Jump to content



Featured Articles

Check out the latest featured articles.

File Library

Check out the latest downloads available in the File Library.

New Article

Product Viscosity vs. Shear

Featured File

Vertical Tank Selection

New Blog Entry

Low Flow in Pipes- posted in Ankur's blog

Product Loss From Venting

vent pressure loss co2 liquid co2

This topic has been archived. This means that you cannot reply to this topic.
7 replies to this topic
Share this topic:
| More

#1 jmisto

jmisto

    Brand New Member

  • Members
  • 3 posts

Posted 03 June 2016 - 06:50 PM

I am a restaurant owner with a 500lb liquid co2 tank similar to the one shown here: http://www.nuco2.com...ts/xactco2.html

 

I tried to search for my answer on this forum but I am not in the industry and it all might as well be in Latin. So I though I would try the direct approach...

 

This tank is filled by a company on a monthly basis. Last month I was closed for renovations after getting the tank completely topped off. The company just sent me a bill for 77lbs of CO2 from when we were closed. I checked the entire line and there is not a single leak. When I asked a company rep they said that it is probably because the tank vents off pressure now and then. That seems like a large amount of product loss for venting off pressure in 30 days.

 

Can someone tell me:

 

1) What is the normal amount (in lbs) a 500lb liquid CO2 tank would vent off in a month? 

2) Is it even the CO2 that is venting or just air pressure?

3) Is it a viable excuse by the company or is something else going on? 

 

I live in Pennsylvania at 525 feet above sea level with the current temperature around 65-75 degrees. The tank is in an enclosed area and does not sit in direct sunlight (just in case that is a factor.)

 

Thank you.



#2 Bobby Strain

Bobby Strain

    Gold Member

  • Members
  • 3,526 posts

Posted 03 June 2016 - 07:27 PM

I would pay the bill and concentrate on good service and food. Sounds like you have had this supplier for a while with no complaints.

 

Bobby



#3 latexman

latexman

    Gold Member

  • Admin
  • 1,670 posts

Posted 04 June 2016 - 06:18 AM

I would suspect the construction guys drinking the draft beer.  Was your beer tab more than $0 that month too?



#4 proinwv

proinwv

    Gold Member

  • ChE Plus Subscriber
  • 391 posts

Posted 06 June 2016 - 09:31 AM

You could have the relief valve pressure setting checked. If it is low, then it would vent more. It is prudent to keep the tank in a shaded location.

 

If you had a scale with a 500+ lb capacity, you could observe the loss over a time period when you were not operating and extrapolate that.

 

What is the value of 77lb of gas? Is it worth the investigation?



#5 AlertO

AlertO

    Gold Member

  • Members
  • 194 posts

Posted 06 June 2016 - 08:33 PM

Jmisto

 

I will not give you much technical theory because i think you are not familiar to the technical words, just only make you clearly understanding about your tank. So, the following information may help you;

 

1. Your tank must be installed with a relief device which will protect the tank from overpresssure.

2. The pressure in the tank can be varied from any external heat and if the pressure is higher than the set point, some CO2 will be released.

3. The external heat can be from either ambient temperature change or solar radiation (direct sunlight). it's important to keep the tank at shade location as proinwv mentioned.

4. The unexpected venting can be happened, but the good tank design should have no or minimum venting.

5. Raise this problem to the technical support of your CO2 supplier by email or telephone. See how they response with your problem. if they are inattentive, consider to change the CO2 supplier. Because inadvertent venting can be considered as hazard espectially in closed room which directly relates to the safety of your staff.



#6 jmisto

jmisto

    Brand New Member

  • Members
  • 3 posts

Posted 06 June 2016 - 09:25 PM

@proinwv the value is $35/month and I was never made aware of "product venting" to the tune of $400/year. Considering the company has 150,000 customers world wide that is a lot of cash out of thin air and into their pockets!

@AlertO thank you for the info. I am following up with the company but so far I am getting the impression I already know more than they do thanks to you guys.

and @Bobby Strain my food and service are award-winning... if your advice is to pay every bill without questioning it I would like your address. I want to send you a bill of service for this response  :)​ 



#7 Bobby Strain

Bobby Strain

    Gold Member

  • Members
  • 3,526 posts

Posted 06 June 2016 - 10:54 PM

jmisto,

     I'm happy that you are taking care of your clientele. And you probably use the CO2 to deliver beer and other beverages. And I am a true connoisseur of good brew! If you send a bill, my wife will open it, peruse it, and file it in the kitchen file. I think that you use the CO2 from the vapor space. The contents are primarily cold liquid. As you withdraw the vapor, the liquid vaporizes to replace it and thus cools the tank contents.In this manner,the container will normally not vent. However, if the tank sits idle without vapor withdrawal, the contents continue to heat, raising the pressure of the contents until the protective device releases some of the vapor. So, what you are observing is the intended behavior. Without this venting the tank will eventually reach a pressure that will rupture the tank. So you supplier is not trying to make a $. He is simply complying with legal requirements that assure you of a safe product.

 

Where is your restaurant? I like good food and beer, both at home and dining out. And I hope that this forum has been helpful to you.

 

Bobby



#8 jmisto

jmisto

    Brand New Member

  • Members
  • 3 posts

Posted 07 June 2016 - 10:00 PM

Bobby, That pretty much explains everything, thank you it was a big help. Now I CAN go back to worrying about the service and food! I have several in Pennsylvania but the one to which I was referring is in Wilkes-Barre, PA. Thanks again!






Similar Topics