Anaerobic Hydrogen Fermentation Research Articles

Production of biohydrogen and green platform compound 2, 5-furandicarboxylic acid using rice straw hydrolysate

Lignocellulosic hydrolysate contains several inhibitors that hinder downstream biological processes. The immobilized strain Burkholderia sp. H-2 was used in this study to biodetoxify real rice straw hydrolysate and biotransform 5-hydroxymethylfurfural (5-HMF), an inhibitor, into 2, 5-furandicarboxylic acid (FDCA), a valuable platform compound. An electrodialysis with bipolar membranes (EDBM) system was applied to recover FDCA and perform secondary detoxification of the biodetoxified real rice straw hydrolysate. The rice straw hydrolysate after biodetoxification and EDBM treatment was used for anaerobic dark fermentative hydrogen production. The immobilized Burkholderia sp. H-2 could completely biotransform 1843 mg/L 5-HMF into 1532 mg/L FDCA within 24 h when the 2-fold diluted rice straw hydrolysate was used as the feedstock. The optimal EDBM system parameters to recover FDCA were a hydrolysate pH of 6, operated at a current density of 17.86 mA/cm2. The FDCA recovery efficiency was 44.6 %, when using the biodetoxified real rice straw hydrolysate as the EDBM feedstock. The rice straw hydrolysate after biodetoxification and EDBM treatment had better biohydrogen production performance than the undetoxified and biodetoxified rice straw hydrolysates.

Surfactant enhances anaerobic fermentative hydrogen sulfide production: Changes in sulfur-containing organics structure and microbial community

The presence of surfactants in waste activated sludge (WAS) system is generally regarded as beneficial to sludge treatment such as enhancing sludge dewatering and improving value-added fermentation products generation. However, in this study, it was firstly found that sodium dodecylbenzene sulfonate (SDBS, a typical surfactant) obviously increased toxic hydrogen sulfide (H2S) gas production from WAS anaerobic fermentation at environmentally relevant concentrations. Experimental results showed that H2S production from WAS significantly increased from 53.24 × 10−3 to 111.25 × 10−3 mg/g volatile suspended solids (VSS) when SDBS level increased from 0 to 30 mg/g total suspended solid (TSS). It was found that SDBS presence destroyed WAS structure and enhanced sulfur containing organics release. SDBS reduced the proportion of α-helix structure, damaged disulfide bridges and protein conformation, and effectively destroyed protein structure. SDBS promoted sulfur containing organics degradation and provided more readily hydrolyzed micro-molecule organics for sulfide production. Microbial analysis showed that SDBS addition enhanced the abundance of functional genes encoding protease, ATP-binding cassette transporters, and amino acids lyase, enhanced the activities and abundance of hydrolytic microbes, thus increased sulfide production from the hydrolysis of sulfur containing organics. Compared with the control, 30 mg/g TSS SDBS increased organic sulfurs hydrolysis and amino acids degradation by 47.1 % and 63.5 %, respectively. Key genes analysis further showed that SDBS addition promoted sulfate transport system and dissimilatory sulfate reduction. SDBS presence also lowered fermentation pH, promoted the chemical equilibrium transformation of sulfide, thus increased H2S gas release.

Bio-hydrogen production by dark anaerobic fermentation of organic wastewater.

Using organic wastewater to produce hydrogen by fermentation can generate clean energy while treating wastewater. At present, there are many inhibitory factors in the hydrogen production process, resulting in unsatisfactory hydrogen yield and hydrogen concentration during the fermentation process, and there are still great obstacles to the industrial promotion and commercial application of organic wastewater fermentation hydrogen production. This paper summarizes the hydrogen production of organic wastewater dark anaerobic fermentation technology. The current anaerobic fermentation hydrogen production systems and technologies are summarized and compared, and the factors and potential conditions that affect the performance of hydrogen production are discussed. The further requirements and research priorities for the market application of fermentation biohydrogen production technology in wastewater utilization are prospected.

The conversion of biomass to fuels via cutting-edge technologies: Explorations from natural utilization systems

Biomass can be used to manufacture both hydrocarbon fuels and chemical compounds such as rubber, alcohols, lipid-based products, sugars, etc. Due to their abundant supply and lower greenhouse gas emissions, fuels derived from biomass have received much attention in recent years. Biofuels can be made from grasses, agricultural waste, animal waste and trash, old oils, and other organic things. The characteristics of various feedstocks and fuels, as well as the techniques for converting biomass to biofuels, physical and chemical parameters, and limitations that affect biomass to fuel conversion, are all discussed. pH, temperature, and residence time are all process parameters. Other chemical factors include the availability of carbon, nutrients, acid and alkaline hydrolysis agents, phenolic inhibitors, and sugars produced throughout the process. The list of obstacles to biomass bioconversion includes reduced particle size, crystallinity, fermentation inhibitory byproducts, cellulase deactivation, yeast ethanol tolerance, and sugar co-fermentation. The research and development of biomass-to-energy conversion technology have been accelerating significantly, according to this review. The choice of the conversion method depends on the type and quality of the biomass, the final energy form, environmental requirements, economic conditions, and project-specific considerations. Biowaste is initially improved (depending on the conditions). This process includes size reduction, densification, drying, and torrefaction. The two most popular conversion methods for biomass to energy are thermochemical and biochemical. Utilizing the power of microorganisms, biochemical conversion transforms biomass into liquid or gaseous fuels. The processes of anaerobic digestion, fermentation, and photobiological hydrogen generation are currently the most widely used biochemical technologies. Recent advancements in recombinant DNA technology and protein engineering, as well as future technology like extraction, and application towards green, are targeted at addressing bioconversion restrictions.

A lab fermenter level study on anaerobic hydrogen fermentation using potato peel waste: effect of pH, temperature, and substrate pre-treatment

A lab fermenter level study on anaerobic hydrogen fermentation using potato peel waste: effect of pH, temperature, and substrate pre-treatment

High potential of Rhizopus treated rice bran waste for the nutrient-free anaerobic fermentative biohydrogen production

In this study, Rhizopus oligosporus MTCC 556 (Rhizopus) treated rice bran was utilized for the anaerobic bacterial fermentative hydrogen production. The Enterobacter aerogenes MTCC 2822 with nutrients addition fermented the treated rice bran to give hydrogen yield of 5.4 mmol H2/g of biomass. A closely similar hydrogen yield of 4.6 mmol H2/g of biomass was obtained from the treated rice bran under the condition without nutrients addition, suggesting the potential of the fungus treatment to produce hydrogen from nutrient-free fermentation. The pretreated rice bran showed efficient hydrogen production upon anaerobic fermentation without nutrients addition. The Rhizopus pretreated biomass can provide required nutrients for the enhancement of hydrogen yield by anaerobic fermentation. The Rhizopus pretreatment of rice bran enhanced the hydrogen production under nutrient-free conditions which reduced the overall production cost. The findings provide a promising solution to efficiently utilize the rice bran waste for low cost hydrogen production.

Optimization (Substrate and pH) and Anaerobic Fermentative Hydrogen Production by Various Industrial Wastes Isolates Utilizing Biscuit Industry Waste as Substrate

Optimization (Substrate and pH) and Anaerobic Fermentative Hydrogen Production by Various Industrial Wastes Isolates Utilizing Biscuit Industry Waste as Substrate

Comparison of bio-hydrogen production yield capacity between asynchronous and simultaneous saccharification and fermentation processes from agricultural residue by mixed anaerobic cultures

Taken common agricultural residues as substrate, dark fermentation bio-hydrogen yield capacity from asynchronous saccharification and fermentation (ASF) and simultaneous saccharification and fermentation (SSF) was investigated. The highest hydrogen yield of 472.75mL was achieved with corncob using ASF. Hydrogen yield from corn straw, rice straw, corncob and sorghum stalk by SSF were 20.54%,10.31%,13.99% and 5.92% higher than ASF, respectively. The experimental data fitted well to the modified Gompertz model. SSF offered a distinct advantage over ASF with respect to reducing overall process time (60h of SSF, 108h of ASF). Meanwhile, SSF performed better than SSF with respect to shortening the lag-stage. The major metabolites of anaerobic fermentation hydrogen production by ASF and SSF were butyric acid and acetic acid.

Improvement of hydrogen fermentation of galactose by combined inoculation strategy

This study evaluated the feasibility of anaerobic hydrogen fermentation of galactose, a red algal biomass sugar, using individual and combined mixed culture inocula. Heat-treated (90°C, 30min) samples of granular sludge (GS) and suspended digester sludge (SDS) were used as inoculum sources. The type of mixed culture inoculum played an important role in hydrogen production from galactose. Between two inocula, granular sludge showed higher hydrogen production rate (HPR) and hydrogen yield (HY) of 2.2L H2/L-d and 1.09mol H2/mol galactoseadded, respectively. Combined inoculation (GS+SDS) led to an elevated HPR and HY of 3.1L H2/L-d and 1.28mol H2/mol galactoseadded, respectively. Acetic and butyric acids are the major organic acids during fermentation. Quantitative polymerase chain reaction (qPCR) revealed that the mixed culture generated using the combined inoculation contained a higher cluster I Clostridium abundance than the culture produced using the single inoculum.

Comparison of micro-aerobic and anaerobic fermentative hydrogen production from corn straw

Micro-aerobic and anaerobic fermentative hydrogen productions were carried out in bottle tests (150 mL) and scale-up bioreactors (10 L) using corn straw as a substrate. Hydrogen yield of 41.6 mL/g (volatile solid, VS) obtained from scale-up experiment with optimal oxygen addition of 0.28 mL/(g (total solid, TS)·day) was higher than that of 28.9 mL/g VS without additional oxygen. Oxidation reduction potential was−300∼−150 mV for micro-aerobic fermentation, where it was−560∼−360 mV for anaerobic fermentation. The micro-aerobic condition had strong buffering ability and could tolerate a greater accumulation of volatile fatty acid. Both micro-aerobic and anaerobic hydrogen production were butyric acid-type fermentation. Microbial community analysis indicated the presence of Citrobacter sp. and Escherichia sp., which were unique to micro-aerobic system, as well as classical Enterococcus, Bacteroides, Peptoclostridium, Clostridium genera that existed in both micro-aerobic and anaerobic fermentation.

Effect of Methanogenesis of Residue from Thermal Pre-treatment Sludge by Anaerobic Fermentative Hydrogen Production

The municipal sludge of Wastewater treatment plants generate a mass of municipal sludge is becoming an extremely environment issue. Effective utilization of the sludge to generate benefits concern many scholars. This research worked systematically to study the condition of gas production of sludge by thermal pre-treatment and compared a large differance among the maximum cumulative methane production in the sludge of high temperature thermal treatment. The inoculum via 75°C thermal pretreatment for 10min mixed sludge substrates by different temperature pre-treatment for 30min. The optimum methane production was obtained from 160°C, and the 120°C was worse in the methane produciton. The max accumulated hydrogen and methane production were 3.57mL and 235.97mL respectively of 160°C; the max accumulated methane production was 193.24mL of 120°C. Compared the metabolic process of anaerobic fermentation of methane, the degradation of organic matter in the sludge substrate by 160°C for heat treatment was better than that of 120°C.

Feasibility of enriched mixed cultures obtained by repeated batch transfer in continuous hydrogen fermentation

This research investigated the suitability of enriched mixed cultures (EMC) for anaerobic hydrogen fermentation in continuous operation. EMC was prepared after four successive transfers in PYG (peptone, yeast extract and galactose) medium in batch cultivation. The peak hydrogen production rate (HPR) and hydrogen yield (HY) of 770 ± 10 mL H2/L-d and 1.05 ± 0.06 mol H2/mol galactoseadded, were attained respectively. There forward a continuously stirred tank reactor (CSTR) has been operated with the substrate concentration of 15 g/L at a hydraulic retention time (HRT) of 12 h for more than 15 days by using EMC. The performance showed that HPR and HY were fluctuated significantly during the operation and the average values were 1710 ± 250 mL H2/L-d and 0.82 ± 0.12 mol H2/mol galactoseadded, respectively. The soluble metabolic products analysis revealed that butyrate, lactate and acetate were the dominant metabolic products with less quantity of propionic and formic acids. The microbial community structure has been determined by next generation DNA sequencing technique and revealed Clostridium sp. was the dominant microbial consortium during repeated batch transfer, whereas Sporolactobacillus sp. was the major population in continuous operation. This study demonstrates that operational mode (batch and continuous) significantly influence the microbial diversity and hydrogen production, and EMC obtained by repeated process may not be suitable for continuous hydrogen fermentation.

Anaerobic Hydrogen Fermentation and Membrane Bioreactor (MBR) for Decentralized Sanitation and Reuse-Organic Removal and Resource Recovery

The purpose of this study is to evaluate integrated anaerobic hydrogen fermentation and membrane bioreactor (MBR) for on-site domestic wastewater treatment and resource recovery. A synthetic wastewater (COD 17,000 mg/L) was used as artificial brown water which will be discharged from urine diversion toilet and fed into a continuous stirred tank reactor (CSTR) type anaerobic reactor with inclined plate. The effluent of anaerobic reactor mixed with real household grey water (COD 700 mg/L) was further treated by MBR for reuse. An optimum condition maintained in anaerobic reactor was HRT of 8 hrs, pH 5.5, SRT of 5 days and temperature of 37˚C. COD removal of 98% was achieved from the overall system. Total gas production rate and hydrogen content was 4.6 L/day and 52.4% respectively. COD mass balance described the COD distribution in the system via reactor byproducts and effluent COD concentration. The results of this study asserts that, anaerobic hydrogen fermentation combined with MBR is a potent system in stabilizing waste strength and clean hydrogen recovery which could be implemented for onsite domestic wastewater treatment and reuse.

Effect of short-time hydrothermal pretreatment of kitchen waste on biohydrogen production: Fluorescence spectroscopy coupled with parallel factor analysis

The enhancement of bio-hydrogen production from kitchen waste by a short-time hydrothermal pretreatment at different temperatures (i.e., 90°C, 120°C, 150°C and 200°C) was evaluated. The effects of temperature for the short-time hydrothermal pretreatment on kitchen waste protein conversion and dissolved organic matter characteristics were investigated in this study. A maximum bio-hydrogen yield of 81.27mL/g VS was acquired at 200°C by the short-time hydrothermal pretreatment during the anaerobic fermentative hydrogen production. Analysis of the dissolved organic matter composition showed that the protein-like peak dominated and that three fluorescent components were separated using fluorescence excitation–emission matrix spectra coupled with the parallel factor model. The maximum fluorescence intensities of protein-like components decomposed through the parallel factor analysis has a significant correlation with the raw protein concentration, showed by further correlation analysis. This directly impacted the hydrogen production ability.

Starch: a potential substrate for biohydrogen production

Hydrogen is a clean energy carrier with great potential to be an alternative fuel. Anaerobic hydrogen fermentation seems to be more favorable, since hydrogen is yielded at high rates and various organic waste and wastewater enriched with carbohydrates as substrate result in low cost for hydrogen production. Abundant biomass from various industries could be a source for biohydrogen production where combination of waste treatment and energy production would be an advantage. Carbohydrate-rich nitrogen-deficient solid wastes such as starch residues can be used for hydrogen production by using suitable bioprocess technologies. Alternatively, converting biomass into gaseous fuels, such as biohydrogen, is possibly the most efficient way to use these agroindustrial residues. This review summarizes the potential of starch agroindustrial residues as a substrate for biohydrogen production. Types of potential starch agroindustrial residues, recent developments and bio-processing conditions for biohydrogen production will be discussed. Copyright © 2014 John Wiley & Sons, Ltd.

Influence of carbon/nitrogen ratio on the anaerobic fermentative hydrogen production with cow dung compost

In the anaerobic fermentation process, the carbon/nitrogen (C/N) ratio in the medium is a critical factor representing nutrient balance, which is important for cell synthesis, growth, and metabolism. The cow dung compost was co-digested, respectively, with glucose and apple pomace (AP) in the batch experiments to investigate the effects of C/N ratio on fermentative hydrogen production. For the co-digestion of glucose and cow dung compost, the cumulative hydrogen yield (CHY) peaked with 1232.7 ml/L-culture at a C/N ratio of 9.3, and the concentrations of glucose and cow dung compost were 5.0 g/l and 180.0 g/l, respectively. However, the maximum CHY reached 1398.0 ml/L-culture for the co-digestion of cow dung compost and AP, and the C/N ratio was 10.6. In addition, when we used glucose as the single substrate and the microorganisms existing in the electrode of pH meter as bacteria source which was from previous hydrogen production with cow dung compost, at a C/N ratio of 10.3, the CHY peaked with 945.7 ml/L-culture, and the concentration of glucose was 10.0 g/l. Meanwhile, at the optimum C/N ratio, the main component of liquid end-products was butyrate.

음식물류 폐기물의 혐기성 수소 발효 시 열처리에 따른 성능 및 미생물 특성 평가

Abstract >> This study was conducted to investigate the effect of thermal pre-treatment on bio-hydrogen fromfood waste. Two continuous reactors operated and VFAs(volatile fatty acids) production and microbial communitieswere analyzed. The average hydrogen yield was 0.50 and 0.33mol H 2 /mol hexose added in thermally treated food added reactor(R1) and control(R2), respectively. Butyrate concentration was similarly 7,500mg/L in both reactors,but two times higher lactate concentration was observed in R2(3,800mg/L). The results of FISH(fluorescence in situ hybridization) showed that the relative microorganism to hydrogen producing bacteria was 78 and 27% inR1 and R2, respectively. Key words : Anaerobic hydrogen fermentation(혐기성 수소 발효), Food waste(음식물류 폐기물), Fluorescencein situ hybridization analysis(형광 원위치 부합법), Volatile fatty acids(휘발성 지방산), Thermal pre-treatment( 열전처리) † Corresponding author : chaeyoung@suwon.ac.kr [ 접수일 : 2013.11.29 수정일 : 2014.2.19 게재확정일 : 2014.2.28 ]Copyright ⓒ 2014 KHNES

Effect of Substrate Concentration on Hydrogen Production from Fermentation of Sugar Wastewater

The biological hydrogen production by the sugar wastewater is an effective way to achieve the reclamation. In this paper, the effect of substrate concentration on the hydrogen production is discussed through employing the self-made continuous flow anaerobic fermentation hydrogen production reactor, taking the sludge in urban sewage treatment plant as the inoculated sludge and the simulated sugar wastewater as the substrate. The experimental results show that the best hydrogen production effect can be obtained when the temperature is (37±1) °C, HRT is 7h, the water alkalinity is around 530mg/L and the substrate concentration is 5000mg/L, namely the organic load is 60kgCOD/(m3·d). The volumes of gas production and hydrogen production both reach the maximum. The average values are respectively 36.2L/d and 21.8L/d. The obtained hydrogen production rate is 0.93kgCOD/(m3·d). During the whole process, the proportion of volatile acid composition remains stable, which is the butyric acid-type fermentation. When the concentration of COD is increased to 6000-8000mg/L, the ability of hydrogen production of system will be significantly dropped due to the increase of pH of system. The hydrogen production performance can be restored through artificially and timely lowering the water alkalinity. However, the hydrogen production rate will be decreased compared to the previous situation.

Research of Anaerobic Fermentation Hydrogen Production Process by Continuous Flow from Contained Sugar Wastewater

The basal fermentation time and hydraulic retention time were systemically investigated about anaerobic fermentation production hydrogen process by continuous flow which is based on activated sludge for a basic strain and simulating sucrose wastewater for a substrate in a continuous stirred tank reactor. The highest hydrogen production rate was got at the fermentation time of 15h for and 6h for hydraulic retention time. The optimum run acidity (pH = 4.5 5.0) was kept through their own system circulation to hold the system state of high-speed and continuous hydrogen production. The results can really laid the groundwork for the anaerobic fermentation production hydrogen process by continuous flow from contained sugar wastewater from the laboratory research towards industrialization.

열처리를 통한 미세조류로부터 바이오수소 생산 향상

Abstract >> This study was conducted to increase the amount of bio-hydrogen production from microalgae(Chlorellavulgaris) in batch reactors by thermal pre-treatment. The optimization of thermal pre-treatment was conducted usingstatistic experimental design of response surface methodology. Two experimental parameters of temperature and reaction time were considered. The optimization condition was founded at the coded variables of corresponding to the experimental of heating temperature of 95.6℃ and reaction time of 57.9 min, respectively.Under the optimal condition, the maximum hydrogen production was predicted to 25.3mL H 2 /g dry cell weight(dcw), which was 9.1 times higher value of control(2.8mL H 2 /g dcw). Key words : Anaerobic hydrogen fermentation(혐기성 수소 발효), Maximum hydrogen production(최대 수소 전환율), Microalgae(미세조류), Response surface methodology(반응표면분석법), Thermal pre-treatment(열전처리) † Corresponding author : chaeyoung@suwon.ac.kr [ 접수일 : 2013.7.7 수정일 : 2013.7.30 게재확정일 : 2013.8.31 ]Copyright ⓒ 2013 KHNES