11 replies to this topic

[Suffian]

Hello all,

 

Do anyone know where to get the standard price for the distillation column. I need it for my Final Year design Project.

 

Thanks so much in advance.

 

[thorium90]

Plant columns dont come in standard prices at least not like you can go into a shop and buy ready made furniture. I've attached a excel file that comes with the book "Analysis, Synthesis, and Design of Chemical Processes" by Turton R., Bailie R.C., Whiting W.B. and Shaeiwitz J.A. Read the chapter on "Estimation of capital costs"

Attached Files

•  CAPCOST_2008.xls   1.83MB   1115 downloads

Edited by thorium90, 27 February 2013 - 10:36 PM.

[Raj Mehta]

HI suffian, 

 

Thorium90 is right, distillation column do not come in ready made packages. many factors are involved in costing of distillation columns, like, column height, diameter, thickness/insulation, supports, trays & downcomer cost etc..The excel sheet he has shared is a good one, I Thank him for sharing the same. 

 

All these factors vary with system requirement and the design and there is no thumb rule for the same. 

 

manually you can calculate this way: 

 

1. from height & diameter of the column calculate, the volume of steel required, multiply it by density of steel and the multiply it by cost of steel /kg. this will give you the final cost of the shell. Repeat the same for top & bottom dish end. 

2. No. of trays * (tray volume*steel density*cost of steel/kg) 

3. same for downcomer. 

4. Estimate whether you require tray or column stiffeners ? 

 

I guess this much of costing is sufficient during graduation stage for a final year project and this costing will comprise of around 90-95% of your column cost.

 

All the best.

 

Thanks

 

Regards,

Raj Mehta 

[thorium90]

Raj, that is not a very accurate way either. One reason is it doesnt take into account stuff like manpower costs or stuff like the difficulty of fabrication. For example, hemispherical heads will cost more than ellipsoidal heads due to the extra effort to form the head. It also doesnt take into account stuff like the internals, brackets, supports, ladder etc. The change in price of steel also may not correspond to a proportional change in its cost. There are also many different grades of steel.. There are also other factors like its pressure, thickness, welding. For example, a trayed distillation column with the same weight as a storage tank will have different costs. I have seen many student reports using your method, but it is a very poor method of estimating capital costs and is never used in reality...

Edited by thorium90, 28 February 2013 - 12:17 AM.

[ankur2061]

Suffian,

 

Refer the following links for online cost estimators including one from Peters, Timmerhaus and West:

 

http://www.mhhe.com/...rs/data/ce.html

 

http://www.matche.co...pCost/Index.htm

 

Regards,

Ankur.

[thorium90]

Ankur, the links, like the first one, don't quite say how they get those values, like how they account for inflation or anything like that. Is there any link or book or journal that it is tied to that might give some explanation?

[ankur2061]

thorium90,

 

I had posted 2 blog entries related to equipment costing where inflation is accounted for based on the cost index of the year under consideration for buying the equipment. Refer the links:

 

http://www.cheresour...-storage-tanks/

 

http://www.cheresour...ost-estimation/

 

Regards,

Ankur.

[Raj Mehta]

Raj, that is not a very accurate way either. One reason is it doesnt take into account stuff like manpower costs or stuff like the difficulty of fabrication. For example, hemispherical heads will cost more than ellipsoidal heads due to the extra effort to form the head. It also doesnt take into account stuff like the internals, brackets, supports, ladder etc. The change in price of steel also may not correspond to a proportional change in its cost. There are also many different grades of steel.. There are also other factors like its pressure, thickness, welding. For example, a trayed distillation column with the same weight as a storage tank will have different costs. I have seen many student reports using your method, but it is a very poor method of estimating capital costs and is never used in reality...

Thorium90,

 

I understand there are many factors involved in costing of a distillation column. I definitely agree with you and I also thank you for highlighting the other factors, which I failed to highlight in my post. 

 

Regards,

Raj Mehta

Edited by Raj Mehta, 01 March 2013 - 09:38 AM.

[xuesongsong]

thanks for sharing all those easy tools for calculating the total cost/price

but also noted the version is quite old（basic on 2007/8)

is there any latest version？

 

with all the best wishes

[thorium90]

Equations dont really get updates... the cepci index is updated though

[chemeng1994]

Hi, I am a 2nd year chemical engineer doing a case study project and I needed to find out the labour costing for a distillation column for both while it is being build and while it is in operation. I know there are some stuff on costing in colesons and richardsons volume 6 but if anyone else could refer me to any useful material it would be greatly appreciated.

[Light]

chemeng1994

 

It would be better if you ask your question in a new post and do not add it to an existing thread as it may create confusion. You can get better replies to your question if you post your question in a new thread.

 

Regards.