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Records with Subject: Process Design
Showing records 1826 to 1850 of 2307. [First] Page: 70 71 72 73 74 75 76 77 78 Last
A New Theobromine-Based EGFRWT and EGFRT790M Inhibitor and Apoptosis Inducer: Design, Semi-Synthesis, Docking, DFT, MD Simulations, and In Vitro Studies
Eslam B. Elkaeed, Reda G. Yousef, Hazem Elkady, Aisha A. Alsfouk, Dalal Z. Husein, Ibrahim M. Ibrahim, Mohamed Alswah, Heba S. A. Elzahabi, Ahmed M. Metwaly, Ibrahim H. Eissa
February 21, 2023 (v1)
Keywords: anti-proliferative, docking, EGFR inhibitors, MD simulation, theobromine
The essential pharmacophoric structural properties were applied to design a new derivative of theobromine as an antiangiogenic EGFR inhibitor. The designed candidate is a (para-nitrophenyl)acetamide derivative of the natural alkaloid, theobromine (T-2-PNPA). The potentialities of T-2-PNPA to inhibit the EGFR protein were studied computationally in an extensive way. Firstly, the molecular docking against EGFRWT and EGFRT790M demonstrated T-2-PNPA’s capabilities of binding with the targeted receptors. Then, the MD experiments (for 100 ns) illustrated through six different studies the changes that occurred in the energy as well as in the structure of EGFR−T-2-PNPA complex. Additionally, an MM-GBSA analysis determined the exact energy of binding and the essential residues. Furthermore, DFT calculations investigated the stability, reactivity, and electrostatic potential of T-2-PNPA. Finally, ADMET and toxicity studies confirmed both the safety as well as the general likeness of T-2-PNPA. Co... [more]
Optimization Design of an Alfalfa Seed Airflow Collection and Drainage System Based on Numerical Simulation
Wenpeng Ma, Shining Zhang, Chengqian Jin, Xiang Yin, Guohai Zhang, Lu Zhu
February 21, 2023 (v1)
Keywords: ADAMS, EDEM, Fluent, pneumatic, seeding device
In order to improve the working performance of an Alfalfa air conveyor, a type of horizontal screw conveyor with a seed stirring function was designed. The working process of the horizontal screw conveyor was co-simulated by EDEM software and ADAMS software. The effects of a seed stirring mechanism on population movement characteristics, population stress, the seed mass flow rate and the variation coefficient of each index were obtained. The results showed that the stirring mechanism can effectively improve the mobility of the population, reduce the local dead zone of the population, and increase the material filling coefficient between the spiral blades. Under the same working conditions, the horizontal screw conveyor with a stirring mechanism has a higher conveying efficiency and better conveying uniformity. In order to optimize the structure parameters of the Venturi injector diffuser and improve seeding efficiency and uniformity, EDEM software and Fluent software were used to co-si... [more]
Nanofiltration Treatment of Industrial Wastewater Doped with Organic Dye: A Study of Hydrodynamics and Specific Energy
Rokia Youcef, Nassila Sabba, Amel Benhadji, Hayet Djelal, Nadim Fakhfakh, Mourad Taleb Ahmed
February 21, 2023 (v1)
Keywords: Brilliant Blue FCF, dilution ratio, nanofiltration membrane processes, specific energy consumption, wastewater treatment
This study was conducted to eliminate the ions and molecules present in the industrial wastewater received by the municipal wastewater treatment plant (WWTP) of Reghaia, which is located east of Algiers, Algeria. The process was developed for two different study matrices: (a) the wastewater from WWTP and (b) wastewater mixed with Brilliant Blue FCF (BBF) dye to show the influence of the strength of the ionic solution on the treatment. The most effective operating parameters were determined by assessing the residence time distribution applied to the reactor flow regime. Energy analysis showed the viability of a nanofiltration membrane, improving the permeate flux. The nanofiltration process consumed 1.94 kWh/m3 to reduce the chemical oxygen demand (COD) of 63.58% and 48.35% for raw wastewater and doped BBF wastewater, respectively. The results demonstrated that nanofiltration performance with a volume dilution ratio of 1/2 showed the reduction of the COD of 87.2% after 15 min for undope... [more]
Biochemical Study of Bacillus stearothermophilus Immobilized Lipase for Oily Wastewater Treatment
Abir Ben Bacha, Mona Alonazi, Humidah Alanazi, Mona G. Alharbi, Raida Jallouli, Aida Karray
February 21, 2023 (v1)
Keywords: CaCO3, immobilized lipase, wastewater treatment
Traditional wastewater treatments involve expensive mechanical and physiochemical methods, so researchers have been developing cost-effective, sustainable technologies that use enzymes to produce higher quality effluents and recover more energy and nutrients from wastewater. A thermostable, alkaline, and solvent-tolerant lipase was partially purified from thermophilic Bacillus stearothermophilus. The lipase displayed maximum activity at 50 °C and pH 11.0 and catalyzed both short- and long-chain triacylglycerols at similar rates. B. stearothermophilus lipase also exhibited high stability when incubated at 40 °C for 1 h with anionic and non-ionic surfactants. Studies show that thermostable enzymes can be improved through immobilization and modification of other reaction conditions. Therefore, B. stearothermophilus lipase was immobilized through adsorption on CaCO3, Celite 545, and silica gel with the CaCO3 support producing the best adsorption rate (89.33%). The optimal initial lipase ac... [more]
Effect of Poultry Manure-Derived Compost on the Growth of eucalypts spp. Hybrid Clones
Pedro F. Rizzo, María C. Salinas, Virginia Della Torre, Juan P. Diez, Leonardo F. Sallesses, Nicolás I. Riera, Pablo S. Pathauer, Dimitrios Komilis, Antoni Sánchez
February 20, 2023 (v1)
Keywords: forest valorization, substrates, vegetative propagation
Interspecific hybrids of E. grandis × E. camaldulensis were generated to widen the plantation area. The aim of this study was to assess root capability and development for six different clones of eucalyptus grown in substrates made with three different composts derived from poultry manure. A factorial design was used to assess the effect of different composts on six growth variables. The analysis detected a greater effect from the genotype than the substrate. E. grandis × E. camaldulensis hybrid vegetative propagation was successful in alternative substrates formulated from composted poultry manure. GC8 was the genotype that showed the greatest differences for four the different variables among the substrates, being both the most sensitive and the one with the highest values for all parameters measured. The hybrids’ vegetative propagation was determined in alternative substrates formulated from poultry manure compost. The physicochemical characteristics of substrates composed of pine b... [more]
Special Issue on “Process Design and Sustainable Development”
Peter Glavič
February 17, 2023 (v1)
Thirty years ago, at the United Nations’ (UN) Earth Summit in Rio de Janeiro, Brazil, 178 countries adopted Agenda 21, a global partnership for sustainable development to improve human lives and protect the environment [...]
Incidence of Electric Field and Sulfuric Acid Concentration in Electrokinetic Remediation of Cobalt, Copper, and Nickel in Fresh Copper Mine Tailings
Rodrigo Ortiz-Soto, Daniela Leal, Claudia Gutierrez, Alvaro Aracena, Marcelo León, Andrea Lazo, Pamela Lazo, Lisbeth Ottosen, Henrik Hansen
February 17, 2023 (v1)
Keywords: electrokinetic remediation, heavy metal removal, mine tailing
In the present study, the assessment of heavy metal contaminant migration from fresh mine tailings was conducted using the electrokinetic remediation technique (EKR). In this sense, a pilot EKR cell was designed to evaluate the recovery potential of copper, nickel, and cobalt species. In particular, the focus was on the impacts of electric field intensity and pH in initial mixture and testing their interaction in copper, nickel, and cobalt migration. Experiments were made using a 22 factorial experimental design with a central point, using DC electric fields from 1.0 to 2.0 V cm−1 and H2SO4 pretreatment solutions from 1.0 to 2.0 mol L−1, along with an ANOVA test with error reduction. The metal removal rates were approximately 7% for cobalt, neglectable for copper, and 6% for nickel. In the best cases, the highest concentrations by migration at the cathodic zone were 11%, 31%, and 30%, respectively. According to ANOVA tests, factor interaction was proven for each metal in the half cell... [more]
Design and Testing of the Peanut Pod Cleaning Device
Chenhui Zhu, Bo Chen, Jiongqi Li, Yuan Liu, Liquan Yang, Wanzhang Wang, Hongmei Zhang
February 17, 2023 (v1)
Keywords: cleaning device, impurities, losses, peanut pod
Due to the design of peanut harvesters and cleaners, peanut pods are often mixed with soil, gravel, peanut straw, and other impurities. To solve this problem, this study focused on designing a peanut pod cleaning device by integrating a negative pressure centrifugal fan, a hydrometric cleaning sieve, and a reversible long-mesh cleaning sieve. The relative motion of the peanut pod on the sieve was discussed, its stress analyzed, the design parameters of the sieve and fan determined, and the operation of the device was monitored by using sensors, which accurately recorded and adjusted the working parameters. Finally, the key parameters were tested, and the results showed that the design requirements were met at a vibration frequency of 5.5 Hz, a hydrometric cleaning sieve inclination of 15°, a reciprocating long mesh cleaning sieve inclination of 5°, and a fan speed of 1500 rev/min; the mean loss is 2.26%, and the mean impurity is 3.18%. The findings can be used to provide technical supp... [more]
Special Issue “Modelling and Optimal Design of Complex Biological Systems”
Jérôme Harmand, Alain Rapaport, Neli Dimitrova, Ivan Simeonov
February 17, 2023 (v1)
At present, complex biological processes are used in many industrial areas [...]
An Integrated Method of Bayesian Optimization and D-Optimal Design for Chemical Experiment Optimization
Xinye Huang, Shuyuan Zhang, Haoran Li, Tong Qiu
February 17, 2023 (v1)
Keywords: Bayesian optimization, chemical experiment optimization, D-optimal design, experiment space exploration
The smart chemical laboratory has recently emerged as a promising trend for future chemical research, where experiment optimization is of vital importance. The traditional Bayesian optimization (BO) algorithm focuses on exploring the dependent variable space while overlooking the independent variable space. Consequently, the BO algorithm suffers from becoming stuck at local optima, which severely deteriorates the optimization performance, especially with bad-quality initial points. Herein, we propose a novel stochastic framework of Bayesian optimization with D-optimal design (BODO) by integrating BO with D-optimal design. BODO can balance the exploitation in the dependent variable space and the exploration in the independent variable space. We highlight the excellent performance of BODO even with poor initial points on the benchmark alpine2 function. Meanwhile, BODO demonstrates a better average objective function value than BO on the benchmark Summit SnAr chemical process, showing its... [more]
Analysis of the Flow Field at the Tip of an Axial Flow Compressor during Rotating Stall Process Based on the POD Method
Yueheng Wang, Moru Song, Jiali Xin, Bo Yang
February 17, 2023 (v1)
Keywords: axial flow compressor, proper orthogonal decomposition method, rotating stall, stall cell, stall mode
Rotating stalls are one of the most dangerous phenomena to be avoided in the designing and operating of axial flow compressors. An understanding of the evolution of the flow characteristics around the rotor tip region is important to study the process of stall development. In this paper, some critical characteristics of the stall-related structures, which could not be observed by the traditional analysis methods, are understood by using the proper orthogonal decomposition (POD) method. The detailed unsteady flow fields in a typical transonic axial flow compressor during the stall process are obtained by the validated numerical simulation. Thereafter, the proper orthogonal decomposition method, as a method for model reduction and decomposition, is adopted to extract the flow characteristics from the numerical results of the stall process. It is found that the flow characteristics during the stall process can be well decomposed by the POD method. The pre-stall POD results show that the i... [more]
Design and Development of a High-Speed Precision Internal Grinding Machine and the Associated Grinding Processes
Zhou Chang, Qian Jia, Lai Hu
February 17, 2023 (v1)
Keywords: high-speed grinding, hydrostatic bearings, internal grinding machine, machining dynamics, precision machine design
In order to meet the P2-grade bearing grinding requirements, we designed a high-speed internal grinding machine to be used for grinding bearing raceways and inner circles. The machine has a T-type layout and a four-axis numerical control linkage. It is supported by hydrostatic pressure and driven directly by a torque motor. In addition, it is equipped with a high-speed hydrostatic grinding wheel spindle. Our design includes a hydrostatic workpiece shaft and hydrostatic turntable, and the process has a good engineering application value. Finally, the designed precision grinding machine was used to grind a P2-grade bearing raceway.
A Simultaneous Design and Optimization Framework for the Reaction and Distillation Sections of Methanol to Olefins Process
Ning Li, Liwen Zhao, Dan Li, Huifeng Sun, Di Zhang, Guilian Liu
February 17, 2023 (v1)
Keywords: Distillation, methanol to olefins, model, Optimization, Reaction
The reaction and separation sections are the keys to the methanol-to-olefins (MTO) chemical processes, and they should be optimized to reduce the cost of production. This work develops a framework for the simultaneous design and optimization of the reaction and distillation sections. An optimization model with shortcut and rigorous methods combined is established for distillation columns to improve accuracy and efficiency. With the auxiliary devices and the selection of utilities considered, the reaction and distillation sections are integrated to maximize profits. The genetic algorithm targets the optimal parameters, including the catalyst’s coke content and reaction temperature, each column’s operating pressure, and the allocation of utilities and auxiliary devices. For the studied MTO process, the optimal reaction temperature and catalyst’s coke content were identified to be 496 °C and 7.8%, respectively. The maximum profit is 15.3% greater than that identified with only the separat... [more]
Using Particle Residence Time Distributions as an Experimental Approach for Evaluating the Performance of Different Designs for a Pilot-Scale Spray Dryer
Zelin Zhou, Timothy A. G. Langrish, Sining Cai
February 17, 2023 (v1)
Keywords: chamber design, particle residence time, spray drying, wall-deposit re-entrainment
The performances of four different designs for a pilot-scale spray dryer have been evaluated and compared based on experimentally measured particle residence time distributions (RTD), recovery rates and physical properties of spray-dried fresh skim milk. The RTDs have been measured using a dye pulse injection method, and the measurements have been fitted to models using continuous stirred-tank reactors in series (CSTR-TIS) for quantitative performance evaluation and comparison. Conical drying chambers and a box connection design have been used in the latest dryer design to reduce the amount of wall deposition and provide a smoother gas flow pattern. The particle-to-gas mean residence time ratio for the latest design is significantly closer to unity (1.6 s/s to 1.0 s/s) compared with earlier designs (2.6 s/s to 1.5 s/s). The latest design has a wider spread of RTD (n = 5−8) compared with earlier designs (n = 13−18), which may be linked to the recirculation zone in the box connection. Al... [more]
Influence of Particle Shape on Tortuosity of Non-Spherical Particle Packed Beds
Simson Julian Rodrigues, Nicole Vorhauer-Huget, Thomas Richter, Evangelos Tsotsas
February 16, 2023 (v1)
Keywords: effective thermal conductivity, packed bed, particle shape, sphericity, tortuosity, ZBS model
Tortuosity in packed beds or porous media is of significant interest in many fields, from geoscience to the chemical industry. Tortuosity plays a significant role in the mass transport in porous media, but also in their residual thermal or electric conductivity when the particles are not conducting. Several predictive models have been proposed to evaluate tortuosity, but there is still a gap when it comes to considering various particle shapes. The preponderance of tortuosity models substantiated in the literature are porosity-dependent while only a few include shape parameters. In this work, we propose a new model with sphericity and porosity to predict the tortuosity based on thermal simulations carried out with non-conducting particles for domains with no wall effect. The beds generated from rigid body simulations are compared and studied for different particle shapes with a sphericity range of 0.65−1. Sphericity showed a significant effect on the tortuosity compared with other 3D s... [more]
Integration of Gasification and Solid Oxide Fuel Cells (SOFCs) for Combined Heat and Power (CHP)
Paula Costa, Filomena Pinto, Rui Neto André, Paula Marques
October 25, 2022 (v1)
Keywords: gasification, solid oxide fuel cells (SOFC), syngas conditioning
This paper reviews the most recent information about the main operations to produce energy from carbonaceous materials, namely biomass and wastes through the integration of gasification, syngas cleaning and solid oxide fuel cells (SOFCs), which have shown to be a good option for combined heat and power (CHP) production, due to high efficiency and low environmental impact. However, some challenges still need to be overcome, mainly when mixed feedstocks with high contents of hazardous contaminants are used, thus syngas cleaning and conditioning is of major importance. Another drawback is SOFC operation, hence new materials especially for the anode has been proposed and tested. An overall process to produce CHP by gasification integration with SOFC is proposed.
Design, Modelling, and Experimental Validation of a Scalable Continuous-Flow Hydrothermal Liquefaction Pilot Plant
Ib Johannsen, Björn Kilsgaard, Viktor Milkevych, Dale Moore
October 13, 2022 (v1)
Keywords: biofuel, chemical process engineering, heat transfer, Hydrothermal Liquefaction, non-isothermal fluid flow, pilot plant, plug flow reactor, process modelling, sustainable fuel
In this study, the design and practical implementation of a novel, scalable plug-flow pilot plant for hydrothermal liquefaction of organic feedstock is presented. The overall discussion comprises the system’s design, process modelling, and simulation, as well as results for an experimental validation of the proposed design with a focus on fluid dynamics and heat transfer. The design criteria take into account the scalability of the plug-flow processing system, optimized non-isothermal flow conditions of highly viscous liquids in a tubular system at harsh process conditions, specifically high pressure and medium temperatures, and overall maintenance suitability. A novel forced flow oscillation system as well as unique heat exchange design to reduce the energy consumption during system operation, maximize local flow mixing, and minimize plugging are proposed and experimentally tested. To achieve a better understanding and optimization of Hydrothermal Liquefaction (HTL) (and other) proces... [more]
Conceptual Design of a Negative Emissions Polygeneration Plant for Multiperiod Operations Using P-Graph
Jean Pimentel, Ákos Orosz, Kathleen B. Aviso, Raymond R. Tan, Ferenc Friedler
October 13, 2022 (v1)
Keywords: carbon dioxide removal, multiperiod optimization, negative emissions technologies, power-to-x, process network synthesis
Reduction of CO2 emissions from industrial facilities is of utmost importance for sustainable development. Novel process systems with the capability to remove CO2 will be useful for carbon management in the future. It is well-known that major determinants of performance in process systems are established during the design stage. Thus, it is important to employ a systematic tool for process synthesis. This work approaches the design of polygeneration plants with negative emission technologies (NETs) by means of the graph-theoretic approach known as the P-graph framework. As a case study, a polygeneration plant is synthesized for multiperiod operations. Optimal and alternative near-optimal designs in terms of profit are identified, and the influence of network structure on CO2 emissions is assessed for five scenarios. The integration of NETs is considered during synthesis to further reduce carbon footprint. For the scenario without constraint on CO2 emissions, 200 structures with profit... [more]
Energy, Exergy, and Thermo-Economic Analysis of Renewable Energy-Driven Polygeneration Systems for Sustainable Desalination
Mohammad Hasan Khoshgoftar Manesh, Viviani Caroline Onishi
October 12, 2022 (v1)
Keywords: economic analysis, energy and exergy analysis, exergoeconomic analysis, exergoenvironmental analysis, Renewable and Sustainable Energy, sustainable development
Reliable production of freshwater and energy is vital for tackling two of the most critical issues the world is facing today: climate change and sustainable development. In this light, a comprehensive review is performed on the foremost renewable energy-driven polygeneration systems for freshwater production using thermal and membrane desalination. Thus, this review is designed to outline the latest developments on integrated polygeneration and desalination systems based on multi-stage flash (MSF), multi-effect distillation (MED), humidification-dehumidification (HDH), and reverse osmosis (RO) technologies. Special attention is paid to innovative approaches for modelling, design, simulation, and optimization to improve energy, exergy, and thermo-economic performance of decentralized polygeneration plants accounting for electricity, space heating and cooling, domestic hot water, and freshwater production, among others. Different integrated renewable energy-driven polygeneration and desa... [more]
Comparative Investigation of Different CO2 Capture Technologies for Coal to Ethylene Glycol Process
Yanqing Ma, Yitao Liao, Yi Su, Baojie Wang, Yong Yang, Dong Ji, Hongwei Li, Huairong Zhou, Dongliang Wang
October 12, 2022 (v1)
Keywords: acid gas removal, Carbon Dioxide Capture, coal to ethylene glycol, performance analysis, process simulation
The coal to ethylene glycol (CTEG) process has drawn much attention due to the serious conflict between supply and demand of ethylene glycol in China. However, it is inevitably accompanied by the problem of high CO2 emissions. Carbon capture is one of the most promising potential effective ways to address this issue. However, the CTEG process, integrated with carbon capture technology, will lead to energy and economic penalties. Thus, a comprehensive evaluation of CTEG process with different CO2 capture technologies is urgently needed. This study analyzed the technoeconomic performance of four CO2 capture alternatives for the CTEG process: Rectisol, mono-ethanol amine (MEA), chilled ammonia process (CAP) and dimethyl carbonate (DMC) technologies. Results show the energy consumption of CO2 capture of the Rectisol process is the lowest, 1.88 GJ/tCO2, followed by the DMC process, 2.10 GJ/tCO2, the CAP process, 3.64 GJ/tCO2, and the MEA process, 5.20 GJ/tCO2. The CO2 capture cost of the Re... [more]
Advanced Bioethanol Production: From Novel Raw Materials to Integrated Biorefineries
Aleta Duque, Cristina Álvarez, Pablo Doménech, Paloma Manzanares, Antonio D. Moreno
October 12, 2022 (v1)
Keywords: bio-based products, biochemical route, Biofuels, biomass fractionation
The production of so-called advanced bioethanol offers several advantages compared to traditional bioethanol production processes in terms of sustainability criteria. This includes, for instance, the use of nonfood crops or residual biomass as raw material and a higher potential for reducing greenhouse gas emissions. The present review focuses on the recent progress related to the production of advanced bioethanol, (i) highlighting current results from using novel biomass sources such as the organic fraction of municipal solid waste and certain industrial residues (e.g., residues from the paper, food, and beverage industries); (ii) describing new developments in pretreatment technologies for the fractionation and conversion of lignocellulosic biomass, such as the bioextrusion process or the use of novel ionic liquids; (iii) listing the use of new enzyme catalysts and microbial strains during saccharification and fermentation processes. Furthermore, the most promising biorefinery approa... [more]
Stabilization of Anaerobic Co-Digestion Process via Constant the Digestate Solids Content
Risu Na, Keisuke Uchitani, Kazuto Yoshida, Naoto Shimizu
October 12, 2022 (v1)
Keywords: anaerobic digestion, biogas, mass balance, solid content, specific methane yield
The process instability of anaerobic digestion (AD) is a common issue and may result in underperformance or short-term process failure. Extensive research has shown that total solids (TS) content in AD has a significant impact on system stability and performance. However, no study has examined the feasibility of stabilizing the AD process by maintaining constant TS content in the digestate. In this study, an innovative control approach based on constant TS content in the digestate during AD was developed using a mass balance equation. Two levels of TS content (desired values of 4% wet basis (w.b.) and 6% w.b.) were compared with conventional control. The process stability was examined by monitoring digestate components and pH. Substrate-specific methane yield (m3 CH4/kg VS) was used to assess the effectiveness of the controlled conditions. The results showed that the digestate TS content during AD can be controlled and that the digestion process can be stabilized by controlled conditio... [more]
Biodiesel Dry Purification Using Unconventional Bioadsorbents
Emilio Arenas, Stephanie M. Villafán-Cáceres, Yetzin Rodríguez-Mejía, Jonathan A. García-Loyola, Omar Masera, Georgina Sandoval
October 12, 2022 (v1)
Keywords: bioadsorbents, biodiesel, purification, waste cooking oil
The dry washing method is an alternative to replace water washing, thereby reducing the negative impacts of contamination. However, commercial adsorbents come from industrial processes that, due to their composition, may not be such a sustainable resource in the global biodiesel production process. In this study, the use of organic residues, such as sawdust, coconut fiber, nutshell, rice husk, and water hyacinth fiber, were proposed as bioadsorbents for the purification of biodiesel from waste cooking oil. Quality parameters such as the acid number, water content, and free and total glycerin content were evaluated and compared with those after purification with commercial adsorbents (Magnesol and Amberlite BD10DRY). Promising results were obtained using sawdust in the purification process, achieving a reduction in the acid number value of 31.3% respect to the unpurified biodiesel. Indeed, the reduction with sawdust was more efficient than with Amberlite BD10DRY (that increased the acid... [more]
Mesophilic Anaerobic Digestion of Hydrothermally Pretreated Lignocellulosic Biomass (Norway Spruce (Picea abies))
Nirmal Ghimire, Rune Bakke, Wenche Hennie Bergland
October 12, 2022 (v1)
Keywords: hot water extraction, hydrolysate, lignocellulosic biomass, mesophilic anaerobic digestion, Norway spruce
Hot water extraction (HWE) removes hemicellulose from woody biomass to give improved end products while producing a sugar-rich by-product stream, which requires proper treatment before disposal. Hot water extracted Norway spruce (Picea abies) at two different pretreatment conditions (140 °C for 300 min (H140) and 170 °C for 90 min (H170)) generated hydrolysate as a by-product, which was used in mesophilic anaerobic digestion (AD) as substrate. H140 gave a higher methane yield (210 NmL/g COD—chemical oxygen demand) than H170 (148 NmL/g COD) despite having a lower concentration of sugars, suggesting that different levels of inhibitors (furans and soluble lignin) and recalcitrant compounds (soluble lignin) affected the methane yield significantly. Organic loads (OLs) had a negative effect on the methane yield, as observed during AD of H170, while such an effect was not observed in the case of H140. This suggests that the decrease in methane yield (32%) of H170 compared to H140 is primaril... [more]
Comparative Life Cycle Assessment of Co-Processing of Bio-Oil and Vacuum Gas Oil in an Existing Refinery
Meirong Shi, Xin Zhao, Qi Wang, Le Wu
October 12, 2022 (v1)
Keywords: bio-oil, co-processing, Eco-indicator 99, FCC, LCA, vacuum gas oil
The co-cracking of vacuum gas oil (VGO) and bio-oil has been proposed to add renewable carbon into the co-processing products. However, the environmental performance of the co-processing scheme is still unclear. In this paper, the environmental impacts of the co-processing scheme are calculated by the end-point method Eco-indicator 99 based on the data from actual industrial operations and reports. Three scenarios, namely fast pyrolysis scenario, catalytic pyrolysis scenario and pure VGO scenario, for two cases with different FCC capacities and bio-oil co-processing ratios are proposed to present a comprehensive comparison on the environmental impacts of the co-processing scheme. In Case 1, the total environmental impact for the fast pyrolysis scenario is 1.14% less than that for the catalytic pyrolysis scenario while it is only 26.1% of the total impacts of the pure VGO scenario. In Case 2, the environmental impact of the fast pyrolysis scenario is 0.07% more than that of the catalyti... [more]
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