Water Journal : Water Journal May 2011
awa news regular features 34 MAY 2011 water National Water Week Ambassador Initiative AWA is looking for members to take part in the 2011 National Water Week Ambassador Initiative. Launched last year, the initiative aims to raise awareness of water issues among local communities. We estimate that over 6,000 young people were reached through the initiative in its first year. In 2011 we plan to grow this initiative, reaching more schools and young people during National Water Week. There are also plans to build on the educational resources provided to ambassadors and schools. In short, the National Water Week Ambassador Initiative will be bigger and better in 2011. Feedback from teachers and community group leaders suggest they really valued the initiative and welcomed the opportunity to have a water professional visit their school. If you are interested in becoming a National Water Week ambassador please go to the National Water Week website at: www.nationalwaterweek.org.au AWA Anaerobic Digestion Workshop Report This single day workshop, which took place 12 April 2011 in Sydney, is the first that AWA has organised in the Master Class format. The aim of this and subsequent workshops is to focus on different process improvement strategies, new and emerging technologies or new investigative tools that will improve the operation of core water and wastewater services delivered by AWA's members. In the past 10 years the focus of wastewater treatment has shifted to the recovery of resources from wastewater: water, energy and nutrients. Anaerobic digestion has recently become the preferred process as it produces biogas that could be used to heat the digesters to improve performance and reduce operating costs. It yields the following products: • Biogas, as green energy on its own or via co-generation of electricity. • Biosolids for beneficial use in various markets: agriculture, forestry, mine rehabilitation, compost and potentially energy production. The characteristics of biosolids product (such as stability, nutrients, odour emission, solids content, texture etc) determine the most suitable market. Many of the major utilities such as Sydney Water, SA Water and the Water Corporation in Western Australia have been conducting a series of optimisation projects to improve the performance of the existing digestion processes at their wastewater treatment plants to meet the challenge of this shift to resource recovery focus, particularly in regard to biogas. In addition, many of the major utilities have problem plants whose performance is lagging due to a variety of problems that differ with each facility. The Anaerobic Digestion Workshop heard from wastewater engineers at each of these utilities on their experiences in dealing with these challenges, while also hearing from academics researching specific aspects of the treatment processes with a goal to further improvements. Workshop Speakers Dr Paul Jensen from the Advanced Waste Management Centre (AWMC) at the University of Queensland looked at the process of assessing the efficiency of digestion processes at STPs. This involves relating the fraction of biologically degradable material removed in the process to the stability of the final biosolids product. Consideration is also given to the resources required to achieve this level of stabilisation in terms of capital (reactor volumes, supporting infrastructure) and energy usage. The biodegradability and bioavailability of organic sludges under anaerobic (and aerobic) conditions represents a benchmark for potential digester performance and can be represented by two key parameters -- degradability, or the percentage that can be effectively destroyed during digestion, and 1st order hydrolysis coefficient, or the speed at which material breaks down. Professor Paul Slatter, from RMIT University, took an even more basic approach by focusing on the flow properties of sludges. He began by defining rheology (from the Greek "rheos" -- flow -- and "logos" -- knowledge) as the science of flow phenomena. The eminent physicist Sir Isaac Newton postulated a direct proportionality relationship between the shear stress and shear rate in a fluid. The viscous characteristics of The NWW Ambassador Initiative helps raise community awareness.
Water Journal April 2011
Water Journal July 2011