• Energy Research

Rapid climate change and forecasted damage from fossil fuel combustion, forced researchers to investigate renewable and clean energy sources for the sustainable development of societies throughout the world. Biomass-based energy is one of the most important renewable energy sources for meeting daily energy needs, which are gaining in popularity daily. Gasification-based bioenergy production is an effective way to replace fossil fuels and reduce CO2 emissions. Even though biomass gasification has been studied extensively, there is still much opportunity for improvement in terms of high-quality syngas generation (high H2/CO ratio) and reduced tar formation. Furthermore, the presence of tar has a considerable impact on syngas quality. Downdraft gasifiers have recently shown a significant potential for producing high-quality syngas with lower tar concentrations. This article presents a comprehensive review on the advancement in biomass downdraft gasification technologies for high-quality synthesis gas. In addition, factors affecting syngas production and composition e.g., equivalency ratio, temperature, particle size, and gasification medium on synthesis gas generation are also comprehensively studied. The up-gradation and various applications of synthesis gas are also discussed in brief in this review article.

India's reliance on coal for energy has led to pollution, carbon emissions, and environmental hazards. To combat these issues, the Indian government is promoting renewable energy to enhance energy efficiency and reduce environmental impacts. By investing in solar, hydro, and wind power, India aims to minimize pollution and greenhouse gas emissions while meeting energy demands sustainably. The shift to renewable energy not only benefits the environment but also reduces energy import dependency and lowers costs. Renewable energy technologies like solar, hydro, and wind play a crucial role in power generation, offering clean alternatives derived from natural resources. The government's focus on providing 24/7 affordable electricity for all has spurred innovations in off-grid electricity generation, particularly in sun-rich regions. These advancements have attracted private sector investments, improved energy efficiency, and addressing energy shortages. India's target to install 337 GW of renewable energy capacity by 2027, with significant contributions from foreign and private sectors, underscores the country's vast renewable energy potential. Initiatives like the Electricity Act 2001 and rural electrification have enhanced energy conservation and distribution efficiency. The transition to electric vehicles and advancements in renewable energy technologies signal a promising future for India's energy sector, with opportunities for innovation, employment growth, and sustainable development. This article discusses the government's initiatives to promote renewable energy, the role of solar, hydro, and wind power in power generation, and the potential benefits of this transition for the Indian economy and environment.

, an invasive weed species, is widely available in different agro-climatic zones of India and has a huge potential in the gasification process. In the present investigation, the fuel properties of ...

Mathematical modeling is an integral part of the design to necessitate lower production costs and optimized performances. Biomass gasification is an area wherein extensive research is ongoing to ta...

Uttarakhand has the maximum potential of pine of about 20 lakh tonnes/year including reserved forests and van panchayat which makes pine needle an abundant resource. The analysis of the pine needles reveals it a potential biomass feedstock for gasification to produce electricity. This manuscript deals with the combustion study of Pine needles (Pinusroxburghii) biomass using a thermogravimetric analyzer to investigate the thermal degradation behavior and kinetic parameters. The pine needles were heated in the presence of air at four different heating rates 5, 10, 25 and 50 °C/min, and the degradation phenomenon was studied. From the proximate and ultimate analysis of pine needles, it was observed that the biomass could be a potential feedstock for gasification. The TG-DTG curves revealed that the main decomposition was between 190 and 450 °C with the release of 80–84% volatiles. It was observed that as the heating rate increases, the maximum decomposition temperature also increases and the peak shifts to the right. The obtained thermal data were used to calculate the kinetic parameters using Kissinger–Akharia–Sunose, Ozawa-Flynn-Wall, Friedman and Kissinger. The average values obtained from the above methods are 190.74, 190.75, 199.48 and 172 kJ/mol and 2.749 × 1022, 5.13 × 1022, 4.21 × 1021 and 4.14 × 106/min, respectively. The model fitting method and Coats–Redfern method were used to determine the kinetic triplet (A, E and n). The above model-free methods and model fitting methods predicts the progress of gasification at different positions along the reactor. Considering proximate analysis and heating value, pine needles could be considered as a potential feedstock for energy production through gasification process. The estimated results help as a source to understand the thermal degradation of biomass during the gasification process and be used to design the systems.

Biodiesel is an emerging alternative fuel that is generally made from edible and non-edible oilseed crops. Jatropha curcus has a high potential for producing biodiesel, which yields 25–35% oil along with 75–65% solid byproduct, generally called a de-oiled cake. The present manuscript deals with the co-digestion of Jatropha de-oiled cake along with cattle dung (1:1 ratio) for biogas production in a floating-type biogas digester. The experimental study was carried out in a modified KVIC biogas plant of 6 cubic meter capacity for 60 days’ retention time under psychrophilic and mesophilic temperature conditions. During all the experiments, the total solid content of the slurry was maintained fixed at 10–12% by mixing 10 kg Jatropha de-oiled cake and 10 kg cattle dung with 80 kg water. The experimental results showed that the average specific biogas production of Jatropha de-oiled cake and cattle dung slurry was observed to be 0.216 m3/kg TS, 0.252 m3/kg VS and 0.287 m3/kg TS, 0.335 m3/kg VS, respectively, under the aforementioned conditions. Moreover, the biogas methane concentration was observed to be 62.33% to 69.16% under mesophilic temperature conditions compared to the psychrophilic temperature conditions, 65.21% to 69.15%, respectively. Furthermore, the average total volatile solids mass removal efficiency of feeding material in the abovementioned process was 7% higher under mesophilic temperature conditions than psychrophilic temperature conditions. Additionally, the results indicated that a total 588.8 kg of input volatile solids produced a total of 7306.56 MJ/m3 and 5177.88 MJ/m3 energy in 60 days under psychrophilic and mesophilic temperature conditions. On the basis of the results, it is concluded that Jatropha de-oiled cake may be a superior solution for improving biogas quality and composition as well as a value-added product, i.e., organic manure.

Microwave enhanced fast and efficient alcoholysis (methanolysis and ethanolysis) of non-edible oils (algal, jatropha and pongamia) is achieved using chemically activated waste egg shell derived CaO (i.e. CaO(cesp)) as heterogeneous catalyst. CaO(cesp) was extracted from waste chicken egg shell and further activated chemically by supporting transition metal oxide. The maximum conversion was achieved using 3wt% catalysts under 700W microwave irradiation and 10:1 alcohol/oil ratio in 6min. Alcoholysis using ZnO activated CaO(cesp) catalyst has shown higher reaction yields in comparison to other modified catalysts. Methanolysis has shown better biodiesel conversion in comparison to ethanolysis. The catalyst has shown longer lifetime and sustained activity after being used for four cycles. Due to more saturated fatty acid content; algal biodiesel has shown improved fuel properties in comparison to other biodiesels.

Abstract The present study is focused on conversion of non-edible Jatropha seeds biomass to biofuels i.e., liquid, solid and gaseous fuels via solar thermochemical pyrolysis process. All the three products namely; (i) bio-oil (liquid) (ii) biochar (solid) and (iii) pyrolytic gas were characterized by means of TG (Thermo-gravimetric), FTIR (Fourier transform infrared), GC–MS (Gas chromatography mass spectroscopy), proximate and ultimate analysis; and assessed their feasibility as fuel candidates. It is explored that 20% maximum bio-oil yield was obtained with the average reactor temperature of 250–320 °C. The pyrolytic zone for the biomass was identified in the range of 203–508 °C. The ultimate analysis of the bio-oil revealed that the oil is rich in carbon (58.3%) and hydrogen (8.7%) with an average chemical composition of CH1.79N0.05O0.40. Relatively lower oxygen content in the bio-oil favors for high heating value. Higher H/C ratio (1.79) and lower O/C ratio (0.4) of the bio-oil indicates its suitability as petroleum fuel for engine applications. The carbon compounds present in the bio-oil are from C7 to C28 which may represent the mixture of diesel and gasoline fuels. Finally, it is emerged from the study that all the three products are exibiting various favorable conditions to be employed as fuel candidates for different applications such as engines and boilers.

Zeolite socony mobil-5 (ZSM-5) is a common catalyst used for biomass pyrolysis. Nevertheless, the quantitative information on the catalytic behavior of ZSM-5 on biomass pyrolysis is absent so far. This study focuses on the catalytic pyrolysis phenomena and mechanisms of biomass wastes using ZSM-5 via thermogravimetric analyzer and pyrolysis-gas chromatography/mass spectrometry, with particular emphasis on catalytic level identification and aromatic hydrocarbons (AHs) formation. Two biomass wastes of sawdust and sorghum distillery residue (SDR) are investigated, while four biomass-to-catalyst ratios are considered. The analysis suggests that biomass waste pyrolysis processes can be divided into three zones, proceeding from a heat-transfer dominant zone (zone 1) to catalysis dominant zones (zones 2 and 3). The indicators of the intensity of difference (IOD), catalytic effective area, catalytic index (CI), and aromatic enhancement index are conducted to measure the catalytic effect of ZSM-5 on biomass waste pyrolysis and AHs formation. The maximum IOD occurs in zone 2, showing the highest intensity of the catalytic effect. The CI values of the two biomass wastes increase with increasing the biomass-to-catalyst ratio. However, there exists a threshold for sawdust pyrolysis, indicating a limit for the catalytic effect on sawdust. The higher the catalyst addition, the higher the AHs proportion in the vapor stream. When the biomass-to-catalyst ratio is 1/10, AHs formation is intensified significantly, especially for sawdust. Overall, the indexes conducted in the present study can provide useful measures to identify the catalytic pyrolysis dynamics and levels.