Investigation of optimum condition to cultivate dry bacteria for wastewater treatment purpose
This project is aim to reduce the maintenance cost of biological wastewater treatment by reducing the interval of dry bacteria addition into the treatment system. The optimum condition to cultivate dry bacteria is first investigated. The condition will be tested for the stability of treatment system using raw food wastewate.
In most of the wastewater treatment plant, biological method is used to remove organic compound due to its cost effectiveness and high efficiency. For this purpose, mixed culture of bacteria with high efficiency in degrading organic compound is commonly utilised. Mixed culture in dried form is usually added to the aeration tank in wastewater treatment plant. To maintain the treatment efficiency, the dry bacteria needs to be added consistently into the aeration tank which incur extra cost for the treatment process. Hence, it is essential to investigate the stability of the treatment system while reducing the maintenance cost by reducing the interval of the addition of dry bacteria. For this purpose, the optimum condition such as dissolved oxygen, nutrients and pH for the cultivation of dry bacteria will first be investigated in this study by using synthetic wastewater of food industry. Response Surface Methodology will be applied by to investigate the optimum condition. After obtaining the optimum conditions, the removal efficiency of suspended solid (SS) and biodegradable oxygen demand (BOD) will be investigated by cultivating the dry bacteria in treating raw wastewater from food industry. The stability of wastewater treatment system by reducing the interval of dry bacteria addition can then be ascertained.