Abstract:
The objective of this research is to study the design of wastewater treatment system for noodle and instant noodle factory by using biological treatment. There are 3 types of wastewater from noodle process, instant noodle process, toilet and canteen. The study was concerned with volume, suitable equipments and cycle time of treatment for two wastewater treatment designs which were preliminary physical treatment-anaerobic pond-Cyclic Activated Sludge System and preliminary physical treatment-equalization pond- Cyclic Activated Sludge System.The result obtained from the study show that the BOD5/COD ratio of wastewater is 0.72, therefore it could be treated by biological treatment. The reaction rate constant and the ultimate BOD loading were 0.1078 per day and 1,535 mg/l respectively that were used for calculation of cyclic activated sludge basin.From the result of study the optimum aeration time from 5 patterns of treatment, it was found that the treatment with F/M ratio in the range of 0.15 to 0.17 was suitable to reduce BOD, TKN and PO43- 97-99%, 85-99% and 37-53% respectively. The highest BOD, TKN and PO43- removal efficiencies were 98.85%, 97.28% and 52.34% respectively by 2-1 pattern {2-hour fill-aeration and 1-hour fill-settlement (repeat 3 times) and 1-hour decant}. The optimal condition for treated wastewater were 4-1 pattern {4-hours fill-aeration and 1-hour fill-settlement (repeat 2 times) and 1-hour decant} which was the lowest of the electrical consumption for operation and starting blowersand BOD, TKN and PO43- removal efficiencies were 98.74%, 84.71% and 47.92% respectively and the quality of treated water complied with the Ministry of Industrys effluent standard.