Variations in fluid chemistry and membrane phospholipid fatty acid composition of the bacterial community in a cold storage groundwater system during clogging events
Highlights
► First biogeochemical monitoring of a geothermally used aquifer (cold storage). ► Indication of biological mediated clogging events by microbial biomarkers. ► Application of novel PLFA ratios to evaluate the contribution of microbes in clogging events. ► Fluid constituents as potential electron donor and acceptors for microbial life.
Introduction
In recent years, Aquifer Thermal Energy Storage (ATES) systems have become increasingly important for cooling and heating of buildings by storing natural cold or surplus heat in subsurface formations. For a reliable operation of an ATES, it is important to understand the impact of the geothermal plant on the groundwater system. Problems in the technical plant can occur in terms of corrosion, scaling, and clogging all reducing the geothermal utilizability of the aquifer and the operational reliability of the geothermal plant.
Clogging processes can be classified into three categories: physical, chemical and biological (Baveye et al., 1998). The physical clogging progression is mainly caused by suspended solids leading to the accumulation of the suspended solids in the downhole plant tubes and the formation of a filter cake as well as the blocking of pore spaces in the aquifer (Baveye et al., 1998).
The chemical clogging process is linked to chemical parameters in the respective aquifers such as electrolyte concentration, fraction of organic compounds in the aqueous phase, pH, Eh as well as the mineralogical composition of the solid phase, its surface characteristics, and the chemical reactions (precipitation/dissolution) which can lead to clay-sized particles lodging in the pores (Baveye et al., 1998). Chemical plugging is related to scaling formed by precipitation of e.g. gypsum, carbonates or hydroxides (van Beek, 1989). Worldwide, the most often occurring chemical clogging events in water supply systems are induced by the precipitation and deposition of Fe-oxyhydroxides (van Beek, 1989). Abiotic Fe precipitation in wells can be caused by the contact of anoxic groundwater with atmospheric O2 as e.g. realized by changing water tables (Van Beek et al., 2009) or by mixing with O2-containing groundwater.
The biologically mediated clogging is caused by the activity of microorganisms in the aquifer or plant (Ralph and Stevenson, 1995, Potekhina et al., 1999, Rinck-Pfeiffer et al., 2000, Inagaki et al., 2003, Coetser and Cloete, 2005). The clogging material is often found to be slimy layers (Smith and Tuovinen, 1985). These biofilms consisting of bacterial populations surrounded by a thick film of microbially derived extracellular polymeric substances EPS are located at or outside the cell surface (Costerton et al., 1995, Laspidou and Rittmann, 2002). They are highly hydrated and form a matrix keeping the cells together and retaining water (Flemming et al., 2007). The biofilm EPS are composed of polysaccharides, proteins, and nucleic acids as well as microbially produced organic substances or the residue of dead cells (Stoodley et al., 2002). The EPS can trap, bind and accumulate organic material as well as capture suspended solids and inorganic precipitates (Laspidou and Rittmann, 2002, Stoodley et al., 2002). Søgaard et al. (2001) showed that rates of biotic Fe oxidation can be 1000 times faster than for abiotic Fe oxidation and the involved biofilm and its EPS serve as a catalyst for the oxidation/precipitation process as well as preventing re-dissolution of the Fe(III) precipitates (Søgaard et al., 2000).
Furthermore biofouling and biocorrosion of construction materials within the plant caused by microbial biofilms can lead to problems in industrial process water and potable water (Sand, 2003, Ungemach, 2003, Coetser and Cloete, 2005). These phenomena can also cause severe disturbances in the technical equipment of geothermal plants such as pipes, pumps, screens, and heat exchangers leading to substantial operating expense. Additionally, the lifetime of geothermal systems is often limited not only by the wearout of the technical equipment but also by the formation and deposition of scale in the well and in the vicinity of the wells (clogging) (van Beek and van der Kooij, 1982, van Beek, 1989, Ralph and Stevenson, 1995).
Sometimes chemical, physical or biological clogging processes can also occur simultaneously. In these cases their interaction makes it difficult to determine which process has been the initial mechanism and which is the most prevalent.
To date, little is known about the biogeochemical interactions of microorganisms within a geothermal plant and the impact of seasonal changes during different operating modes of the plant on the indigenous microbial community. In the current study, biogeochemical monitoring of the fluid chemistry and bacterial community was conducted for the cold storage of the German Parliament buildings (Reichstag ATES) in Berlin from August 2006 to August 2009. During this time, two periods of reduced injection were observed in the plant. The aim of the study was to investigate the changes in the fluid chemistry and bacterial community with time, especially, related to these events. While microbiological approaches were covered by partners in the project (Lerm et al., 2011), the current biogeochemical approach aims to monitor changes in the bacterial communities using characteristic microbial lipid markers such as phospholipids. These biomarkers, forming a major part of the bacterial cell membranes, are regarded to be indicators for living bacterial communities due to their rapid degradation after cell death (White et al., 1979, Harvey et al., 1986). An advantage of this method is that the phospholipid signal represents the whole indigenous bacterial community and, therefore, covers the compositional changes of the whole bacterial population during the monitoring. For the fluid analysis the focus was placed on selected fluid components being potential electron acceptors () and donors (dissolved organic C, DOC) for the indigenous microbial community in the ATES.
Section snippets
Study site and operating modes of the Reichstag ATES
The energy supply system of the German Parliament buildings in Berlin, one of the first ATES projects in Germany (Poppei et al., 1998), exhibits two independent energy storage systems supplying cold and heat to the Reichstag building and surrounding offices (Kabus and Seibt, 2000, Sanner, 2001). Both storage systems were established in 1999. In the current study only the seasonal cold storage was investigated.
The freshwater aquifer that is used for the cold storage of the German Parliament
Clogging events in the cold storage
During discharge mode in summer 2006 (August–October) and 2008 (July to October) an increased injection pressure occurred on the warm side caused by clogging events. The first clogging event (summer 2006) is not well documented. The well slides were covered with Fe hydroxide crusts. Regeneration of the wells on the warm side was conducted in May and June 2007. A further decrease in the injection rate occurred in July 2008. Until October the decrease in the injection rate developed to be a
Fluid and filter sampling
Between May 2007 and April 2009 the fluid chemistry in the storage system of the ATES system was monitored. All samples were taken from the Paul-Löbe-House (Fig. 1). Initially, fluid samples were only occasionally taken during charge and discharge operating modes between May 2007 and March 2008. Since May 2008 fluid samples have been sampled monthly during the different operating modes. In total 15 fluid samples were taken all from the tapping point prior to the filter unit (tapping point A in
Potential carbon and energy sources for the microbial community in the fluids from the ATES system
Groundwater samples from the individual wells of the cold and warm side (Table 1) showed variations in anion concentrations. Sulfate content from the warm wells (on average 205 mg/L) was lower compared to the content of the cold side (on average 249 mg/L) and low molecular weight organics such as formate and acetate only showed a peak in the IC chromatograms on the cold side. However, the signal was too small for quantification (<0.5 mg/L). These results could be an indication of a higher
Conclusions
Biogeochemical monitoring was conducted for the cold storage of the German Parliament buildings in Berlin over three years. This monitoring comprised the characterization of the fluid chemistry in the process water and the indigenous microbial community by phospholipid fatty acid analysis of filter material. During the monitoring, two periods of reduced injection occurred in 2006 and 2008 due to clogging events. These clogging periods were characterized by increased Fe hydroxide formation and,
Acknowledgements
We would like to thank the persons in charge of the ATES of the German Parliament buildings for granting us permission to monitor the ATES and to publish our results. In addition, we gratefully acknowledge Oliver Opel (Leuphana University of Lüneburg), Andrea Seibt (BWG, Neubrandenburg), and Stefan Kranz (GFZ Potsdam) for providing unpublished data from the Reichstag ATES. We are grateful to Kristin Günther, Bastian Kasek, Cornelia Karger, Anke Kaminsky and Ursula Kegel for their technical and
References (87)
- et al.
Bacterial communities in peat in relation to botanical composition as revealed by phospholipid fatty acid analysis
Soil Biol. Biochem.
(1994) - et al.
Effect of selected environmental and physico-chemical factors on bacterial cytoplasmic membranes
J. Microbiol. Methods
(2003) - et al.
Phospholipid fatty acid and infra-red spectroscopic analysis of a sulphate-reducing consortium
FEMS Microbiol. Lett.
(1988) - et al.
Biomarker analysis of microbial diversity in sediments of a saline groundwater seep of Salt Basin, Nebraska
Organic Geochemistry
(2006) - et al.
Phospholipid, ester-linked fatty acid profiles as reproducible assay for changes in prokaryotic community structure of estuarine sediments
Microb. Ecol.
(1985) - et al.
The effect of organic matter and oxygen on the degradation of bacterial membrane lipids in marine sediments
Geochim. Cosmochim. Acta
(1986) - et al.
The cis/trans isomerisation of unsaturated fatty acids in Pseudomonas putida S12: An indicator for environmental stress due to organic compounds
Chemosphere
(1995) - et al.
The cis–trans isomerase of unsaturated fatty acids in Pseudomonas and Vibrio: biochemistry, molecular biology and physiological function of a unique stress adaptive mechanism
FEMS Microbiol. Lett.
(2003) - et al.
Characterisation of aquatic humic and non-humic matter with size-exclusion chromatography–organic carbon detection–organic nitrogen detection (LC–OCD–OND)
Water Res.
(2011) - et al.
Comparison of phylogenetic relationships based on phospholipid fatty acid profiles and ribosomal RNA sequence similarities among dissimilatory sulfate-reducing bacteria
FEMS Microbiol. Lett.
(1994)
A unified theory for extracellular polymeric substances, soluble microbial products, and active and inert biomass
Water Res.
The role of bacteria in well clogging
Water Res.
Interrelationships between biological, chemical, and physical processes as an analog to clogging in aquifer storage and recovery (ASR) wells
Water Res.
Volatile organic acids and microbial processes in the Yegua formation, east-central Texas
Appl. Geochem.
Phospholipid analysis as a tool to study complex microbial communities in marine sediments
J. Microbiol. Methods
Classification of dissolved organic carbon (DOC) in river systems: influence of catchment characteristics and autochthonous processes
Org. Geochem.
Microbial life in geothermal waters
Geothermics
Conditions and rates of biotic and abiotic iron precipitation in selected Danish freshwater plants and microscopic analysis of precipitate morphology
Water Res.
Conditions for biological precipitation of iron by Gallionella ferruginea in a slightly polluted ground water
Appl. Geochem.
Biosynthesis of phosphatidylcholine in bacteria
Prog. Lipid Res.
Reinjection of cooled geothermal brines into sandstone reservoirs
Geothermics
Water extraction of coals – potential for estimating low molecular weight organic acids as carbon feedstock for the deep terrestrial biosphere
Org. Geochem.
Acetate bioavailability and turnover in an estuarine sediment
FEMS Microbiol. Ecol.
Intact phospholipids – microbial “life markers” in marine deep subsurface sediments
Org. Geochem.
Environmental impact and mechanisms of the biological clogging of saturated soils and aquifer materials
Crit. Rev. Environ. Sci. Technol.
A rapid method of total lipid extraction and purification
Can. J. Biochem. Physiol.
Significance and taxonomic value of iso and anteiso monoenoic fatty acids and branded beta-hydroxy acids in Desulfovibrio desulfuricans
J. Bacteriol.
Biofouling of groundwater systems by Thiothrix spp
Curr. Microbiol.
Molecular weight, polydispersity, and spectroscopic properties of aquatic humic substances
Environ. Sci. Technol.
Biofouling and biocorrosion in industrial water systems
Crit. Rev. Microbiol.
Microbial Biofilms
Annu. Rev. Microbiol.
Impacts of environmental changes on the biogeochemistry of aquatic humic substances
Hydrobiologia
FISH shows that Desulfotomaculum spp. are the dominating sulfate-reducing bacteria in a pristine aquifer
Microb. Ecol.
The conversion of cis into trans unsaturated fatty acids in Pseudomonas putita P8: evidence for a role in the regulation of membrane fluidity
Appl. Microbiol. Biotechnol.
Molecular basis for membrane phospholipid diversity: why are there so many lipids?
Annu. Rev. Biochem.
The EPS matrix: the “house of biofilm cells”
J. Bacteriol.
Trans-monounsaturated acids in a marine bacterial isolate
Appl. Environ. Microbiol.
Analysis of phospholipid fatty acids (PLFA) to characterize microbial communities in aquifers
Hydrogeol. J.
Phospholipid ester-linked fatty acid profile changes during nutrient deprivation of Vibrio cholerae: increases in the trans/cis ratio and proportions of cyclopropyl fatty acids
Appl. Environ. Microbiol.
Benefits associated with the stalk of Gallionella ferruginea, evaluated by comparison of a stalk-forming and a non-stalk-forming strain and biofilm studies in situ
Microb. Ecol.
Disturbance, starvation, and overfeeding stresses detected by microbial lipid biomarkers in high-solids high-yield methanogenic reactors
J. Ind. Microbiol.
Spectral characterisation of eight glycerolipids and their detection in natural samples using time-of-flight secondary ion mass spectrometry
Rapid Commun. Mass Spectrom.
Conversion of cis unsaturated fatty acids to trans, a possible mechanism for the protection of phenol-degrading Pseudomonas putida P8 from substrate toxicity
Appl. Environ. Microbiol.
Cited by (15)
Variations in bacterial community during bioclogging in Managed Aquifer Recharge (MAR): A laboratory study
2020, International Biodeterioration and BiodegradationCombination of aquifer thermal energy storage and enhanced bioremediation: Biological and chemical clogging
2018, Science of the Total EnvironmentCitation Excerpt :Accepting that the benefits anticipated for the combination concept of ATES and enhanced bioremediation outweigh the risk of contaminant spreading, a remaining issue of concern is potential biological clogging of ATES wells due to the enhanced growth of microorganisms (Brons, 1992; Soleimani et al., 2009). Being a common phenomenon in many groundwater systems (De Zwart, 2007), clogging is also the most concerning problem during the operation of ATES (Vetter et al., 2012; Hartwig, 2013) as it will cause an increase in pressure and resistance in the injection well (Rinck-Pfeiffer et al., 2000). Under normal conditions, without biostimulation, chemical clogging is a well know phenomenon for ATES, especially the precipitation of Fe and Mn oxide or hydroxide.
Monitoring of microbially mediated corrosion and scaling processes using redox potential measurements
2014, BioelectrochemistryCitation Excerpt :However, microbial processes can alter corrosion and scaling kinetics largely. Microbially induced corrosion (MIC) as well as microbially mediated clogging and scaling can occur both in hydraulic and potable water systems and in reduced natural geothermal waters [1,6–14]. Sulphide and sulphur species, that are often produced by sulphate reducing bacteria (SRB) in these systems, are known to be a strong contributor to microbial corrosion (MIC) processes [8,15,16,9].
Fluid chemistry and impact of different operating modes on microbial community at Neubrandenburg heat storage (Northeast German Basin)
2012, Organic GeochemistryCitation Excerpt :The operation of such plants can be influenced by abiotic and biotic processes, leading to massive plant disturbance by way of clogging events caused by e.g. iron hydroxide precipitation and biofilms. Microbiological and biogeochemical studies have shown that geothermally used aquifers form an appropriate life habitat for microbial communities (Brielmann et al., 2009; Lerm et al., 2011a; Vetter et al., 2011, 2012). Due to their ability to form biofilms, microbial populations can have a strong impact on the working reliability of the plants (Lerm et al., 2011b; Vetter et al., 2012).