The Experts below are selected from a list of 4395 Experts worldwide ranked by ideXlab platform
Cigdem Eskicioglu - One of the best experts on this subject based on the ideXlab platform.
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effect of inoculum substrate ratio on mesophilic anaerobic digestion of Bioethanol Plant whole stillage in batch mode
Process Biochemistry, 2011Co-Authors: Cigdem Eskicioglu, Maryam GhorbaniAbstract:Abstract A study of anaerobic digestion of whole stillage from a dry-grind corn ethanol Plant was conducted to evaluate the possibility of replacing fossil fuel input of large ethanol Plants by using ethanol residues as digester feedstock. The effect of inoculum to substrate ratio (ISR) on biogas/methane production rates and ultimate yields was evaluated in mesophilic batch digesters. A first order kinetic model was evaluated for both volatile solids (VS) and total chemical oxygen demand (TCOD) removals. The results demonstrated that in an ISR range of 3.67–0.46 g/g on VS basis, kinetic constants ( k ) for both VS and TCOD removals decreased significantly, indicating an initial reactor overloading or substrate inhibition. However, despite the slower biodegradable rates from the reactors with ISRs of 0.46 and 0.92, none of the reactors experienced a chronic substrate inhibition. At the highest organic loading (ISR of 0.46 g/g), degradation was complete in 15–16 days. Biochemical methane potential assays indicated significant digestion potential (691–788 mL biogas and 401–458 mL CH 4 per g VS added at 0 °C, 1 atm) with organic removals between 76% and 94% in batch mode. Future studies will verify the anaerobic digestion potential of full-strength whole stillage at larger scale.
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anaerobic digestion of whole stillage from dry grind corn ethanol Plant under mesophilic and thermophilic conditions
Bioresource Technology, 2011Co-Authors: Cigdem Eskicioglu, Kevin Kennedy, Juan Marin, Benjamin StrehlerAbstract:Abstract Anaerobic digestion of whole stillage from a dry-grind corn-based ethanol Plant was evaluated by batch and continuous-flow digesters under thermophilic and mesophilic conditions. At whole corn stillage concentrations of 6348 to 50,786 mg total chemical oxygen demand (TCOD)/L, at standard temperature (0 °C) and pressure (1 atm), preliminary biochemical methane potential assays produced 88 ± 8 L (49 ± 5 L CH 4 ) and 96 ± 19 L (65 ± 14 L CH 4 ) biogas per L stillage from mesophilic and thermophilic digesters, respectively. Continuous-flow studies for the full-strength stillage (TCOD = 254 g/L) at organic loadings of 4.25, 6.30 and 9.05 g TCOD/L days indicated unstable performance for the thermophilic digester. Among the sludge retention times (SRTs) of 60, 45 and 30 days tested, the mesophilic digestion was successful only at 60 days-SRT which does not represent a practical operation time for a large scale Bioethanol Plant. Future laboratory studies will focus on different reactor configurations to reduce the SRT needed in the digesters.
Jhuma Sadhukhan - One of the best experts on this subject based on the ideXlab platform.
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techno economic evaluations for feasibility of sago based biorefinery part 2 integrated Bioethanol production and energy systems
Chemical Engineering Research & Design, 2016Co-Authors: Jhuma Sadhukhan, Denny K S NgAbstract:Abstract To reduce reliance on fossil fuel and environmental issues, alternative energy sources such as biomass are vital to be recovered and converted into value-added products. In sago industry, a huge amount of sago biomass (i.e., sago barks and fibres) is generated and discharged to the environment during sago starch extraction process (SSEP). In order to reduce environmental pollutants, the biomass can be utilised as feedstocks for energy, and Bioethanol production. Therefore, Part 1 of these articles in series presents a techno-economic analysis to examine the feasibility of sago biomass-based combined heat and power (CHP) system ( Wan et al., 2015a ); and Part 2 is to examine the feasibility of integrated Bioethanol production and energy systems. In this part, a conceptual integrated sago-based biorefinery (SBB) is envisioned and analysed based on the Bioethanol Plant study conducted by the National Renewable Energy Laboratory (NREL). Besides, techno-economic performance as well as environmental performance of this integrated SBB is evaluated via Aspen Plus software and a spreadsheet based yield prediction model. For the performance evaluation, various feedstocks such as sago fibres, barks and combined biomass (fibres and barks) are considered. In addition, techno-economic and environmental performance of the integrated SBB with on-site and off-site enzyme production as well as the impacts of labour cost on the economic performance of the integrated SBB is also evaluated. Based on the evaluation and analysis, the integrated SBB with combined biomass (fibres and barks) has the highest technical, economic and environmental performance amongst the sago biomass. A total of 4.75 t/d of Bioethanol and 252 kW/d of electricity are expected to be produced; and reduction of 16.32 tCO 2 equivalent/d of carbon dioxide emission is expected. In addition, the payback period of the integrated SBB with on-site enzyme production and using current available labour from SSEP is estimated as 6.6 years. Based on the analysis, it is noted that enzyme and labour costs are critical cost contributors to the new development of the integrated SBB and hence, a sensitivity analysis on such parameters is performed.
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economic value and environmental impact evei analysis of biorefinery systems
Chemical Engineering Research & Design, 2013Co-Authors: Elias Martinezhernandez, Grant M Campbell, Jhuma SadhukhanAbstract:The selection of product portfolios, processing routes and the combination of technologies to obtain a sustainable biorefinery design according to economic and environmental criteria represents a challenge to process engineering. The aim of this research is to generate a robust methodology that assists process engineers to conceptually optimise the environmental and economic performances of biorefinery systems. A novel economic value and environmental impact (EVEI) analysis methodology is presented in this paper. The EVEI analysis is a tool that emerges from the combination of the value analysis method for the evaluation of economic potential with environmental footprinting for impact analysis. The methodology has been effectively demonstrated by providing insights into the performance of a Bioethanol Plant as a case study. The systematisation of the methodology allowed its implementation and integration into a computer-aided process engineering (CAPE) tool in the spreadsheet environment.
Anton Friedl - One of the best experts on this subject based on the ideXlab platform.
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analysis and decrease of the energy demand of Bioethanol production by process integration
Applied Thermal Engineering, 2007Co-Authors: Martin Pfeffer, Walter Wukovits, Georg Beckmann, Anton FriedlAbstract:Process simulation was used to decrease the external heat demand during the production of Bioethanol by integration in a network of facilities for heat and power generation. Models for Bioethanol fermentation and purification process, the production of DDGS as well as production and utilization of biogas were developed to calculate the heat demand of Bioethanol-production and the amount of heat and power generated from residues of the Bioethanol process. Depending on the form of biogas utilization (CHP-Plant, biogas fired boiler) and the capacity of the Bioethanol Plant, the conversion of stillage from the Bioethanol process to biogas covers a considerable amount of the heat demand necessary for Bioethanol-production and purification.
Ofélia Q.f. Araújo - One of the best experts on this subject based on the ideXlab platform.
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Carbon dioxide management by chemical conversion to methanol: HYDROGENATION and BI-REFORMING
Energy Conversion and Management, 2016Co-Authors: Igor L. Wiesberg, Rita M.b. Alves, Paulo L.a. Coutinho, Jose Luiz De Medeiros, Ofélia Q.f. AraújoAbstract:Chemical conversion of carbon dioxide to methanol has the potential to address two relevant sustainability issues: economically feasible replacement of fossil raw materials and avoidance of greenhouse gas emissions. However, chemical stability of carbon dioxide is a challenging impediment to conversion requiring severe reaction conditions at the expense of increased energy input, therefore adding capital, operation and environmental costs, which could result in partial or total override of its potential sustainability as feedstock to the chemical and energy industries. This work investigates two innovative chemical destinations of carbon dioxide to methanol, namely a direct conversion through carbon dioxide hydrogenation (HYDROGENATION), and an indirect via carbon dioxide conversion to syngas through bi-reforming (BI-REFORMING). Process simulation is used to obtain mass and energy balances needed to support assessment of economic and environmental performance. A business scenario is considered where an industrial source of nearly pure carbon dioxide exists and an investment decision for utilization of carbon dioxide is faced. Due to uncertainties in prices of the raw materials, hydrogen (HYDROGENATION) and natural gas (BI-REFORMING), the decision procedure includes the definition of price thresholds to reach profitability. Sensitivity analyses are performed varying costs with greater uncertainty, i.e., carbon dioxide and methanol, and recalculating maximum allowable prices of raw materials. The analyses show that in a Brazilian scenario, BI-REFORMING is unlikely to be feasible, while HYDROGENATION would be viable, and with superior environmental performance, if the price of hydrogen remains inferior to 1000 US$/t. A scenario of cheap natural gas at 2.74 US$/MMBtu, as in the United States, would favor BI-REFORMING, which yields returns that are superior to those of HYDROGENATION even with hydrogen prices as low as 800 US$/t. The integrated scenario of HYDROGENATION has an advantage of about 50 US$/t in the methanol price in comparison to its non-integrated alternative. The environmental analysis revealed that both routes contribute to reduce global warming potential, and the reduction is intensified with a clean energy source (hydropower), with additional environmental benefit of decreasing acidification potential. For fossil energy supply, HYDROGENATION succeeds to reduce 87% of the emissions from the carbon dioxide source (Bioethanol Plant). Moving to a clean energy scenario increases the efficiency to 98%. BI-REFORMING is unable to reduce emissions (rather increasing it by 105%) in the fossil based energy scenario, however, for clean energy supply, it emits only 46% of the input of carbon dioxide from the Bioethanol Plant.
Maryam Ghorbani - One of the best experts on this subject based on the ideXlab platform.
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effect of inoculum substrate ratio on mesophilic anaerobic digestion of Bioethanol Plant whole stillage in batch mode
Process Biochemistry, 2011Co-Authors: Cigdem Eskicioglu, Maryam GhorbaniAbstract:Abstract A study of anaerobic digestion of whole stillage from a dry-grind corn ethanol Plant was conducted to evaluate the possibility of replacing fossil fuel input of large ethanol Plants by using ethanol residues as digester feedstock. The effect of inoculum to substrate ratio (ISR) on biogas/methane production rates and ultimate yields was evaluated in mesophilic batch digesters. A first order kinetic model was evaluated for both volatile solids (VS) and total chemical oxygen demand (TCOD) removals. The results demonstrated that in an ISR range of 3.67–0.46 g/g on VS basis, kinetic constants ( k ) for both VS and TCOD removals decreased significantly, indicating an initial reactor overloading or substrate inhibition. However, despite the slower biodegradable rates from the reactors with ISRs of 0.46 and 0.92, none of the reactors experienced a chronic substrate inhibition. At the highest organic loading (ISR of 0.46 g/g), degradation was complete in 15–16 days. Biochemical methane potential assays indicated significant digestion potential (691–788 mL biogas and 401–458 mL CH 4 per g VS added at 0 °C, 1 atm) with organic removals between 76% and 94% in batch mode. Future studies will verify the anaerobic digestion potential of full-strength whole stillage at larger scale.