The main objective of this work was to study the feasibility of biohydrogen production by heat-treated anaerobic sludge with glucose as carbon substrate and ammonium as nitrogen source, obtained from the electrochemical reduction of concentrated nitrate solutions (3 g L-1 NO3-), namely model solutions simulating those obtained after physicochemical denitrification of industrial wastewaters. Experiments were realized in bacth systems involving 125 mL (without pH control) and 3 L (with pH control) reactor, respectively. In order to find the optimal conditions for H-2 production, the first set of experiments were conducted without pH control at various initial pH (pH 5.5, 6.5 and 7.5) and glucose concentrations (5-30 g L-1); and the highest H-2 yield (1.1 mol H-2 Mol(-1) (glucose consumed)) was reached for a glucose concentration of 25 g L-1 and at pH 6.5. These optimal conditions were then considered to examine the effect of pH control on biohydrogen production, in a 3 L bioreactor. The pH control allowed a considerable improvement of the hydrogen gas conversion efficiency, which reached 2.02 mol H-2 Mol(-1) (glucose consumed). Copyright (C) 2016, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.