NethWater consortium starts BOT (Build Operate Transfer) project

Since 2007, a volume of 5,000 m3 per day of WWTP (Waste Water Treatment Plant) effluent has been treated by NethWater partner Evides to produce demineralized water for reuse at the Dow Benelux plant in Terneuzen.
The WWTP will be extended with a new MBR (Membrane BioReactor) installation for effluent treatment with a capacity of max. 600 m3/h in 2009 in order to increase the re-use and to meet stricter effluent requirements.

Nethwater The project:
The WWTP Terneuzen (50,000 Pollution Equivalents), built in 1990, has undergone some important extensions over the years in order to meet stricter regulations. Since the beginning of the year 2007, a volume of 5000 m3 per day of effluent of the Terneuzen WWTP is the source for a dedicated water treatment plant to service Dow Benelux.

NethWater partner Evides Industry Water (EIW) owns and operates this "DECO plant" to supply various water qualities to the chemical plants of Dow Benelux at Terneuzen, the first plant in the Netherlands to reuse a combination of industrial and municipal wastewater on a large scale.

The Objectives:
The Terneuzen WWTP will be upgraded & integrated with an MBR system in the year 2009 for two reasons:
1. Investments in the Terneuzen WWTP for improvement of the effluent quality are foreseen in the near future.
2. The volume of reusing WWTP-effluent has to be doubled before 2010.

The new MBR system will have a nominal hydraulic capacity of 400 m3/hr and a maximal hydraulic capacity of 600 m3/h. The permeate water from the MBR is free of particles and will not be discharged to the environment, but fed to an RO membrane unit at DECO plant for further polishing and reuse as boiler feed water.

To increase the hydraulic load of the MBR the effluent of the existing conventional WWTP is fed to the MBRd. The feasibility of direct Ultra-Filtration (UF) treatment of the conventional effluent will be evaluated as an alternative.

Currently a MBR Airlift pilot system, supplied by NethWater partner NORIT, is in operation and is generating process data to serve the engineering for the full scale MBR plant. Objectives for the pilot scale research are determining the feasibility of different effluent supply schemes and the maximum and operational membrane flux through the MBR. Also the bio-fouling potential of both the MBR permeate and the conventional effluent has to be determined experimentally under different MBR operating conditions.

The first stage of the integrated membrane system (IMS) on DECO plant, the Netherlands The Technology:
Both the pilot and the full-scale installation are based on the Airlift MBR as developed by NethWater partner NORIT Membrane Technology. It is a side-stream system that had its first full-scale application treating the sewage of the town of Ootmarsum, The Netherlands. The fully automatic pilot installation has a nominal capacity of 3 m3/h (at 50 lmh). Iron(III) chloride is added to the MBR to lower the phosphate concentration in the permeate.