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View Full Version : Duckweed - the new super plant (like we didnt know already!)



MarkEinOz
6th June 2009, 09:54 AM
http://www.eurekalert.org/pub_releases/2009-04/ncsu-tsc040709.php


Researchers at North Carolina State University have found that a tiny aquatic plant can be used to clean up animal waste at industrial hog farms and potentially be part of the answer for the global energy crisis. Their research shows that growing duckweed on hog wastewater can produce five to six times more starch per acre than corn, according to researcher Dr. Jay Cheng. This means that ethanol production using duckweed could be "faster and cheaper than from corn," says fellow researcher Dr. Anne-Marie Stomp.
"We can kill two birds – biofuel production and wastewater treatment – with one stone – duckweed," Cheng says. Starch from duckweed can be readily converted into ethanol using the same facilities currently used for corn, Cheng adds.
Corn is currently the primary crop used for ethanol production in the United States. However, its use has come under fire in recent years because of concerns about the amount of energy used to grow corn and commodity price disruptions resulting from competition for corn between ethanol manufacturers and the food and feed industries. Duckweed presents an attractive, non-food alternative that has the potential to produce significantly more ethanol feedstock per acre than corn; exploit existing corn-based ethanol production processes for faster scale-up; and turn pollutants into a fuel production system. The duckweed system consists of shallow ponds that can be built on land unsuitable for conventional crops, and is so efficient it generates water clean enough for re-use. The technology can utilize any nutrient-rich wastewater, from livestock production to municipal wastewater.


Large-scale hog farms manage their animal waste by storing it in large "lagoons" for biological treatment. Duckweed utilizes the nutrients in the wastewater for growth, thus capturing these nutrients and preventing their release into the environment. In other words, Cheng says, "Duckweed could be an environmentally friendly, economically viable feedstock for ethanol."
"There's a bias in agriculture that all the crops that could be discovered have been discovered," Stomp says, "but duckweed could be the first of the new, 21st century crops. In the spirit of George Washington Carver, who turned peanuts into a major crop, Jay and I are on a mission to turn duckweed into a new industrial crop, providing an innovative approach to alternative fuel production."
Cheng, a professor of biological and agricultural engineering, co-authored the research with Stomp, associate professor of forestry, and post-doctoral research associate, Mike Yablonski. The research, which is funded by the North Carolina Biofuels Center, was presented March 21 at the annual conference of the Institute of Biological Engineering in Santa Carla, Calif.
Cheng and Stomp are currently establishing a pilot-scale project to further investigate the best way to establish a large-scale system for growing duckweed on animal wastewater, and then harvesting and drying the duckweed.


http://www.eurekalert.org/multimedia/pub/web/13348_web.jpg


http://www.eurekalert.org/multimedia/pub/web/13349_web.jpg

Ravnis
6th June 2009, 03:26 PM
I first came across aquaponics while doing research into alternative fuels and found "Bioponics". One of the reports I had found was extracting the oils from duckweed to make biodiesel. The left over can be used to feed livestock. Looks like a full system could be made here with a better way to clean water ways as well.

arthoz
8th June 2009, 05:42 AM
That is great news because my duckweed are growing like crazy just from fish water. From a two square foot tub, I could feed handfuls of duckweed to my tilapia everyday. It reduced my cost for fishfood by 50%.

Maybe this might be a bit out of topic but I was wondering...can tilapia survive healthily only by eating duckweed alone? I wanted to try breed black soldier flies but I need the organic matter for my garbage enzymes so I'm left with just duckweed...is it ok to feed my fishes with duckweed all the time? I noticed that their manure are greenish...

jpcw
11th June 2009, 07:28 PM
That is great news because my duckweed are growing like crazy just from fish water. From a two square foot tub, I could feed handfuls of duckweed to my tilapia everyday. It reduced my cost for fishfood by 50%.

Maybe this might be a bit out of topic but I was wondering...can tilapia survive healthily only by eating duckweed alone? I wanted to try breed black soldier flies but I need the organic matter for my garbage enzymes so I'm left with just duckweed...is it ok to feed my fishes with duckweed all the time? I noticed that their manure are greenish...
You could feed the duckweed to the soldier flies.

Tsaphah
12th June 2009, 10:20 AM
Anyone got plans on how to build a unit for making biodiesel from duckweed?
Fuel has just gone up again and if we could produce own food and fuel.....wonder how our reliever of revenue would feel about it:D

GaryD
12th June 2009, 11:34 AM
Hi,


You could feed the duckweed to the soldier flies.
We've been doing this for some time now......and it certainly works. I suggest that you let the duckweed drain for a day or two to reduce the water content before feeding it to the larvae.

Gary

jpcw
12th June 2009, 02:54 PM
Anyone know what the chemical process is to great ethanol from duckweed, or biodiesel for that matter. I think you need to convert the starch’s to sugar first before you can ferment the duckweed but how is that done?

PS This is purely from an academic point of view, it would of cause be illegal to actually distil any of it.

bunya boy
12th June 2009, 04:42 PM
Hi,

Anyone know what the chemical process is to great ethanol from duckweed, or biodiesel for that matter. I think you need to convert the starch’s to sugar first before you can ferment the duckweed but how is that done?


Having a small still for "essential" oils and water distillation is quite legal in Australia. Ethanol production is 'tolerated' in small quantities before requiring a license.
That being said, if you wish to convert Duckweed into Biofuel (read Ethanol) then the same process as is used for converting corn starch into ethanol should be employed. You would be better drying the Duckweed before grinding and boiling. It would be easier to handle.

This web site will tell you all you need to know.

http://running_on_alcohol.tripod.com/id20.html

Enjoy
Cheers IanK :D

jpcw
19th June 2009, 12:13 AM
Yep knew about the small still and "essential oils". A smal still would take forever to make enough to power a car though. No comment about enough to drink ;)

Actually I did a bit of research and there is actually an experimenters distiller license that allows you to produce unlimited de-natured ethanol for use in research for alternative fuels. From what I can gather it's just a nominal fee. You apparently have to de-nature the ethanol by adding around 5% of petrol to it and they can (probably will) inspect the premises.

Tsaphah
19th June 2009, 12:24 AM
Now we are getting closer to self sufficiency, own veggies, fish, quails/ chooks, beer, spirits, and fuel!!!
Just need to find a good source of power!

Restarted on my wind turbine last week, but now the missis wants the garage cleaned. Guess if I do it I'll have more room to work anyway:p

jpcw
19th June 2009, 01:37 AM
Restarted on my wind turbine last week, but now the missis wants the garage cleaned. Guess if I do it I'll have more room to work anyway:p

Have you seen the new power rebate system? They have dropped the solar rebate and are paying 5 times the number of REC's for a power system up to 1.5kw/h instead, equates to up to $7500 based on the current REC price. The good thing is that it applies to wind as well not just solar. Unfortunately for me the local council is not going to like me putting up a wind generator in my back yard.

Ravnis
19th June 2009, 07:02 PM
the research on the diesel was extracting the oil in an augerlike device. This oil would then need to be dried. I read of one person ading regular gasoline to the oil and using this as diesel. Haven't tried it yet. We made gasoline in my chemistry lab when I took high school chemistry, but haven't played with this type of chemistry in 25+ years.

kingjam
16th September 2011, 07:27 AM
How can I store the duck weed for fish food to be used at a later date? A friend took me to a place where we were able to get 3 buckets full and could have gotten more. I now have more than I can use for fish food. Would it be good as fish food if I dried it?
Kingjam

GaryD
16th September 2011, 09:17 AM
Hi KingJam,

You can dry it.....but we freeze it when we have it.

We use shallow trays to freeze the duckweed. Once frozen, we break it into shards and store them in a bag in the freezer.

Freezing it retains vitamin content better (than drying) and, by feeding it out frozen, the amount of mess it makes in the fish tank is minimised.

Once your fish are trained to eat it, they'll chase the frozen chunk around the tank.....eating it as it defrosts.

Gary