Division BAT 55: In order to reduce the amount of organic waste being sent for disposal from the EO and EG plant, BAT is to use a combination of the techniques given below.
United Kingdom
| Technique | Description | Applicability | |
|---|---|---|---|
| a. | Hydrolysis reaction optimisation | Optimisation of the water to EO ratio to both achieve lower co-production of heavier glycols and avoid excessive energy demand for the dewatering of glycols. The optimum ratio depends on the target output of di- and triethylene glycols | Generally applicable |
| b. | Isolation of by-products at EO plants for use | For EO plants, the concentrated organic fraction obtained after the dewatering of the liquid effluent from EO recovery is distilled to give valuable short-chain glycols and a heavier residue | Only applicable to new plants or major plant upgrades |
| c. | Isolation of by-products at EG plants for use | For EG plants, the longer chain glycols fraction can either be used as such or further fractionated to yield valuable glycols | Generally applicable |