On-Site Sequencing 'Anaerobic-Anoxic-Aerobic/Biological' Process for Wastewater Reuse

The increasing scarcity of water around the world has become more evident at the beginning of this century. Management of this valuable resource is not only an environmental issue, it is also an important economic issue and its management has significant social implications. Moreover, the predicted decreases in annual rainfall around Australia, threatening the image of providing a sustainable water source for a majority of its population. The solution partly lies through the promotion of water conservation strategies involving wastewater recycling and reuse. A pilot scale 5-stage wastewater treatment system was investigated in regards to its feasibility for removing Biochemical Oxygen Demand (BOD5), Total Suspended Solids (TSS), Turbidity, Total Kjeldahl Nitrogen (TKN), Ammonia Nitrogen (NH3-N), Nitrate Nitrogen (N03-N), Organic Nitrogen (Org-N) and Total Phosphorus (TP) for the period of one year from Jan.2004 to Dec. 2004. The system readily reduced the concentration of BOD5 from average 189 mg/L to 5 mg/L (removal rate of 94%), TSS from average 216 mg/L to 3 mg/L (removal rate of 97%) and Turbidity from average 105 NTU to 2 NTU (removal rate of 96%). The removal rate for nitrogen and phosphorus was also quite satisfactory and this system was capable of reducing the Total Nitrogen (TN) from average of 41 mg/L to 5 mg/L (removal rate of 86%) and TP from average of 9 mg/L to 2 mg/L (removal rate of 81%).