Breath­ing space

James Fla­herty ex­plains an oxy­gen sys­tem that low­ers mor­tal­ity risk

Fish Farmer - - Ras – Technology -

SEV­ERAL years ago, Ad­sorptech at­tended its first Aqua­cul­ture Amer­ica trade show in Las Ve­gas, curious about fish farmer needs re­gard­ing oxy­gen sup­ply. One night at a happy hour, sip­ping a cold beer, fate put a ma­jor RAS de­sign en­gi­neer and a farm insurance agent at the same stand up ta­ble. As a curious en­gi­neer, the ques­tion was asked: ‘What is im­por­tant to the fish farmer about oxy­gen sup­ply?’

In ad­di­tion to the ob­vi­ous cost re­ply, both low power con­sump­tion and re­li­able sup­ply sur­faced as crit­i­cal.

Con­fer­ence papers were pre­sented about the in­fancy stage of Low Head Oxy­gen (LHO) tech­nol­ogy ad­vances. Low­er­ing wa­ter pres­sure would sub­stan­tially im­prove the farm’s over­all power op­er­at­ing cost.

Many pre­sen­ta­tions dis­cussed how RAS might just be turn­ing the cor­ner from in­ter­est­ing to prof­itable if all equip­ment sup­pli­ers were to ‘row in the same di­rec­tion’ to im­prove RAS economics.

Af­ter the show, the Ad­sorptech team put our heads to­gether to see if we could come up with some­thing in­no­va­tive and cost ef­fec­tive in the oxy­gen ca­pac­ity range that present and fu­ture fish farm­ers would need.

From many long and of­ten­times bois­ter­ous brain­storm­ing ses­sions and more than a year of pro­to­type test­ing, the EcoGen Oxy­gen VPSA (vac­uum pres­sure swing ab­sorp­tion) was born.

Polling sev­eral farm tech­nol­o­gists, all tar­geted cir­cu­lat­ing wa­ter pres­sures be­low 3 barg (43 psig). Two stan­dard EcoGen mod­els were cre­ated, one each at 1 and 3 barg (15 and 43 psig) to sat­isfy all farm and LHO devel­op­ers’ targets.

At ei­ther pres­sure, EcoGen rep­re­sents the most power ef­fi­cient source of oxy­gen in the world. A 1 barg sys­tem re­quires 0.24 kw/kg oxy­gen which is 10 per cent less power (and 20 per cent to 25 per cent lower cap­i­tal), both ma­jor im­prove­ments for farm re­turn on in­vest­ment.

The farm de­signer noted that at 50 per cent of the oxy­gen availabili­ty, the fish would not grow; but they also would not die. One can­not make a profit with dead fish.

The EcoGen is the only oxy­gen pro­duc­tion tech­nol­ogy in the world to have built in 50 per cent re­dun­dancy.

When one of the front end com­po­nents is out of ser­vice for any rea­son, such as an­nual oil change, the EcoGen can still op­er­ate at 50 per cent of its pro­duc­tion ca­pac­ity, thereby low­er­ing mor­tal­ity risk

and avoid­ing higher back-up liq­uid oxy­gen cost.

The insurance agent men­tioned ear­lier claimed that the farm insurance pre­mium could be lower as a re­sult of lower mor­tal­ity risk.

An­other unique EcoGen fea­ture is its pack­ag­ing, with only two parts to in­stall com­pared to multi-com­po­nent sys­tems re­quir­ing additional in­stal­la­tion cost, time, and risks.

EcoGen pack­ag­ing elim­i­nates the need for a build­ing to house the oxy­gen equip­ment, and the sys­tem is cur­rently op­er­at­ing in en­vi­ron­ments rang­ing from nearly 120F to-40F.

As the av­er­age size of RAS farms in­crease, the im­por­tance of EcoGen rises pro­por­tion­ally. The model range is per­fectly suited for farm sizes of about 300 tonnes per year re­quir­ing 1,800 kg/day oxy­gen and more.

When pur­chas­ing your own oxy­gen gen­er­at­ing equip­ment, about 20 per cent to 30 per cent of your al­ready lower to­tal oxy­gen costs es­ca­late – power and main­te­nance. Also, multi-year LOX con­tract obli­ga­tions will im­pact the farm bal­ance sheet which is some­thing most peo­ple sim­ply do not re­alise.

James Fla­herty, pres­i­dent and CEO of Ad­sorptech, will be pre­sent­ing a pa­per on the tech­ni­cal and eco­nomic im­pacts of al­ter­na­tive oxy­gen sources at RAS tech. Ad­sorptech will be avail­able in booth 31 at the RAStech trade fair.

“Both low power con­sump­tion and re­li­able sup­ply are crit­i­cal to the fish farmer”

Above: EcoGen model

Be­low: An EcoGen en route to an Is­raeli farm in 2016

Newspapers in English

Newspapers from UK

© PressReader. All rights reserved.