Evaluating the low-rank coal degradation efficiency bioaugmented with activated sludge

Scientific Reports, vol. 14, pp. 14827

Abstract

Microbial bioaugmentation of coal is considered as a viable and ecologically sustainable approach for the utilization of low-rank coals (LRC). The search for novel techniques to derive high-value products from LRC is currently of great importance. In response to this demand, endeavors have been undertaken to develop microbially based coal solubilization and degradation techniques. The impact of supplementing activated sludge (AS) as a microbial augmentation to enhance LRC biodegradation was investigated in this study. The LRC and their biodegradation products were characterized using the following methods: excitation-emission Matrices detected fluorophores at specific wavelength positions (O, E, and K peaks), revealing the presence of organic complexes with humic properties. FTIR indicated the increased amount of carboxyl groups in the bioaugmented coals, likely due to aerobic oxidation of peripheral non-aromatic structural components of coal. The bacterial communities of LRC samples are primarily composed of Actinobacteria (up to 36.2%) and Proteobacteria (up to 25.8%), whereas the Firmicutes (63.04%) was the most abundant phylum for AS. The community-level physiological profile analysis showed that the microbial community AS had high metabolic activity of compared to those of coal. Overall, the results demonstrated successful stimulation of LRC transformation through supplementation of exogenous microflora in the form of AS.

Authors 4

1. Marzhan Kozhakhmetova corresponding

   Al-Farabi Kazakh National University

   Affiliation as printed

   Al-Farabi Kazakh National University, 050040, Almaty, Kazakhstan. marzhanur.7@mail.ru

   Al-Farabi Kazakh National University, 050040, Almaty, Kazakhstan

2. Nuraly Sh. Akimbekov

   Al-Farabi Kazakh National University · Ahmet Yesevi University · West Kazakhstan Marat Ospanov State Medical University

   Affiliation as printed

   Al-Farabi Kazakh National University, 050040, Almaty, Kazakhstan

   Khoja Akhmet Yassawi International Kazakh-Turkish University, 161200, Turkestan, Kazakhstan

   West Kazakhstan Marat Ospanov Medical University, Maresyev Str. 68, 030019, Aktobe, Kazakhstan

3. Ilya Digel Aachen

   FH Aachen

   Affiliation as printed

   Aachen University of Applied Sciences, Heinrich-Mussmann-Straße 1, 52428, Jülich, Germany

4. Kuanysh T. Tastambek

   Al-Farabi Kazakh National University · Ahmet Yesevi University · M.Auezov South Kazakhstan State University

   Affiliation as printed

   Al-Farabi Kazakh National University, 050040, Almaty, Kazakhstan

   Khoja Akhmet Yassawi International Kazakh-Turkish University, 161200, Turkestan, Kazakhstan

   M. Auezov South Kazakhstan University, 160012, Shymkent, Kazakhstan