Ethylene oxide purification
AssigneesPetron Scientech, Inc., Scientech Associates Inc.
InventorBrian J. Ozero
Life of this patent
Estimating the term…
Abstract
An improved process for the recovery of high-purity ethylene-oxide water feed streams to EO purification and MEG reaction units when both are operating in EO plants that incorporate EO Stripper bypass technology, by installing a second lights stripper to exclusively degasify the diluted EO feed to the MEG reactor, thus permitting the use of additional bypassed (gasified) EO absorbate as the diluent and resulting in a substantial increase in the total amount of EO absorbate that can bypass the EO Stripper.
Claims9
A process for producing purified ethylene oxide (EO) and monoethylene glycol (MEG), the process comprising the steps of:
- a) providing a quenched and alkaline treated and water washed vaporous reaction stream, wherein the quenched and alkaline treated and water washed vaporous reaction stream comprises EO, CO2, formaldehyde, and acetaldehyde;
- b) contacting the quenched and alkaline treated and water washed vaporous reaction stream with water in an EO absorber to produce a first absorbate stream having a first EO concentration in water;
- c) dividing the first absorbate stream into a first portion of the first absorbate stream, a second portion of the first absorbate stream, and a third portion of the first absorbate stream;
- d) feeding the first portion of the first absorbate stream to an EO stripper and contacting the first portion of the first absorbate stream with steam to produce a vaporous EO stream;
- e) feeding the vaporous EO stream to an EO reabsorber and contacting the vaporous EO stream with the second portion of the first absorbate stream to form a reabsorber bottoms stream, wherein the reabsorber bottoms stream has a second EO concentration in water that is higher than the first EO concentration in water;
- f) dividing the reabsorber bottoms stream into a first portion of the reabsorber bottoms stream and a second portion of the reabsorber bottoms stream;
- g) feeding the first portion of the reabsorber bottoms stream to a first lights stripper and contacting the first portion of the reabsorber bottoms stream with steam to produce a first lights stripper bottoms, wherein the first light stripper bottoms has a third EO concentration in water that is higher than the first EO concentration in water;
- h) feeding the first lights stripper bottoms to a high purity ethylene oxide distillation column to produce purified EO;
- i) combining the second portion of the reabsorber bottoms stream and the third portion of the first absorbate stream to produce a second lights stripper feed;
- j) feeding the second lights stripper feed to a second lights stripper and contacting the second lights stripper feed with steam to produce a second lights stripper bottom stream, wherein the second lights bottom stream has a fourth EO concentration in water that is lower than the third EO concentration in water;
- and
- k) feeding the second lights bottom stream to a glycol reactor to produce MEG.
Dependencies are inferred from the claim text.