Biohydrogen Production Technology Research Articles

Biological fermentation pilot-scale systems and evaluation for commercial viability towards sustainable biohydrogen production

Featuring high caloric value, clean-burning, and renewability, hydrogen is a fuel believed to be able to change energy structure worldwide. Biohydrogen production technologies effectively utilize waste biomass resources and produce high-purity hydrogen. Improvements have been made in the biohydrogen production process in recent years. However, there is a lack of operational data and sustainability analysis from pilot plants to provide a reference for commercial operations. In this report, based on spectrum coupling, thermal effect, and multiphase flow properties of hydrogen production, continuous pilot-scale biohydrogen production systems (dark and photo-fermentation) are established as a research subject. Then, pilot-scale hydrogen production systems are assessed in terms of sustainability. The system being evaluated, consumes 171,530 MJ of energy and emits 9.37 t of CO2 eq when producing 1 t H2, and has a payback period of 6.86 years. Our analysis also suggests future pathways towards effective biohydrogen production technology development and real-world implementation.

Evaluation of Biohydrogen Production Depending on the Substrate Used—Examples for the Development of Green Energy

Biohydrogen production is a promising alternative to replace fossil fuels in an environmentally friendly way. In addition to the many available renewable energy sources, the production of “colored” hydrogen and biohydrogen occupies an irreplaceable position due to the undeniable availability of biomass and the need to manage food waste (FW). This article presents the current state of biohydrogen production technology—examples on continents (America, Africa, Asia, Australia and Oceania) and in Europe in terms of the efficiency of dark methane fermentation (CH4). Biophotolysis processes leading to the production of biohydrogen are indicated: directly and indirectly. The mechanism of the fermentation process of obtaining hydrogen and two-stage hydrogen fermentation are presented. The novelty of this article is the development of innovative trends in the development of the biohydrogen industry in Europe. Various models of the biohydrogen process are presented for different raw materials and proportions of substrates used in co-fermenters. Researchers from China are the undisputed pioneers in the use of renewable energy sources. However, improved energy self-sufficiency and environmental impacts are reflected in the growing number of pilot installations operating in European countries. This also gives hope for rapid progress towards full animal and FW management also in Poland.

Evaluating the feasibility of carbon fiber brush for improving biohydrogen production in acidogenic dark fermentation

Dark fermentation is a promising technology for biohydrogen (bioH2) production. Augmenting the dark fermentation process with conductive materials has drawn significant research interests improving the bioH2 yield. This study evaluated the feasibility of using carbon fiber brush (CB) as an additive to increase the efficiency of mesophilic dark fermentation using glucose as substrate and heat-shock pretreated anaerobic sludge as inoculum. Effect of electrode packing density on bioH2 yield, soluble metabolite product formation, and substrate degradation was investigated. Maximal bioH2 yield of 334.6 mL/g-glucose was obtained using medium-sized CB with 72.5% higher than the control (194 mL/g-glucose) and butyrate-type fermentation was the dominant metabolic pathway. Further, enhanced concentrations of proteins and polysaccharides on CB biofilm suggested the critical role of extracellular polymeric substances in microbial electron transfer. This was supported via electron transport activity in CB biofilm. Finally, microbial community analysis revealed a selective enrichment of the potentially electroactive Clostridium_sensu_stricto_1 on the CB (56.6%) compared to 40.9% abundance in control. Insights gained from this study demonstrated that CB aided dark fermentation can be an economical and environmentally benign strategy for improving bioH2 yield.

Algal Hydrogen Production and Exopolysaccharide Patterns in Chlorella–Bacillus Inter-Kingdom Co-Cultures

Biohydrogen production from wastewater using eukaryotic green algae can be facilitated by appropriately selected bacterial partners and cultivation conditions. Two Chlorella algal species were chosen for these experiments, based on their robust growth ability in synthetic wastewater. The applied three Bacillus bacterial partners showed active respiration and efficient biomass production in the same synthetic wastewater. Bacillus amyloliquefaciens, Bacillus mycoides, and Bacillus cereus as bacterial partners were shown to specifically promote algal biomass yield. Various inter-kingdom co-culture combinations were investigated for algal–bacterial biomass generation, for co-culture-specific exopolysaccharide patterns, and, primarily, for algal biohydrogen evolution. Chlorella sp. MACC-38 mono- and co-cultures generated significantly higher biomass compared with that of Chlorella sp. MACC-360 mono- and co-cultures, while in terms of hydrogen production, Chlorella sp. MACC-360 co-cultures clearly surpassed their Chlorella sp. MACC-38 counterparts. Imaging studies revealed tight physical interactions between the algal and bacterial partners and revealed the formation of co-culture-specific exopolysaccharides. Efficient bacterial respiration was in clear correlation with algal hydrogen production. Stable and sustainable algal hydrogen production was observed in synthetic wastewater for Chlorella sp. MACC-360 green algae in co-cultures with either Bacillus amyloliquefaciens or Bacillus cereus. The highest algal hydrogen yields (30 mL H2 L−1 d−1) were obtained when Chlorella sp. MACC-360 was co-cultured with Bacillus amyloliquefaciens. Further co-culture-specific algal biomolecules such as co-cultivation-specific exopolysaccharides increase the valorization potential of algal–bacterial co-cultures and might contribute to the feasibility of algal biohydrogen production technologies.

Comparative study on biohydrogen production by newly isolated Clostridium butyricum SP4 and Clostridium beijerinckii SP6

The hydrogen-producing bacteria SP4 and SP6 were isolated from the compost and identified by 16S rRNA gene sequencing as Clostridium butyricum and Clostridium beijerinckii, respectively. A comparative study on the biohydrogen-producing activity of the isolated strains was carried out using mono-, di- and tri-saccharides belonging to both hexoses (maltose, glucose, mannose, fructose, lactose, galactose, sucrose, raffinose, cellobiose) and pentoses (xylose). To assess the biotechnological significance, real wastewater rich in sugars (cheese whey, confectionery wastewater, sugar beet processing wastewater) was also used as a substrate. C. butyricum SP4 fermented sugars with a yield of 0.93–1.52 mol H2/mol hexose (pentose); the maximum yield was obtained from fructose, the minimum – from raffinose and cellobiose. The most preferred substrate for C. beijerinckii SP6 was sucrose with a yield of 1.76 mol H2/mol hexose, while cellobiose yielded only 0.64 mol H2/mol hexose. Overall, the efficiency of converting wastewater to H2 by C. butyricum SP4 was also slightly lower (66–93 ml H2/g chemical oxygen demand (COD)) than that of C. beijerinckii SP6 (76–103 ml H2/g COD). Even though the main soluble metabolite products (SMPs) for both isolates were acetate and butyrate, C. butyricum SP4 also produced a significant amount of ethanol (up to 21.5% of SMPs) and formate (up to 32.5% of SMPs), and C. beijerinckii SP6 – lactate (up to 25% of SMPs). A distinctive feature of C. beijerinckii SP6 was a significantly lower (almost 2 times) yield of SMPs, while C. butyricum SP4 had a higher rate of H2 production according to the results obtained from the kinetic study using the modified Gompertz equation and the first order equation. Analysis of Spearman's rank correlation coefficients revealed a statistically significant relationship between the kinetic parameters of H2 production and the concentration of butyrate and the final pH of the medium for C. butyricum SP4, and with the concentration of ethanol for C. beijerinckii SP6. These findings provide valuable information on the metabolic capabilities of the most studied hydrogen-producing representatives of the Clostridium genus for their use in optimizing the technology for biohydrogen production by dark fermentation of various organic wastes.

Hydrogen recovery cascade from pretreated rice straw and its fermentative residuals using step-up potential-based sulfate reducing bacteria-bioelectrochemical system

Despite the availability of well-proven biohydrogen production technology, the uncapping of the biological theoretical hydrogen yield is still a challenge. This study explores the stimulation of step-up applied potential for hydrogen production in a sulfate-reducing bacteria-based bioelectrochemical system (SRB-BES), a sustainable and promising technology for organic waste recycling with resource recovery. This research focused on the application of a low applied potential to recover H2 from pretreated rice straw and its residual fermentative by-products. An applied potential of −40 mV could proficiently recover 1.5 times higher hydrogen from pretreated rice straw by completely inhibiting methanogens. The residual fermentative byproducts obtained at the first stage were further used in extra H2 recovery at a step-up applied potential of −150 mV, −300 mV, and −450 mV. The H2 recovery from fermentative residuals shows maxima at −300 mV. The acetic acid and iso-butyric acid production of 52.89 ± 15.67 and 56.93 ± 11.81 mM at −300 mV and −450 mV respectively contribute majorly to volatile fatty acids (VFAs). The more electronic equivalents of 2024.34 (mM) in R-450mV in comparison to 1850.803 (mM) in R-40mV (effluent recovered from AD-MEC) indicate the involvement of the higher applied potential in chain elongation of VFAs. So, optimization of step-up potential could lead to the bioelectrochemical synthesis of the desired fatty acids through chain elongation deserving various applications with hydrogen recovery. The gaseous data obtained were verified by Richard, Logistic, and modified Gompertz kinetic models to check H2 prediction validity using cumulative H2 production. This study demonstrated the technical foundation with a novel approach to maximize hydrogen recovery from the fermentation residuals by step-up applied potential.

Synergistic strategy for the enhancement of biohydrogen production from molasses through coculture of Lactobacillus brevis and Clostridiumsaccharobutylicum

This study aimed to evaluate the capacity of different inoculum sources and their bacterial diversity to generate hydrogen (H2). The highest Simpson (0.7901) and Shannon (1.581) diversity indexes for H2-producing bacterial isolates were estimated for sewage inocula. The maximum cumulative H2 production (Hmax) was 639.6 ± 5.49 mL/L recorded for the sewage inoculum (SS30) after 72 h. The highest H2-producing isolates were recovered from SS30 and identified as Clostridium saccharobutylicum MH206 and Lactobacillus brevis MH223. The Hmax of C. saccharobutylicum, L. brevis, and synergistic coculture was 415.00 ± 24.68, 491.67 ± 15.90, and 617.67 ± 3.93 mL/L, respectively. The optimization process showed that the Hmax (1571.66 ± 33.71 mL/L) with a production rate of 58.02 mL/L/h and lag phase of 19.33 h was achieved by the synergistic coculture grown on 3% molasses at 40 °C, pH 7, and an inoculum size of 25% (v/v). This study revealed the economic feasibility of the synergistic effects of coculture on waste management and biohydrogen production technology.

Modern Technologies of Hydrogen Production

Transitioning to energy-saving and renewable energy sources is impossible without accelerated development of hydrogen energy and hydrogen technologies. This review summarizes the state-of-the-art and recent advances of various hydrogen production processes, including but not limited to thermochemical and electrolytic processes. Their opportunities and limitations, operating conditions, and catalysts are discussed. Nowadays, most hydrogen is still produced by steam reforming of methane, its partial oxidation, or coal gasification. Considerable attention is also paid to natural gas pyrolysis. However, hydrogen produced using these technologies has a lot of impurities and needs additional purification. A series of technologies for hydrogen purification, including its filtration through palladium alloy membranes, and membrane catalysis, allowing hydrogen production and purification in one stage, are discussed. The main way to produce carbon-free hydrogen is water electrolysis using low-cost energy from nuclear or renewable sources. Both conventional and novel methods of hydrogen storage and transportation, which are an important part of the hydrogen economy, are reviewed. Biohydrogen production technologies are also discussed. Finally, prospects for further work in this field are provided. This review will be useful to researchers and manufacturers working in this field.

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.

Thermophilic biohydrogen production strategy using agro industrial wastes: Current update, challenges, and sustainable solutions

Continuously increasing wastes management issues and the high demand of fuels to fulfill the current societal requirements is not satisfactory. In addition, severe environmental pollution caused by generated wastes and the massive consumption of fossil fuels are the main causes of global warming. In this scenario, production of hydrogen from organic wastes is a potential and one of the most feasible alternatives to resolve these issues. However, sensitivity of H2 production at higher temperature and lack of potential substrates are the main issues which are strongly associated with such kinds of biofuels. Therefore, the present review is targeted towards the evaluation and enhancement of thermophilic biohydrogen production using organic, cellulosic wastes as promising bioresources. This review discusses about the current status, development in the area of thermophilic biohydrogen production wherein organic wastes as key substrate are being employed. The combinations of suitable organic and cellulose rich substrates, thermo-tolerant microbes, high enzymes stability may support to enhance the biohydrogen production, significantly. Further, various factors which may significantly contribute to enhance biohydrogen production have been discussed thoroughly in reference to the thermophilic biohydrogen production technology. Additionally, existing obstacles such as unfavorable thermophilic biohydrogen pathways, inefficiency of thermophilic microbiomes, genetic modifications, enzymes stability have been discussed in context to the possible limitations of thermophilic biohydrogen production strategy. Structural and functional microbiome analysis, fermentation pathway modifications via genetic engineering and the application of nanotechnology to enhance the thermophilic biohydrogen production have been discussed as the future prospective.

Comparative techno-economic modelling of large-scale thermochemical biohydrogen production technologies to fuel public buses: A case study of West Midlands region of England

This work presents techno-economic modelling of four thermochemical technologies that could produce over 22,000 tonnes/year of hydrogen from biomass for >2000 public transport buses in West Midlands region, UK. These included fluidised bed (FB) gasification, fast pyrolysis-FB gasification, fast pyrolysis-steam reforming, and steam reforming of biogas from anaerobic digestion (AD). Each plant was modelled on ASPEN plus with and without carbon capture and storage (CCS), and their process flow diagrams, mass and energy balances used for economic modelling. Payback periods ranged from 5.10 to 7.18 years. For operations with CCS, in which the captured CO2 was sold, FB gasification gave the lowest minimum hydrogen selling price of $3.40/kg. This was followed by AD-biogas reforming ($4.20/kg), while pyrolysis-gasification and pyrolysis-reforming gave $4.83/kg and $7.30/kg, respectively. Hydrogen selling prices were sensitive to raw material costs and internal rates of return, while revenue from selling CO2 was very important to make biohydrogen production cost competitive. FB gasification and AD-biogas reforming with CCS could deliver hydrogen at less than or around $4/kg when CO2 was sold at above $75/tonne. This study showed that thermochemical technologies could produce biohydrogen at competitive prices to extend the current use of electrolytic hydrogen-fuelled buses in Birmingham to the wider West Midlands region.

Effects of enzymatic hydrolysis and alkalization pretreatment on biohydrogen production by chlorella photosynthesis

The effects of alkalization pretreatment and enzymolysis on biohydrogen production with Chlorella vulgaris microalgae biomass by photosynthesis were studied, the alkalization pretreatment enzymolysis was to alkalize biomass raw materials before enzymolysis, the biohydrogen production kinetics equation of microalgae biomass was put forward by comparing the biohydrogen process of enzymatic hydrolysis with that of alkaline pretreatment enzymatic hydrolysis. The experimental results show: the optimum initial substrate concentration for biohydrogen production by enzymatic hydrolysis and alkaline pretreatment was 24 g/L, the maximum biohydrogen was 132.1 mL and 294.5 mL, the maximum specific biohydrogen production was 22.0 mL/g and 49.1 mL/g, and the maximum biohydrogen content was 43.9% and 56.8%. The effect of biohydrogen production by enzymatic hydrolysis after alkaline pretreatment of microalgae biomass is obviously better than that by direct enzymatic hydrolysis, which provides scientific reference and development of high efficiency and low cost biohydrogen production technology by photosynthesis of microalgae biomass.

An overview on progress, advances, and future outlook for biohydrogen production technology

The hydrogen (H2) economy has been recognized globally from a socio-economic, and environmental viewpoint. Hydrogen can be produced using technologies such as electrolysis, thermochemical, photoelectrochemical, and biological methods. Biological methods help in waste management and energy production simultaneously. To make the biohydrogen process economic and viable at a commercial scale there is a need to utilize renewable raw materials efficiently. Improved reactor designs and advanced genetic improvements using metabolic pathways developments are mandated to improve microbial adaptation to the harsh process conditions. Finally, this review aimed to fill the void among technical and applied research and review the current advances in genetic engineering and metabolic pathway developments to improve H2 productivity.

Microalgal Hydrogen Production in Relation to Other Biomass-Based Technologies—A Review

Hydrogen is an environmentally friendly biofuel which, if widely used, could reduce atmospheric carbon dioxide emissions. The main barrier to the widespread use of hydrogen for power generation is the lack of technologically feasible and—more importantly—cost-effective methods of production and storage. So far, hydrogen has been produced using thermochemical methods (such as gasification, pyrolysis or water electrolysis) and biological methods (most of which involve anaerobic digestion and photofermentation), with conventional fuels, waste or dedicated crop biomass used as a feedstock. Microalgae possess very high photosynthetic efficiency, can rapidly build biomass, and possess other beneficial properties, which is why they are considered to be one of the strongest contenders among biohydrogen production technologies. This review gives an account of present knowledge on microalgal hydrogen production and compares it with the other available biofuel production technologies.

Microalgae: The Future Supply House of Biohydrogen and Biogas

The non-renewable nature of fossil energy and the environmental pollution caused by its use, such as haze, make it very urgent to develop clean and efficient renewable energy. By using microalgae biomass as an alternative raw material energy sources like biohydrogen, methane can be produced through fermentation and photosynthesis. Unlike solar energy, which has the disadvantages of low energy density, instability and difficulty in storage, biohydrogen and biogas are one of the novel ideal energy sources at present. The utilization of microalgae has various attractive prospects in their production due to its cost-effectiveness, renewable biomass and ease of scaling-up technology. This paper discusses the latest microalgae biomass biohydrogen and biogas production technology including integrated biorefinery systems, co-production or mixed production techniques and puts forward the key problems to be solved in the development of microalgae biohydrogen production technology.

Comparative Techno-Economic Modelling of Large-Scale Thermochemical Biohydrogen Production Technologies to Fuel Public Buses: A Case Study of West Midlands Region of England

This work presents techno-economic modelling of four thermochemical technologies that could produce nearly 20,500 tonnes of hydrogen per year from biomass for public bus transport. These included fluidised bed (FB) steam gasification, fast pyrolysis-FB gasification, fast pyrolysis-steam reforming, and steam reforming of biogas from anaerobic digestion (AD). Each plant was modelled on ASPEN plus with and without carbon capture and storage (CCS), and their process flow diagrams, mass and energy balances used for economic modelling. Payback periods ranged from 6.7 to 7 years. For operations with CCS, in which the captured CO 2 was sold, FB gasification gave the lowest minimum hydrogen selling price of $2.84/kg. This was followed by AD-biogas reforming ($3.67/kg), while pyrolysis-reforming and pyrolysis-gasification giving $6.58/kg and $7.49/kg, respectively. Hydrogen selling prices were sensitive to raw material costs and internal rates of return, while revenue from selling CO 2 was very important to make biohydrogen production cost competitive. FB gasification and AD-biogas reforming with CCS could deliver hydrogen at less than $4/kg when CO 2 was sold at above $75/tonne. This study showed that thermochemical technologies could produce cheaper biohydrogen to extend the current use of electrolytic hydrogen-fuelled buses in Birmingham to the wider West Midlands region.

A Nickel- and Cerium-Doped Zeolite Composite: An Affordable Cathode Material for Biohydrogen Production in Microbial Electrolysis Cells.

Microbial electrolysis cells (MECs) is one of the promising biohydrogen production technologies for which low-cost cathode materials are required and developed to propel the rapid development of MECs. Herein, the preparation of a low-cost Ce0.1 -Ni-Y composite is reported by using Y zeolite as carrier loaded with nickel (Ni) and cerium (Ce) as active components and its prominent electrochemical performance. The XPS analysis reveals that strong electronic interaction between Ni and Ce makes a great contribution to the electrochemical performance enhancement. The Ce0.1 -Ni-Y with a peak current density of 39.8 A⋅m-2 in LSV, Tafel slope of 40.81 mV⋅dec-1 , ECSA of 34.3 and hydrogen yield of 0.312±0.013 m3 ⋅m-3 d-1 are significantly superior to that of its parent Ni-Y counterpart and rival the performance of commercially Pt/C, which renders it a very promising hydrogen evolution catalyst for MECs.

Modifying crystallinity, and thermo-optical characteristics of Paulownia biomass through ultrafine grinding and evaluation of biohydrogen production potential

Exploring the clean and low cost biohydrogen production technology with vastly spread forestry based biomass highlights the practical large scale biohydrogen production prospective. In the present work we exploited the role of ultrafine pretreatment to Paulownia biomass as a sole carbon source to evaluate biohydrogen production potential. The altered physical, thermal and optical characteristics of Paulownia biomass after pretreatment of ultrafine grinding were compared with well-studied biomass of corn stover. Microstructural, FTIR and TGA analysis highlight the deterioration of crystal structure and lignin breaking of cellulose with increase in pretreatment time, which significantly improves hydrolysis and enhances hydrogen production subsequently. In comparison to raw materials, Paulownia leaves have the highest hydrogen production potential whereas after pretreatment, total hydrogen yield from Paulownia stems is increased by 51.8% which is comparable to corn stover. Our results highlight that in comparison to conventional agriculture stover, lignocellulosic Paulownia biomass can be potential candidate for clean energy production with prospective of sustainable supply.

Green technology for sustainable biohydrogen production (waste to energy): A review

Perceiving and detecting a sustainable source of energy is very critical issue for current modern society. Hydrogen on combustion releases energy and water as a byproduct and has been considered as an environmental pollution free energy carrier. From the last decade, most of the researchers have recommended hydrogen as one of the cleanest fuels and its demand is rising ever since. Hydrogen having the highest energy density is more advantageous than any other fuel. Hydrogen obtained from the fossil fuels produces carbon dioxide as a byproduct and creates environment negative effect. Therefore, biohydrogen production from green algae and cyanobacteria is an attractive option that generates a benign renewable energy carrier. Microalgal feedstocks show a high potential for the generation of fuel such as biohydrogen, bioethanol and biodiesel. This article has reviewed the different methods of biohydrogen production while also trying to find out the most economical and ecofriendly method for its production. A thorough review process has been carried out to study the methods, enzymes involved, factors affecting the rate of hydrogen production, dual nature of algae, challenges and commercialization potential of algal biohydrogen.

Enhancement of pH values stability and photo-fermentation biohydrogen production by phosphate buffer

ABSTRACT The main aim of this study was to investigate the effects of the initial pH values of the buffer on photo-fermentation biohydrogen production. Hydrogen production and the kinetics of it under different initial pH values were analyzed. Effects of initial pH values on reducing sugar consumption, hydrogen production rate, and byproduct production were evaluated at initial pH values of 5–7. The results showed that initial pH values of phosphate buffer had a significant effect on biohydrogen production via photo-fermentation. With the initial pH value of phosphate buffer at 6.0, the cumulative hydrogen production reached its maximum, 569.6 mL. The maximum hydrogen production rate was 23.96 mL/h at the initial pH value of 6.5. With the initial pH values at 5.0 and 7.5, the maximum hydrogen production rates were becoming lower, only 5.59 mL/h and 5.42 mL/h, respectively. And with the increase in pH values, the peak period of hydrogen production was gradually delayed, indicating that the alkaline environment had a negative effect on the ability of photosynthetic bacteria. This study revealed the influence of phosphate buffer initial pH values on the biohydrogen production via photo-fermentation and aimed to provide a scientific reference for further improving the theory and technology for biohydrogen production from biomass.