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[Ersilcoff]

Hi.
I was hoping someone could help a poor chemist like myself with limited ChE knowledge.
I am trying to estimate the viability of a new project. In order to do so I need to estimate the price of an industrial distillation process.
Are there some rule of thumb guidelines that I can use to estimate the process price as a funtion of:
Scale
Boiling Point
Plates (I probably dont need less than five and possibly 1)
Equipment (batch reaction vs continuous column, maybe WFE)
and other parameters that may be relevant.
Any help you could provide or any resources you could show me would be ver helpful.
E.

[Art Montemayor]

Ersilcoff:

Unfortunately, there are no magical rules of thumb, equations, graphs, or wands that can be used to come up with a credible, and worthwhile capital cost estimate for a distillation unit based on what you have as starting, basic data. I’ve seen so many so-called “estimates” in my 51 years of practice and most have been either a joke, preposterous, or simply not worth the time to read.

What you have is generalized basic data and this is of little worth, except to start a detailed process study that would involve a process calculation and preparation of the major equipment Data Sheets. With that kind of information you could (possibly) arrive at an estimate that could be +/- 50% accurate, depending on the accuracy of the basic data and the degree of detail(s). I have seen even this type of estimate go to 100 to 150% off in error. So it basically depends on:

• What you are willing to accept as a % of error:
• Where you are located (what are the local costs, and market conditions);
• The materials of construction;
• The degree of scope and design information;
• The amount of time (man-hours) you can afford;
• The basic Unit Operations definition and any difficulties;
• Any process deviations or capacity controls involved;
• Local safety and health regulations;
• Etc., etc.

But if you only need a “WAG” type of estimate, then we can throw anything out on the table that resembles an estimate.

Any capital cost estimate is going to cost time and money – no matter what the size, quality, or type. It all depends on your needs and what you are willing to pay for it.