Covering Slurry lagoons??? Good thing or not???

[sjt01]

What is the formula for calculating how much acid is required ?

Depends on the buffering capacity of the slurry or digestate, best to use a pH meter. It should be about 4 kg/m3 for our digestate

 

[Blue.]

LECA (floating balls) will allow for free agitation. However in high rain fall areas keeping rain water out will be a high priority. When it comes to effective mixing under covers it come down to the design of the lagoon and type of mixing you put in. You can put mega mix systems under the sheet or a traditional PTO driven mixer that has cage built under the cover to accommodate.

On the point of tensioned cover over a lagoon it is possible but very very expensive.

Was going to cost the same as the lagoon for a caged stirrer back in 2005,having never needing to stir our old store I decided not to bother,rainfall was the main reason for the cover.

 

[multi power]

By lowering pH you move ammonia gas to ammonium ions which stay in solution rather than escape to atmosphere. The effect carries on from storage into the spreading, so you get much more N available to the crop. If you use sulphuric acid you are making ammonia sulphate fertiliser.
Health and safety - there is no way you would get me or any of the farm staff under a cover to degrit - the space would be near impossible to ventilate properly so would be a death trap. The cover would have to be removed on a regular basis for degritting, not an easy option so some might be tempted to go underneath.

I hadn't thought of the amoinia, I was assuming the cover was to keep rain water out
Quite right about the danger of the gas

 

[Chippy]

Would a covered lagoon containing separated digestate ever need stirring?

 

[Michael3112]

I did the same!

Ended up with a 5' crust,circulated it,blew air into it,bugs etc.. nothing worked! Admitted defeat and cut the cover off.

Ideally need a tensioned cover,not sure why they're only available for round stores.

When we took the cover off we were met by a crust we thought would be bad but bloody hell was twice as bad to the point mixers arent gonna cut an they have got a machine coming in to dig it off an desilt the bottom.

 

[Michael3112]

Have you thought about floating covers like LECA AeroTop?

https://www.aegltd.co.uk/aerotop-covers/

They were spoke about chief nephew has tried them in there new lagoon

 

[sjt01]

Would a covered lagoon containing separated digestate ever need stirring?

Not stirring but certainly degritting - a very solid layer of silt develops, not stirrable, needs jetting to shift. Photo shows Jex Plant doing a degrit a couple of years ago. Needed a biggish 360 to get all plant in place, a BIG air compressor and the yellow jetting device shown here. There was a good metre depth of grit after about 5 years.

 

[J Magee]

Would a covered lagoon containing separated digestate ever need stirring?

Yes it would. What sort of volumes are you talking about storing? With low dry matter Digestate you have more options for effective agitation with a cover on.

 

[J Magee]

They were spoke about chief nephew has tried them in there new lagoon

How are they getting on with LECA? IS it the LECA AeroTop? Not all LECA is the same.

 

[Chippy]

Yes it would. What sort of volumes are you talking about storing? With low dry matter Digestate you have more options for effective agitation with a cover on.

1 million gallon lagoon. Can’t decide whether I should put concrete tower in or lagoon. Was hoping if I separated my digestate I could avoid buying a huge stirrer

 

[maen]

If you separate and empty from centre. Ideally all sides of the lagoon should tapper to a low point in the centre. Fix a permanent suction pipe to the central of the lagoon and draw from a fixed sunken tank. This will almost eliminate the need to stir as the lagoon will mix as it is drawn to the centre rather like a plug hole in a sink.

 

[J Magee]

1 million gallon lagoon. Can’t decide whether I should put concrete tower in or lagoon. Was hoping if I separated my digestate I could avoid buying a huge stirrer

Hi Chippy, A lagoon will be cheaper than tower. Also for low dry matter slurry/digestate we can put in a jetting system which is a very cost effective way of mixing to keep any fine slit in suspension.

 

[Blue.]

Hi Chippy, A lagoon will be cheaper than tower. Also for low dry matter slurry/digestate we can put in a jetting system which is a very cost effective way of mixing to keep any fine slit in suspension.

Any info on the store in your avatar?

Looks like it’s mesh with a membrane?

 

[J Magee]

Any info on the store in your avatar?

Looks like it’s mesh with a membrane?

The the tank in my avatar is from your satellite slurry storage tank range. The tank is a solid silo tank, so not mesh. But tanks are lined with a PVC liner delivered in panels and depending on size take up to 4/5 days to construct. No concrete base needed. Tank and liner can be moved to another location if needed.

https://www.aegltd.co.uk/products/tanks/

 

[O'Reilly]

Is there a tie up between AEG and tanlake farm & machinery?

 

[J Magee]

Is there a tie up between AEG and tanlake farm & machinery?

So Tanlake went into liquidation. AEG bought some of the assets from the receiver and took on Dave Ellicott who is now are general Manager based in Devon. Apart from that AEG and Tanlake are two different companies. I hope this answers your question. If you would like to know more please let me know.

 

[davidroberts30]

Depends on the buffering capacity of the slurry or digestate, best to use a pH meter. It should be about 4 kg/m3 for our digestate

thinking outside my capacity here and standing to be well corrected
so a cube of acid would treat 250cube of slurry
would the cost of 2 cube of acid on 500cube of slurry release the required savings over fertiliser?

 

[sjt01]

thinking outside my capacity here and standing to be well corrected
so a cube of acid would treat 250cube of slurry
would the cost of 2 cube of acid on 500cube of slurry release the required savings over fertiliser?

A cubic metre of acid weighs 1.25 tonnes, so 25% more. If you are buying sulphur fertilisers, then sulphuric acid is the cheapest form (although much care needed!), so cost savings there before the extra N. In my calculations, the extra N has to pay for the capital value of the kit and operation. On our scale, buying in equipment is not viable, which is why I am building my own.

 

[davidroberts30]

A cubic metre of acid weighs 1.25 tonnes, so 25% more. If you are buying sulphur fertilisers, then sulphuric acid is the cheapest form (although much care needed!), so cost savings there before the extra N. In my calculations, the extra N has to pay for the capital value of the kit and operation. On our scale, buying in equipment is not viable, which is why I am building my own.

I take it I couldn't dump the acid in the lagoon while mixing it and pump it out?

 

[sjt01]

I take it I couldn't dump the acid in the lagoon while mixing it and pump it out?

The sooner you can get it mixed the more you will reduce losses - and it foams a lot! You can get some benefit by mixing in the tanker, but nowhere near the full amount.