Black-odor water body remediations by ecological floating island coupled with Ecobase and Acinetobacter haemolyticus: Lab and pilot tests

Abstract

Background

Energy-efficient remediation technology for black and odorous water bodies in cold and salty areas is in high demand. This study experimentally investigated the performance of a novel integrated process at lab and pilot scales, in both batch and continuous-flow modes, to treat black and odorous lake water from Daqing City, China.

Methods

In 25-liter batch tests, relevant influence conditions were optimized. The 756-liter batch tests confirmed these results. Meanwhile, a continuous flow experiment was added to improve the removal rate of pollutants further.

Significant findings

In 25-liter batch tests maximum removal rates for COD, NH₄⁺-N, TP, and TN were 78.6 %, 72.3 %, 79.1 %, and 76.3 %, respectively, using reed plants and carbon fiber grass with L₂ bacteria under optimal conditions (two cfb per floating-island unit, pH 8, DO of 4 mg/L, 25–30 °C, microbial enhancer of 0.75 g/flu). The 756-liter batch tests confirmed these results, achieving improved removal rates of 80.4 %, 75.1 %, 75.5 %, and 78.4 % over 30 days. Continuous-flow tests yielded maximum removal rates of 85.2 %, 89.5 %, 87.4 %, and 90.1 % at an 8-hour HRT, demonstrating superior performance under short retention times. The study revealed interactions with the key biological processes during remediation. The proposed costs for this method indicate high feasibility for field applications.