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Tavascarow

Energy from seaweed

Seaweed problem could provide biofuel solution
Hairyloon

Did it really take them this long to think of that?
Tavascarow

I have always been a follower of science & am truly glad we don't still live in the world of necromancy & voodoo but if scientists have one fault it's making a simple solution more complicated to justify a bigger research budget. Wink
wellington womble

Wouldn't it be too soggy to burn?
Shane

The stuff that blows in in huge quantities all over Worthing beach every summer just in time to release its pong for the world bowling championships gets so dry and crispy that it cuts your feet to ribbons.

The stuff on the surface, at least. The three feet below the crust has the consistency (and smell) of rotting slurry, which is always pleasant when you find yourself up to your knees in it.
Tavascarow

Wouldn't it be too soggy to burn?
You don't have to burn it to extract energy, at least not initially.
Anaerobic digestion to extract methane would be my choice although the high salt content might affect the efficiency on the bacteria.
Hairyloon

Anaerobic digestion to extract methane would be my choice although the high salt content might affect the efficiency on the bacteria.

I'd be very surprised if there are no salt tolerant anaerobic bacteria.
Falstaff

Wouldn't it be too soggy to burn?

Don't you go trying to introduce LEVITY into such a serious subject ! Evil or Very Mad

Nick

Anaerobic digestion to extract methane would be my choice although the high salt content might affect the efficiency on the bacteria.
I'd be very surprised if there are no salt tolerant anaerobic bacteria.

Something sounds like it's eating the three feet of stuff Shane wades in on his way to his Crown Green jamboree.
Mistress Rose

Apart from upsetting the wildlife that has set up home in their seaweed farms, that looks like a good idea. As with other biomass waste, the fun comes in trying to extract the energy or turning it into oil. I wonder if we ought to be more concerned with using it in other ways to make power rather than being blinkered by turning everything into oil. Yes, we do need something like that to make chemicals, but we don't need to go through that stage for energy production. Ty Gwyn

As long as they leave the Laverbread variety alone,all is well,lol. Hairyloon

Apart from upsetting the wildlife that has set up home in their seaweed farms, that looks like a good idea.
I cannot see that is likely to be a problem, at least not for the populations: the individual critters that get hauled up with the harvest might get upset, but the overall increased availiability of food would more than make up for that.
Cathryn

Why is a seaweed farm so eco friendly? What would this bay look like if I started to grow a mono crop in it? It's hardly going to leave the ecology unchanged. What's an excessive amount of seaweed? An amount that gets in the way of our recreational use of it? Is the sea overproducing seaweed? Why? Because it smells funny when it rots or something more serious?

Hey, convince me, it would be perfect for me personally.
dpack

Anaerobic digestion to extract methane would be my choice although the high salt content might affect the efficiency on the bacteria.
I'd be very surprised if there are no salt tolerant anaerobic bacteria.

lots of em
Hairyloon

Why is a seaweed farm so eco friendly? What would this bay look like if I started to grow a mono crop in it?
Why grow a monocrop? If it is just for fuel, then biomass is biomass.
Quote:
What's an excessive amount of seaweed? An amount that gets in the way of our recreational use of it? Is the sea overproducing seaweed? Why? Because it smells funny when it rots or something more serious?

It is overproducing when there is so much that it self shades itself to death. Then it starts to rot, which uses up all the oxygen...
Cathryn

Not sure about the shading itself to death but brief reading that I've done suggests that one reason for overproducing is because of excessive nitrogen levels which are apparently run off from the land? Wonder how sea weed farms would encourage growth. (Does a cynical tone come through on the forum?)

The article was expounding this as an eco friendly bio mass crop and I cannot see how it could be.
Jamanda

Lanildut in Brittany is big on seaweed. It's kelp that they harvest. They have contraptions on the back of the boats that work like giant pasta forks. I think it needs a more sheltered bay than yours Cathryn. Cathryn

The beach is SSSI so it wouldn't happen in any case. Smile Hairyloon

Not sure about the shading itself to death...
It is algae, it is not like proper plants which send food down from the leaves.
Quote:
but brief reading that I've done suggests that one reason for overproducing is because of excessive nitrogen levels which are apparently run off from the land?

Yes, very often. But before you asked when it is overproduction, not why.
Tavascarow

Not sure about the shading itself to death but brief reading that I've done suggests that one reason for overproducing is because of excessive nitrogen levels which are apparently run off from the land? Wonder how sea weed farms would encourage growth. (Does a cynical tone come through on the forum?)

The article was expounding this as an eco friendly bio mass crop and I cannot see how it could be. You have answered your question already. It is growing excessively in some places because of nitrate run off so why not harvest it? Personally I wouldn't use it as a bio-fuel but as a fertilizer on the very land that has had the excess fertilizer. Mistress Rose

It has been used as a fertilizer for years. It has also been harvested for burning for glass making and other uses that need potassium chloride or nitrate. Ty Gwyn

It has been used as a fertilizer for years. It has also been harvested for burning for glass making and other uses that need potassium chloride or nitrate.

Calcified Seaweed is the one that comes to mind,

Did`nt know about the Glass making,interesting.
Hairyloon

Personally I wouldn't use it as a bio-fuel but as a fertilizer on the very land that has had the excess fertilizer.
Run it through an anaerobic digester and you can do both.
Tavascarow

Personally I wouldn't use it as a bio-fuel but as a fertilizer on the very land that has had the excess fertilizer.
Run it through an anaerobic digester and you can do both.
True.
& anaerobic digestion makes the fertilizer more stable. If used to replace some or all of the artificial nitrates & animal slurry there would be very little run off.
Plant a belt of short rotation coppice on the lower slopes to mop up any excess & I think (with the aid of the article) we have just designed a bioremediation system.
Of course the likes of Monsanto will say it would never work, & if there was any chance they would patent, & bury it. Wink
Tavascarow

It has been used as a fertilizer for years. It has also been harvested for burning for glass making and other uses that need potassium chloride or nitrate.

Calcified Seaweed is the one that comes to mind,

Did`nt know about the Glass making,interesting.
Calcified seaweed beds are a threatened habitat & not a sustainable source at current rates of exploitation.
There's a huge difference between harvesting kelp washed ashore & dredging the sea bed.
Also a huge difference in chemical composition. Calcified seaweed is more suited for raising the pH of acid soils than as a fertilizer substitute.
It's 50% CaCO3 10% Mg CO3 & if I remember correctly only about 1% NO3.
I know they have stopped dredging it in the Fal estuary years ago, because of over exploitation.
Cathryn

Not sure about the shading itself to death but brief reading that I've done suggests that one reason for overproducing is because of excessive nitrogen levels which are apparently run off from the land? Wonder how sea weed farms would encourage growth. (Does a cynical tone come through on the forum?)

The article was expounding this as an eco friendly bio mass crop and I cannot see how it could be. You have answered your question already. It is growing excessively in some places because of nitrate run off so why not harvest it? Personally I wouldn't use it as a bio-fuel but as a fertilizer on the very land that has had the excess fertilizer.

But that isn't what the article says. One project collects the excess that grows but the main plan (because that's not realistic in the longer term is it) seems to be large farms where they grow the seaweed themselves.
Ty Gwyn

It has been used as a fertilizer for years. It has also been harvested for burning for glass making and other uses that need potassium chloride or nitrate.

Calcified Seaweed is the one that comes to mind,

Did`nt know about the Glass making,interesting.
Calcified seaweed beds are a threatened habitat & not a sustainable source at current rates of exploitation.
There's a huge difference between harvesting kelp washed ashore & dredging the sea bed.
Also a huge difference in chemical composition. Calcified seaweed is more suited for raising the pH of acid soils than as a fertilizer substitute.
It's 50% CaCO3 10% Mg CO3 & if I remember correctly only about 1% NO3.
I know they have stopped dredging it in the Fal estuary years ago, because of over exploitation.

Swings and roundabouts Tav,
Usually raising the pH encourages clover,hence increases the nitrogen,so in-fact is a substitute to chemical fertilizer.

The 50% calcium is made up of the crushed sea shells.
I really don`t know how much seaweed it contains.
Tavascarow

It has been used as a fertilizer for years. It has also been harvested for burning for glass making and other uses that need potassium chloride or nitrate.

Calcified Seaweed is the one that comes to mind,

Did`nt know about the Glass making,interesting.
Calcified seaweed beds are a threatened habitat & not a sustainable source at current rates of exploitation.
There's a huge difference between harvesting kelp washed ashore & dredging the sea bed.
Also a huge difference in chemical composition. Calcified seaweed is more suited for raising the pH of acid soils than as a fertilizer substitute.
It's 50% CaCO3 10% Mg CO3 & if I remember correctly only about 1% NO3.
I know they have stopped dredging it in the Fal estuary years ago, because of over exploitation.

Swings and roundabouts Tav,
Usually raising the pH encourages clover,hence increases the nitrogen,so in-fact is a substitute to chemical fertilizer.

The 50% calcium is made up of the crushed sea shells.
I really don`t know how much seaweed it contains.
The clue is in the name my friend. Yes there is a small proportion of shell but the majority is the 'calcified' remains of a specific species of seaweed. It's more like crushed coral than a plant but that is what it is, & the habitat is quite rare, valuable & easily destroyed.
Quote:

3.2.2 MAERL
Divers have reported seeing maerl, calcified seaweed, on the seabe
d at the mouth of the estuary,
particularly in the vicinity of the wreck of the ‘Rock Island Br
idge’. Maerl beds are a sub feature of
the Fal & Helford SAC. The larger maerl beds, within the Rose
land VMCA in the adjacent Fal
estuary have been dated as approximately 7,000 years old and are we
ll known for their marine
wildlife as the interstices of the very slow growing maerl pr
ovide shelter and security for a wide
range of invertebrates and fish. Dead maerl which has accumulat
ed in substantial quantities in
various parts of Falmouth Bay not far from the Helford River also pr
ovides an interesting although
more mobile habitat.
from this document. Jamanda

It's also used for making agar, for growing bacteria, making jelly and various creams and potions in the cosmetics industry.
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