Water Journal : Water Journal September 2014
water SEPTEMBER 2014 42 Conference report screen filters (33μm and 90μm) were used as a primary treatment to characterise particles by size to see if removal of particles would have any negative impact on downstream biological nitrogen removal processes. Marginally higher COD reduction was noted in SBRs fed with fine-screened wastewater compared to the control bioreactors. No difference was recorded on the performance of bioreactors for nitrogen removal. Mostafa Zahmatkesh, from Delft University of Technology, The Netherlands, spoke on fungal pre-treatment of lignin-rich sludge. White rot fungi is one of the few organisms that can degrade lignin, and a pilot study using a bubble column bioreactor was undertaken. COD reduction of lignin-rich wastewater was found to improve significantly with inoculation by pre-grown fungal mycelium. Haibo Li, Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, China, spoke about Removal of Dissolved Organic Matter by Combining Anion Exchange and Cation Exchange Resins for Advanced Wastewater Treatment. He undertook full-scale trials on municipal and textile wastewater over a number of years. This study investigated and compared removal of dissolved organic matter from biological effluent by cation and anion exchange resins. Yongjun Zhang, TU Berlin, Chair of Environmental Process Engineering, Germany, delivered a presentation on his research into application of an aerated biofilter to remove trace pollutants. The study involved enhancement of naturally occurring manganese- oxidising bacteria to mediate the degradation of pollutants (as a tertiary stage) in WWTP effluent. Keynote speaker #5, Mitch Laginestra, GHD, Australia, spoke on applications of covered anaerobic lagoons in the red meat industry. Covered lagoons provide a number of benefits over conventional uncovered lagoons, including: • Opportunity to control odours; • Capture of greenhouse gases; • Use of biogas to generate electrical energy and thus minimise the carbon footprint of the facility. A number of design criteria including depth, cover type, gas removal, pre-treatment, gas cleaning, safety aspects, desludging, downstream treatment requirements and how to operate and maintain anaerobic lagoons were outlined. A number of case studies were presented, noting performance. Dr Jia-Qian Jiang, of the Glasgow Caledonian University, UK, then presented his research on modified adsorption chemicals for removal of heavy metals in water treatment. These were largely based on aluminium iron polymers. The final talk of the conference was delivered by Dr Santino Di Bernardino, of the Bioenergy Unit at Lisbon University, Portugal, on two-stage biological treatment of tannery wastewater. A bench scale system was set up using an anaerobic hybrid filter followed by anoxic sulphide oxidation reactor, converting H2S to elemental sulphur and recirculation loop (oxidation reactor mixed slurry is returned to the inflow). The theory provides for coexistence of methanogenic bacteria, sulphate-reducing bacteria and sulphur-oxidising bacteria converting hydrogen sulphide and sulphates into sulphur, minimising potential methane inhibition. This two-step treatment reportedly achieves higher removal of contaminants than conventional chemical precipitation, avoids the addition of chemicals, thus minimising sludge production, and removes hydrogen sulphide and sulphate. Other attractiOns The conference was scheduled to have a technical tour afterwards to Qingcaosha Reservoir, some 50km outside Shanghai on the famous Yangtze River. However, this was cancelled due to restrictions on access during the coincidental Economic Summit of Asia’s leaders (Vladimir Putin and leaders from 30 other Asian countries being in town). Shanghai is an interesting city, with a number of tourist attractions. The Bund (the river promenade) is a fascinating mix of old-world 19th century charm (built during the financial growth spurt of the city) on the western side, while on the eastern side of the Huang Pu River, the scale of construction and neon lights provides a spectacular backdrop. After Day 1, to showcase the spectacular eastern river front at night, an evening river cruise was arranged by the organising committee. Shanghai is reportedly China’s most expensive city. There are still plenty of great places to eat and go to, and the cost is not prohibitive, but if you go (for example) to the famous Long Bar of the Waldorf Hotel across the road from the Bund, a couple of small drinks cost close to $40 – a darn sight more than dinner for two at many restaurants. Certainly the transport rail network is very impressive (although patrons of the system need to learn how to queue), and the Huangpu River, old city, convention centre, People’s Park and French Quarter are all appealing. Dr Santino Di Berardino gave the final presentation on Day 2. Dr Di Berardino and Mitch Laginestra in front of the picturesque Tongji University in the bustling metropolis of Shanghai.
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