Water Journal : Water Journal August 2014
AUGUST 2014 WATER 39 Conference Report DAY 2 On Day 2, NZ colleague Jacqui Horswell, whose contributions to the biosolids program regularly provide an insight into policies and concerns that are in focus for friends across the Tasman, delivered a paper titled Up the Pipe Solutions -- Can You Change What Goes Down Your Drain?. This work reported results from a community education program involving schoolchildren. Goals sought in this study were: I. to reduce the level of contaminants present in the municipal wastewater system ultimately ending in biosolids and where they came from II. to improve students' interest in science and initiate change in their behaviour when handling wastes. A comprehensive survey was designed with the help of a teacher. The students were required to take the survey home to identify products in their laundry, kitchen or bathroom that had ingredients they did not recognise or were concerned about, and to interview a parent or caregiver who was the primary household shopper about their motivations for purchasing household cleaning or personal care products. This tool was intended to stimulate students' awareness of household products and their contents. A video was developed to give grounding to the student survey. The lm provides a humorous but informative look at what goes down a household drain, what happens in an urban wastewater BIOSOLIDS WORKSHOP 2: BIOSOLIDS AND ENERGY OPPORTUNITIES Acknowledging the wastewater treatment plant as a resource recovery centre has become recognised overseas (UK and US) and increasingly in Australia. This workshop, facilitated by Diane Wiesner, began by looking at the initiative being taken at Yarra Valley Water to focus on using its anaerobic digester to turn organic food wastes into biogas and biosolids. In 2011, the utility rst looked at the opportunities for using STPs to produce renewable energy. Just over a year later, the design and construction of the plant began. The process begins with retrieval of the waste, pre-treatment and blending; then into the anaerobic digester, which yields biogas that is subsequently cleaned and stored for electricity generation. Davood Nattaghi followed with a UK perspective on biogas being used as a primary energy source for wastewater treatment. Aecom's Bill Barber, a keynote speaker from a previous Biosolids Specialty Conference, followed by talking about the most recent work on energy yield that can be achieved from different stages of the wastewater treatment process. Primary treated sludge in an anaerobic digester was shown to yield more gas than secondary-treated sludge, which in turn was better than tertiary-treated sludges. Carbon content in the sludges at various stages was judged to be the critical determinant. A lively open discussion then followed, framed around a series of questions and issues raised by the presentations. Damien Batstone from AWMC at UQ, whose key research focuses on resource recovery using anaerobic digestion, drew attention to the age of many digesters at Australian utilities as a key factor in their poor performance and relatively low levels of biogas produced. The Conference keynote speaker, Dr Sudhir Murthy, commented that in the US, particularly California, anaerobic digester gas production frequently exceeded plant needs and was fed into the electricity grid. Whether this would continue in the future in that state and others depended on its cost of production relative to other gas, including shale currently being available in US, as well as the fact that it is not an ideal substrate for producing electricity. WORKSHOP: CAPACITY BUILDING IN SOURCE MANAGEMENT This workshop ran over two sessions and was chaired by Ray Borg, Co-Chair of the Specialist Network. In the rst session, Adam Cunningham, David Greaves and Darshit Dalal from Barwon Water shared their experiences in developing the $94 million Northern Water Plant (NWP), a 7.5 ML/d reclamation plant, coupled with a 5 ML/d Class A advanced recycled water plant to supply the Shell Geelong Re nery. This potable substitution frees up approximately six per cent of Geelong's water demand and served as a case study for subsequent discussion. The second session provided an opportunity for delegates to explore the recent history of source and trade waste management, best practice current examples and current challenges. Some of the attendees at the Source Management session.
Water Journal September 2014
Water Journal June 2014