Production of bio-hydrogen from bulgur processing industry wastewater

Abstract

ABSTRACT Hydrogen as a clean energy source has a great attention worldwide due to decreasing fossil fuel reserves and rising environmental pollution. Although many types of wastewater have been tested as a cheap substrate in biohydrogen production, the bulgur processing industry wastewater which contains high organic matter has not yet evaluated. This study highlights bulgur processing industry wastewater as a potential substrate for biohydrogen production by dark fermentation. The effects of anaerobic sludge pretreatment methods (thermal and ultrasonic), applying durations (5 and 15 min) for these pretreatment methods, and the ratio of inoculum: substrate (I:S) (1:2, 1:3, 1:4, 1:6 gVS.g−1VS) were investigated in lab-scale batch reactors (at 35°C, pH = 5.5, 16 days of incubation time). Biochemical hydrogen potential (BHP) test results showed that the maximum cumulative bio-hydrogen production of 90.83 mL H2 g−1 VSadded was obtained from inoculums thermally pretreated and a ratio of I:S ratio = 1:3 on day 16. In addition, the highest yield of bio-hydrogen was 54.076 mL H2 g−1 VSadded obtained from inoculums pretreated by ultrasonic method and ratio of I:S = 1:6. Kinetics from the Gompertz model was used to evaluate the determination of cumulative hydrogen production. Gompertz model showed that BHP tests and simulated hydrogen production potential (Hmax) values were approximately similar to the experimental ones.