Inhibition of the Hydrolytic Phase in the Production of Biohydrogen by Dark Fermentation of Organic Solid Waste

Abstract

In this paper, a destabilization episode in a semicontinuous dry thermophilic acidogenic reactor was induced. The reactor was fed with different mixtures of organic fraction of municipal solid waste (OFMSW) and food waste (FW). The aim was to determinate the effect of the organic loading rate (OLR) and cosubstrate ratio on biohydrogen production by dark fermentation. OLR was increased from 21.0 to 88.8 g TVS/L/day testing three mixture ratios (OFMSW:FW) from 80:20 to 50:50 and four hydraulic retention times (HRTs; 6.6, 4.4, 2.4, and 1.9 days). Results have shown that an increment in the OLR (from 21.0 to 59.8 g TVS/L/day) and FW proportion (from 80:20 to 50:50) improves the yield process in terms of solubilized organic matter. However, from 50:50 ratio combined with OLRs higher than 70.3 g TVS/L/day and HRTs lower than 4.4 days showed a clear destabilization episode due to an imbalance of the hydrolytic phase. This fact has been corroborated by the values of two indirect parameters, “nonsolubilized carbon” and “acidogenic substrate as carbon”.

Synergistic Biohydrogen Production from Flower Wastes and Sewage Sludge

“…Hydrogen is a sustainable energy source because of the advantages of having a high heating value (122 MJ/kg) and clean combustion end product (water) . Recently, hydrogen produced by biological dark fermentation has gained more and more attention due to the advantages of having a fast reaction rate, low energy demand, and simple operation conditions . More attractively, dark fermentation processes can directly utilize various kinds of organic wastes as feedstock to produce hydrogen and recover resources, − which simultaneously achieves waste treatment and renewable energy generation.…”

Evaluating the Effectiveness of Adding Chicken Manure in the Anaerobic Mesophilic Codigestion of Sewage Sludge and Wine Distillery Wastewater: Kinetic Modeling and Economic Approach

“…The concentration of total volatile fatty acids was calculated as the weighted sum (on a molecular weight basis) of the individual volatile fatty acid concentrations. 9,24 The volume of biogas was measured with a pressure sensor at the start of each sampling event in the headspace of the biochemical methane potential bottles, as in Zahedi et al 25 Cumulative gas production was calculated from the increase in pressure in the headspace volume (130 mL). The composition of the gas was determined on a gas chromatographer (GC-2010 Shimadzu).…”

“…Prior to injection, the samples resulting from lixiviation were filtered: first through a 0.47 μm Teflon filter and then through a similar 0.22 μm filter. The concentration of total volatile fatty acids was calculated as the weighted sum (on a molecular weight basis) of the individual volatile fatty acid concentrations. , …”

“…This waste is usually employed in cocomposting, soil conditioning, and anaerobic digestion (AD) . As CM contains nitrogen in high concentrations, soil conditioning (without any treatment) is not a good management tool as major accumulation of nitrate in the soil profile increases the nitrate concentration in groundwater, risking pollution of the environment and harm to the human body. , Conversion of CM into bioenergy via AD has become increasingly attractive in recent decades. − AD is a widely used process throughout the world, being effective in removing pathogens, reducing the amount of organic matter and for producing renewable energy in the form of biogas. − CM has a high organic matter content that is highly biodegradable and can be used as a substrate to produce bioenergy via AD. However, it also contains solids and nitrogen in high concentrations, which may lead to inhibition of the AD process. ,− This means that it is necessary to use water or other cosubstrates with a higher carbon but lower solids content.…”

Influence of the total concentration and the profile of volatile fatty acids on polyhydroxyalkanoates (PHA) production by mixed microbial cultures

“…Thus, acidogenic anaerobic digestion (AAD) or commonly DF is a variation of the classic biological process of anaerobic digestion in which the stages that involve methanogenesis do not occur since operating conditions are used to prevent it. Thus, the microorganisms involved in DF transform organic matter into short-chain volatile fatty acids (VFAs) and produce biogas rich in carbon dioxide and mainly hydrogen [19,20].…”