Project background and origin
Fengshanxi Sewage Treatment Plant (renamed as Fengshan Water Resources Center) was running on September 7, 2005. It covered an area about 10 hectares and treated with secondary activated sludge biological treatment method. In the first phase, the design average sewage volume was 109,600 CMD. The actual sewage treatment volume was about 32,000 CMD in 2011, and about 10,000 CMD was from the interception collection. The water quality of effluent was better the discharge water standard (COD ≦ 100 mg/L, SS ≦ 30 mg/L and BOD ≦ 30 mg/L), and both the water volume and the water quality have the development potential of water recycling.
Kaohsiung is a high-risk of water supply area, and companies in the Linhai Industrial Zone have expressed their willingness to use reclaimed water, so plans for water recycling and utilization are proposed, and make preliminary engineering planning.
Major events of Fengshan Water Resources Center
The major events of the Fengshan Water Resources Center are shown in Fig. 1.
Planning outcome
- Location of the reclaimed water plant: The reclaimed water plant site can be assessed in three ways. It will be set up in the sewage treatment plant area, the client (Linhai Industrial Zone) and the water distribution route relay area. After comparing the advantages and disadvantages, it will be set at the reclaimed water plant.
- The planning process of the reclaimed water plant: Based on the designed water production capacity of 45,000 CMD, the reclaimed water treatment process is recommended: discharge water (before chlorination) → pre-filtration → Ultrafiltration → Reverse Osmosis → disinfection (chlorination) → reclaimed water. It assumes that the water production rate/recovery rate of UF and RO equipment is 90% and 60%, and the whole plant water production rate is about 54%.(see Fig. 2)
- Water distribution pipeline route planning: After detailed analysis, select three water distribution routes to Linhai Industrial Zone. The water distribution capacity is 45,000 CMD, which is planned along the two ends of the Xiaogang Airport and the Fengshan River bank. The cube diameter is 800 Millimeter, and Material is HDPE tube.
- Estimation of project cost: The project mainly includes reclaimed water plant project (pretreatment, UF, RO, filtered backwash and RO concentrated drainage treatment facility), water distribution pipeline project (pipeline engineering, distribution reservoir and pump station) and Augmented interception project, the total project cost is about 2.63 billion TWD, and the cost of amortized water plant and pipeline is about 13.7 TWD / ton. If take operating cost(12.0 TWD / ton) into consideration, the total cost per unit of water production is 25.7 TWD / ton.