Article
Thermodynamics
Marek Balas, Pavel Milcak, Patrik Elbl, Martin Lisy, Jakub Lachman, Petr Kracik
Summary: Biogas production through anaerobic digestion is widely used in the Czech Republic. Handling the solid residue, digestate, has become increasingly important. This study confirms the feasibility of utilizing digestate as a fuel for industrial-scale fluidised-bed gasification.
Article
Energy & Fuels
Prysathryd Sarabhorn, Panawit Sitthichirachat, Chootrakul Siripaiboon, Chanoknunt Khaobang, Prachya Palay, Tanaporn Thapsamut, Haryo Wibowo, Chinnathan Areeprasert, Fabrizio Scala
Summary: This study comprehensively evaluated the gasification of wood pellets in a pilot-scale decoupling gasifier. The results showed that the decoupling gasifier had lower temperatures in all zones compared to the conventional updraft gasifier. The tar yield from the decoupling gasifier was significantly lower, but the lower heating value (LHV) of syngas was also lower than that from updraft gasification. Kinetics and thermodynamics analysis suggested that the energy requirement for wood pellet decomposition was slightly higher in the decoupling gasifier due to its higher activation energy, and the presence of CO2 in the flue gas atmosphere caused more heavy volatiles and char.
Article
Thermodynamics
Antti Pitkaoja, Jouni Ritvanen
Summary: The study investigates the use of H2O staging and cooling in a circulating fluidised bed gasifier to enhance its chemical reactions and allow for direct adjustment of the gasifier's operating parameters, increasing flexibility in tailoring the composition of the producer gas.
Article
Energy & Fuels
Jordan Amaro, Diego Jhovanny Marinos Rosado, Andres Z. Mendiburu, Leila Ribeiro dos Santos, Joao A. de Carvalho
Summary: This work developed a predictive model for syngas composition from biomass gasification in fixed bed gasifiers, which showed better estimates compared to experimental results and other models.
Article
Energy & Fuels
Hamid Rashidi, Aidan Duffy, Wayne Doherty
Summary: This study proposed a semi-kinetic model of biomass gasification and introduced a numerical procedure to estimate the yields and compositions of char and tar. The simulation results were validated against experimental data, demonstrating the accuracy and robustness of the model for analyzing similar technologies or developing new ones.
BIOMASS CONVERSION AND BIOREFINERY
(2022)
Article
Chemistry, Physical
Ozgun Tezer, Nazlican Karabag, M. Utku Ozturk, Atakan Ongen, Azize Ayol
Summary: This study investigates the gasification potential of municipal green waste using different fixed-bed gasifier configurations. The results show that the updraft reactor system is more suitable for producing high hydrogen content. The findings are important for determining and optimizing gasification process parameters.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Energy & Fuels
Marco Mancini, Andreas Schwabauer
Summary: In recent years, gasification has gained attention as both an industrial application and a research topic. This article investigates the thermal structure of a counter-current reactor and demonstrates the significant influence of temperature on oxidation and pyrolysis regions. A non-dimensional set of equations is solved numerically using the method of lines, and four thermal structures are identified. Two stable operation positions are determined, one in the upper and one in the lower part of the reactor, and conditions for their existence and stability are discussed based on non-dimensional parameters. The findings from this analysis are applied to biomass and waste gasification configurations.
Article
Mining & Mineral Processing
Tao Xu, Yongping Wu, Sankar Bhattacharya
Summary: The gasification kinetic modelling and prediction model for Victorian brown coal chars were found to be applicable in this study, with limited effect on gasification rate by particle size under 106μm. Maddingley char and Yallourn char showed differences in activation energies and pre-exponential factors during CO2 gasification.
INTERNATIONAL JOURNAL OF MINING SCIENCE AND TECHNOLOGY
(2021)
Article
Energy & Fuels
Jan Peter Schupsky, Tobias Netter, Guixuan Wu, Hartmut Spliethoff, Michael Mueller
Summary: This study introduces a new approach for determining crystal phases in slag through crystallization investigations, providing datasets for crystal morphology of various phases. The experimental results align well with industrial pilot plant slag crystal shapes, supporting their direct application to industrial settings. This validation enhances existing viscosity models for partly crystallised slags in entrained flow gasifiers.
Article
Agricultural Engineering
Ahmed M. Salem, Manosh C. Paul
Summary: This paper presents a novel study that investigates the formation and evolution of tar species in biomass gasification using a two-dimensional numerical model. The model is validated using experimental and kinetic data and demonstrates the ability to simulate producer gas production. Benzene, naphthalene, toluene, and phenol are identified as the main tar species, with benzene having the highest concentration.
BIOMASS & BIOENERGY
(2023)
Article
Engineering, Environmental
Jianjun Cai, Ronghua Zeng, Wenheng Zheng, Shubin Wang, Jie Han, Kaiqiang Li, Ming Luo, Xingying Tang
Summary: The co-gasification of RDF and biomass is an efficient technology for MSW utilization, with higher temperature and ER values promoting syngas yield. Co-gasification demonstrated synergistic enhancements in carbon conversion efficiency, gas yield, and cold gas efficiency. Positive synergy effects were observed at lower ER and higher temperatures, while negative synergy effects tended to appear at higher ER values.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2021)
Article
Engineering, Chemical
Cai Chen, Ping Li, Lei Chen, Yiran Zhang, Longge Zhang, Xuehua Yang
Summary: Water-wall entrained flow gasifiers ensure long-term safe operation by using the idea of fighting slag with slag. Wall slagging is essential for the operation of gasifiers. In this study, the gasification process of dry coal power was simulated in an entrained flow gasifier using ANSYS Fluent software. Different models were used to simulate the reaction processes and interaction between gas and particles. The simulation results showed the deposition flux of ash particles reached a maximum value of 0.32 kg/m^2s at a distance of 2.5 m below the gasification burner, with a deposition flux of 0.08 kg/m^2s at the lower slag mouth. The maximum thickness of liquid slag and total slag layers were 14.4 and 62.7 mm, respectively.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2023)
Article
Engineering, Chemical
Nicolas Torres Brauer, Marcos Navarro Salazar, Hugo de Lasa
Summary: This article proposes a new PPPM to describe bubble properties in a lab scale fluidized bed. The PPPM is based on a balance of forces and predicts bubble rise velocity as a function of the bubble axial chord. By comparing it against 46,000 bubbles, it is shown that 91% of the bubbles fall within the PPPM prediction band. This model is expected to significantly contribute to the development of large-scale biomass gasifier models.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Agricultural Engineering
Zeba Naaz, M. R. Ravi, Sangeeta Kohli
Summary: Modelling of a downdraft biomass gasifier involves complex phenomena such as different time scales, inconsistencies in kinetic data, uncertainties in specific surface area, etc. Challenges in transient modelling, including the lack of discussion on ignition methods and radiation modelling, have not been fully addressed.
BIOMASS & BIOENERGY
(2022)
Article
Chemistry, Physical
Mehmet Utku Ozturk, Azize Ayol, Ozgun Tezer
Summary: Biomass gasification is an important renewable energy option for addressing environmental issues caused by fossil fuels and climate change. This study assessed the environmental impacts of olive pomace gasification for electricity generation, including the evaluation of its by-products biochar and tar. The analysis results show that the scenarios have very low impact values, particularly when biochar is beneficially used in different industries.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Review
Chemistry, Multidisciplinary
Dipesh Shikchand Patle, Ashutosh Pandey, Sameer Srivastava, Ashish N. Sawarkar, Sushil Kumar
Summary: This article reviews the techniques of conventional and in situ biodiesel synthesis from microalgae, with a focus on ultrasound-assisted biodiesel production. The study found that biodiesel production through ultrasonication assisted in situ processing of wet microalgae is at least three times more expensive than biodiesel production through conventional mechanisms from feedstocks such as waste cooking oil. The feasibility of ultrasound-intensified biodiesel production from microalgae is discussed.
ENVIRONMENTAL CHEMISTRY LETTERS
(2021)
Article
Engineering, Chemical
Savyasachi Shrikhande, Gunavant Deshpande, Ashish N. Sawarkar, Z. Ahmad, Dipesh S. Patle
Summary: This study presents new processes for biodiesel production using wet microalgal feedstock, ionic liquid catalyst, and ultrasonication. Retrofitting with DWC and MVR led to significant cost savings in various aspects. The study highlights the importance of experimental design and economic analysis for improving biodiesel production processes.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2021)
Article
Environmental Sciences
Rajnish Kumar Singh, Trilok Patil, Deeksha Pandey, Shyam P. Tekade, Ashish N. Sawarkar
Summary: This study investigated the kinetics and thermodynamics of co-pyrolysis of petroleum coke and banana leaves biomass, revealing synergistic effects and determining activation energy and frequency factor. Thermodynamic parameters were also calculated to evaluate the feasibility and reactivity of the co-pyrolysis process, which could be valuable for the design of co-pyrolysis systems.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2022)
Article
Energy & Fuels
Ashish N. Sawarkar
Summary: This study investigated the coke forming propensities and kinetics of upgrading Arabian mix asphalt (AMA), finding that coke formation increases with temperature but slightly decreases at 475 degrees C after 60 minutes. The liquid product yield from AMA was significantly lower than that from Arabian mix vacuum residue (AMVR), while the coke yield from AMA was approximately 1.25 times higher than that from AMVR. The activation energy for the pathway involving petroleum coke formation from AMA was 257.94 kJ/mol, slightly lower than that of AMVR which was 262.12 kJ/mol.
PETROLEUM SCIENCE AND TECHNOLOGY
(2022)
Article
Agricultural Engineering
Nikhil Kirti, Shyam P. Tekade, Ankita Tagade, Ashish N. Sawarkar
Summary: This study investigated the pyrolysis potential of pigeon pea stalk (PPS) through thermogravimetric experiments and evaluated the activation energy and enthalpy. Thermodynamic parameters and reaction mechanisms were also analyzed.
BIORESOURCE TECHNOLOGY
(2022)
Article
Engineering, Chemical
Gunavant Deshpande, Savyasachi Shrikhande, Ashish N. Sawarkar, Dipesh S. Patle
Summary: The current study focuses on the multiobjective optimization of an ultrasound intensified and ionic liquid catalyzed in situ transesterification of wet microalgae for renewable biodiesel production. The process is developed and simulated in Aspen Plus V10 simulator and an excel based multiobjective optimization (EMOO) programme for the elitist non-dominated sorting genetic algorithm-II is used for optimization. Total Annual Cost, organic waste, individual risk, and CO2 emission are chosen as the objectives for the constrained optimization of this process. The results show that the TAC reduces with the increase in the generation of organic waste, CO2 emission and IR. This article contemplates and articulates the reasons for the obtained trade-offs between objectives. The quantitative trade-offs between objectives aid to the better decision making about the process design and operation while satisfying economic, environmental and safety concerns. Finally, net flow method (NFM) has been implemented for the identification of best suitable solution in the Pareto-optimal fronts. Simultaneous optimization of all four objectives resulted in the impressive savings in TAC, organic waste, IR, and CO2 emission.
CHEMICAL ENGINEERING RESEARCH & DESIGN
(2022)
Article
Engineering, Environmental
Gunavant Deshpande, Savyasachi Shrikhande, Dipesh S. Patle, Ashish N. Sawarkar
Summary: The present study focuses on the multiobjective optimization of retrofitted in situ algal biodiesel process. By intensifying the transesterification of algal lipids with ultrasonication and catalyzing with an ionic liquid catalyst, and retrofitting conventional distillation columns into a dividing wall column, the energy consumption and CO2 emission of the process are significantly reduced. The multiobjective optimization results in a substantial decrease in cost, environmental impact, and safety risk.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2022)
Article
Agricultural Engineering
Sanjay Singh, Ankita Tagade, Ashish Verma, Ajay Sharma, Shyam P. Tekade, Ashish N. Sawarkar
Summary: This study investigated the co-pyrolysis of wheat straw and polyethylene using thermogravimetric experiments. The results showed that the maximum decomposition temperature ranges and kinetic parameters differed for the two materials. First-order reaction kinetics and diffusion models were found to dominate the co-pyrolysis process. Thermodynamic analysis confirmed the feasibility of the co-pyrolysis.
BIORESOURCE TECHNOLOGY
(2022)
Article
Agricultural Engineering
Pawan Kumar, Vishwajeet P. Singh, Ankita Tagade, Ashish N. Sawarkar
Summary: This study comprehensively characterized vetiver root (VR) and vetiver shoot (VS) after phytoremediation of heavy metal-contaminated soil. Physico-chemical properties, thermal degradation behavior, functional groups, and surface morphology were determined through various analyses. VR and VS had significantly high cellulose and hemicellulose contents and showed potential for producing pyro-gas and biochar. VR had higher inorganic matter content than VS. FESEM analysis showed that both VR and VS had porous structures with a large surface area. The thermal decomposition of VR and VS followed reaction-order and diffusion mechanisms.
INDUSTRIAL CROPS AND PRODUCTS
(2023)
Article
Energy & Fuels
Ajay Sharma, Bhupendra Suryawanshi, Bikash Mohanty, Ashish N. Sawarkar
Summary: In this research, artificial neural network (ANN) and response surface methodology (RSM) were used to predict the extraction yield (EY) of bio-oil from Mangifera indica wood (MIW) sawdust. The optimized ANN-FFBP and RSM-CCD models were developed, with the ANN-FFBP model showing superior performance. The analysis of the bio-oil revealed the presence of valuable compounds, and various techniques confirmed the commercial significance of the extracted pyrolysis products. Techno-economic assessment indicated a profitable margin for bio-oil production at an industrial scale of 10 TPD.
Review
Agricultural Engineering
Ankita Tagade, Ashish N. Sawarkar
Summary: Recently, millets have gained increasing attention due to their outstanding agronomic traits, nutritional significance, and focus on promoting their health benefits. This has resulted in cultivation of various millet varieties worldwide, generating a significant amount of millet agro-residues. This study critically analyzes previous investigations on the pyrolysis of different millet agro-residues, including physico-chemical characterization, kinetics and thermodynamic parameters, reactors used, and the relationship between reaction conditions and characteristics of millet-derived biochar and potential applications. Specific research gaps are identified based on the analysis, and future directions for harnessing the energy potential of millet agro-residues are discussed. This analysis is expected to be useful for researchers in further exploring the sustainable utilization of millet agro-residues in conjunction with other commonly used agro-residues.
BIORESOURCE TECHNOLOGY
(2023)
Article
Green & Sustainable Science & Technology
Ajay Sharma, A. Aravind Kumar, Bikash Mohanty, Ashish N. Sawarkar
Summary: In this study, the physico-chemical characterization, pyrolysis kinetics, and thermodynamic analysis of poplar wood, eucalyptus wood, and their binary blend were investigated using TGAthermograms obtained at different heating rates. The kinetic parameters were determined using model-fitting and model-free methods, which resulted in different sets of values. The endothermicity, stability, and energy barrier were found to be different for the different materials. The behavior of the pyrolysis reaction was established using the Criado method.
Article
Engineering, Environmental
S. R. Geed, A. N. Sawarkar, R. S. Singh, B. N. Rai
Summary: This study focuses on bioremediation strategies for degrading Malathion by isolating potential microbes, enhancing degradation rate in batch packed bed bioreactor, confirming metabolites, and conducting proteomics analysis. It was found that Bacillus sp. S4 is more effective than Bacillus sp. S1 and Bacillus sp. S2 in bioremediation of Malathion. The maximum removal efficiency of Malathion (72%) was achieved in a free cell and further improved to 84% in a batch packed bed bioreactor at optimum pH (7.5) and temperature (32 degrees C). Two metabolites, Malathion monocarboxylic acid and Succinic acid, were identified. Growth kinetics and inhibition kinetics were evaluated, and proteins were characterized through sequential, functional, and structural analysis. The findings are expected to contribute to the practical application of Bacillus sp. S4 in removing Malathion from contaminated environments.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2022)
Article
Engineering, Chemical
Achyut Pakhare, Channamallikarjun Mathpati, Vishwanath H. Dalvi, Jyeshtharaj Joshi, Raosaheb Patil, Ekambara Kalekudithi
Summary: The crystal characteristics of ibuprofen are influenced by various design and operating parameters, such as impeller design, speed, seed size and quantity, and cooling profiles. Proper adjustment of these parameters can improve the flow properties and crystal size of ibuprofen, and closed clear impellers show better performance.
INDIAN CHEMICAL ENGINEER
(2022)
Article
Engineering, Chemical
Sanjay Singh, Ashish N. Sawarkar
Summary: The study focuses on the bioenergy potential of corn cob, analyzing its physico-chemical characteristics, thermal degradation behavior, and pyrolysis kinetics. Results suggest significant content of cellulose and hemicellulose in corn cob, indicating its high yield potential for bio-oil production through pyrolysis. The activation energy for pyrolysis of corn cob, determined using isoconversional methods, was found to be in close proximity, highlighting the prospective bioenergy potential of corn cob as a feedstock for the pyrolysis process.
CHEMICAL PRODUCT AND PROCESS MODELING
(2021)
