processes Review Aeration Process in Bioreactors as the Main Energy Consumer in a Wastewater Treatment Plant. Review of Solutions and Methods of Process Optimization Jakub Drewnowski 1,* , Anna Remiszewska-Skwarek 1, Sylwia Duda 2 and Grzegorz Łagód 3 1 Faculty of Civil and Environmental Engineering, Gdansk University of Technology, Narutowicza 11/12, 80-233 Gdansk, Poland;
[email protected] 2 Institute of Agrophysics, Polish Academy of Sciences, 20-290 Lublin, Poland;
[email protected] 3 Faculty of Environmental Engineering, Lublin University of Technology, 20-618 Lublin, Poland;
[email protected] * Correspondence:
[email protected]; Tel.: +48-58-348-63-62; Fax: +48-58-347-24-21 Received: 31 March 2019; Accepted: 16 May 2019; Published: 24 May 2019 Abstract: Due to the key role of the biological decomposition process of organic compounds in wastewater treatment, a very important thing is appropriate aeration of activated sludge, because microorganisms have to be supplied with an appropriate amount of oxygen. Aeration is one of the most energy-consuming processes in the conventional activated sludge systems of wastewater treatment technology (may consume from 50% to 90% of electricity used by a plant), which makes it the most cost-generating process incurred by treatment plants. The paper presents the construction of aeration systems, their classification as well as parameters and factors that significantly affect the aeration process e.g., oxygen transfer efficiency, diffuser fouling, methods of dealing with diffuser fouling, diffuser selection. Additionally, there are briefly presented “smart control” systems in wastewater treatment and effect of application control strategy based on Supervisory Control and Data Acquisition system connected with the decrease in the energy consumption for aeration of bioreactors with activated sludge.