Steam generation for an experiment

In summary, the conversation discusses the best and cheapest way to generate steam for testing purposes. The speaker suggests using a standard American 110v three-prong outlet as a power source for the steam generator, with an intended mass flow of 20-28g per second. They consider using dental sterilization equipment or modifying a stovetop pressure cooker to serve as a steam source. The conversation also delves into the power and current requirements for such a steam generator and suggests using a gas furnace instead. Finally, the purpose of the steam and its volume requirements are mentioned, with a rough estimate of the power needed for the steam generator.
  • #1
manderson99
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What would be the best, cheapest way to generate steam intended for introduction to a device for testing? I would use a standard American 110v three-prong outlet as a power source for the steam generator. All I really need is a steam source with an absolute pressure of 2 atm/202650 Pa/29.39 psi. The intended mass flow out of the generator would be 20-28g.

I've looked at commercial/industrial boilers, but they generally operate at much higher power than the limits imposed by using a standard 3-prong outlet. They're also hauled on the back of trucks and produce much greater quantities of steam than indicated by my needs. I've examined the possibility of using dental sterilization equipment, but such would need modification to serve as a steam source, since they don't generally have any kind of outlet or blow-off valve (that I can tell). There's also the question of whether or not any of them can serve as a steam source for any non-trivial amount of time.

All I'd really need is a reservoir with a blow-off valve to maintain maximum internal pressure of 2 atm, a pressure gauge, and an outlet. I could tailor a throttle plate to control flow through the outlet. Something as simple as a hot plate could provide heat for the reservoir. Maybe I should take a stovetop presure cooker to a shop and have them modify it or something? I know typical pressure cookers have at least one blow-off valve to maintain pressure, though the valve might need to be replaced unless it's designed to maintain an absolute pressure of 2 atm.
 
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  • #2
Mass flow of 20-28 gram per what time?
(needed to estimate the electrical power)
 
  • #3
Let's see here. Steam at 30 psig will be about 275F. To heat an ounce of 70F water (29g) to 30 psig steam in a minute will require 35 kW or about 300 amps of 117 V AC power (I am doing this from the top of my head - I may not have the correct power numbers). The volume of one ounce of 30 psig steam is about 0.56 cubic feet. Do you need steam or will compressed air work in your experiment?

Small steam generators are available commercially, but more information is needed regarding requirements.
 
  • #4
Sorry I meant to specify, 20-28g per second.

And the gauge pressure (assuming standard 1 atm barometric pressure) would only need to be ~15 psi. That would be ~30 psi absolute pressure. 29.7 psi actually . . .

Vedward said:
Let's see here. Steam at 30 psig will be about 275F. To heat an ounce of 70F water (29g) to 30 psig steam in a minute will require 35 kW or about 300 amps of 117 V AC power (I am doing this from the top of my head - I may not have the correct power numbers). The volume of one ounce of 30 psig steam is about 0.56 cubic feet. Do you need steam or will compressed air work in your experiment?

It would need to be steam. Your numbers look okay to me, though the pressure would be lower than that. 300 amps is more than I could pull off a standard 3-prong outlet. I would have to build steam in advance, I suppose, and that complicates things.

Or I'm going to have to settle on lower steam pressure.

Small steam generators are available commercially, but more information is needed regarding requirements.

What other information would you need?
 
  • #5
manderson99 said:
Sorry I meant to specify, 20-28g per second.
Oh my, that is just not possible with a standard outlet. It would need 60 times the power and the current that Vedward calculated.

Two liters of water per minute into 30 psi steam! Just compare with your ordinary tea water cooker. How long does it take to boil away one liter of water at atmospheric pressure? And those things are the appliances that have the highest power ratings in homes.
 
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  • #6
OK - your demand is about 100 kg/hr (220 lbs/hr) of 30 psig steam. If you don't want to use a gas-fired boiler, you will need to use a 480 V 3-phase power source. These are available but you will also need water treatment and other support systems.
 
  • #7
Sorry, I meant 15 psig steam. I'll have to pull out my data sheets to confirm the boiler capacity, but this is not a small, tea kettle requirement. This will be a $7,000 US installation.
 
  • #8
Back of napkin estimate... I'm old and still use English units
is 28 grams still about an ounce?
Rule of thumb : one BTU per second is within ~5% of a kilowatt ; 3412.7 BTU/kwh / 3600sec/h = 0.948 BTU/kw⋅sec
~1200 btu/lb X 1/16 lb/sec = 75 BTU/sec / 0.948 BTU/kw⋅sec = ~79 kw

is that about what the SI guys estimated?

79 kw at 120 volts is 658 amps.

Water is amazing stuff isn't it?

old jim
 
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  • #9
Do you have a natural gas hookup? It would probably be cheaper and easier to get a gas furnace installed than try to upgrade your electrical system. Even if you have to build a chimney.

BoB
 
  • #10
I'm curious about the device that needs all this steam?
 

Related to Steam generation for an experiment

1. What is steam generation and why is it important for experiments?

Steam generation is the process of producing steam from water. It is important for experiments because steam is a versatile and commonly used medium for heat transfer, sterilization, and chemical reactions.

2. How is steam generated for experiments?

Steam can be generated using various methods such as boiling water, using a steam generator, or passing water over a heated surface. The method used will depend on the specific experiment and the required amount of steam.

3. What factors can affect steam generation in an experiment?

The rate of steam generation can be affected by factors such as the temperature and pressure of the water, the size and shape of the steam generator, and the type of fuel used for heating.

4. What safety precautions should be taken when working with steam generation in experiments?

It is important to follow proper safety procedures when working with steam generation, as it involves high temperatures and pressure. This may include wearing protective gear, monitoring the equipment closely, and having a clear understanding of emergency shutdown procedures.

5. How can steam generation be optimized for efficient use in experiments?

To optimize steam generation, it is important to properly maintain the equipment and regularly check for any leaks or malfunctions. Additionally, using high-quality water and properly controlling the temperature and pressure can help improve efficiency.

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