Water Journal : Water Journal December 2012
refereed paper asset management water DECEMBER 2012 89 Abstract Optimal corrosion and odour management has been hindered by limited understanding of several key in-sewer processes contributing to the problems, and the lack of tools and reliable technologies to support strategic decisions and cost-effective sewer operations. A major step forward to fill these gaps is being taken in Australia with a $21 million collaborative research project funded by the Australian Research Council (ARC) Linkage Program, 15 water industry partners and five university partners. The project is called the Sewer Corrosion & Odour Research (SCORe) Project. In this paper, the state-of-the-art knowledge and practice based on both published and grey literature is reviewed and key knowledge gaps and challenges to be addressed in the SCORe Project are identified. Some of the early findings from this initiative are presented. Introduction Sewer corrosion and odour problems are spread worldwide, particularly in countries with a warm climate. It is estimated that concrete sewer pipes in many areas of Australia are being corroded at an average rate of 1–3mm per year. Internal surveys by several major water utilities in Australia show that the abnormally fast depreciation of assets and the mitigation of corrosion and odour problems are costing the Australian water industry hundreds of millions of dollars a year. The operations of sewer systems are experiencing significant changes at present, posing further challenges to corrosion and odour management. Restricted water use in many areas caused by climate change results in considerably reduced flow within the sewer systems. This has resulted in more concentrated sewage and increased hydraulic retention time in sewers. Also, the changing demographics within major cities have caused concentration of commercial and industrial discharges in specific areas resulting in significant impacts on sewage characteristics. Control of corrosion at an acceptable rate and odour management require a good understanding of key in-sewer physical, chemical and biological processes to support strategic decision-making, and reliable tools and technologies to enable cost-effective sewer operations. The last comprehensive compilation of knowledge on odour and corrosion in sewers in Australia was prepared in 1989 under the title “Hydrogen Sulfide Control Manual” (MMWB, 1989) and is herein referred to in this paper as the “1989 H2S Manual”. Several key knowledge and technology gaps have been identified which hinder the optimal management of sewer corrosion and odour problems. These challenges should be addressed through the use of multi- and inter-disciplinary approaches that encompass material sciences, microbiology, chemistry, advanced instrumentation including sensor technologies, as well as mathematical modelling, among others. It is also essential to achieve effective integration of field investigations and laboratory studies. Strong partnerships and collaborations between researchers and industry are critically important for success. Integration of this knowledge with a strategic set of tools will be the key challenge to improve the management of sewer systems. In an effort to address these challenges most of the major water utilities in Australia are, along with the Australian Research Council (ARC), jointly funding a major project – the Sewer & Corrosion & Odour Research (SCORe) Project, which started in late 2008 and will run for five years with a total budget of around $21 million. The project comprises four themes, which are: • Theme 1 – Corrosion processes; • Theme 2 – Gas phase technologies; • Theme 3 – Liquid phase control; and • Theme 4 – Knowledge management. Nine inter-linked sub-projects (SP) have been designed under these themes; each has distinctive foci and is being undertaken by a dedicated research team that is located at one or more research centres around Australia. An overview of the project design is shown in Figure 1. The SCORe Project is approximately 80% complete but is progressively delivering outcomes for application by the Water Industry. Feedback is being provided to industry partners on a quarterly basis and a web portal (www. score.org.au) has been established to make this information readily available. R Rootsey, R Melchers, R Stuetz, J Keller, Z Yuan A review of published and grey literature and early findings and key knowledge gaps in the SCORe project TAKING CONTROL OF ODOURS AND CORROSION IN SEWERS Figure 1. An overview of the SCORe Project.
Water Journal February 2013
Water Journal November 2012-1