MBR Varsseveld: 5 years of operational experience

Abstract

The Membrane Bio Reactor (MBR) in Varsseveld is the first full-scale plant in the Netherlands and functions as a demonstration plant for MBR technology. It has been in operation for 5 years and many lessons have been learnt in that time. To gain experience with this new type of treatment and to demonstrate that MBR is suitable for purification of domestic wastewater in a real situation a vast research programme was undertaken. Based on the operational experiences and the research program it can be concluded that the MBR Varsseveld shows promising results. Compared to conventional activated sludge systems with sand filtration (CAS-SF), the MBR produces superior effluent quality. Energy consumption remains up to 30% higher than the CAS-SF system but there is possibility for further improvements. The cleaning philosophy, that combines a regular maintenance cleaning with 2-yearly intensive cleanings, is effective at maintaining the membranes in optimal condition. Based on the experiences with the Zenon ZW500d membranes, a membrane lifetime of up to 10 years is expected.

Specific energy consumption of membrane bioreactor (MBR) for sewage treatment

“…The total specific energy consumption of the MBR could then be about 0.7 kWh/m'' and as such reach the set goals Van Bentem et al 2010). Nevertheless, as reported by Judd (2on), certain over aeration might be beneficial from an operational point of view.…”

“…For the next 3 years, energy consumption was slowly but steadily reduced. After 5 years of operational experience, further energy reduction is expected with a goal to reach 0.7 kWh/m'^ during normal MBR operation(Van Bentem et al 2010).…”

The optimal MBR configuration: Hybrid versus stand-alone — Comparison between three full-scale MBRs treating municipal wastewater

“…The specific energy consumption of the stand-alone MBR varied between 0.6-1.4 kWh/m 3 and was on average 0.84 kWh/m 3 , approximately 12% more than Hybrid #1 MBR during in series operation. However, after 5 years of operational experience with the stand-alone MBR further energy reduction is expected with a goal to reach 0.7 kWh/m 3 during normal MBR operation [37]. Figure 6 presents the energy consumption distribution of the MBR equipment for the hybrid MBR operated in series ( Figure 6a) and in parallel (Figure 6b) as well as for stand-alone MBR (Figure 6c).…”