. Terdapat sebuah kilang kelapa sawit terletak di hulu sungai di mana sisa air buangan dari kilang tersebut dilepaskan secara berterusan ke dalam sungai. Pepejal terampai (SS) merupakan parameter utama dipertimbangkan dalam kajian ini. Model yang digunakan untuk tujuan simulasi dikenali sebagai Water Quality Simulation Program (WASP7) and Dynamic Estuary Model Hydrodynamic Program (DYNHYD5). Kedua-dua model ini telah digabungkan untuk mensimulasikan kandungan pepejal terampai (SS) di sepanjang sungai dengan mengambil kira kesan pasang surut. WASP7 digunakan untuk mensimulasikan pepajal terampai yang disebabkan oleh sisa air kilang kelapa sawit (POME). Sementara itu, DYNDYH5 digunakan untuk mensimulasikan hidrodinamic sungai yang mengalami kesan pasang surut. Model seperti I1DISP dan E1DISP digunakan dalam kes ringkas untuk tujuan pengesahan WASP7 sebelum memulakan kerja simulasi yang sebenar. Kajian ini meneliti kesan jenis pasang surut, arus, kadar perlepasan air sisa dan lokasi pelepasan aii sisa yang menpengaruhi kandungan pepejal terampai di dalam sungai ini.
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Recently, the water quality of estuaries in Malaysia has degraded due to the discharge of pollutants into the estuaries. The pollutants mainly come from the wastewater of domestic sewage, agro-based industries and manufacturing industries. Sungai Serai in Johor is the river of study in this thesis. The river is subjected to two types of tides namely spring tide and neap tide. A palm oil mill is located at the upstream of the river where treated palm oil mill effluent (POME) is continuously released into the river. Suspended solid (SS) is the main water quality parameter considered in this study. In this study, models used in the simulation are known as Water Quality Simulation
Program (WASP7) and Dynamic Estuary Model Hydrodynamic Program (DYNHYD5). Both models were linked together to simulate the concentration of suspended solid in the river where the tidal flow was taken into consideration. WASP 7 was used to simulate the suspended solid in the river due to the discharge of treated POME. Meanwhile, DYNDYH5 was used to simulate the hydrodynamic regimes of Sungai Serai, which is subjected to tidal effect. In-house models such as I1DISP and E1DISP were used in simple case studies to initiate this study, and for the purpose of comparing with WASP7 results before the actual simulation work starts. The impacts of the types of tide, flow rates, loading rates of the treated POME and locations of the effluent discharge that govern the concentration of suspended solid in the river were discussed in this study.