Optimizing nutrient removal and biomass production of the Algal Turf Scrubber (ATS) under variable cultivation conditions by using Response Surface Methodology

Xinyu Gan; Holger Klose; Diana Reinecke

doi:10.3389/fbioe.2022.962719

Optimizing nutrient removal and biomass production of the Algal Turf Scrubber (ATS) under variable cultivation conditions by using Response Surface Methodology

Front Bioeng Biotechnol. 2022 Sep 6:10:962719. doi: 10.3389/fbioe.2022.962719. eCollection 2022.

Authors

Xinyu Gan^{1

2}, Holger Klose^{1

3}, Diana Reinecke¹

Affiliations

¹ IBG2-Plant Sciences, Forschungszentrum Jülich GmbH, Jülich, Germany.
² Faculty of Agriculture, University of Bonn, Bonn, Germany.
³ RWTH Aachen University, Aachen, Germany.

Abstract

This study investigated and optimized the nutrient remediation efficiency of a simple low-cost algal biofilm reactor, the algal turf scrubber (ATS), for wastewater treatment. Combined effects of three cultivation variables-total inorganic carbon, nitrogen-to-phosphorous (N:P) ratio, and light intensity-were examined. The ATS nutrient removal efficiency and biomass productivity were analyzed considering the response surface methodology (RSM). The maximum removal rates of total P and N were 8.3 and 19.1 mg L^-1 d^-1, respectively. As much as 99% of total P and 100% of total N were removed within 7 days. Over the same period, the dissolved oxygen concentration and pH value of the medium increased. The optimal growth conditions for simultaneous maximum P and N removal and biomass productivity were identified. Our RSM-based optimization results provide new insights into the combined effect of nutrient and light availability on the ATS remediation efficiency and biomass productivity.

Keywords: algal biomass; algal turf scrubber; bioremediation; phosphorous removal; wastewater treatment.