BVT-Merkblatt zu Abwasser- und Abgasbehandlung

Annexes
Art. 5.7.2.5
§ 1. The quantities of SO 2, SO 3 and acid droplets - expressed in SO 2-equivalent - emitted by
certain plants, must be calculated taking account of the volume of gases emitted during the specific
activities concerned and the average SO 2/SO 3-content measured during the same period.
The determination of the flow rate and of the SO 2/SO 3-content must be performed under the
same conditions of temperature and humidity.
§ 2. Without prejudice to the provisions of article 5.7.1.4 and of chapters 2.5 and 4.4, at one or
several measurement stations located near the establishment in a location which is representative
for the pollution originating from the plant, the following must be monitored:
1. sulphur dioxide immissions, if use is made of the sulphate process for the production of titanium
dioxide;
2. chlorine immissions, if use is made of the chlorination process for the production of titanium
dioxide.
If no immission measuring station as referred to in the first paragraph is provided, measurements
must be made at least 12 times per year of the total quantity of gaseous emissions of sulphur
dioxide and chlorine, respectively, from the production site.
§ 3. From 1 January 1995, unless specified otherwise in the environmental licence and as a
derogation from the provisions of chapter 4.4, the SOx-emissions originating from the dissolution
and roasting phases of the titanium dioxide production must be restricted to a value of no
more than 10 kg of SO2-equivalent per tonne of titanium dioxide produced.
Section 5.7.3. The production of sulphur dioxide, sulphur trioxide, sulphuric acid or
oleum (fuming sulphuric acid)
Art. 5.7.3.1
§ 1. The provisions of this section are applicable to the sulphur dioxide, sulphur trioxide, sulphuric
acid or oleum producing plants referred to in subsection 7.1 of the classification list.
§ 2. For the implementation of these provisions, the "conversion efficiency of SO 2 to SO 3" is
defined as follows:
conversion efficiency =
Art. 5.7.3.2
SO 2(in) – SO 2(out)
________________________
SO2(in)
x 100 (%)
§ 1. If - in view of the gases used as raw material - it is technically possible from the viewpoint
of the best available techniques, the double-contact process must be used for the conversion of
SO2 to SO3. If it proves indispensable, in order to achieve the emission limitations corresponding
to the conversion efficiency values prescribed in § 4 of this article, the emissions of SO2
and SO3 can be further reduced by making use of a fifth contact bed, or by means of equivalent
measures. The use of any alternative process is allowed, providing that such process is at least
equivalent from the perspective of pollution control and in particular providing that it guarantees
the same or higher conversion rates.
§ 2. The single-contact process (without intermediary absorption) is permitted only if gases
with SO2-contents lower than 10 % are processed, or gases of which the SO2-contents are
widely varying. If it proves indispensable, in order to achieve the emission limitations corre-
366 Waste Water and Waste Gas Treatment