A 4m(3) pilot-scale baffled continuous-flow photoreactor with four sequential chambers (#1-#4) was established and tested to evaluate its photo-fermentative hydrogen production from wastewater that contains (10 g/L glucose using a functional consortium at 30 degrees C, under light with an intensity of 3000 +/- 200 lux with a hydraulic retention time (HRT) of 24-72 h. The hydrogen production rate and the broth characteristics varied significantly in the flow direction. The hydrogen production rate was highest in chamber #1, and lower in chambers #2-#4 at an HRT of 72 h, while the peak production rate shifted to the latter chambers as the HRT was shortened. The overall H-2 production rate increased as HRT decreased, but was not consistent with the predictions that were based on the complete-mixing assumption. (C) 2017 Elsevier Ltd. All rights reserved.