Full Name: Pham AnhTu
Class: K4
ID: CTTT13210158
SELF STUDY #1
1, Interpretation of Shell- OMEGA technology for Ethyleneglycol (EG) manufacturing
MEG is produced via EO, which is manufactured in an integrated plant utilizing Shell EO technology. An important feature of the process is the negligible production of diethylene glycol (DEG) and triethylene glycol (TEG), which occur as byproducts in other ethylene glycol production processes.
EO is produced by reacting ethylene with oxygen over a silver-based catalyst. These EO catalysts are characterised by several performance factors, including selectivity, activity, productivity and stability. One of the most important measures of an EO catalyst’s performance is its selectivity, which is the ratio of ethylene converted to EO to the total amount of ethylene reacted.
Conventionally, monoethyleneglycol (HOC2H4OH) is produced by the controlled hydrolysis of ethyleneoxide (C2H4O). The monoethylene glycol product is also able to react with ethylene oxide to give diethylene glycol, and so on; sequential reaction with ethleneoxide is how poly(ethylene glycol) is produced. Due to monoethylene glycol`s high boiling point, purification by distillation is energy intensive.
C2H4O + H2O → HOC2H4OH
In the OMEGA process, the ethylene oxide reacts with carbondi oxide (CO2) to yield ethylene carbonate (C3H4O3). Ethylene carbonate is subsequently hydrolyzed to monoethylene glycol and carbondioxide. The carbondi oxide is released in this step again and can be fed back into the process circuit. This process is 99.5% selective for monoethylene glycol.
C2H4O + CO2 → C3H4O3
C3H4O3 + H2O → HOC2H4OH + CO2
Ethylene and oxygen are fed to a multi-tubular reactor, forming EO. This exothermic reaction, conducted in fixed beds in the reactor tubes, occurs in the gaseous phase with the use of a silver catalyst supported on alumina. Steam is generated by the heat of reaction.
The reactor product stream is fed to the EO absorber for lights removal by water quenching. Part of this gaseous overhead stream is recycled to the reactor, while the other part is sent to a carbon-dioxide-removal unit composed of an absorber and a stripper. In this unit, CO2 is separated to be used in ethylene carbonate production.A diluted EO stream removed from the absorber is fed to the EO stripper, where it is concentrated and recovered in the overheads. The crude EO stream is condensed. Residual light gases are recovered from it and recycled to the reactor. The resulting EO stream is directed to the next section.
Ethylene oxide is reacted with CO2, forming ethylene carbonate, which is then hydrolyzed to form MEG and CO2. Both reactions are carried out in the liquid phase using homogeneous catalysts.CO2 streams from the reaction steps are recycled to the ethylene carbonate reactor. MEG is purified in two distillation columns where water is removed, leading to the final MEG product. The catalyst is separated and recycled to the ethylene carbonate reactors.
2, Draw block diagram of EG production from ethylene by hydration of ethylene oxide
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3, Draw block diagram of EG based on Shell OMEGA technology by ethylene carbonation using CO2.
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Interpret production of Ethyleneglycol (EG) from synthesis gas via dimethyl oxalate
The CO and H2 in the feed syngas are separated
The recovered CO is fed to the carbonylation reactors along with a recycled stream from the nitrite regeneration section that contains an intermediate (methyl nitrite). Methyl nitrite reacts with CO to produce the intermediate DMO and nitric oxide (NO) in Carbonylation reactor
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The DMO-rich stream is fed to the Hydrogenation reactors along with H2 recovered from the syngas feed. DMO reacts with H2 to produce the final product, ethylene glycol and methanol. The product stream from the hydrogenation reactors is partially condensed, and the condensate is directed to the Purification section

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The purification system consists of a series of distillation steps to separate fiber-grade ethylene glycol from methanol and other byproducts formed during DMO hydrogenation. Methanol is recovered from an intermediate distillation column and is recycled to the nitrite-regeneration section.
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The top product stream from the nitrite reactor is partially condensed to remove most of its water and the resulting methyl-nitrite-rich stream is recycled to the carbonylation section. The reactor bottom product is directed to a water-removal distillation column
Reactor in Carbonylationproces
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Comment on advantage and disadvantage of hydration, carbonylation and Shell OMEGA technologie
This is a faster method of producing Ethanol
It is a continuous process
This new technology that it selectively produces MEG and minimizes the production of diethylene and triethylene glycols
Draw block diagram of EG from synthesis gas via dimethyl oxalate:
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