Hydrodynamic form

You might get some insights into ship-wave creation from Michlet.
But, as Tom Speer suggested, ambient waves are likely to be more important.

 

In order to use the collector as both water inlet and outlet, and to assure a smooth flow behind it, I think it will require an external form with a cross-sectional shape similar to that of jet engines. A possible configuration could look something like this one:



The hull openings for water inlet should be covered with inclined vanes (as described by TSpeer which should act as gross filter grille against the bigger debris. The span (or transversal length) of the collector/scoop/wing should not be too big, or else the areas near the tips will not feel the suction from the pump at the root, and the water will tend to go around the collector rather than through it.
The inflow area of the diffuser and the outflow area of the nozzle should be carefully matched to the openings on the hull and to the volumetric flow of the pump, in order to ensure that all the water coming towerds the collector gets processed. Considering that there will be a variability of vessel's speed, a variable-rpm pump will be required.

A separate propulsor will be necessary for moving the ship, as the head of the filtering pump shall be calculated for the pressure losses in the filtering system only, for reasons of efficiency. Imo, you shouldn't count on the jet outflow from the rear of the wing as a mean of propulsion, because it would be very energy-inefficient. the jet outflow serves only to maximize the volume of water collected by the scoop and processed by the filtering system.

That's my two cents worth...

Cheers

 

You might want to look at the "Boyan Slat" project pages, and the TEDx talk for more ideas. The concept is very similar to your idea, but for cleaning up plastic in the ocean.
http://www.boyanslat.com/

 

That's another interesting way of doing things. Boyan Slat's concept employs a practical observation that plastics and other debris tend to collect in the coves, brought there by currents and waves. The span of those collectors looks way too big for them to be effective. And I foresee half of them being torn in pieces within few years by the propellers of passing vessels. But we shall see. For sure that young boy knows his stuff when it comes to marketing and hype.

 

I'd take a look at modern dust collector systems such as reverse jet baghouse systems and cartridge systems. The stuff you are collecting is quite noxious. Liver carcinogens and toxic nonprotien aminoacids. A standard cartridge that can be collected, sealed, and taken in for processing would seem to be a decent idea. You need to seriously consider how all the steps in handling the concentrate will be carried out. You also might want to figure out how to detoxify the stuff you collect.

Leo's idea of down-elevator for 24 hours wouldn't be a bad system for cartridge purging.

You need some kind of cartridge collector coke machine system. Then keep the stuff in the dark and pump it down a pipe. You could also kill the ones you are interested in with brine. Darkness is probably cheaper than brine, but a brine cake would sink.

 

Hi again,

Thanks for every feedback! And great sketch about the wing construction.
I think i´m getting closer to the right shape but i could spend weeks on refining the shape and hull design and the whole project is just 10 weeks so ii think i´ll just make it as good as possible since it is a future vision. I´ve tried different softwares including michlet, paraview, openfoam and realflow but i cant understand anything about it. It would be nice to test different hulls in a software but it to complicated for me =)

But thank you all for all the great feedback and tips you've given me! I really appriciate this!

Kind regards!
Fredrik

 

I doubt that a small version of the vertical pipe idea will be very
efficient, but it might be worth a try. My colleague (Brian Kirke)
used a large diameter flexible tube rather than a solid wall pipe
which might be difficult to implement underneath a moving platform.

 

I was thinking of concentrating the algae with the OP's free swimming collector that could work the densest patches. Filter with permanent onboard filters and "package" into disposable paper cartridges. Then add some brine and jettison. The stuff will sink, and the paper cartridges would dissolve in a couple weeks. The idea is to keep people and denizens of the upper water column away from the stuff after it is concentrated. (so I'm now thinking more like a hay baler than a coke machine)

I couldn't find a number regarding the actual density of the stuff in a bloom, but taking 1/100,000 as a guess, and if you could pack 500 times algae to paper in a cartridge and still jettison it intact, that gets you 50 million water to paper wt ratio. That would be about 100kg of paper per sq kilometer of sea at a load of 1/100,000 down to a depth of 5 meters. The biggest potential problem I can think of is the amount of gassing from stuff that dies in the first 24 hours. It needs to stay sunk, but between the brine and the dark and getting jettisoned in the deep, it wouldn't be easy for it to survive. Just avoid floating particulates.

I guess the real issue is whether or not sequestering the stuff to the deep actually does any good long term. It is a short season, so I figure it might. Just let time do it's thing in the off season.

 

Hi again! Its an interesting idea you came with but i want tocollect the algae from the baltiv sea and use it to make fuel and plastics among other things. Then i´ll need to transport the algae from the vessel to the plant for processing. I´ve also tried to find numbers on how much algea there are for say 1 gallon of water. I´ve talked to marinebiologist about it but they say it's very diversed. I need this to know how big the dewatered algae tank should be.

Heres a video on the technology i think i´ll use to collect them. I will do a different design with this technology to able a larger amount of water per minute and make it fit inside the body.
Look from 0:40 to the end of the video.
https://www.youtube.com/watch?v=l7Ad-qOa8wc&index=39&list=FL8GjV8HBiH6tEAPpN5Xmsaw

Again i appriciate your help and i´m all ears about everything since i´ve havent "hammered" any proposals yet.

Kind regards
/ Fredrik

 

basic system flow for pickled algae.

Primary sieve -

60 sq meter induced at 1 m/sec. Concentration factor at least 1000 at better than 90% capture. Outflow is .06 cu meter/sec at a concentration of 1% algae.

Separator -

screen and jettison chunks, blobs and bycatch. About 5% algae loss expected.

Secondary dewatering -

Use UV and pumps to dewater and kill bacteria. Process to a mush. Inject UV treated brine and package. Jettison parcel.

Brine production -

Up to 20 MT per day to sequester 50 MT of algae (wild guess). Lets call it 60 kW continuous, but you get 20 MT of potable desalinated water for your effort as a byproduct.

That should get at least 1 sq kilometer of bloom cleaned up each day.

 

Fredrik, I crossposted with you above. The cyano algae is considered a carcinogenic substance. You would need to process it like nuclear waste until it is "cracked" in a digester. You are talking about tons/day of highly toxic compounds.

 

Thank you for your info and calculations. I dont know if the cyanobacteria species in the Baltic sea has the same type of toxin. The dominated one in the baltic sea in called "Nodularia Spumigena" but still...the machine has a sealed container inside the machine and when its emptied by a service boat it´ll still be sealed due to a direct hose-contact to the machine. And also after separating the algae the water runs through a secound filter before getting back to the ocean.

But i can't dig to deep in every aspect since it's only a 10 week project and a future vision. So the purpose of the projects is to show an example of how we could possibly do in the future. But i appriciate that you´ve breif me about your knowledge and it´ll be helpful for this project.