Division BAT 5 In order to reduce fresh water use and generation of waste water, BAT is to close the water system to the degree technically feasible in line with the pulp and paper grade manufactured by using a combination of the techniques given below.
United Kingdom
| Technique | Applicability | |
|---|---|---|
| a | Monitoring and optimising water usage | Generally applicable |
| b | Evaluation of water recirculation options | |
| c | Balancing the degree of closure of water circuits and potential drawbacks; adding additional equipment if necessary | |
| d | Separation of less contaminated sealing water from pumps for vacuum generation and reuse | |
| e | Separation of clean cooling water from contaminated process water and reuse | |
| f | Reusing process water to substitute for fresh water (water recirculation and closing of water loops) | Applicable to new plants and major refurbishments. Applicability may be limited due to water quality and/or product quality requirements or due to technical constraints (such as precipitation/incrustation in water system) or increase odour nuisance |
| g | In-line treatment of (parts of) process water to improve water quality to allow for recirculation or reuse | Generally applicable |
The BAT-associated waste water flow at the point of discharge after waste water treatment as yearly averages are:
| Sector | BAT-associated waste water flow |
|---|---|
| Bleached kraft | 25 – 50 m3/ADt |
| Unbleached kraft | 15 – 40 m3/ADt |
| Bleached sulphite paper grade pulp | 25 – 50 m3/ADt |
| Magnefite pulp | 45 – 70 m3/ADt |
| Dissolving pulp | 40 – 60 m3/ADt |
| NSSC pulp | 11 – 20 m3/ADt |
| Mechanical pulp | 9 – 16 m3/t |
| CTMP and CMP | 9 – 16 m3/ADt |
| RCF paper mills without deinking | 1,5 – 10 m3/t (the higher end of the range is mainly associated with folding boxboard production) |
| RCF paper mills with deinking | 8 – 15 m3/t |
| RCF-based tissue paper mills with deinking | 10 – 25 m3/t |
| Non-integrated paper mills | 3,5 – 20 m3/t |