Identification of Microbiological Activities in Wet Flue Gas Desulfurization Systems

Abstract

Thermoelectric power generation from coal requires large amounts of water, much of which is used for wet flue gas desulfurization (wFGD) systems that minimize sulfur emissions, and consequently, acid rain. The microbial communities in wFGDs and throughout thermoelectric power plants can influence system performance, waste processing, and the long term stewardship of residual wastes. Any microorganisms that survive in wFGD slurries must tolerate high total dissolved solids concentrations (TDS) and temperatures (50–60°C), but the inocula for wFGDs are typically from fresh surface waters (e.g., lakes or rivers) of low TDS and temperatures, and whose activity might be limited under the physicochemically extreme conditions of the wFGD. To determine the extents of microbiological activities in wFGDs, we examined the microbial activities and communities associated with three wFGDs. O2 consumption rates of three wFGD slurries were optimal at 55°C, and living cells could be detected microscopically, indicating that living and active communities of organisms were present in the wFGD and could metabolize at the high temperature of the wFGD. A 16S rRNA gene-based survey revealed that the wFGD-associated microbial communities included taxa attributable to both thermophilic and mesophilic lineages. Metatranscriptomic analysis of one of the wFGDs indicated an abundance of active Burholderiaceae and several Gammaproteobacteria, and production of transcripts associated with carbohydrate metabolism, osmotic stress response, as well as phage, prophages, and transposable elements. These results illustrate that microbial activities can be sustained in physicochemically extreme wFGDs, and these activities may influence the performance and environmental impacts of thermoelectric power plants.

Chemical and Process Engineering

“…There was no significant change of Hg(0) capture rate within one hour experiment when the simulated gas contained 1000 ppm of SO 2 (Deng and Macherzynski, 2022;Gorecki et al, 2022). The sulfate-reducing bacteria (SRB) were found in the WFGD systems (Brown et al, 2012;Martin et al, 2021).…”

Occurrence Characteristics of Fine-Grained Pyrite in Coal and Its Scaling Effect on Flotation Desulfurization

“…Sulfur is one of the main harmful elements in coal, which affects the quality of industrial products, corrodes equipment, and endangers human health and ecological environment during coal combustion. , Sulfur in coal is mainly controlled by the sedimentary environment of coal, especially by the seawater factor . The formation environment of coal seams in China includes offshore and continental deposits, and the content and distribution of sulfur in coal vary in different regions.…”