Available at www.sciencedirect.com journal homepage: www.elsevier.com/locate/watres Review Chemical and biological technologies for hydrogen sulfide emission control in sewer systems: A review Lehua Zhang, Peter De Schryver, Bart De Gusseme, Willem De Muynck, Nico Boon, Willy Verstraete à Laboratory of Microbial Ecology and Technology (LabMET), Ghent University, Coupure Links 653, B-9000 Ghent, Belgium article info Article history: Received 19 March 2007 Received in revised form 10 July 2007 Accepted 12 July 2007 Available online 19 July 2007 Keywords: Concrete corrosion Thiobacillus Sulfate attack Sewage Iron salts Nitrate Microbial fuel cells abstract Biogenic corrosion of sewers represents a cost of about 10% of total sewage treatment cost in Flanders (Belgium) and is further increasing. In the past, research has resulted in a number of prevention methods, such as injection of air, oxygen, H 2 O 2 , NaClO, FeCl 3 and FeSO 4 . The possibility of biological oxidation of sulfide using nitrate as the electron acceptor has also been explored in sewer systems. However, all of these methods have a problem with the high cost (h1.9–7.2 kg 1 S removal). In this review, new approaches for hydrogen sulfide emission control in sewer systems are discussed. The control of hydrogen sulfide emission by using a microbial fuel cell (MFC) can be cost-effective while the BOD is removed partially. The use of phages that target sulfate-reducing bacteria (SRB) can possibly inhibit sulfide formation. Novel inhibitors, such as slow release solid-phase oxygen (MgO 2 /CaO 2 ) and formaldehyde, warrant further study to control hydrogen sulfide emission in sewer systems. & 2007 Elsevier Ltd. All rights reserved. Contents 1. Introduction .................................................................................... 2 2. Biogenic corrosion of sewer systems ................................................................. 2 2.1. Sulfur cycle in sewers and the environmental parameters ............................................ 2 2.2. Sewer corrosion by hydrogen sulfide emission ..................................................... 4 3. Increasing redox potential to control sulfide formation ................................................... 4 3.1. Air or oxygen injection ........................................................................ 4 3.2. Addition of nitrate ........................................................................... 5 4. Inhibition of SRB activity .......................................................................... 5 5. Chemical removal of sulfide ........................................................................ 5 5.1. Precipitation by metal salts .................................................................... 5 5.1.1. Insoluble metal sulfides in sewage ........................................................ 5 5.1.2. Addition of iron salts ................................................................... 5 ARTICLE IN PRESS 0043-1354/$ - see front matter & 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.watres.2007.07.013 à Corresponding author. Tel.: +32 9 264 59 76; fax: +32 9 264 62 48. E-mail address: Willy.Verstraete@UGent.be (W. Verstraete). WATER RESEARCH 42 (2008) 1– 12