Characteristics of organic carbon metabolism and bioremediation of petroleum-contaminated soil by a mesophilic aerobic biopile system. (February 2021)

• Record Type: Journal Article
• Authors: Zhang, Kai; Wang, Sa; Guo, Penghong; Guo, Shuhai
• Is Part Of: Chemosphere. Volume 264(2021)Part 2
• Publication Date: 2021-02
• Subjects: Mesophilic conditions -- Aeration rate -- Bioavailable organic carbon -- Petroleum degradation -- Microbial community; Pollution -- Periodicals; Pollution -- Physiological effect -- Periodicals; Environmental sciences -- Periodicals; Atmospheric chemistry -- Periodicals; 551.511
• DOI: 10.1016/j.chemosphere.2020.128521
• Languages: English
• ISSNs: 0045-6535

Abstract

Abstract: An innovative mesophilic aerobic biopile technology was explored to improve the bioremediation efficiency of petroleum-contaminated soil. Under the suitable soil conditions (C:N:P at 100:5:1 and soil moisture content at 18%), the soil pH was hold in the range of 7.4 to 6.8 throughout the bioremediation process, the mesophilic (30 °C-40 °C) and forced aeration (3 h-on/1 h-off) conditions were the critical factors to enhancing petroleum biodegradation. The consumption of bioavailable organic carbon (BAC) which was one of the most important factors regulating microbial metabolism, was positively related ( R 2 = 0.85, 40 °C) with the rate of petroleum removal. The 50% threshold of BAC could be regarded as the signal for supplementing the soil nutrients in the mesophilic aerobic biopiles to favor petroleum removal. The optimal conditions (40 °C, 3 h-on/1 h-off) maximized the utilization of BAC, promoted the petroleum degradation, and remained the microbial abundance and community composition stable to the greatest extent. In addition, the accumulation of aliphatic acids affected the microbial activity, which limited the efficiency of petroleum degradation to a certain extent. Jointly considering the energy consumption, time cost and soil conditions maintenance, a cost-effective biopile technology was obtained by temperature and aeration regulation and BAC supplementation, which could be applied to engineering application. Highlights: Mesophilic and low aeration rate conditions effectively improved biopile systems. Bioavailable organic carbon (BAC) was the core factor to characterize bioremediation processes in the biopiles. BAC consumption positively correlated with petroleum biodegradation. Microbial abundance and community composition changed dynamically in the biopiles. Microbial functions were affected by the BAC, temperature, aeration and metabolites.