Bio-Drying of Municipal Wastewater Sludge: Effects of High Temperature, Low Moisture Content and Volatile Compounds on the Microbial Community
2023
Vladimir Mironov | Ivan Moldon | Anna Shchelushkina | Vitaly Zhukov | Nataliya Zagustina
This study examined microbiological processes during the bio-drying of municipal wastewater sludge (WS) from the waste treatment facilities of the Moscow region (Russia). In just 21 days of bio-drying, the moisture content of the mixture of WS and wood chips decreased by 19.7%. It was found that members of the genus <i>Bacillus</i> were the main organic matter destructors. In the period from 7 to 14 days, the rates of organic matter mineralization and moisture loss were the highest, and bacteria of the genus <i>Bacillus</i> dominated, accounting for 43.5 to 84.6% of the bacterial community with a total number of 1.20 (±0.09) × 10<sup>6</sup> to 6.70 (±0.44) × 10<sup>5</sup> gene copies µg<sup>−1</sup>. The maximum number of <i>Amaricoccus</i> was (15.7% of the total bacterial community) in the middle of bio-drying. There was an active accumulation of nitrate nitrogen due to the oxidation of nitrogen-containing substances during the same period of time. Bacteria of the genera <i>Sphingobacterium</i>, <i>Brevundimonas</i>, <i>Brucella</i>, <i>Achromobacter</i> and fungi of the genus <i>Fusarium</i> dominated in the biofilter, which removed volatile compounds from the waste air by 90%. The obtained results allow to model the further intensification of bio-drying, as well as its efficiency and safety.
显示更多 [+] 显示较少 [-]