7 replies to this topic

[aysgldl]

Hi everyone,

 

I need to calculate the temperature of hexene in the line over time.

 

I have to find out what the maximum temperature in the line would be if left for 2-3 days?

 

Is there any spread sheet or website that I can get some help? 

 

Thanks in advance!

[Pilesar]

Is there any reason you believe the final temperature to be different from the ambient temperature?

[Mahdi1980]

Describe your case in detail. Your question is unclear.

[aysgldl]

Is there any reason you believe the final temperature to be different from the ambient temperature?

 

Pipeline is made of carbon steel and sitting outside. So, getting solar radiation will increase the heat on the pipe and the product in it.

[aysgldl]

Describe your case in detail. Your question is unclear.

 

I am working on a hexene storage project. We want to see in case the product needs to stay in the pipeline for any reason maybe for 2-3 days, what would be the max temp the product will be getting, and how we calculate it. Need to consider time, solar radiation, pipe material itself I guess. That is all I know anyway.

 

I know the ambient temp where the pipeline is settled.

Hexene operating temp

time: 3days

Pipe diameter

Pipe length

Pipe material: carbon steel

I guess, I need to consider wind speed as well which I know approximately 140mph in the area

[Mahdi1980]

When you are asked to describe the details, the ambient temperature ( normal and Maximum ) and humidity to be indicated.

Also, the length of pipeline in which Hexene might be blocked as well as its diameter are important.

 

Anyhow, in worse case, the maximum temperature is your base. You should solve the heat transfer equations ( Convection and radiation) to find the temperature of hexene in it.

It means that you should consider the temp of fluid inside the pipeline as an unknown parameter and then by guessing  the fluid properties  at an assumed temp. and air properties at the maximum ambient temp and considering the wind speed at that conditions, write the below equations:

1- Force convection between the ambient and fluid associated with the conduction through the material.

2- Radiation between air and fluid .

3- Sum up the above equations

4- solve it for T of fluid( hexene) and find the T

5- compare the obtained Temp. with the T assumed at the 1st step

6- if differences are high, consider the new T as your initial guess and again do the above procedure

 

 

I think you may also need a PSV /  PRV to release the pressure increase of the pipeline due to expansion of your fluid.

[aysgldl]

Mahdi1980:

 

Can you please check your message box? I asked you a question regarding the formulas in there. 

 

Thanks for the great help!

[breizh]

Hi ,

I believe like Pilesar that you will reach the ambient temperature . This should be the basis for your calculation , stagnant system , which may require a TSV .

 

To delay the process , you may consider to insulate the pipe or to paint it in white !

What about  using N2 to flash the pipe?

 

My 2 cents

 

Breizh

Edited by breizh, 20 June 2017 - 06:34 PM.