Batch anaerobic co-digestion of cow manure and waste milk in two-stage process for hydrogen and methane productions

Abstract

Anaerobic co-digestion of cow manure (CM) and waste milk (WM), produced by sick cows during treatment with antibiotics, was evaluated in two-stage process under thermophilic condition (55 °C) to determine the effect of WM addition on hydrogen (H2) and methane (CH4) production potentials, volatile solids (VS) removal, and energy recovery. Six CM to WM VS ratios of 100:0, 90:10, 70:30, 50:50, 30:70, and 10:90 were examined using 1-L batch digesters. The WM VS ratio of 30 % was found to be the minimum limit for significant increases in specific H2 and CH4 yields, and VS removal as compared to digestion of manure alone (P < 0.05). The highest specific H2 and CH4 yields, VS removal and energy yield were 38.2 mL/g VS, 627.6 mL/g VS, 78.4 % and 25,459.8 kJ/kg VS, respectively, in CM:WM 30:70. Lag phases to H2 and CH4 productions were observed in CM-WM mixtures, increased with increasing the amount of WM in the feedstock and were greater than 72 h in CM:WM 50:50 and 30:70. The digestion system failed in CM:WM 10:90. The results suggest that CM:WM 30:70 was optimum, however, due to limited amount of WM usually generated and long lag phase at this ratio which may make the process uneconomical, CM:WM 70:30 is recommended in practice.

Anaerobic Process for Bioenergy Recovery From Dairy Waste: Meta-Analysis and Enumeration of Microbial Community Related to Intermediates Production

“…Comparing the H 2 and CH 4 production with the literature, the production in this study (54.34 ± 0.15 L H 2 kg VS -1 and 16.74 ± 0.71 L CH 4 kg VS -1 ) were higher than that reported by Pagliano et al (2018) (8.9 L H 2 kg VS -1 and 2.2 L CH 4 kg VS -1 ) using dairy waste as substrate and operating in batch mode. Different operating condition can promote the CH 4 production, as reported by Lateef et al (2014) that studied an anaerobic sequencing batch reactor (ASBR) fed with dairy waste achieving 35.6 L H 2 Kg VS -1 and 627 L CH 4 Kg VS -1 .…”

Possible application of biohydrogen technologies as electricity sources in Indonesian remote areas

“…Other studies indicate that the conversion of tropical biomass into energy has an efficiency of less than 50% based on the carbon content [23,24]. Therefore, 53 L of milk waste or 52 L of soy sauce could be converted into 650 L of hydrogen gas on average, which would generate 1 kW of electrical power per hour [25,26]. Although the waste needed for electricity power generation is a large amount in quantity, it is freely available because it is a waste.…”

Critical review on biological treatment strategies of dairy wastewater

“…The ASP with 5 d of incubation period along with maintenance of BOD at 95% shows an effective removal of organic compounds from dairy effluents. This system functions beneficially in the pH range of about 9-10.5 [53]. Activated granular sludge is a notable advancement in the ASP, furthermore, in this method a set of the novel microbial group works on the expulsion of C, N, P and different organic compounds present in the effluent.…”