Disolved urea

[Old apprentice]

Dissolving ordinary urea ,say 5 to 7 kg in 200 Lt sprayed with crop spraying nozzles per htr would this burn from now to June possibly 5 times. Information greatley appreciated thanks

 

[Barleymow]

Do it when crop damp , dissolve urea to spray headlands use normal nozzles on damp crop with no issues

 

[Oilseed]

I applied 10 Kg of urea in 200L with the T1 spray last spring as it was too dry for soil acting fertiliser to work. It just scorched on the overlaps.

 

[robs1]

Do it when crop damp , dissolve urea to spray headlands use normal nozzles on damp crop with no issues

Been thinking about doing this for headlands as we have small fields, how do you dissolve it ?

 

[Brisel]

Use fertiliser nozzles/stream bars to apply it. The guys melting their own will be better placed to comment here

@Clive @PSQ Apologies if I've missed out lots more.

 

[stroller]

Been thinking about doing this for headlands as we have small fields, how do you dissolve it ?

I used a 2500lt tank with a 2" camlock outlet connected to a petrol powered pump then back into the top of the tank. It only had a standard hatch in the top but it you're careful and hang the bag over the top and cut a small hole it will all go in, do it on some concrete and the little bit that gets wasted can be swept up and chucked in. There are some recipes on the forum somewhere but I think I used 1500lt to 1t urea

 

[robs1]

I used a 2500lt tank with a 2" camlock outlet connected to a petrol powered pump then back into the top of the tank. It only had a standard hatch in the top but it you're careful and hang the bag over the top and cut a small hole it will all go in, do it on some concrete and the little bit that gets wasted can be swept up and chucked in. There are some recipes on the forum somewhere but I think I used 1500lt to 1t urea

We have recently taken our old bulk milk tank out of the dairy was planning on building a hopper over it to hold the urea and let it trickle into the tank with the paddles going

 

[PSQ]

We have recently taken our old bulk milk tank out of the dairy was planning on building a hopper over it to hold the urea and let it trickle into the tank with the paddles going

If its an insulated tank it might have issues with absorbing ambient heat, but then again if you had a plate cooler and a biomass boiler you might be alright!

Dissolving urea in water is endothermic* and will drop the temperature of the solution down to -10C, it takes a lot of ambient heat to warm it back up to 0C for the last of it to melt. Think of it like a bath of ice water, it will eventually warm itself to the temperature of the room it's in, but the warmer the air in the room (or the outside air temperature around the fert tank) the quicker it will warm up.


[* - it's the same reaction you get with a sports ice pack, when you bend it to mix the water and urea inside.]

 

[Andrew K]

Dissolving ordinary urea ,say 5 to 7 kg in 200 Lt sprayed with crop spraying nozzles per htr would this burn from now to June possibly 5 times. Information greatley appreciated thanks

Simplest answer is mix higher strength to 20N and just spray in evenings/night unless its hot [over 20 degrees] plus windy.

 

[robs1]

If its an insulated tank it might have issues with absorbing ambient heat, but then again if you had a plate cooler and a biomass boiler you might be alright!

Dissolving urea in water is endothermic* and will drop the temperature of the solution down to -10C, it takes a lot of ambient heat to warm it back up to 0C for the last of it to melt. Think of it like a bath of ice water, it will eventually warm itself to the temperature of the room it's in, but the warmer the air in the room (or the outside air temperature around the fert tank) the quicker it will warm up.


[* - it's the same reaction you get with a sports ice pack, when you bend it to mix the water and urea inside.]

View attachment 941930

Well that's something I've learnt today, I always thought when you mixed water with chemicals you got heat as part of the reactions as in adding caustic soda to treat straw, that got really hot. Our tank is old school ice bank tech with kids so no insulation and with two agitators should allow ambient air temp to warm it up ok (I hope)

 

[robin banks]

I melted a bit last year as an experiment. Was during summer so water was not too cold starting off. As a trial I dissolved a small 50kg bag of urea in a cut down 200 litre barrel. With no agitation it was going to take forever. So dropped a 2" sump pump in which done the trick. Then sprayed it on with T3 spray was only a few units per acre with standard nozzles and no scorching. The next week I melted more in an ibc and sprayed it with fert nozzles at 30 units of nitrogen an acre with no issues.
Only thing is there was a really nasty grey oily sludge that would float to the top when I melted the urea. Is that normal

 

[PSQ]

Only thing is there was a really nasty grey oily sludge that would float to the top when I melted the urea. Is that normal

Might be a Kaolin clay coating.
I’ve had similar when melting AN and SoP, a horrible greasy gunk that you can skim off with a pond net, horrible stuff.

 

[Barleymow]

Been thinking about doing this for headlands as we have small fields, how do you dissolve it ?

1500 plastic tank cheap submersible pump once ice on outside of tank has gone its mixed 24hrs usually

 

[robin banks]

Might be a Kaolin clay coating.
I’ve had similar when melting AN and SoP, a horrible greasy gunk that you can skim off with a pond net, horrible stuff.

That's the stuff. I see its to make nice strong granules. Should of really got prilled. Getting harder to get cheap prilled here now. Especially with all this protected urea being promoted.