Dry Ice

[alanhj]

I have been told that (a) good old Dry Ice is now a thing of the past and (b) Dry Ice itself is no longer available throughout Devon and Cornwall. Are both these statements true?

 

If (a) is true. What is the alternative?

 

If (b) is true. Where in the UK can I get it from?

 

Also if (a) is true. What do Pro Stage Shows and TV Shows do when tons of dry ice can be seen flowing all over the place or is this the alternative stuff?

 

If (a) and (b) are true. Where can I get the alternative stuff from and how much does it cost?

 

And for those of you who don't know, I live in Cornwall.

 

Thanks

[the kid]

a) partly true, if you search there are a few topics about it, it is regarded to be unsafe as there are now other alternatives (See below)

 

b) many places will sell it as labs use it etc it would be that a local producer exists no longer as transport can be interesting. I know my local place can still get Co2 Chips.

 

A) heavy fog/low fog machines, it is done using a smoke machine with a refrigeration unit attached, this can be in the form of a full scale fridge, down to a chamber to put ice in, and if you don't have the budget a cool box with ice in bolted to a smoke machine (have a search and there are directions and pictures about the forum)

[Simon Lewis]

I haven't bought any for a few years, but the local gas supplier did sell it. Have you tried BOC etc.? I can't say if Devon & Cornwall is dry ice free, but would have though that some research or University lab woudl need it from time to time?!

 

I can see the argument for other approaches, but all introduce some element of risk, and the use of cryotanks full of liquid nitrogen introduces quite a few more pages to the risk assessment.

[smalljoshua]

I've had dry ice on a show and I'm firmly in Plymouth. We sourced it from BOC. They just brought it down at the start of the week when they topped up Plymouth Uni's cryo tanks.

 

Josh

[StevieLights]

Check out

www.dryiceuk.com

 

Used them before for "original" dry ice for use in the Le Maitre Peasouper

[Kevin@Wicked]

Low Fog machines are used more frequently for similar effect to Dry Ice (without the storage & H&S issues)

 

JEM Glaciator uses a high powered smoke machine running through a large refridgeration unit to reduce the temperature. - Machines tend to be about £300 per week plus about £45 per 5 litre bottle of fluid.

[csg]

cant really add much more, other to say that some food companies use dry ice for fast freezing and transportation, so I would be surprised if it is totally unavailable in the whole of devon / cornwall.

 

Other than this, I find the le maitre freezefog pro the best option - this only requires 10A supply, is a lot smaller and lighter than glaciator type machines and absolutely hoofs out heavy fog that really does hug the floor, even when dancers etc are moving through it, with no ambient haze problems.

 

Downside is that you need a supply of liquid Co2, either from standard dip tube bottles or from a dewar vessel if you are using large amounts. But, for me, the effect is the closest thing to dry ice, and at least the liquid Co2 is cheaper and easier to store than dry ice, and it does not sublime on its own!

[ACIDMAN]

Try speaking to the guys at http://www.green-gases.com/dryice.htm

 

Don't bother making it yourself as out of a 34kg syphon bottle about 3-5kg's worth won't make solids and each bottle weighs 100kg. A pain to transport and not cheap either !

 

Dry ice travels fine in its insulated polystyrene boxes and does not come under the dangerous goods act. Just secure it in the BACK of your car/van and keep the vehicle well ventilated.

 

And if you're worried about sublimation it will last 2-3 days easily ,in its box, if not longer.

 

Bung it in (or carefully place it in) a Le Maitre peasouper and enjoy !!!

 

And don't get dry ice confused with liquid nitrogen !!!! I used to work with liquid nitrogen and it's a different kettle of fish altogether !!!!!!!!!!!!!!!

[alanhj]

Thanks Guys,

 

As per usual problem solved. Any new people on here, believe me, if the people on this site can't resolve your problem - No one can!! Thanks again.

[OllieDuff]

And don't get dry ice confused with liquid nitrogen !!!! I used to work with liquid nitrogen and it's a different kettle of fish altogether !!!!!!!!!!!!!!!

 

Oh Gods. I want to meet the person that made that mistake: "Yeah, just put on rubber gloves and pick it out by ha-AUGHMYFINGERS!"

 

University science laboratories are a good source if you need dry ice at relatively short notice or on a budget; obviously they won't deliver but BOC or similar can charge such a large amount for shipping that it's sometimes cheaper to go and fetch it yourself. Storage: polystyrene boxes in a cool place will last for a couple of days without losing too much mass.

[Kevne]

I can't remember which theatre it was but they were storing a load of dry ice in a locked container in the yard. One night a load of kids broke into the container and stole some of the blocks. They could have only gotten a few metres before the dry ice had the inevitable effect on their unprotected hands and they dropped the blocks and ran away, cradling their burned fingers.

 

Funniest bit of CCTV footage I ever saw!

[adam2]

Yes do not confuse dry ice with liquid nitrogen.

Dry ice is solid carbon dioxide.

 

Liquid nitrogen is an exceedingly cold liquid, stored at atmospheric pressure in a well insultated container known as a dewar vessel, used to freeze pipes and to preserve things by extreme cold.

Available everywhere, in portable dewar vessels or for large volumes from a tanker.

Liquid nitrogen is not that dangerous, but should not be used without at least basic safety instruction.

The main risks are cold burns, sufocation, and explosion if placed in any sealed container.

NEVER take a dewar of liquid nitrogen into a van or car, use an open truck or a vehicle with open space between the load compartment and the driver.

NEVER take a dewar of nitrogen into a lift with a person, use the stairs, or send it in an empty lift.

 

There is no such thing as liquid carbon dioxide at atmospheric pressure, it exists only as a gas, or if cold enough as a solid at atmospheric pressure.

Cylinders may contain liquid carbon dioxide under great pressure, but when released from the pressure it turns instantly to a mixture of gas and solid.

[csg]

you can get low pressure C02 dewars as well, my freezefog prefers them over the high pressure bottles.

[timd]

you can get low pressure C02 dewars as well, my freezefog prefers them over the high pressure bottles.

 

Not with a liquid in you can't, or at least not below 5 bar. That's the triple point pressure, below which you can get no liquid phase.

 

When handling liquid nitrogen, remove all rings and things of that nature from hands and fingers. If you get it on bare hands, it will generally flow off no problem at all, but if it gets trapped by a ring, you can say goodbye to the finger.

[csg]

I guess they must be at 5 bar then. Im not doubting you are correct, but I know what I get from cryoservice.