# Does Continuous Bioaugmentation of Aerated Stabilization Basins Improve Performance? A Field Scale Trial With a Control

## TL;DR

A field study found that adding microbes to wastewater treatment basins did not improve performance or change microbial communities.

## Contribution

This is one of the few full-scale controlled studies on bioaugmentation in pulp and paper wastewater treatment.

## Key findings

- Bioaugmentation did not significantly improve BOD or TSS levels in wastewater treatment basins.
- Microbial community analysis showed no significant change due to bioaugmentation.
- Filamentous bacterial blooms, not bioaugmentation, likely caused observed differences in TSS and BOD.

## Abstract

Continuous bioaugmentation is widely employed across the pulp and paper industry in attempts to improve the resilience of wastewater treatment systems or the performance of undersized (in terms of volume, aeration, or nutrient supply) systems. Bench and field scale research into bioaugmentation has shown that success is often unpredictable. A field scale trial at an aerated lagoon system treating pulp and paper mill wastewater was completed over a 6‐month period. The system consisted of two nearly identical trains of aerated stabilization basins (ASBs), one operated as a control and the other treated with a commercially available bioaugmentation product. The control and treated basins were then switched to minimize train‐specific effects. Throughout the trial, changes in soluble or total biochemical oxygen demand (sBOD5 and TBOD5, respectively) or total suspended solids (TSS) at the first of the two ponds in series were not associated with bioaugmentation. In the second set of ponds, bioaugmentation was associated with 6.0 ± 2.6 mg/L higher TBOD5 and 12.4 ± 5.2 mg/L higher TSS. Further, 16S rRNA gene sequencing identified high levels of Thiothrix in the bioaugmented train, whereas TSS data between the trains diverged. This provided evidence that the significant difference in BOD and TSS was likely due to a microbial community dominated by a filamentous bacterial bloom rather than bioaugmentation.

Bioaugmentation studies, with controls, at full scale wastewater systems are rare.Full‐scale tests with control reactors at a pulp and paper facility were performed.Comprehensive physical, chemical, and microbial parameters were measured.No significant improvement in general performance observed due to bioaugmentation.Bioaugmentation was not associated with a change in the microbial community.

Bioaugmentation studies, with controls, at full scale wastewater systems are rare.

Full‐scale tests with control reactors at a pulp and paper facility were performed.

Comprehensive physical, chemical, and microbial parameters were measured.

No significant improvement in general performance observed due to bioaugmentation.

Bioaugmentation was not associated with a change in the microbial community.

Full‐scale bioaugmentation tests, with controls, in aerated stabilization basins treating pulp and paper mill wastewater were performed. The results from physical, chemical, and DNA sequencing analyses showed that bioaugmentation was not associated with a significant change in microbial communities nor significant improvement in general performance.