Division BAT 33 In order to reduce water consumption and emissions to water from the desalting process, BAT is to use one or a combination of the techniques given below.
United Kingdom
| Technique | Description | Applicability |
|---|---|---|
| (i) Recycling water and optimisation of the desalting process | An ensemble of good desalting practices aiming at increasing the efficiency of the desalter and reducing wash water usage e.g. using low shear mixing devices, low water pressure. It includes the management of key parameters for washing (e.g. good mixing) and separation (e.g. pH, density, viscosity, electric field potential for coalescence) steps | Generally applicable |
| (ii) Multistage desalter | Multistage desalters operate with water addition and dehydration, repeated through two stages or more for achieving a better efficiency in the separation and therefore less corrosion in further processes | Applicable for new units |
| (iii) Additional separation step | An additional enhanced oil/water and solid/water separation designed for reducing the charge of oil to the waste water treatment plant and recycling it to the process. This includes, e.g. settling drum, the use of optimum interface level controllers | Generally applicable |