Water & Wastewater Treatment Magazine
Issue link: https://fhpublishing.uberflip.com/i/851629
10 | august 2017 | WWt | www.wwtonline.co.uk The Talk: Events I mproving physical factors in the sludge treatment process is the key to achieving intensification and getting more out of sludge treatment infrastruc- ture, delegates at the SludgeTech confer- ence heard. Giving a keynote address at the event held at Imperial College London, Dr Sudhir Murthy, Innovations Chief at DC Water, said that intensification and energy efficiency would be important consid- erations when designing and upgrad- ing treatment plants capable of serving mega-cities created by population growth, especially in Asia. "This is the decade of water," said Dr Murthy. "In the next two decades more wastewater treatment plants will be built and upgraded than at any time in the his- tory of mankind. It's a great opportunity and a great challenge." He spoke about DC Water's Blue Plains Physical factors vital for sludge intensification wastewater treatment plant in Washing- ton DC, a 1500 ML/day plant which has been serving the US capital since 1938. There is no scope for expanding the site, so the publicly-owned utility has focused instead in recent years on intensification, making the most out of its assets within the existing footprint. "We don't have any The UK's leading specialist pump hire company capable of up to 9800m³/hr and 20 bar pressures. Operating a 24/7 service worldwide, we sell, rent and maintain a wide selection of pumps and equipment, helping you to stay ahead of the curve. STAY AHEAD of the CURVE Call: 0800 707 6011 Visit: www.pioneerpump.com/emea BUY HIRE BUY or BUY 24/7 pp136-pioneer-pump-half-page-ad-v2.indd 1 15/06/2017 15:01 "In the next two decades more wastewater treatment plants will be built and upgraded than at any time in the history of mankind. It's a great opportunity," Dr Sudhir Murthy, Innovations Chief, DC Water more room, so we need to do more, with less, and in less space," he told delegates. The first priority was to improve the viscosity of sludge, which would then make the anaerobic digestion process more efficient. DC Water did this with the help of thermal hydrolysis technology from CAMBI which doubled the viscosity of the sludge going to the digesters from 10% to 20% on average. Centrifuge technology was used for the dewatering stage before the THP process, while a belt filter press was used for anaerobically digested solids. Both processes improved the physical qualities of the sludge and the centrifuge enabled phosphorus removal, by retaining the heaviest material. Since the introduction of these processes the utility has been able to sell biosolids as fertiliser under the brand name of 'Bloom'. Other improvements included the addition of a new flocculation tank a˜er a co-operative project with Thames Water. Overall, while intensification projects are generally required to achieve a 30% improvement in performance to make them viable, DC Water's process improve- ments achieved over 100% improvement, and in some cases more. Info: www.sludgetech.com James Brockett reports from London