| Summary: | The establishment of Emission Limit Values (ELVs), especially in the industrial
sector, is one of the most problematic environmental issues in developing countries.
In addition, industrial effluent limitations should be established regarding the special
characteristics of each sector. In Iran, with a uniform “Wastewater Effluent Standard”,
a scientific methodology for determining ELVs at the sector level is an essential need.
The objective of this study is to present a reliable and pragmatic methodology for
establishing ELV thresholds at the sector level with an emphasis on the Best Available
Technology (BAT) concept. In general, the most common approach for technology
evaluation and ELVs identification, in both developed and developing countries, is
expert judgment. Therefore, this research employs a multi-dimensional approach. A
hybrid Fuzzy multiple-criteria decision-making (FMCDM), consisting of the Analytic
Hierarchy Process (AHP) and the Technique for Order Preference by Similarity to
Ideal Solution (TOPSIS) in combination with fuzzy logic is structured to make use of
the combined benefits of several methods. The modelling framework includes three
main sections that is: a) determining the most appropriate Wastewater Treatment
Technologies (WTTs); b) computing the emission levels associated with the Best
Practicable Control Technology Currently Available (BPT) concept; and c) identifying
the final ELVs based on the results of the two previous sections. Iran’s iron and steel
industry, which constitutes a fundamental sector in the country’s economy, is selected
as the case study. The results obtained indicate that experts have considered the
country-specific information, which consists of the most appropriate WTTs and ELVs
related to BPT, as a reliable reference in their decisions. According to the findings,
corrective measures in accordance with the BAT considerations should be
implemented in many of the plants under consideration and the experts largely prefer
the more advanced WTTs, because of their high system efficiency and compatibility
with environmental impact criteria. This transparent stepwise process has resulted in
defensible country-specific ELVs for the iron and steel industry, which can be
developed for other sectors. As the main conclusion, this study demonstrates that
FMCDM is a systematic and robust operational decision tool for this comprehensive assessment regarding the data availability limitations in developing countries and
emphasises industrial sustainability. This hybrid model of AHP, TOPSIS and Fuzzy
logic offers better results and provides a higher degree of confidence for this
sophisticated judgment. It is a multi-dimensional approach that considers the sector
characteristics; the interaction of the technical, environmental and economic aspects;
and the specific preferences in developing countries.
|
|---|