Water Recycling
Innovative technology allows for economical recycling of aquaculture water By Alice Mahr
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armed salmon is by far the most imSortant ÂżnÂżsh sSeFies JroZn by &anadian aTXaFXltXre SrodXFers Srimarily off the Foasts of %ritish &olXmbia 1eZ %rXnsZiFN and 1oYa 6Fotia ,t aFFoXnted for of the total YolXme of the aTXaFXltXre indXstry and of its YalXe in Today &anada SrodXFes of Jlobal farmed salmon ranNinJ foXrth behind 1orZay the 8 . and &hile 'RLQJ PRUH ÂżVK ZLWK OHVV ZDWHU
The aTXaFXltXre indXstry faFes the FhallenJe of SroYidinJ an amSle sXSSly of MXYenile ¿sh smolts throXJh larJer hatFheries Zithin limited sSaFe 2ne issXe is the aYailability of freshZater resoXrFes 2n a Sro-rata basis eaFh ¿sh reTXires the same amoXnt of Zater to deYeloS Zhether in a larJe or small system The e[SandinJ aTXaFXltXre indXstry has to Xse limited sSaFe and freshZater in a sXstainable Zay This entails redXFinJ enerJy FonsXmStion reFoYerinJ enerJy and nXtrients and enhanFed Fontrol of the rearinJ enYironment animal health and Zelfare and bio seFXrity Traditionally, salmon and trout breedinJ Slants used a ÀoZ-throuJh system Zhere Zater is used only onFe The Zater is abstraFted, treated to a very limited extent, and has a system retention time of approximately one hour (nerJy Fosts, related to pumpinJ, disinfeFtion and efÀuent treatment, prevent the industry from produFinJ Fost-effeFtive and sustainable sea food $s abstraFted Zater Tuality Fan vary dramatiFally, proFess stability Fan be dif¿Fult to sustain To help meet this FhallenJe, .r Jer.aldnes, a division of 9eolia :ater 6olutions TeFhnoloJies, developed .aldnesŽ 5$6, a reFirFulatinJ aTuaFulture system, to reFyFle Zater in landbased aTuaFulture farms ,ts FonFept and proFess desiJn is based on a tiJht and perfeFt inteJration of all parts of the Zater treatment system The result is FompaFt plants www.esemag.com
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The RAS process has been successfully used in Norway and in Asia.
Zith very small footprints, drastiFally reduFed use of pipinJ, and optimi]ation of pumpinJ head and enerJy Fonsumption &ompared to traditional ÀoZ-throuJh hatFheries, a reFirFulatinJ aTuaFulture system reduFes Zater Fonsumption by up to ,n the 5$6 proFess, a movinJ biomass is in Fontinual FirFulation, prohibitinJ the enriFhment of unZanted material The 5$6 solution enables the reuse of proFess Zater in ¿sh-breedinJ faFilities and Jives an extended retention time, alloZinJ temperatures to be maintained Zith minimal enerJy :ith reJard to external threats suFh as sea liFe, it is far more bene¿Fial for the fry baby ¿sh to spend less time in the sea-FaJes and more time in the 5$6 onshore faFilities :ater Tuality is stabilised and Fonsistent, alloZinJ hiJh Tuality fry to thrive before beinJ transferred to maritime ¿sh farms The .aldnes 5$6 solution is desiJned to inFrease produFtivity and prof-
itability Zhile loZerinJ aTuaFultureÂśs environmental impaFt ,t reduFes Zater Fonsumption in the industry, Zhile removinJ orJaniF matter, ammonium, nitroJen, suspended solids, &2 and harmful baFteria viruses 6imultaneously, p+ and alNalinity are optimised, alloZinJ a Zide variety of speFies to thrive, inFludinJ Fold Zater, tropiFal, fresh and salt Zater Âżsh 3roduFtivity inFreases of up to have been doFumented Zith the 5$6 system, mainly due to siJniÂżFant deFreases in Âżsh mortality, improved Âżsh environment and Zater Tuality The 5$6 proFess has been suFFessfully implemented by several smolt produFers in 1orZay, and in $sia 6everal proMeFts are also under Zay in (urope and other parts of the Jlobe Alice Mahr is with Veolia Water Solutions & Technologies Canada. For more information, E-mail: John.Cigana@veoliawater.com January/February 2014 | 67
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