MBR/IFAS reuse technology could be used at Chinese jewellery site

Two wastewater treatment plants being investigated for a new Chinese industrial park for precious-metal jewellery production could use advanced technologies for wastewater reuse.

Black & Veatch (B&V) and Zhongying Precious Metal Company Ltd (ZPMC), the park owners, are looking at technologies that would provide sustainable options for plants to treat domestic and industrial waste at the industrial park in the Lunggang District of Shenzhen.

ZPMC wants the plants to produce effluent that meets Chinese National Discharge Standard Class 1A, which will necessitate additional treatment to reduce nutrients and suspended solids. Class 1 is the standard required for wastewater being discharged into sensitive water bodies requiring discharge standards of BOD 10 mg/L, SS 10 mg/L, Total-P 0.5 mg/L and Total-N 15 mg/L.

The 12 ha industrial park will centralize design and production of precious-metal jewellery, which will help increase exports to international markets and also reduce pollution. The Shenzhen Government has been actively supporting the development of high tech industries in the area.

One park will treat domestic waste and have a capacity of 9,000 m³/d. The other will treat industrial waste with a capacity of 2,000 m³/d.

B&V will provide engineering design and equipment procurement services for the domestic wastewater treatment plant and civil and structural design for the industrial wastewater treatment plant. In addition the company will also provide specialist advice on the procurement, testing and commissioning of the plant.

B&V is investigating membrane bioreactor (MBR)/integrated fixed-film activated sludge (IFAS) technology. MBR/IFAS systems are well suited to some industrial and commercial applications and the high-quality effluent produced makes them a good solution for water reuse applications and for surface water discharge applications that require extensive nutrient removal.

MBR/IFAS technology can be designed for and operated in small spaces and has a high removal efficiency of nitrogen, phosphorous, bacteria, biological chemical oxygen demand and total suspended solids.

The project is expected to be completed by December 2010.