Pelepasan kumbahan kilang kelapa sawit (POME) tanpa rawatan akan mencemar alam sekitar. POME akan dirawat dalam pencernaan anaerobik sebelum pelepasan. Acidogenesis merupakan fasa kedua dalam pencernaan anaerobik dan akan menghasil asid organik (VFA). VFA akan digunakan oleh mikroorganisma untuk menghasilkan polyhydroxyalkanoate (PHA), plastik biodegradasi. Terdapat banyak faktor yang mempengaruhi penghasilan VFA (acidogenesiss) oleh mikroorganisma seperti masa penahanan hidraulik (HRT), masa penahanan pepejal (SRT), suhu operasi, pH dan nutrien yang diperlukan oleh mikroorganisma. Kesan kepekatan nitrogen ammonia (300 mg/L, 400 mg/L dan 500 mg/L) dalam penghasilan VFAs oleh mikroorganisma untuk merawat POME telah dikaji dalam kajian ini. Prestasi acidogenesis akan berdasarkan penghasilan VFA yang termasuk asid asetik, asid propionik, asid butirik, asid valerik, asid caproik dan asid heptanoik. Keputusan menunjukkan bahawa nitrogen ammonia telah merangsang aktiviti mikroorganisma. Kepekatan nitrogen ammonia 500 mg/L mempunyai penghasilan VFA yang tertinggi diikuti dengan kepekatan nitrogen ammonia 400 mg/L dan 300 mg/L. Walau bagaimanapun, kepekatan nitrogen ammonia tidak akan menjejaskan pepejal mudah meruap terampai (MLVSS) iaitu bilangan mikroorganisma, permintaan oksigen kimia (COD) dan kepekatan nitrogen dalam kumbahan kilang kelapa sawit.
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Palm oil mill effluent (POME), the wastewater from palm oil mill industry is harmful to environment if discharge without treatment. Thus, POME is usually treated in anaerobic treatment system before discharge. Acidogenesis, the second stage of anaerobic treatment will produce volatile fatty acids (VFA). VFAs are consumed by microorganism to produce polyhydroxyalkanoate (PHA), biodegradable plastic. There are many factors to affect VFAs production (acidogenesiss) and PHA consumption by microorganism such as hydraulic retention time (HRT), solid retention time (SRT), temperature, pH and nutrient required by microorganism. In this study, the effect of concentration of ammoniacal nitrogen with the range of 300 mg/L, 400 mg/L and 500 mg/L on the VFAs production by microorganism treating POME was studied. Performance of acidogenesis was based on the production of VFAs which include acetic acid, propionic acid, butyric acid, valeric acid, caproic acid and heptanoic acid. Results showed that ammoniacal nitrogen able to stimulate the activity of microorganism. 500 mg/L of ammoniacal nitrogen had the highest concentration of VFAs produced followed by 400 mg/L of ammoniacal nitrogen and 300 mg/L of ammoniacal nitrogen. However, ammoniacal nitrogen did not significantly affect amount of microorganism, chemical oxygen demand (COD) and nitrogen concentration in POME.
Effect of ammoniacal nitrogen on production of volatile fatty acid in anaerobic treatment of palm oil mill effluent (pome) / Ku Kit Ting