# Commission Implementing Decision (EU) 2017/2117 of 21 November 2017 establishing best available techniques (BAT) conclusions, under Directive 2010/75/EU of the European Parliament and of the Council, for the production of large volume organic chemicals (notified under document C(2017) 7469) (Text with EEA relevance), Division BAT 69:: In order to reduce the load of nitrite, nitrate and organic compounds discharged from the DNT plant to waste water treatment, BAT is to recover raw materials, to reduce the waste water volume and to reuse water by using an appropriate combination of the techniques given below.

Extent: E+W+S+N.I.

Technique
Description
Applicability
a.
Use of highly concentrated nitric acid
Use highly concentrated HNO3 (e.g. about 99 %) to increase the process efficiency and to reduce the waste water volume and the load of pollutants
Applicability to existing units may be restricted by design and/or operational constraints
b.
Optimised regeneration and recovery of spent acid
Perform the regeneration of the spent acid from the nitration reaction in such a way that water and the organic content are also recovered for reuse, by using an appropriate combination of evaporation/distillation, stripping and condensation
Applicability to existing units may be restricted by design and/or operational constraints
c.
Reuse of process water to wash DNT
Reuse process water from the spent acid recovery unit and the nitration unit to wash DNT
Applicability to existing units may be restricted by design and/or operational constraints
d.
Reuse of water from the first washing step in the process
Nitric and sulphuric acid are extracted from the organic phase using water. The acidified water is returned to the process, for direct reuse or further processing to recover materials
Generally applicable
e.
Multiple use and recirculation of water
Reuse water from washing, rinsing and equipment cleaning e.g. in the counter-current multistep washing of the organic phase
Generally applicable
BAT-associated waste water volume: See Table 9.2.

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Source: https://www.legislation.gov.uk/eudn/2017/2117/annex/division/9/division/9.2/division/BAT+69 (the official version)
Page: https://openlegislation.uk/eu-decision-2017-2117/annex/division-9/division-9.2/division-BAT+69
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.