Correlation Assessment of Environmental and Energy Features of Wastewater Treatment Plants Towards Circular Economy

Wastewater treatment plays an important role in ensuring ecological safety for water bodies. The achievement of the standard quality of wastewater treatment is being fulfilled through the introduction of the best available techniques. However, the process of wastewater treatment and sludge utilization itself is quite energy intensive. In the course of investment program planning and implementation, corporate managers and local authorities often focus on individual tasks such as how to improve the wastewater treatment quality or to improve energy efficiency; these factors are, however, however interrelated. Achieving the standard quality of wastewater treatment through the introduction of best available techniques and an increase in the number of technological stages usually leads to an increase in the overall energy consumption of the facilities. The hypothesis of the research suggests that the performance assessment of wastewater treatment plants needs mutual accounting of two main factors: wastewater treatment quality and energy efficiency. The main purpose of this work is to develop a methodological approach for assessing the effectiveness of wastewater treatment plants on the way towards the implementation of circular economy principles, followed by its trial application. The authors proposed a methodological framework that consists of three stages: (1) assessing the quality of wastewater treatment, (2) assessing energy efficiency, and (3) constructing a sustainability index on a correlation matrix. The outputs of the operation activities of wastewater treatment plants in Yekaterinburg for 2015-2018 were used for methodological framework approbation. The results of the investigation develop existing knowledge regarding the assessment of the effectiveness of management at treatment facilities and confirm the research hypothesis: the obtained values of the sustainable index correlate with the technical condition of the facilities both in terms of the achievement of the standard treatment quality the energy efficiency of the technological process. The practical significance of the study lies in the creation of a convenient and simple management tool for assessing the current success of wastewater treatment plants and progress in implementing successful circular economy practices. The proposed approach can be used as an element of environmental and economic assessment in the energy sector.