Short‐term Influence of Two Types of Drilling Fluids on Wastewater Treatment Rate and Eukaryotic Organisms of Activated Sludge in Sequencing Batch Reactors

Abstract

This work presents the results of studies on the impact of spent drilling fluids cotreated with municipal wastewater on the rate of the wastewater treatment process and the structure of the community of eukaryotic organisms inhabiting an activated sludge. The studies were conducted under laboratory conditions in sequencing batch reactors. The effect of added polymer-potassium drilling fluid (DF1) and polymer drilling fluid (DF2) at dosages of 1 and 3% of wastewater volume on the rate of removal of total suspended solids, turbidity, chemical oxygen demand, and the content of total and ammonium nitrogen were analyzed, taking into account the values of these parameters measured at the end of each operating cycle. In addition to the impacts on the aforementioned physicochemical indices, the influence of drilling fluid on the biomass of various groups of eukaryotes in activated sludge was analyzed. The impact of the drilling fluid was highly dependent on its type and dosage. A noticeable slowdown in the rate of the wastewater treatment process and a negative effect on the organisms were observed after the addition of DF2. This effect intensified after an increase in fluid dose. However, no statistically significant negative changes were observed after the introduction of DF1. Conversely, the removal rate of some of the analyzed pollutant increased.

Evaluation of the efficiency of the mixing system of the laboratory SBR-type reactor

“…One variant of wastewater treatment technology in which activated sludge has been adopted and used is the sequencing batch reactor [21,22]. In these bioreactors, during wastewater treatment, the processes occur sequentially in a single vessel and consist of consecutive cycles, usually lasting from few hours to several hours.…”

Modeling of the Aeration System of a Sequencing Batch Reactor

“…Computer modeling can be used in the design of the aeration systems utilized in activated sludge bioreactors [Vanhooren, et al 2003, Pittoors et al, 2014, Sytek-Szmeichel et al, 2016, Hreiz et al, 2019. A biological reactor working in a batch system (SBR -sequencing batch reactor) is one of the ways to use the activated sludge technology [Singh et al, 2011, Babko et al, 2017. The processes occurring during the wastewater treatment take place sequentially in one tank and consist of several successive cycles usually lasting from several to more than ten hours.…”