title: Revealing biogenic sulfuric acid corrosion in sludge digesters: detection of sulfur-oxidizing bacteria within full-scale digesters.
abstract: Biogenic sulfuric acid corrosion (BSA) is a costly problem affecting both sewerage infrastructure and sludge handling facilities such as digesters. The aim of this study was to verify BSA in full-scale digesters by identifying the microorganisms involved in the concrete corrosion process, that is, sulfate-reducing (SRB) and sulfur-oxidizing bacteria (SOB). To investigate the SRB and SOB communities, digester sludge and biofilm samples were collected. SRB diversity within digester sludge was studied by applying polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) targeting the dsrB-gene (dissimilatory sulfite reductase beta subunit). To reveal SOB diversity, cultivation dependent and independent techniques were applied. The SRB diversity studies revealed different uncultured SRB, confirming SRB activity and H2S production. Comparable DGGE profiles were obtained from the different sludges, demonstrating the presence of similar SRB species. By cultivation, three pure SOB strains from the digester headspace were obtained including Acidithiobacillus thiooxidans, Thiomonas intermedia and Thiomonas perometabolis. These organisms were also detected with PCR-DGGE in addition to two new SOB: Thiobacillus thioparus and Paracoccus solventivorans. The SRB and SOB responsible for BSA were identified within five different digesters, demonstrating that BSA is a problem occurring not only in sewer systems but also in sludge digesters. In addition, the presence of different SOB species was successfully associated with the progression of microbial corrosion.
authors.affiliation: Chair of Urban Water Systems Engineering, Technische Universität München, Am Coulombwall 8, 85748 Garching, Germany E-mail: bettina.huber@tum.de.
authors.forename: B
authors.initials: B
authors.lastname: Huber
authors.affiliation: Chair of Urban Water Systems Engineering, Technische Universität München, Am Coulombwall 8, 85748 Garching, Germany E-mail: bettina.huber@tum.de.
authors.forename: J E
authors.initials: JE
authors.lastname: Drewes
authors.affiliation: Chair of Urban Water Systems Engineering, Technische Universität München, Am Coulombwall 8, 85748 Garching, Germany E-mail: bettina.huber@tum.de.
authors.forename: K C
authors.initials: KC
authors.lastname: Lin
authors.affiliation: Weber-Ingenieure GmbH, Bauschlotter Straße 62, 75177 Pforzheim, Germany.
authors.forename: R
authors.initials: R
authors.lastname: König
authors.affiliation: Chair of Urban Water Systems Engineering, Technische Universität München, Am Coulombwall 8, 85748 Garching, Germany E-mail: bettina.huber@tum.de.
authors.forename: E
authors.initials: E
authors.lastname: Müller
mesh_terms: D013856:Acidithiobacillus thiooxidans / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D020562:Betaproteobacteria / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D019149:Bioreactors; D003343:Corrosion; D058645:Denaturing Gradient Gel Electrophoresis; D005798:Genes, Bacterial; D050885:Hydrogensulfite Reductase / Q000235:genetics; D010084:Oxidation-Reduction; D010230:Paracoccus / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D016133:Polymerase Chain Reaction / Q000379:methods; D012722:Sewage / Q000382:microbiology; D013431:Sulfates / Q000378:metabolism; D013455:Sulfur / Q000378:metabolism; D013464:Sulfuric Acids / Q000737:chemistry* / Q000378:metabolism; D014865:Waste Disposal, Fluid
chemical_list: D012722:Sewage; D013431:Sulfates; D013464:Sulfuric Acids; D013455:Sulfur; D050885:Hydrogensulfite Reductase; C033158:sulfuric acid