The 5th Barcelona Conference on MBRs – 28 May 2015
A report by J. Mata and J. Dosta, members of the organising committee
The 5th meeting of the biannual conference on Membrane Bioreactors (MBRs) was held on 28 May 2015 in Barcelona, Spain with a large number of participants. The event brought together a broad representation of key actors in the water treatment sector, especially those interested in the various aspects of the fundamentals and applications of membrane technology. This year, 15 papers distributed in 5 sessions were presented.
During the conference, it became clear that today aerobic MBRs are widely implemented. However, continuous improvements are taking place every day, such as those pointed out by technologists in their respective presentations, which unveiled the innovations developed over the last two years. MBR technology can pose challenges, especially in municipal applications, resulting from the economic situation, which makes its operation more difficult due to the relatively high energy costs despite efforts to diminish them.
But it should be kept in mind that in many cases, the situation would reverse if the excellent quality of the resulting water were otherwise taken into account. Therefore, there was a session devoted exclusively to the operation and cleaning of MBRs in aerobic sewage treatment plants (STPs), a classic topic that brought up the issue of the technical guide for the implementation of membrane bioreactors, recently published by CEDEX, the fruit of experience accumulated in recent years and presented at this event.
There was also a session, one of the longest, with four presentations, devoted to the topic of membrane processes in an anaerobic environment. The large number of papers submitted for presentations in this session pointed out the interest aroused by anaerobic MBRs (An-MBRs). Compared with the previous meeting which already addressed this issue, it was found that the interest in this technology has grown very significantly.
As was announced, an expanding technology such as forward osmosis was issued for the first time in this forum, with a round table at the end of the session, in which possible applications and their viability were discussed. This is a technology capable of treating solutions with a high osmotic pressure and reducing the fouling tendency of the membrane. Also, when there is no need to recover the osmotic solution, this technology results in an economical treatment. It was noted that a new generation of MBRs, osmotic MBRs, which do not require aeration, increases the possibility of eliminating fouling and helps the removal of emerging contaminants.
In the USA, forward osmosis is a technology that applies especially to the treatment of wastewater coming from hydraulic fracturing and to obtain drinking water from saline or polluted waters. However, it became clear that there is still some way to go before considering this technology as a mature one. It was also noted that the membranes play a crucial role in lowering costs and consequently it is necessary to reduce the cost of recovery of osmotic solutions.
The award of AquaEspaña 2015 was also delivered during the conference. This time, the recipient was Tomas Michel, General Manager of the network of technology centers Cetaqua and President of the European Water Platform (WssTP). He received this special mention in recognition of his career in the field of water treatment and control.
The afternoon sessions were mainly devoted to presentations from the industrial sector and other topics related to MBRs. Xylem presented the use of membrane systems to upgrade conventional STPs; Koch Membranes presented its new generation of pressurised hollow fibre membranes for tertiary treatments; Berghof explained the MBR-AnMBR together with direct filtration to optimise the energy costs, and Wehrle pointed out some relevant examples of MBRs combined with nanofiltration or reverse osmosis for treatment and reuse of wastewaters.
The last session was dedicated to two presentations: the removal of organic micropollutants in MBRs and the always-controversial direct use of treated water properly conditioned by multi-barrier systems, which gave rise to very interesting discussions.
In summary, all the presentations were very interesting, allowing the 5th meeting of this event to conclude as a success. Now the preparation for the 2017 meeting begins, although, on 25 November 2015, the organisers plan another interesting workshop on management and treatment of sewage sludge, which is expected to garner the interest of the sector again.