Need advise on using silo tanks - Is there anyway to discharge the air rapidly from the tank after it has been pressurised in addition to using the dump valve? Currently have to top up the tank after the first loading (Quarry want to maximise the loads going out - we load via the lids) which means pressurising the tank to spread the product out/then adding more product and the only way of getting air out that i have been shown is via the dump valve which does not empty the tank completely and even if you go to the open the lid 15-30 minutes after the tank still has pressure and every operator manual i have read says never open the lid if the vessel is under pressure.
Iâve never operated a silo tank, I have however compressed loads off in a traditional chemical tanker and despite me being a natural cowboy in most things Iâd warn very much against short cuts involving pressurised air. IMO there is no safe way to dump the air other than approved methods. It WILL bite you in the bum seriously at some point if you do attempt it.
I understand your frustration mate, but certain things you cannot mess with.
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Have to agree with above, assuming your not owner driver, do it the way the boss / procedure says. They may want loads out quicker but thatâs the bossâs issue not yours.
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Wanting âloads out quickerâ sounds like an accident waiting to happen, and when it does itâll be someone like yourself on the receiving end, and it will have been caused by some numpty in an office with insufficient knowledge of the dangers of pressurized gases, but guess who will be taking the blame?
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Works the other way round too. Was once at Widnes tank wash and had washed a barrel so went for some breakfast. A young bloke came and sat near me and there was a loud âTHUNGâ. I asked him if he had had a hot wash on his barrel he said yes. I asked him if he had closed his lids. We went outside and I told him to open his discharge valve and there was a loud shriek from the valve. The tank looked fine but that was only the lagging.When the valve stopped screaming we went on top and opened the lid and the tank had imploded. As the steam condensed inside it formed a vacuum and the tank collapsed.
Used to pull old demountable powder tanks that had a manual vent valve at the back. Only problem was if you opened the valve too wide it plugged up with ice. Gas tankers do the same.If you tried to empty the tank too fast the product turned from gas to solid. The CO2 I used to carry turned into a plug of dry ice.
Dangerous bloody things.
Would you speed if the boss wanted deliveries done quicker? Decompress safely, as youâve been shown. Iâm not sure what a silo road tank is, but i have used what we call pneumatic tanks, where the product is loaded through the top hatches and unloaded via a hose using compressed air. Donât muck around with compressed air, it can kill.
Thatâs just a minor problem, unless you really have an urge for decapitation.
I had a silo tank many moons ago, loaded at the top and pressure emptied at the bottom, but we never had a reason to open the lid under pressure and never saw any advice not to. I suppose it is common sense really.
Thats what really pses me.Used to go for the tanker training every 5 years and it was the same old same old. All legislation and no training. Lad sat next to me at last ârefresherâ said when do they bring the tanker to show us how to load and unload a barrel. I said they dont. He asked so how do I learn? You work for nothing for a couple of weeks with a man who knows what he is doing (hopefully} and he shows you the ropes. Bloody ridiculous. Maybe if you got a job for (in my day) ICI or Hargreaves you got the training. I got a job with a tanker firm that pulled for Huktra and the bloke showed me what to do.So many things in the job you dont even think about will kill you. Once taking a sample at kasner kelner in Runcorn and a frenchman pulled up behind me.
I put on the respirator before I opened the lid to drop in the sample jar he didnt. It was a Chlorine based solvent I had on and one breath could kill you.Dont know what he had on but he opened the lid and he fell off the barrel.There is some nasty crap in those road barrels eg cyanide,oleium (98% sulfuric acid) Phenol etc. One fk up and it aint good.
Have you had any training on the use of pressurised vessels ?
If not keep away. They are a bomb waiting to go off. 1 bar (14psi) spread over a tank internal area of 26 square meters is one world of hurt if you get it wrong.
If youâre working with dangerous goods, there is a legal requirement for your employer to provide a minimum amount of practical training, this should be nothing less than 1hr 30" (2 x 45 minute Training Units, as ADR is calculated). It is not the responsibility of the ADR course provider to deliver this training.
I would hope any decent tanker employer would provide far more than just 1.5 hours.
Do it âby the bookââŚand stuff the âwanting more loads outâ.
I know it was different âback in the dayâ but I fronted up to Mr. Watts at K & M one morning to ask if there was a job going. He said âhave you ever driven a powder tanker?â I said ânoâ he said âdo you want to learn?â I said âyesâ, he said âsee that white and orange Foden artic over there?â âWell that is your motor, and the driver of the identical one alongside it will show you what to doâ.
I said âthank you very muchâ and, within 10 minutes or so I was a fully trained tankee. 
Crikey, ten minutes isnât long enough to walk around and familiarise oneself with the controls.
We only carried three different (dry) products, but each were unloaded differently.
What used to scare me with the demountable powder tanks was tipping the bloody things.Once see one go over at Mullards in Padiham full of feldspar. Must have loaded it wet and it pulled the trailer straight over.