2 replies to this topic

[cflzif]

Hi,
I am a senior Chemical Engineering student and I'm yet to experience real world chemical engineering challenges. This being said I have few questions. I am trying to design a chemical plant to produce ethylene glycol. Di-ethylene glycol and Tri-ethylene glycol are its side products. I want to size some evaporators, distillation columns and heat exchangers. But I am not aware of sizes for these unit operations in industry. In other words what is common size of evaporator or distillation column in real world? I don't want to throw in some some random HYSYS number and want to be as realistic as possible so if you have anything to share from your experience, I will appreciate your help.
Also any suggestions for Ethylene glycol production will be very helpful. This is for my design project.
Thanks in advance.

[ankur2061]

cflzif,

The process of ethylene glycol production via the ethylene---->ethylene oxide----->ethylene glycol process using air oxidation of ethylene and subsequent hydrolysis of ethylene oxide to ethylene glycol with by products of Di-ethylene glycol and Tri-ethylene glycol is a very common process and you will find a lot of information on the internet including technical papers, project reports and design thesis.

What you need to do is decide the capacity of your ethylene glycol plant based on the demand and supply forecast in your region or nation and the unit cost of production of ethylene glycol. You may start with some figure and subsequently tune the capacity to match the economics of production.

As far as equipment sizing is concerned there are no magic numbers for the size of the various equipment and you will have to put all your efforts to size the equipment. As a student it is not expected that you will get it right the first time. You will be revising and reworking your project till the ethylene glycol production is economical for your design and the optimum equipment sizes have been achieved.

Regards,
Ankur.

[cflzif]

Hi Ankur,
Thank you for your email. I am using the method of hydrolysis of ethylene oxide too. But my goal is to minimize Di-ethylene and Tri-ethylene glycol production as much as possible. For this I am increasing water input into the reactor as this will increase water to oxide ratio. But this will increase my heat duty requirement and utility cost too. Do you have any suggestions? As of now my design consists of three evaporators to remove water (all of which gets recycled back into the reactor) and three distillation columns for purification of products. Please let me know.
Thanks again.