Biogas production from the sludge of the municipal wastewater treatment plant of Adrar city (southwest of Algeria) S. Kalloum a, *, H. Bouabdessalem b , A. Touzi a , A. Iddou c,d , M.S. Ouali d a Unit of Research in Renewable Energies in Saharan Medium, Adrar, Algeria b Normal Higher School of Technical Teaching, Oran, Algeria c University of Sciences and Technology-Mohammed Boudiaf Oran, BO 1505 EL M’naouar, 31000, Oran, Algeria d Laboratory of materials valorization and nuisances treatment, Ibn badis University of Mostaganem, BO 227, Mostaganem 27000, Algeria article info Article history: Received 14 September 2009 Received in revised form 10 January 2011 Accepted 10 February 2011 Available online 5 April 2011 Keywords: Sludge Municipal wastewater treatment plant Organic matter Digestion Biogas Energy abstract This study deals with the treatment and valorization of sludge issued from the municipal wastewater treatment plant of Adrar city (southwest of Algeria). The sludge considered was a complex mixture of substances, essentially organic matters with a rate of 54%. An acute biological activity of the crude substrate was noted (1.67 10 6 germs/1 ml). The diluted sludge with a content of 16 g/l of total solids (TS) was fermented in a digester of one litter capacity under anaerobic conditions during 33 days. The quantity of biogas produced was 280.31 Nml with a yield of 30 Nml of biogas/mg of COD removed. The COD, BOD and TS reduction yields were 88, 90 and 81% respectively, followed by a complete destruction of the pathogenic flora particularly Escherichia coli. This study presented an important ener- getic opportunity by producing 30,950 KWh. ª 2011 Published by Elsevier Ltd. 1. Introduction The urban wastewater treatment plant has a role to eliminate the pollution contained in the domestic and industrials effluents before their rejection in the natural environment. If water, at the end of the treatment, was purified, initial pollution was found stored and concentrated in sludge resulting from the various water treatment stages. This sludge can be considered like a recyclable waste and must be elimi- nated in laws respect. Sludge management, valorization and elimination, were problematic as well as the other waste (OMS) [1]. Several paths exist for sludge treatment and valo- rization, but the choice must be tributary of the installation cost, sludge origin, the added value of the product which results from it and of the environment impact that could have the retained path. The landfill proves to be a technique little developing and legally prohibited in our country. Sludge incineration has a prohibitory cost and presents a risk related to the impact of pollutant gases emission on the environment such as the dioxane (ADEME) [2]. The biologic or agricultural valorization (production of manure and compost) constituted a green * Corresponding author. E-mail addresses: kadertouzi@yahoo.fr (S. Kalloum), icenvironnement@hotmail.com (H. Bouabdessalem), iddouabdelkader@yahoo.fr (A. Iddou). Available at www.sciencedirect.com http://www.elsevier.com/locate/biombioe biomass and bioenergy 35 (2011) 2554 e2560 0961-9534/$ e see front matter ª 2011 Published by Elsevier Ltd. doi:10.1016/j.biombioe.2011.02.012