Hydrogen and ethanol derived from lignocellulosic biomass are promising biofuels and have great potential to become alternatives to fossil fuels. The current research focuses on the carbohydrate platform for simultaneous production of ethanol and hydrogen in fluidized bed and stirred tank bioreactor. The Taguchi method of optimization was applied to optimize both the pretreatment processes. The ultrasound assisted lime pretreatment process was found to be superior to dilute acid pretreatment process and it removed 68%, 65% and 64% of the lignin present in the naïve lignocellulosic fibers of Bonbogori, Areca nut peel and Moj, respectively. The saccharification process was carried out for 96 hours at 50°C, 150 RPM and the saccharification efficiency (ultrasound assisted lime pretreatment) was highest in Bonbogori (82.5%), followed by Moj (80.1%) and Arecanut peel. (79.5%).Among all the three biomass used in this study, Bon bogori showed the maximum desiccation efficiency, therefore Bonbogori was used for the fermentative production of both ethanol and hydrogen. Immobilized sewage sludge was used for simultaneous bioethanol and hydrogen production from the enzymatic hydrolyzate of Bonbogori. The optimum factor combination for both ethanol and hydrogen production was achieved at 40°C temperature and 5.5 pH. Fluidized bed bioreactor outperformed the stirred tank reactor for the production of both ethanol mol) and hydrogen mmol).
List of Tables
Nomenclatures
SSCF Simultaneous saccharification and co-fermentation SSF Simultaneous saccharification and fermentation STR Stirred tank reactor.
Summary
Based on the above brief discussion, it thus appears that there is enough room for research into the simultaneous production of ethanol and hydrogen from lignocellulosic biomass materials. To obtain lignin less pure fractions of cellulose and hemicellulose from effective pretreatment of lignocellulosic biomass for optimal yield of hydrogen and ethanol.
Introduction
Physico-chemical Characteristics of Lignocellulosic Biomass
The caloric values of all biomasses were in the range from 17 MJ kg-1 to 22 MJ kg-1.
Pretreatment of LignocellulosicBiomass
Optimum conditions for Moj and Bonbogri were observed at lime loading ratio of 0.75, biomass loading ratio of 20 and ultrasonic irradiation duration of 120 minutes, but for Arecanut shell the ultrasonic irradiation duration was 180 minutes.
Saccharification of Biomass
Characterization of Wastewater Sludge
The optimal combination of factors for the production of ethanol and hydrogen was achieved at a temperature of 40 °C, an OLR of 50 kg L-1 and a pH of 5.5. The fluidized bed bioreactor showed better performance than the stirred tank bioreactor for the simultaneous production of ethanol and hydrogen.
Conclusions and future work
This chapter describes the simultaneous production of hydrogen and ethanol using Bonbogori pre-treated sonicated saccharified lime. Under these designed conditions, the optimal yield of ethanol and biohydrogen was found to be 0.21 mol and 30.8 ± 0.5 mmol, respectively.
Introduction
Introduction
World oil demand will increase to 14748 million barrels of oil equivalent by 2020, but world reserves of natural gas are about 1.41 m3; the gross production of gas is approximately 2.41 m3 per year [3]. Energy security is an indispensable feature of a country's independence and livelihood. The results of Figure 1.1 clearly show that 80% of the energy used by humans is not sustainable.
International Scenario of Biofuel
A regional breakdown of the energy potential of different biomass materials (Table 1.2) showed that the potential of energy generation from biomass materials is fairly evenly distributed across the different continents. The total energy generation potential, regardless of biomass types, is about 20,000 PJa-1, of which Asia's contribution is about 40% of the world's total potential.
![Table 1.1 Scenario of usage renewable energy resources [6]](https://thumb-ap.123doks.com/thumbv2/azpdfnet/10344797.0/30.918.169.838.161.1022/table-scenario-usage-renewable-energy-resources.webp)
Indian Scenario of Biofuel
Biofuel production in India can also be seen as an option for generating rural employment and promoting rural development. From the available data it can be concluded (Table 1.3) that although the production rate of biofuels is quite high, but the quantity of biofuel production in India is not up to par compared to the rest of the world.
Overview of biofuel resources and environmental issues
Fourth generation biofuels are based on the conversion of vegetable oils and biodiesel into biogasoline using algae using the most advanced technologies [26]. TGB is about the processing of algal biomass for the production of biofuels, while the Challenges that remain in the bioconversion process include recalcification of the lignocellulosic matrix. The series of enzymatic reactions are observed during the hydrolysis of both cellulose and hemicellulosic material to yield both five- and six-carbon sugars [40].
Pathways of bioethanol and biohydrogen production
Therefore, the first challenge is the pretreatment of lignocellulosic biomass to reduce biomass recalcitrance, to improve the yield of fermentable sugars. This study emphasizes dilute acid pretreatment and ultrasound-assisted lime pretreatment of lignocellulosic biomass materials.
Scopes of current research and objectives
In contrast, fluidized bed reactors are supposed to address these limitations with the goal of addressing simultaneous production of both hydrogen and ethanol. To obtain lignin less pure fractions of cellulose and hemicellulose from efficient pretreatment of lignocellulosic biomass for higher yield of hydrogen and ethanol.
Chapter -II Physico-chemical Characterization of
Introductionand review of literature
The Arecanut husk is known as a residue of agricultural waste in Northeast India. dye and leather industries [5]. Areca is a genus of about 50 species of single trunk palms in the family Arecaceae, found in humid tropical forests. The known member of the genus is A. Local tribes and villagers traditionally prefer it as firewood. The major advantage of using such biomass is its availability and there will be no upheaval for biorefinery collection and formation.
Materials and methods
- Physical and chemical characterization of biomass .1 CHNSO analysis
For estimation of extractions in the biomass samples NREL protocol was used [24]. The biomass samples (5 gm) were extracted using soxhlet extraction apparatus through extraction thimbles (single thickness, cotton cellulose thimble with external length 94 mm and ID 33 mm). The hemicellulose and cellulose part of biomass usually starts to decompose at about 206 °C and 315 °C and decomposition of lignin starts to decompose above 330 °C, respectively [26]. The thermal decomposition study carried out on rapeseed (Brassica napus L), sponge ground fibers, sugarcane bagasse banana fibers by several researchers revealed that the thermal decomposition of hemicellulose occurred at temperatures ranging from 150 °C to 350 °C, cellulose was decomposed at temperature range of 275.
Results and discussion
The maximum crystallinity was observed in Areca nut shell fiber (63.84%) followed by Moj (46.43%) and Bonbogori (42.46%) (Fig. 2.6). The results showed that Areca nut shells are less prone to enzymatic digestion than other two biomasses. materials. An ideal biomass for bioenergy production should have high calorific value along with high cellulose and hemicellulose concentration than lignin and ash content. The physicochemical characterization of all three biomass samples showed that Bonbogori and Moj both have almost the same calorific value and structural sugar (cellulose and hemicellulose), but Moj is more feasible than Bonbogori due to its high cellulose and relatively lower lignin content.
Conclusions
The study of all these biomasses from North East India ensures that these biomasses can be used as feedstock regardless of the biofuel production process route such as gasification or fermentation to meet the second generation biofuels requirements. Rapid analysis of the chemical composition of agricultural fibers using near-infrared spectroscopy and pyrolysis molecular beam mass spectrometry.
Chapter-III Pretreatment of Lignocellulosic Biomass
Introductionand review of literature
Among all the pretreatment processes, the chemical pretreatment process has a fast and good recovery of sugar after enzymatic hydrolysis. In addition to irradiation, other physical pretreatment processes require a large energy input for the pretreatment process to be successful.
Dilute acid pretreatment process
Noureddiniet al. (2010) studied distillers grains and corn fiber as biomass for a pretreatment process. The total carbohydrate content of distiller's grain and corn fiber was, respectively, wt%. The total amount of dissolved matter during hydrolysis was significantly higher than the amount of monomeric sugars. 2012) investigated straw and rice straw pretreatment with dilute sulfuric acid and enzymatic hydrolysis of cellulose [29].
Ultrasound assisted lime pretreatment
Alkaline pretreatments successfully increase the digestibility of lignocellulose without the production of furfural and methyl furfural [37]. Alkaline material reacts with biomass in three ways, namely 1. This reaction will proceed and produce phenolic hydroxyl groups from aryl-alkyl cleavage. -the boundaries of the ether.
Materials and methods
Based on the Taguchi method, an orthogonal array experiment (L9) was designed to determine the optimal conditions for the dilute acid and lime pretreatment method. The experiments were designed with three factors at three different levels viz. The delinification index was used as a response to ultrasound-assisted lime pretreatment. After each set of experiments (ultrasonic assisted lime pretreatment) samples were collected and analyzed for lignin content. The lignin content of the pretreated biomass material was measured by using the NREL protocol.
Results and discussion
Based on the result (Table 3.5) the S/N ratio of each parameter was calculated at each level as illustrated in (Fig. 3.5 and Fig. 3.6). The results (Table 3.10) showed that the ultrasound-assisted lime pretreatment process increases lime consumption regardless of the type of biomass species.
Conclusions
Delignification selectivity and kinetics for oxidative short-term pretreatment of poplar wood with lime, Part I: Constant pressure. 55] Taherzadeh MJ, Karimi K., Pretreatment of lignocellulosic waste to improve ethanol and biogas production: A review, Int.
Saccharification of pretreated biomass
- Introduction
- Mechanism of enzymatic hydrolysis
- Materials and method
- Results and discussion
- Conclusions
They are present in 13 of the 82-glycoside hydrolase families identified by sequence analysis [3]. The lists of microorganisms that produce cellulase are listed below in Table 4.1. The enzyme was well reported with hydrolysis of lignocellulosic biomass such as aspen, switch grass [7], sweet sorghum, bagasse [8], corn stover [9], fiber sludge [10], sugar cane bagasse [11]. The present study was conducted using Accelerase®1500 for saccharification and this enzyme was donated by Genencore International, B.V.
Characterization of Wastewater Sludge
- Introduction
- Materials and Method .1Wastewater sludge
- Sedimentation
- Proximate analysis
- Total Solids
- Volatile and Fixed Solids
- Total Nitrogen
- Biological Oxygen Demand (BOD)
- Chemical Oxygen Demand (COD)
- Thermal analyses
- Microbiological analysis
- FTIR analysis
- Results and discussion
- Conclusion
There are two recognized methods for measuring BOD, namely the dilution method and the manometric respirometric method. It was found to be about 3% of the total vol. The specific gravity of the sewage sludge was determined to be 1.04 and the total solids concentration was 17.8%.
Simultaneous Ethanol and Hydrogen
Introduction and literature review
- Bio-ethanol
- Photolysis
- Simultaneous ethanol and hydrogen production
Therefore, the aim of this work is the simultaneous production of bioethanol and biohydrogen and the exploration of integration as an important way to improve the process in the production of this liquid biofuel. However, pH values lower than 4.5 are favorable for the production of H2, CO2, acetic acid, butyric acid and ethanol [40].
Materials and Method
- Preparation of Substrate for Fermentation
- Bioreactors
- Immobilization of Sludge and Media Preparation
- Fermentation
- Analytical Methods
The broth was fed thoroughly from the bottom of the reactor along with the nitrogen gas to create the anaerobic condition. The broth was thoroughly fed from the top of the reactor together with the nitrogen gas to create the anaerobic condition.
Results and Discussion
The data showed that the effect of factor B for the co-production of ethanol and hydrogen was greater (41.18%), followed by A, D and C. Fluidized bed bioreactor outperformed the stirred tank reactor for the production of both ethanol and hydrogen.
Conclusions
Hydrogen production and substrate consumption characteristics of Rhodopseudomonas palustris CQK01 in a photobioreactor with immobilized cells. Biofuel production from sweet sorghum: fermentation hydrogen production and anaerobic digestion of residual biomass.
Conclusions and Future Scope
Conclusions
Similarly, both lime and ultrasound-assisted lime pretreatment reports on the removal of lignin varied between 64% and 68% present in the native lignocellulosic fiber of studied biomass, i.e. this research work could also be one of the interesting directions for mixed culture systems in the future.
Appendix -A
Taguchi methodology
A better way to compare the population behavior is to use the mean square deviation (MSD) of the results. The overall desirability can be defined as the geometric mean of the individual desirability (Eq. A-6).
Appendix-B
Error Analysis
The coefficient of determination (R2) for the calibration curves varied between 0.9891 (HPLC calibration) and 0.9994.
Research Outputs
![Table 1.2. Scenario of global bioenergy potentiality [Peta Joules per Annum (PJa -1 )][8]](https://thumb-ap.123doks.com/thumbv2/azpdfnet/10344797.0/31.918.164.816.311.775/table-scenario-global-bioenergy-potentiality-peta-joules-annum.webp)
