Water & Wastewater Treatment

In the know Getting to grips with… hydrothermal oxidation further processed to recover valuable materials, such as phosphorus. As a net energy producer, AquaCritox has a positive impact on a WWTP's carbon footprint – and because it's a single-step, on-site treatment method, it also reduces truck movements between multiple treatment sites. Operating in a closed- loop process, issues surrounding odour and noise are avoided, and the route to disposal remains fully secure (as does the amount of energy that is generated). This gives WWTPs total control of the waste disposal process, as well as the costs involved. How much commercial interest has there been in the process so far? A-er almost 20 years of development, we're now seeing a surge of enquiries from across the waste treatment industry. There is strong interest from the oil and gas sector, where HTO can be used to safely dispose of spent caustic – a highly toxic waste produced during hydrocarbon processing. We are also noticing a shi- in attention to drinking water sludge treatment, where HTO has the potential to create a circular economy around coagulant recovery. At the moment, drinking water treatment plants are faced with heavy cost burdens to collect, transport and dispose of the sludge generated from the aluminium sulphate (alum) used as a coagulant in the treatment process (not to mention the loss of the alum itself). This also has significant ecological implications for WWTPs – so it makes both environmental and financial sense to recover and recycle the coagulant using HTO. 36 | APRIL 2015 | WWT | www.wwtonline.co.uk What is involved in the Eco- innovation project and what do you hope to achieve with it? We are privileged that the EU has selected AquaCritox as a key project to support within the Eco-innovation programme. The project will see the design, manufacture and installation of a volume AquaCritox demonstrator in Cork, Ireland (with an operating capacity of 15,000 tonnes per annum). This unit will carry out comprehensive testing of municipal and industrial sludges. It will then be shipped to a facility in the Middle East, where it will carry out further trials on several types of waste, including oil and gas waste. The aim of the project is to provide evidence of AquaCritox's significant financial and environmental benefits, and to clearly demonstrate its commercial feasibility – establishing a viable route to market for a range of applications. Extensive low-volume testing has already shown the huge potential for the technology, and by providing medium-volume results, the Eco- innovation project is the next step in realising this potential. It will also position the EU as a worldwide leader when it comes to the application of HTO, helping it meet environmental targets and boost economic growth. What are the next steps for the development of the technology? The Eco-innovation project will help secure AquaCritox's position as a commercially viable option for wet waste generators, processors and handlers in Europe and beyond. We've already seen a lot of interest in the project and its progress, and as well as raising the commercial profile of HTO, the results will form the final part of the official vendor qualification process for a number of parties. Beyond Eco-innovation, other ongoing projects across the globe are showcasing AquaCritox's capabilities internationally. Live trials at a working WWTP in Valencia, Spain will provide round-the-clock analysis of its treatment of sewage sludge, agri-food waste and industrial wet waste until 2016. The technology will also be used to generate energy from biosolids in the USA. These initial projects will act as an important launch pad for a technology that has the potential to change way we treat wet waste on a global scale.

• Cover