Evaluation of microbial agents as corrosion and scale inhibitor for industrial cooling water applications

Abstract

In this study, 6 strains of microbial agents were investigated as environment-friendly scale and corrosion inhibitors for industrial cooling water applications. The static jar tests along with characterization methods were applied to evaluate the scale inhibition performance. Results showed that under a concentration of 240 mg/L, the Nitrobacteria, Denitrobacteria and Lactobacillus agents reached high CaCO3 scale inhibition efficiencies of 83, 82, and 86% respectively. Characterization methods indicated the deposited crystals morphologies were modified and the crystals peak intensities were lowered. In addition, weight loss measurements, electrochemical measurements, surface characterization analyses were conducted to study the corrosion inhibition performances and mechanisms. It was found that at 40 °C, Bacillus cereus agent with 200 mg/L possessed the highest corrosion inhibition efficiency of 60.11% at 3 d, together with the second-lowest current density of 13.0 μA cm−2 at 12 d. The corrosion inhibition mechanisms were attributed to biofilm accumulation and biomineralization on Q235 CS surfaces to form protective film. The results suggested microbial agents have promising potential as environment-friendly scale and corrosion inhibitors for industrial cooling water applications.

The effect and mechanism of a microbial agent used for corrosion control in circulating cooling water

“…The results showed that CMP had good corrosion and scale inhibition effect, and the corrosion inhibition rate on Q235 carbon steel reached 99.69%. Hu et al 9,10 evaluated the corrosion inhibition behavior of Bacillus cereus (B. cereus) on Q235 carbon steel in simulated cooling water, whose anticorrosion efficiency was 73.88%. The results showed that the addition of B. cereus increased the charge transfer resistance of the metal and reduced the corrosion current density, allowing it to attach to the surface of Q235 carbon steel to form a tight biofilm.…”

Biofilm-induced corrosion inhibition of Q235 carbon steel by anaerobic Bacillus cereus inoculum in simulated cooling water

“…Therefore, it is necessary to dedicate the active B. cereus dry powder to industrial cooling water corrosion protection. In our previous study, B. cereus inoculum was found to possess a certain corrosion inhibition property (Hu et al, 2022b), nevertheless, detailed performances as well as some possible in uencing factors are still not explored. Under this premise, this paper investigated the corrosion behavior of Q235 CS in simulated cooling water under the presence of B. cereus inoculum.…”

Synergistic inhibition of Pseudomonas fluorescens growth and proteases activities via sodium chlorite-based oxyhalogen

“…Some strains of P. fluorescens are considered to be a high-yield protein factories, producing medicinal, food, and industrial proteins (Landry et al 2003 ; Kumar and Bhalla 2005 ; Sadeesh Kumar et al 2015 ; Morihara and Homma 2018 ; Wang et al 2022 ). P. fluorescens can be grown in bioreactors at high densities and tolerates various fermentation conditions (Schneider et al 2005 ; Hu et al 2022 ). The strong growth, heat stability, and high-level production of recombinant proteins make P. fluorescens an ideal candidate for industrial applications and cost-effective in protein recovery due to their extracellular secretions in culture medium (Landry et al 2003 ; Chew et al 2005 ; Fairbairn and Law 1986 ; Hu et al 2022 ).…”

“…P. fluorescens can be grown in bioreactors at high densities and tolerates various fermentation conditions (Schneider et al 2005 ; Hu et al 2022 ). The strong growth, heat stability, and high-level production of recombinant proteins make P. fluorescens an ideal candidate for industrial applications and cost-effective in protein recovery due to their extracellular secretions in culture medium (Landry et al 2003 ; Chew et al 2005 ; Fairbairn and Law 1986 ; Hu et al 2022 ). Another advantage is that P. fluorescens is a possible expression host for a diverse range of recombinant proteins (Chew et al 2005 ; Zhang et al 2018 ; Sindhu and Manonmani 2018 ; Park et al 2020 ; Fabia et al 2021 ).…”