Water & Wastewater Treatment

In Focus: renewable energy 6 WWT PUMP AND VALVE SUPPLEMENT 2019 mixing provides more consistency. It has a positive knock-on effect all the way through, including a big reduction in grit/silt, because it is plain to see from the increased gas yields that the digesters are being mixed properly. High volumes of grit Ten years ago in that Environment Agency Report (SC070010/R5), it stated that 'Conventional techniques prevail due to reliability and maturity of technology but the need for greater efficiency is driving novel technologies forward'. In 2020, how about: 'Conventional techniques should no longer prevail with old water industry anaerobic digesters because they contain ridiculously high volumes of grit and are therefore very inefficient indeed'. The chopper pump that powers our digester mixing system was invented back in 1950. It's all about horses for courses, so to take advantage of all that gas-rich sludge, it really is time to put the old nag out to pasture and retrofit in a digester mixing system that is fit for digesters at Minworth, it can be done. Taking legacy sludge directly from the dozen 5,000m 3 digesters, all the way back through to the hydrolysis plant (made by Cambi) saw our Landia pumps face an extremely arduous duty. From a process perspective, the chopper pump's continuous maceration is advantageous when tackling troublesome filamentous material – and as the sludge gradually improved, so did the efficiency of the pumps, with less rags meaning there was less energy required. Make no mistake, good mixing is critical. And as well as greatly improved gas yields, the additional benefits of externally-mounted mixing equipment are there to be gained, such as improved health and safety - eliminating the need for working at height, and confined space entry. With new-build such as at Murphy's installation for Yorkshire Water, there is a golden opportunity to get the mixing right first time, but working with an existing tank, a simple retrofit can take that digester up from its current 2 to 2.5% solids to 4% or greater - for an immediate pay off. 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 purpose. Be prepared though. 'Legacy sludge' – all that grit that has accumulated – is no job for any old pump – but just as MWH Treatment have proved for Severn Trent's upgrade of its 12 anaerobic The digester mixing system can be retrofitted on to steel tanks, or concrete.

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