Forum Replies Created
March 7, 2010 at 4:43 am #9748
Wow, great find Altaica,
So the questions I have are:
- How much air are we talking?
- How much energy would it take to generate that amount of air?
- How big a wave can it break?
- Can it break a rogue wave?
I know you probably can’t answer any of these, but this is the first I have heard of any t ype of technology that could act as a breakwater on the open sea.
– You may get what you want, but will you want what you get?March 5, 2010 at 3:26 am #9726Pastor_Jason wrote:
On the one hand we have the thought that aero&hydro require close monitoring of the chemical/nutrient balance in the water and on the other a suggestion that aeroponics can be combined with composting and aquaculture. I’m a huge fan of aquaculture and composting but I don’t see what producing your own soil with composting will aid an aeroponic system.
Perhaps an explaination of how these systems would interact?
Sure, sorry I wasn’t more clear. When you do aquaponics, you are basically taking the waste stream from the fish and using it to feed nutrients to the plants. The plants then take up the nutrients, cleaning/filtering the water for the fish. Although you nomally think of growing plants in your compost, you can instead place the compost into drums and run water through them, also creating a nutrient rich water, much like aquaponics. Instead of growing the plants directly in the nutrient water, you suspend the plants and spray these nutrients directly on the root. The plants can then absorb the nutrients directly while maintaining aeration, which the roots need. The advantage of aeroponics is that you can grow the plants at a much higher density, conserving valuable space. One of the advantages of using compost is that it tends to naturally stabilize the PH of the system.
– You may get what you want, but will you want what you get?March 4, 2010 at 11:46 pm #9718xnsdvd wrote:
I feel the need to point out though, that quicklime sounds like a much MUCH cheaper and lower-tech alternative to seacrete. We get about 1 metric ton of barnacles growing on our 1500m
farm every month, it’d be a simple thing to burn it all in dried algae and then use it for construction material.
Yes, but I think you are looking at this wrong. Everyone has been thinking of Seacrete as the main product. If you look at what I am saying closely, you will see that what we are really doing is producing H2 with a byproduct of Seacrete. Going to a factory production model for this material opens entirely new possibilities. Further, while ferro-cement and quicklime are likely cheaper in the beginning, I’m not so sure now that this would still be true once mass production begins on the high seas. And if the power source is solar, we will need to find a way to level our power needs for nighttime. Hydrogen generation offers this possibility. Hydrogen is also useful for many other chemical processes.
Look, all I’m saying is, let’s explore the idea further and see where it takes us.
– You may get what you want, but will you want what you get?March 4, 2010 at 11:38 pm #9716Carl wrote:
As far as I understand, this relies on entirely new physics. Something about hydrogen atoms going to a lower energy state (that nobody has ever proven).
I’d say that is way more “out there” than fusion, which nobody denies is possible within established physics.
I did say it was a long shot, but the point is there are so many people working on alternative energy sources, I feel good that one or more of them will pan out in my lifetime. Yes, I’m aware of the fusion projects you mention as well. I think they have promise.
– You may get what you want, but will you want what you get?March 4, 2010 at 11:29 pm #9715Shouri wrote:
Soilless farming is alot more safer and easier as long as you are doing it professionally, and i don’t understand what you mean with shallow roots, you can adjust the roots size in a proper hydroponic system, plants grow their roots if they can’t reach nutrient solution. If one plant gets sick every plant in the same unit gets sick too in hydro unless you move the sick plant in time but why does your plant get sick in the first place? There shouldn’t be any organic substance near your facility, even adjacent soil with organic substances mixed-in is a potential threat to hydroponics, best enviroment for hydroponic facilities are inorganic floored greenhouses(asphalt,cement,desert,seastead;)…).
Obviously I disagree with most of what you are saying. Have you tried it? Look at the website http://www.aeroponics.com/ given by i_is_j_smith (great tlink by the way, thank you) and click on the link Aero vs. Hydro. Here is the picture shown:
Hydroponics doesn’t give proper aeration to the root. I have experienced this personally. That is why aeroponics is superior. I still think you will have major problems balancing the hydroponic chemicals at sea. Further, these chemicals are not freely available on the high seas, so you will not be self-sufficient. You seem to be scared of organics, as though anything organic is a source of disease. That is nonsense. Nature has a balance, good organisms and bad. Unless you are in outer space, there will always be some contamination at some point, even at sea. Strong plants have natural immunity from disease. Good organisms help keep the system in balance. All that is needed is to create an environment that favors the good over the bad, the plants do the rest.
And I see no reason that aeroponics cannot be combined with aquaculture and composting. This will provide extremely high yields with a minimum of outside inputs; all of the materials will be readily available.
– You may get what you want, but will you want what you get?March 2, 2010 at 5:29 pm #9697
Fusion still sounds far off to me. I’ve been following the work of blacklightpower.com. It’s a long shot, but I think alternative energy in one form or another is coming. Energy is the key to Seasteading.
– You may get what you want, but will you want what you get?March 2, 2010 at 2:08 pm #9693admiral wrote:
Another option to increase accretion rates is to use the concentrated brine left by boiling seawater for energy either with solar concentrators or a vacuum boiler OTEC system.
Yes, you did remind me, I forgot in my last message to mention that the solution in the closed loop should be at a slight vacuum to encourage CO3 beling released from solution at the cathode. I have thought about concentrating the ocean water, but I think it would be impractical because of the amount of energy needed to concentrate the brine; obviously OTEC would change that entire equation. Instead I’m focusing on concentrating just the needed ions in the solution by thin membrane and electrolysis.
– You may get what you want, but will you want what you get?March 2, 2010 at 2:07 pm #9692admiral wrote:
I could see producing calcium carbonate flakes or powder using a rotating drum as an electrode and collecting it by scraping it off. Maybe the hydrogen gas from the reaction could be collected as well to reuse as fuel, which would lower the net energy going into the process. Interesting patenet on the cellulose fiber/crytalline graphite material. The 100% argon atmosphere is a pain but it would be an interesting material, cellosic fiber with a diamonoid coating.
Yes, this is another possible embodiment. My only concern is breaking off the Calcium carbonate – if you have ever tried removing scaling…. That’s why I’m looking for a more disposable cathode material – cathodes that can be broken up and mixed with the limestone aggregate. I’m thinking more now about using pure graphite as the cathode material. The carbon in the graphite should enhance the overall reaction:
2Ca++ + 2C + 3O2 -> 2CaCO3
The carbon coming from the graphite, the Oxygen from the disassociation of H2O at the cathode. In other words, the graphite will get oxidized and added to the total available Carbonate in the local solution, further precipitating the Ca++ out as CaCO3. I’m hoping that there is someone here that knows chemistry better than me to check this. Also, if this graphite sheet/drum could be heated, it would further increase the amount of CO3 available at the local surface near the cathode, removing the need to heat the entire solution; with the heat coming from solar collectors. Applying ultrasound at the cathode would also make the CO3 more available near the surface by means of agitation. Using an inverted sheet/cathode would also likely increase the available CO3, as it tends to disperse upwards, having a lower specific gravity. All of these embodiments should cause the reaction to more favor the formation of Limestone over Magnesium hydroxide. You could also place the cathode much closer to the anode and slowly pull it farther away as the precipitate forms on the cathode, thus reducing the total resistance and energy usage. Adding small amounts of Sodium carbonate to the solution may also increase the accretion rates and favor the CaCO3 reaction.
Also, if there is a way to remove or sequester the Mg+ from the solution and/or increase the Ca++ concentration, that should also improve the reaction and quality of the product. We know for example that the Mg+ can be removed by high current electrolysis; and as you have pointed out, the magnesium itself does have potential applications.
There is also a use here for thin membrane technology. In this embodiment, the solution used would be kept in a closed loop and flowed past a thin membrane with fresh ocean water on the other side. As Ca++ and CO3 are depleted from the solution, they would be replentished by new Ca++ and CO3 ions moving across the thin membrane from the ocean water. This has many advantages. For one, the solution could potentially be kept at a higher temperature than the ocean water. The available Mg+ ions in the solution may also be more easily controlled and/or removed. For example, by placing multiple membranes between an anode and a cathode, you should be able to concentrate the Mg+ in one solution layer, and the Ca++ in another layer, due to the Mg+ being more mobile at higher currents. Another advantage is that the Sodium carbonate would not be as easily lost to the environment, as it would be recycled until it is used up in reactions.
The goal here is to increase the available Ca++ while reducing the Mg+ and increase the availability and concentration of CO3 at the cathode. All of this will cause rapid formation of the desired CaCO3 product. I think all of these embodiments can be tested on dry land in a suitable laboratory environment prior to final testing at sea.
And yes, much of the energy used in the electrolysis will be generating H2, which can now be saved and used. So now we have a usable energy by-product – I’m sure we’ll find some use for . As I’m writing this, I’m thinking that the CaCO3 precipitate is better if it does not aggregate on the cathode – we can filter it out on drums and use the Limestone powder in large molds. It would also solve the electrical resistance problem. After all, this is a far better building material.
– You may get what you want, but will you want what you get?March 2, 2010 at 1:14 pm #9694
Cool. Any chance you have access to a boat for testing at sea?March 1, 2010 at 2:01 am #9676xnsdvd wrote:
Just thought I’d post that we(Hadean) might be building a shop sometime in october with 4, 20ft containers laid side by side with the middle walls cut out to create a large room. Mind you, this will be on shore. Though we might be placing one on the farm once our stress-testing is completed.
Here’s a useful link: http://www.nordana.com/Equipment/ByName/40_High_Cube.aspx
High cube containers offer an extra foot of headroom, which, IMO is perfect for most people. And yes, prices in Singapore are approximately US$800 to US$1200.
I had no idea high cube containers even existed. Yes, this changes everything. I could really see these being made into primary structures. Fantastic stuff!
Who is Hadean?
– You may get what you want, but will you want what you get?March 1, 2010 at 1:57 am #9675admiral wrote:
Seacrete is viable as a coating on a sandwich panel structure made of a conductive metal like aluminum or magnesium. Magnesium is readily available from seawater and also showed the best growth results with the least power consumption in Eric Lee’s experiments at Stanford. Unfortunately, Lee’s results are no longer online but a partial archived version is at http://web.archive.org/web/20070824145637/http://www.stanford.edu/~erlee/seament/seament.htm . Some magnesium is consumed in the process since it acts like a battery.
Great stuff Admiral! I had reviewed the link you gave me years ago, but I’m very glad I re-read it. Yes, I really liked your ideas for both the panels and for using the Magnesium. In reviewing article and chemical reactions, a few things stood out. First, the accretion of Calcium Carbonate is but a byproduct of releasing of H2 and the resulting localized change in PH. From the paper:Seament wrote:
The seament electrodeposition reaction is initiated by placing two electrodes in sea water and applying a voltage across the electrodes sufficient for hydrogen gas to be evolved at the cathode. For now we will ignore what is happening at the anode and concentrate on the reactions that are occurring at the cathode where the seament is being deposited.
(1) As the voltage across the electrode rises there will be a point where the cathode will become electronegative enough to attract the hydrogen ions in solution in water, donate electrons to them and take them out of solution by converting them into hydrogen gas which then bubbles up to the surface of the ocean.
2e- + 2H+ < => H2 (gas)
(2) As the hydrogen ions become depleted near the electrode, there is a chemical reaction involving the carbonic acid in sea water that will try to reestablish the old equilibrium concentration. Carbonic acid can disassociate to form bicarbonate ions and hydrogen ions by the reactions:
H2CO3 < => H+ + HCO3- < => 2H+ + CO3–
What is striking to me is that this equalibrium only triggers accretion because of the increased concentration of Carbonic acid in the vacinity of the electrode. This opens the possibility that there may be other chemical additives that could be used to increase this concentration. For example, could we add Sodium Carbonate to facilitate CaCO3 formation? I’m no chemist, so maybe I have this wrong. Further the article mentions agitating the water to release the CO3– from solution, just like shaking a soda bottle. Maybe use ultrasonic transducers? Whether my chemistry is right or not, the larger question is, can we modify the reaction to favor CaCO3 precipitation?Seament wrote:
As the hydrogen ions near the cathode become depleted this reaction because of LeChatelier’s Principle will move to the right to try to create more H+ species in solution. This will also increase the concentration of carbonate ions ( CO3– ) in solution. In fact the concentration of CO3– ions can become large enough such that the reaction:
Ca++ + CO3– < => CaCO3 (solid)
can proceed to the right, precipitating out solid calcium carbonate onto the cathode when the solubility product of Ca++ and CO3– exceeds that of what can be kept dissolved as ions in solution. This solid calcium carbonate, also called argonite, is the good stuff in seament: hard, strong and nearly insoluble.
The precipitation from solution of CaCO3 is the first accretion related reaction that occurs as the cathode voltage and current density is ramped up. As the cathode voltage and current density is increased further another reaction starts to dominate.
Ok, here is my bigger idea. Instead of trying to make the entire structure from direct accretion, just focus on accretion of the CaCO3 onto metal sheets. The sheets of CaCO3 can then be mechanically broken up to produce aggregate of various sizes. The aggregate can then be mixed with lime and water and poured into forms as usual. In other words, can we use this process just for the creation of aggregate? Would this be more efficient since the electrical resistance would be easier to control in thinner sheet formation? Can we use chemical additives in combination with ultrasound to fascillitate Calcium Carbonate formation? Could we also use chemical additives to sequester the Magnesium and prevent Magnesium Hydroxide formation? Can we use solar heat and/or vacuum pressure to assist in releasing the CO3? It seems to me that the possibilities have not yet begun to be explored.
Here is another patent I found of interest:
It carbonizes cellulose to create a thin graphite”shell”. This cellulose can be formed into sheets for use as a cathode in place of the metal sheeting. The cellulose would ultimately mineralize, adding more strength.
All of this is speculative at this point. But my argument is that we should not be dumping the concept of Calcium Carbonate as a building material just yet.
– You may get what you want, but will you want what you get?February 28, 2010 at 11:09 am #9669J.L. Frusha wrote:
Plants take-up the nutrients, either way. The easiest way I know of is to vermi-culture in the grow-beds and use Black Soldier Fly larva to convert human waste to maggots, to feed the fish. The trick is what other processes you use getting there. The converted compostcan also be applied to the grow-beds for the vermiculture.
I’d like to see how a methane digester, followed by aerobic digester. Next, solids would be separated and go through the composting/BSF treatment, then to the aquaponics, myself. Liquids go back into the methane digester, to mix the incoming waste into a usable sludge…
The more the system recycles, the better the efficiency. Todays food becomes food again… Just have to watch that it doesn’t get high salt concentrations, killing-off parts of the cycle.
Can it work? Yes, BUT it will be a PITA until the system gets developed and balanced, to work in better harmony. After we buy my parents house, I’ll start working toward that system.
I like your ideas, and I’m glad you are planning to actually try this. So in my mind it is only a matter of determining the most effective method(s). For example, what converts human waste the fastest, Red worms or Black Fly larva? Is there any difference in the protein content? Which requires the least labor effort? Which bio-cycles are the most resiliant?
Yes, salt buildup may be a problem. Only way to find out is to try it.
My only concerns with aquaculture are:
- How labor intensive is it for maintenence, routine tasks and system supervision?
- How resiliant is the process to operator mistakes and plant disease?
- I don’t think cost is an issue.
I would love to try some of these alternative methods myself, but sadly I have no place for this right now. When you do get to try this, please keep good records of your time usage, system inputs and production so it can be compared to other potential bio-mass recycling methods. I think it would make for a good Seasteading study.
– You may get what you want, but will you want what you get?February 28, 2010 at 10:49 am #9668CrosiarCM wrote:
I don’t think there is any significant density differences between the different types of plastics. They are usually sorted by hand using the markings on the underside of the cartons/containers. I don’t think getting low cost labor would be any issue, but I never see this discussed here. .
It seems that is can be done. http://www.plastic-separation.com/EN/centrifugesEN.htm#ReCENT
Wow, I have never heard of this; thanks for the great link. Ok, so this is even more possible than I had imagined. To some degree, I’m suprised there is no one out there now scooping up this concentrated waste for recycling. I think we only need to determine the economics of this.
– You may get what you want, but will you want what you get?February 25, 2010 at 8:32 pm #9658
I agree with all of your points. But I have seen no other structure that can act as a breakwater on the open sea – they all assume shallow coastal waters. The scale that it would have to be built is the issue, but could the idea still be applied in some way? I also wonder how much drag it would have due to resistance as the waves flow through. Somehow I feel like there is some answer here, but right now all I see are questions.
– You may get what you want, but will you want what you get?February 25, 2010 at 10:11 am #9653
Wow, I’m impressed at the size and speed to which my post got a reply!
Thanks for the warm welcome
You’re very welcome. I find it hard to get people to engage in deeper discussions in these forums – quick quips, but no thought out responses. New people tend to bring new ideas and fresh perspective, and for that I thank you.
Concerning the shipping containers, what about the possibility of welding them together to create larger rooms?
Also do they float? If they do then they could be used as a foundation on which the rest of the seastead is built.
Yes, they can easily be linked together to make larger rooms. Holes can be cut for doors and windows to be installed. Electricity and plumbing can also be installed.
Your comment about pelletising the plastic is a wonderful idea. As for seperating the types of plastic, could we use a centrifuge(wave powered) to make it less labor intensive?
I don’t think there is any significant density differences between the different types of plastics. They are usually sorted by hand using the markings on the underside of the cartons/containers. I don’t think getting low cost labor would be any issue, but I never see this discussed here. All I see is talk of rich people going out to sea in floating casinos/whore houses. I don’t see how you can make a sustainable society from this. Anyway, I digress. See http://www.lotfi.net/recycle/plastic.html.
I also agree with you on hemp, it is a wonderful plant that I forgot to add on my other post.. Bamboo requires a large root system to grow tall, so it may be limited in seastead use as well. To address the limited space issue we could begin culturing a population toward our goals, I mean if a MIT student can turn carrots purple for his thesis project, I’m sure we could something as well.
I like your idea of underwater robotics dredging the sea floor, and as for sea sand, perhaps we could use bamboo instead of iron rebar? Also we could melt it down to make glass.
Here is an existing discussion on bamboo reinforced concrete seasteading.org/interact/forums/engineering/structure-designs/bamboo-reinforced-concrete and a study romanconcrete.com/docs/bamboo1966/BambooReinforcedConcreteFeb1966.htm.
Some arguement is made against it’s use because of it’s lower tensile strength and greater “flexing”; however, in some applications this is considered a superior trait. For example, it would be an excellent subsitute for Non-bearing concrete walls. Sheetrock performs very poorly in marine environments. However, I suspect that bamboo will be difficult to grow at sea, for the reasons you give. Hemp cellulose makes great fill in concrete and a laminate hemp fiber layer can give it great strength. This makes an excellent light weight cement fiber board that can be used just like sheetrock. And unlike sheetrock, it will not mold or mildew if it gets wet. Oh ya, it is probably alright to use sea sand with this since the salts will not corrode hemp.
What can we grow/make that we can use to filter sea water? ( such as the plankton and silt )
Once filtered, we can then use solar collectors to create fresh water and sellable salts.
Not sure on the sea water filters, and I’m not sure what application it would have. But I would like to talk about making fresh water. Most methods of making fresh water are very energy intensive. The only other option I have seen is some form of open-cycle OTEC. Unfortunatley, OTEC has been discarded as an energy production mechanism because of it’s high startup costs and it is an unproven technology. But one of the main features of OTEC is that of bringing up deep sea water from a km or more. This water can be as low as 40 F. But the cost of pumping this cold water to the surface for OTEC is high, but that is only because of the large quantity of cold water OTEC requires. I think this cold water resource as been too quickly thrown over-board with OTEC itself. Forget OTEC for a minute, and just consider the value of this cold, nutrient rich, sea water. The first obvious use for this cold sea water is to condense fresh water from the warmer surface water. Would the energy required to pump this deep seawater to the surface be more or less than other fresh water purification schemes? I suspect it will be far cheaper to pump it to the surface for this use. Next obvious application is for airconditioning. This is another energy hog – and here is all this cold water just waiting for you under your Seastead. Then there is the use for refridgeration, another consumer of electricty. It can also be used to improve the efficiency of any heat pump, such as large walk-in freezers. And finally, if you are using any heat engine based power generation, the cold water can be used to improve efficiency in the condenser stage.
Now if the costs to pump this cold water to the surface proves too high, consider a closed loop to the ocean depth. You pump water to depth, heat exchange it to the colder deep water and cycle it back to the surface for use. Because it is closed loop, you do not incur the pumping energy cost from the differences in water density.
A long term option that would be really cool is if we figured out how to genetically engineer a plant to be the seastead. Of course I know that it would be nigh near impossible today, but in 20 years who knows
I thought about this idea when I was a kid – growing genetically engineered houses and structures – my parents just laughed at me. But someday…
In the mean time, I really like the idea of growing structures from seacrete – all that is needed is a scaffolding for it to grow on and energy. That’s why I’m always looking for ways to produce copious quantities of energy at sea – it is needed for everything we want to do.
Please check out my thread seasteading.org/interact/forums/engineering/infrastructure/coolearth-and-solar-balloons. I’m sad I have no replies .
– You may get what you want, but will you want what you get?
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