Cylinders and Extinguishers: $2.70 of Steel, and Why Every Yard Says No

Every scrap yard refuses sealed pressure vessels, and the reason is that shredders throw sparks. Once a cylinder has been professionally purged and the valve removed, it is ordinary steel worth very little: a 20 pound propane grill tank shell is about $2.70 and a disposable helium tank about $2.38. The brass valve off that helium tank is worth $5.28, which is more than twice the shell it came from.

Scrap Price Today market analysis, written from exchange settlement data, mill and refiner pricing practice and published policy documents. Figures are examples; today’s numbers are on the live scrap price board.

That is the honest summary of this whole category. The safety procedure is not optional and the money never justified it in the first place.

Why yards refuse them

Industrial shredders create sparks by design, and any trapped vapour in a cylinder ignites instantly. Municipal collection is no safer: a cylinder crushed in a refuse truck compactor can rupture and release its remaining contents.

So the position is consistent across yards, transfer stations and collection authorities. Yards accept cylinders only after they have been professionally purged, visually verified as empty and physically disabled.

Empty is also not what most people think it is. Every previously used propane tank retains some gas, and simply opening the valve does not verify otherwise.

What each type is worth once it is legal to sell

A garage collection of one propane tank, one helium tank, one extinguisher and four camping cylinders weighs about 55 pounds and is worth about $7.56. Against a trip cost of roughly $30, this material never justifies a journey of its own.

The brass valve line is the one worth reading twice. On a helium tank the valve accounts for about 69 percent of the total value, and it is the part people throw away.

Propane: what to actually do

Do not remove the valve yourself. Removal requires equipment and training to meet fire protection standards, and doing it wrong is a fire and explosion risk. Guidance is uniform on this point.

Do not cut, puncture or drill it. A torch or cutting wheel on a tank that may still hold propane is the specific scenario the warnings exist for.

Do not put it in a bin, skip or dumpster. Compaction is the hazard.

The routes that work, in order:

1. Exchange it. Cages at hardware and grocery retailers take 20 pound tanks, and you leave with a full one.
2. Return it to a propane dealer. Most accept any size at no charge, because the steel has scrap value to them, and some credit a small amount against your next refill.
3. Household hazardous waste. Usually free for residents, and equipped for aging or rusted tanks.
4. Scrap yard, last. Only after a licensed technician has purged and de-valved it.

One pound camping cylinders are the awkward case. Exchange cages will not take them, so household hazardous waste is normally the answer.

Checking whether a tank is empty

Useful, though it does not make a tank safe to cut.

• Weigh it. Compare against the tare weight stamped on the collar, marked TW. If the numbers match, it is empty.
• Warm water down the side. The metal feels cooler where liquid propane remains.
• Listen at the valve. For non-fuel gases, no sound on opening usually means empty.

None of these authorises valve removal. They tell you which route to use, not that you can do the work.

Fire extinguishers

Most are refillable, which is the first thing to check, and certified retailers will service them. They must not go in general waste or recycling.

An extinguisher body is worth $1.85 in steel or $7.65 in aluminium, so the recycling case is thin and the refill case is strong. Municipal guidance typically directs residents to a certified extinguisher retailer or a hazardous waste collection event.

Aerosols, which are the same problem in miniature

Empty steel aerosol cans are accepted by many kerbside programmes and refused by others, and partially full ones are refused everywhere. They are a pressure vessel with a flammable propellant, and they behave the same way in a compactor.

Check locally before adding them to a bin, and never puncture one to prove it is empty. Our page on metal in the recycling bin covers the boundary.

The one cylinder worth handling yourself

Disposable helium tanks are the exception, because the manufacturer publishes a procedure and municipal guidance reproduces it: empty through the valve, unscrew the nozzle, then take it for steel recycling.

Even there, the reward is $2.38 of steel plus a $5.28 valve. Our helium tank page sets the procedure out in full, including what to do when a valve will not open, which is to stop.

The rule that covers everything here

If it held gas under pressure, assume it still does, and let somebody equipped for it make it safe. The metal underneath is ordinary and cheap, and no cylinder in this article is worth an injury.

Our safety article sets out why heat burns are among the three most common injury types in this work, and cutting into a vessel is the shortest route to one.

What this metal pays around the world

Scrap is a global market priced in US dollars, but what reaches a seller depends on trade position, freight to the nearest consumer and how many buyers compete locally. The table below converts the same grade into each market’s own currency and units at the day’s exchange rate, and shows the factor we apply.

Method

Values apply our own board grades to typical shell weights for common cylinder types, documented on the editorial policy page with live figures on the board. Weights vary by manufacturer and specification; weigh your own.

Handling guidance is summarised from published state environmental agency, municipal sanitation and propane industry sources. Requirements differ by jurisdiction, and what one county permits another may fine, so check locally before moving anything.

This is general information rather than instruction for making a pressure vessel safe. That work is for licensed technicians, and nothing here should be read as authorising valve removal, cutting or venting.

Questions people ask

Will a scrap yard take a propane tank?

Only after a licensed propane technician has purged the cylinder and removed the valve. Most yards refuse a sealed tank on sight, because industrial shredders create sparks and any trapped vapour ignites instantly. The empty shell is then ordinary steel worth about $2.70.

Can I remove the valve from a propane tank myself?

No. Valve removal requires specialist equipment and training to meet fire protection standards, and doing it incorrectly is a fire and explosion risk. Published guidance from environmental agencies and the propane industry is uniform on this point.

Where should an old propane tank actually go?

Exchange cages at retailers take 20 pound tanks and give you a full one. Propane dealers usually accept any size free because the steel has value to them. Household hazardous waste is normally free for residents. A scrap yard is the last option and only after purging.

How do I tell if a propane tank is empty?

Weigh it and compare against the tare weight stamped on the collar as TW; matching numbers mean empty. Warm water poured down the side feels cooler where liquid remains. Neither test makes the tank safe to cut or de-valve.

What is a cylinder actually worth as scrap?

Very little. A 20 pound propane shell is about $2.70, a disposable helium tank $2.38 and a steel extinguisher $1.85. An aluminium scuba tank at $26.35 is the highest in the category. A garage collection of typical cylinders weighs 55 pounds and is worth about $7.56.

Is the valve worth keeping?

Yes, where it has been professionally removed. A brass cylinder valve is worth about $5.28, which on a helium tank is roughly 69 percent of the total value and more than twice the shell it came from. It is also the part most people discard.

What should I do with a fire extinguisher?

Check whether it can be refilled first, because most can be, and certified retailers service them. The body is only worth $1.85 in steel or $7.65 in aluminium. It must not go in general waste or recycling; municipal guidance directs residents to a certified retailer or a hazardous waste event.

Can empty aerosol cans go in the recycling bin?

It depends on the programme. Many accept fully empty steel aerosols and some refuse them, while partially full cans are refused everywhere. They are a small pressure vessel with a flammable propellant and behave the same way in a compactor. Never puncture one to prove it is empty.

Frequently asked questions