Division BAT 35 In order to reduce the consumption of treatment chemicals and the consumption of energy and to reduce emissions of treatment chemicals, BAT is to optimise the wood charge of the vessel and to avoid trapping of treatment chemicals by using a combination of the techniques given below.
United Kingdom
| Technique | Description | Applicability | |
|---|---|---|---|
| (a) | Separation of wood in packs by spacers | Spacers are placed at regular intervals in the packs to facilitate the flow of treatment chemicals through the pack and the draining after treatment. | Generally applicable. |
| (b) | Sloping of wood packs in traditional horizontal treatment vessels | Wood packs are inclined in the treatment vessel to facilitate the flow of treatment chemicals and the draining after treatment. | Generally applicable. |
| (c) | Use of tilting pressure treatment vessels | The whole treatment vessel is inclined after treatment so that excess treatment chemicals drain easily and can be recovered from the bottom of the vessel. | Only applicable to new plants or major plant upgrades. |
| (d) | Optimised positioning of shaped wood pieces | Shaped wood pieces are positioned so as to prevent trapping of treatment chemicals. | Generally applicable. |
| (e) | Securing wood packs | The wood packs are secured inside the treatment vessel in order to limit the movement of wood pieces which could change the structure of the pack and reduce the impregnation efficiency. | Generally applicable. |
| (f) | Maximisation of the wood load | The wood load in the treatment vessel is maximised to ensure the best ratio between the wood to be treated and the treatment chemicals. | Generally applicable. |