Spreading Exploding Sulphur!

[tukituki]

Hi there,
Any ag pilots out there seen sulphur blow Up? we were spreading rpr with 17% sulphur in it to day and as I was coming back to the strip there was a black cloud above the super bin.I thought it was the loader truck on fire but my driver said as he went into the bin to get anothor load was a big bang and lot of smoke. The sulphur was not mixed very well with the rpr.Just wondering if anyone had that happen to them?

Tukituki

[SNS3Guppy]

You're spreading sulfur and this is the first time you've heard about this?

[tukituki]

Yes I have heard of sulphur doing its thing but down here (NZ) not usually a problem as we mostly spread Super Phosphate with sulphur mixed in. But our problem with the fert sulphur mix is the fert comany has not done a proper job mixing the sulphur and not dealing with the lumpy bits.My boss is sorting it out with the fert company

[SNS3Guppy]

Probably a static discharge in the case you described. Was it being mixed wet or dry? Dry powders being dispensed from the gate or through a spreader, can be very explosive, especially sulphur. While I haven't seen it, I've worked with others from way back when, who recall cases of it igniting behind them and "chasing" them across the field. I can imagine that to be true.

In a static condition such as a mixing tank, or even in the hopper...watch out! Once it's a dust in the air, it's not just rapidly flammable, but explosive, and can release an enormous amount of energy. Fertalizer, such as amonium nitrate, mixed with sulphur or avgas/jet, can produce a tremendous explosion, or uncontained in the open, a rapid fire. Great care is needed. When you carry those materials, you're carrying around a bomb. Your aircraft is full of ignition sources, as if often the loading pit, with conveyors, pumps, mixers, etc...any one of them could set it off.

[AT502B]

Thankfully we don't have to put out Sulphur down here on the gulf coast:}
Sounds like static is what could be causing it like the previous poster mentioned. What equipment you guys running down in NZ? The reason I ask is one of our old AT402B's with a crew seat ended up down in your neck of the woods.

[tukituki]

Hi there, my old boss has that 402, very pleased with it. Only about 5 402s and 502s here. We do very little aerial spraying in nz. Our main trade is spreading soild fert and lime on to very hilly farms that can't be done with trucks. NZ and Aussie I think are only countries that do this.We fly off airstrips that are usually downhill ie down a ridge so that we can take off down and get speed up fast and we land up the strip.Great for slowing down.Once you get the hang of it its easier than landing on the flat!
Mainly fu24 Fletchers 1 tonne loads, turbine fu24 1.3 tonne and Crescos 2 tonne do the bulk of the work.Plus some Ga200 fatman.Agwagons are nearly finished here as too small.
I fly Fu24, not good to fly and ugly as but they can really get through the work.Can send photo if you want.
Later

[AT502B]

tukituki, thanks for your reply. I'm always amazed how small this ag-flying community is:E
I have seen pics of you Kiwis flying off the sides of mountains- impressive stuff. ALong the gulf coast here it's flat as a table, apart from the odd river and trees. We run 502's servicing rice, cotton mostly.
If you have a pic that would be great, I'll send my address to your PM box.
Later

[SNS3Guppy]

I saw a fletcher when I was living in QLD years ago. Interesting airplane. Never got to fly in one, though.

Dry fertalizer is done in a lot of places, not just NZ and AUS.

I've been using a turbine Dromader the last few years, both the PT6A and Garret versions.