# Commission Implementing Decision (EU) 2016/1032 of 13 June 2016 establishing best available techniques (BAT) conclusions, under Directive 2010/75/EU of the European Parliament and of the Council, for the non-ferrous metals industries (notified under document C(2016) 3563) (Text with EEA relevance), Division BAT 55

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

In order to use energy efficiently during the production of alumina from bauxite, BAT is to use one or a combination of the techniques given below.
Technique
Description
Applicability
a
Plate heat exchangers
Plate heat exchangers allow a higher heat recovery from the liquor flowing to the precipitation area in comparison with other techniques such as flash cooling plants
Applicable if the energy from the cooling fluid can be reused in the process and if the condensate balance and the liquor conditions allow it
b
Circulating fluidised bed calciners
Circulating fluidised bed calciners have a much higher energy efficiency than rotary kilns, since the heat recovery from the alumina and the flue-gas is greater
Only applicable to smelter-grade aluminas. Not applicable to speciality/non-smelter-grade aluminas, as these require a higher level of calcination that can currently only be achieved with a rotary kiln
c
Single stream digestion design
The slurry is heated up in one circuit without using live steam and therefore without dilution of the slurry (in contrast to the double-stream digestion design)
Only applicable to new plants
d
Selection of the bauxite
Bauxite with a higher moisture content carries more water into the process, which increases the energy need for evaporation. In addition, bauxites with a high monohydrate content (boehmite and/or diaspore) require a higher pressure and temperature in the digestion process, leading to higher energy consumption
Applicable within the constraints related to the specific design of the plant, since some plants are specifically designed for a certain quality of bauxite, which limits the use of alternative bauxite sources

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Source: https://www.legislation.gov.uk/eudn/2016/1032/annex/division/1.3/division/1.3.1/division/1.3.1.1/division/bat+55 (the official version)
Page: https://openlegislation.uk/eu-decision-2016-1032/annex/division-1.3/division-1.3.1/division-1.3.1.1/division-bat+55
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.