Ethanol Plant Research Articles

Former DuPont ethanol plant is reborn to make renewable methane

Former DuPont ethanol plant is reborn to make renewable methane

Removal of a mixture of formaldehyde and methanol vapors in biotrickling filters under mesophilic and thermophilic conditions: Potential application in ethanol production

ABSTRACT Ethanol is a significant source of energy as a biofuel; however, its production using corn involves the generation of harmful emissions from both fermentation tanks and dryers. Scrubbers control the emissions from fermentation tanks, while the emissions from the dryers are controlled by regenerative thermal oxidizers. Potential alternatives to these energy- and water-intensive technologies are biotrickling filters (BTFs). In this study, two BTFs were operated in parallel to treat formaldehyde and methanol emissions in a volumetric ratio of 4:1, one at 25°C (mesophilic), and the other at 60°C (thermophilic). The mesophilic BTF simulated emissions from fermentation tanks, while the thermophilic BTF simulated emissions from dryers. Both beds were operated at an empty bed residence time of ~30 s and influent formaldehyde concentrations of 20, 50, and 100 parts per million per volume (ppmv). Formaldehyde polymerization was reduced in this study by adding NaOH to pH levels of 7.0–7.4 and heating the solution to a temperature of 60°C. BTFs have successfully removed formaldehyde at typical ethanol plants emissions ~21 ppmv. The BTF technology have the potential in replacing the conventional air treatment methods used at ethanol plants. Implications: Currently, ethanol plants remove and treat hazardous air pollutants (HAPs) using wet scrubbers from the fermenter off-gasses and using thermal oxidizers to combust off-gasses. The utilization of biotrickling filters (BTFs) for HAP removal generally and formaldehyde particularly has wide implication in the field of renewable energy. Utilizing BTFs in the 200+ ethanol plants in USA will save cost and reduce water and energy needs significantly. BTFs can reduce an ethanol plant’s carbon intensity (CI) by 1 to 3 g CO2/MJ. This can result in roughly $50 million per year in additional revenue in Nebraska for instance.

Life‐cycle greenhouse gas emissions reduction potential for corn ethanol refining in the USA

AbstractThis study evaluates how low‐carbon production technologies applicable to ethanol plants may reduce the life‐cycle greenhouse gas emission (GHG) intensities of corn ethanol production in the USA. Results indicate that options focusing on incremental energy efficiency (e.g., combined heat and power) and yield improvements have a limited impact on GHG reductions. To achieve deep decarbonization (>50% GHG reduction compared to current corn ethanol production), a fuel switch from natural gas (NG) to alternative low‐carbon fuels is needed. Replacing 50% of NG demand at ethanol plants with syngas from biomass through gasification or renewable natural gas from animal waste could achieve significant GHG reductions (11.7–23.5 g CO2e/MJ ethanol). Adding multiple technologies, including carbon capture and storage, to existing ethanol plants may further reduce GHG emissions to −18.4 g CO2e MJ−1 ethanol (including land‐use change emissions), which is 120% lower than the carbon intensity of pure gasoline. These results could inform how the ethanol industry could move toward net‐zero ethanol production. © 2022 UChicago Argonne, LLC, Operation of Argonne National Laboratory. Biofuels, Bioproducts and Biorefining published by Society of Industrial Chemistry and John Wiley & Sons Ltd.

Biomass feeding in cellulosic ethanol projects: An underestimated issue?

Projects unsuitable for specific types of biomass can cause serious flow problems, capable of making the production unfeasible. This paper aims to identify whether there was available technological knowledge proper to design equipment that would guarantee a linear flow feed of biomass as raw material, searching patents applications, that is an efficient tool widely used to analyse technological scenarios. The results showed an increase in the patents number dealing with specific types of biomass as of 2016 – a pick of 14 patent application per year, but still in a very small number if compared to the number of patents applied on biomass in general – a pick of 5.974 patent application per year. Analysing together with problems occurred in cellulosic ethanol plants, these results seem to support the hypothesis that new technological developments will still be needed to allow plants to work efficiently with biomass as feedstock. This study brings a new approach to discussions about the challenges faced by second-generation ethanol plants, both in the search methodology developed for this research and in bringing the theme of biomass feeding and handling to the centre of debates on the next challenges for industrial pants using lignocellulosic biomass as feedstock.

Modeling and Simulation of Batch Sugarcane Alcoholic Fermentation Using the Metabolic Model

The present work sought to implement a model different from the more traditional ones for the fermentation process of ethanol production by the action of the fungus Saccharomyces cerevisiae, using a relevant metabolic network based on the glycolytic Embden–Meyerhof–Parnas route, also called “EMP”. We developed two models to represent this phenomenon. In the first model, we used the simple and unbranched EMP route, with a constant concentration of microorganisms throughout the process and glucose as the whole substrate. We called this first model “SR”, regarding the Portuguese name “sem ramificações”, which means “no branches”. We developed the second model by simply adding some branches to the SR model. We called this model “CR”, regarding the Portuguese name “com ramificações”, which means “with branches”. Both models were implemented in MATLABTM software considering a constant temperature equal to 32 °C, similar to that practiced in sugar and ethanol plants, and a wide range of substrate concentrations, ranging from 30 to 100 g/L, and all the enzymes necessary for fermentation were already expressed in the cells so all the enzymes showed a constant concentration throughout the fermentation. The addition of common branches to the EMP route resulted in a considerable improvement in the results, especially predicting ethanol production closer to what we saw experimentally. Therefore, the results obtained are promising, making adjustments consistent with experimental data, meaning that all the models proposed here are a good basis for the development of future metabolic models of discontinuous fermentative processes.

Prediction of fumonisins B1 and B2 in corn distiller's dried grains with solubles through near-infrared reflectance spectroscopy.

Distiller's dried grains with solubles (DDGS) are coproducts of the biofuel industries that use corn as raw material. This cereal is commonly contaminated by mycotoxins, including fumonisins (FBs), which can pose a serious health threat to humans and animals. Corn DDGS are typically used as a protein-rich animal feed. As mycotoxins from the original cereal grains become concentrated in DDGS, mycotoxicological monitoring is highly required before their use as ingredient in the industry. This work aimed to develop a methodology for predicting fumonisins B1 (FB1 ) and B2 (FB2 ) in corn DDGS using near-infrared reflectance spectroscopy (NIRS) technology associated with chemometric methods. One hundred and ninety corn DDGS samples originating from Brazilian ethanol plants and feed mills were included in this assessment. Two datasets were created: one for calibration (132 samples) and another for external validation (58 samples). Partial least squares regression and a cross-validation approach were applied to build the models. Liquid chromatography coupled to tandem mass spectrometry was used as the reference methodology. Calibration results of correlation coefficient and residual prediction deviation for FB1 and FB2 were, respectively, 0.90 and 0.88; and 2.16 and 2.06. Values of the external validation dataset were compared and no statistical difference was found between groups, indicating a satisfactory predictive ability and confirming the potential of NIRS to predict fumonisins in corn DDGS. © 2022 Society of Chemical Industry.

Management Information System for Milling Section at Sugar Factory

Abstract: One of the most important goals in any organization is increasing work force productivity Information systems, Systems are the responsibility of their data and their processing of information within the organization and managers to provide information on important economic decisions making. Hutatma Sahakari Sakhar Karakhana. Ltd. is well known sugar industry having 5000 tccpd to 6000 tccpd capability along with new constructed new ethanol plant and using different facility in this factory such as leveller, fibrizor, kicker, TRPS rolling mill, elevator, boiler, pan and centrifuge. Management Information System (MIS) in increasing human resource productivity. Savings in labor, increased consumer surplus, improved customer service quality, improved organizational efficiency, quicker response to customers, deeper knowledge and understanding of customers. The purpose of this Project is to surveying the effect of management information system of productivity and its elements such as work speed, work cost, work accuracy (efficiency) and supervision and control status improvement, planning status improvement and make decision status improvement (effectiveness) of overall machine, man and material to improve performance of all over machinery, information systems.

Can biogas-producing sugarcane biorefineries techno-economically outperform conventional ethanol production? Deciphering the way towards maximum profitability

Energy transition patterns point towards a gas-fueled society in coming decades, whereby natural gas plays an initial leading role. Naturally, biogas will become the primary energy source once gas reserves are depleted, which motivates investigating approaches to efficiently supply biogas-fueled facilities. Sugarcane biorefineries have the potential to become leading biogas producers, based on recent successful experiences on the anaerobic digestion (AD) of primary sugarcane byproducts, such as molasses. This study assessed the techno-economics of operating AD-based sugarcane biorefineries producing electricity or biomethane as alternatives to conventional ethanol production. Scenarios including the processing of molasses or combining juice and molasses in single- and two-stage (acidogenesis + methanogenesis) AD were considered. Detailed energy balance analyses demonstrated that biogas production/processing is much more efficient than ethanol production, with energy return on investment levels (4.33–8.67) at least 4-fold higher than in the case of ethanol (1.06–1.32). Despite the relevant energetic contribution of H2 from substrate fermentation in some cases (up to 9%), extremely high production costs eliminated any trace of economic competitiveness for H2-producing biorefineries (internal rate of return – IRR < 16%) compared to ethanol plants (IRR = 24.9%). However, investing on substrate fermentation (without H2 production) coupled to NaOH-supplied methanogenesis could maintain electricity- (IRR = 26.9%) or biomethane- (IRR = 25.1%) producing plants economically more attractive than ethanol production. While relatively minimum increments in the price of electricity would be necessary to support the first plants, both reducing investment costs coupled with valorizing biomethane would be essential in the latter. Hence, biogas-producing biorefineries may be more than a match for ethanol facilities, and sugarcane has a great potential to play the role of a leading feedstock within the context of energy transition.

Determinação de regiões para instalação de usinas sucroalcooleiras flex: uma abordagem multicritério para localização

Abstract The development of sugarcane varieties has allowed Brazilian ethanol plants to operate longer during the harvest, however, in the off-season they remain idle due to the absence of biomass. To increase energy safety and guarantee supply in critical periods, it has been proposed to adapt ethanol plants to the flex-biomass model, allowing the production of biofuel from corn as well. Considering the costs of building or adapting a plant, strategically defining the location is essential for optimizing ethanol production. The aim of this study is to verify whether the combination of location criteria can identify the most suitable regions for the construction of new plants and map them. The method consists of the Analytical Hierarchical Process (AHP) with GIS techniques. We found two large continuous regions suitable for the construction of new flex ethanol plants, corresponding together to 11% of the study area. However, in these two suitable regions, only 0.33% of the territory has more than 90% suitability. Therefore, we confirmed the existence of more suitable regions and concluded that the mapping of these areas enhances the resources application, avoiding installation in inappropriate areas.

Ethanol Plant Investment and Government Policy: A Dynamic Structural Econometric Model

Ethanol Plant Investment and Government Policy: A Dynamic Structural Econometric Model

Multicriteria analysis by PROMETHEE-SAPEVO-M1 method: choice of Brazilian sugar and ethanol plants for biomethane production

Given the need for cleaner energy sources associated with the ESG (Environmental, social and corporate governance) policy, the work in question is a case study referring to the project to expand biomethane production in national territory, especially for industrial commercialization. By applying the Value Focused Thinking (VFT) methodology, the study initially seeks the approach based on the values of decision-makers, these being three professionals in the energy sector. After the central objective of supporting decision-making, the hybrid method PROMETHEE-SAPEVO-M1 was used, characterized by the possibility of evaluating quantitative data and qualitative variables. To this end, the modeling occurred through the software of the PROMETHEE-SAPEVO-M1 method to clarify the best plants, because of the range of possibilities in the national territory, for project implementation and subsequent production of biomethane for industrial use. As a result, we verified that São Paulo is the best alternative for applying the investment in biomethane production.

Synergistic integration of wastewaters from second generation ethanol plant for algal biofuel production: an industrially relevant option.

The present study provides an integrated method for utilizing the wastewaters from second generation (2G) ethanol pretreatment plant for microalgal biomass and lipid production. The study was conducted using a mixture of wastewaters (referred as MW; pH 4.3) generated after washing of acidic and alkaline-soaked lignocellulosic biomass prior to pretreatment process. The growth studies indicated that the thermotolerant strain of Chlorella pyrenoidosa (C. pyrenoidosa) M18 exhibited higher cell proliferation in wastewater as compared to freshwater. About 20-25% enhancement in biomass (509mg L-1 d-1 ± 3.09) and lipid productivity (146mg L-1 d-1 ± 1.34) was observed in MW. The total chlorophyll content and variable fluorescence by maximum fluorescence (Fv/Fm) ratio of strain cultivated in MW were 10.32µgmL-1 and 0.75, respectively. The use of MW also enhanced the content of saturated and monounsaturated fatty acids in total lipid. The exhausted wastewater medium obtained after harvesting the auto-flocculated biomass was also reused up to three successive growth cycles. The recycled medium without any nutrient addition could be used for two subsequent rounds with enhanced biomass (520mg L-1 d-1 ± 4.07) and lipid (157.71mg L-1 d-1 ± 1.09) productivities. This synergistic approach of cultivating thermotolerant microalgae with wastewater from 2G pretreatment plant provides an economical setup for development of commercial algal biofuel technology.

Morphological, anatomical and antibacterial characteristics of Persicaria maculosa Gray plants growing in Lang Sen Wetland Reserve, Long An province, Vietnam

This study aimed to understand the adaptation characteristics of species Persicaria maculosa to living conditions and to add data on them as folk medicinal plants of Vietnam. Research methods included analysis of external morphological characteristics and microscopic structure of stems, leaves and roots. The antibacterial activities of ethanol plant extracts on four bacterial strains were also conducted through agar well diffusion method. The results showed that the plants had formed morphological and anatomical features to adapt to waterlogging and shade conditions. The leaf extracts from the concentrations of 600 to 1,000 mg/L had bacteriostatic activities against all four experimental strains with the bacterial inhibition zones from 2.39 to 10.91 mm, in which inhibition of Bacillus cereus was the best.

A Systematic Literature Review of Multi-Criteria Analysis Model Methods on Sustainability Weighting for Ethanol Plant

The sustainability weighting is crucial as it is practically implemented into sustainability evaluation, especially in industrial development. Sustainability is about the interconnection between three aspects of sustainability impact such as economic impact, environmental impact, and social impact. Multi-Criteria Analysis (MCA) model play important roles to measure the weighting for each impact according to the scenario and criteria selected based on scientific rules and robust statistical methods. However, there were insufficient studies on the existing literature sustainability weighting model from MCA method for the ethanol plant. Hence, the present paper demonstrates a systematic literature review of MCA model methods on sustainability weighting for the ethanol plant. There are two steps involved in systematic literature reviews: formulation of the research question and systematic searching strategies consisting of identification, screening, eligibility, quality appraisal, data abstraction and analysis. The review is based on leading databases; Scopus – ScienceDirect, Springer, Taylor and Francis, and one supporting database – Google Scholar. From the review, the preferable MCA weighting model for sustainability evaluation of ethanol plants is ‘integrated Analytical Hierarchy Process (AHP)’ rather than ‘standalone AHP’. The paper offered a significant contribution to the body of knowledge and sustainability evaluation purposes.

Effect of Vinasse Recycling on Effluent Reduction from Distilleries: Case of Metehara Distillery, Ethiopia

This study was conducted at the ethanol plant of Metehara sugar factory, at a laboratory scale, to assess the effect of recycling vinasse into the fermentation process on effluent reduction. Vinasse is an effluent produced from distilleries. The experimental design included vinasse concentrations at 4 dilution rates (0 (control), 20, 35, 50, and 65% of process water) with 2 replicates and 6 responses, as follows: ethanol yield, fermentation efficiency, residual sugar concentration, cell count, cell viability, and calcium oxide content. In this study, the actual operational parameters of the ethanol plant were maintained during the experiment. The result of the experiment indicates that, with up to 20% vinasse recycling, there was no influential impact on the ethanol yield, the fermentation efficiency, the residual sugar concentration, or the calcium oxide content, attributable to the recycling, as compared to the control. Above 20% vinasse recycling, ethanol yield and fermentation efficiency decreased sharply from those of the control. In addition, with 20% vinasse recycling put into practice, the amount of vinasse generated will be reduced by about 19.5% and about 114.2 tons of water will be saved per day. Moreover, the excess amount of vinasse produced by the distillery, which is beyond the handling capacity of bio-compost plant of the distillery, will reduce from 105 to 36.8 tons per day. Therefore, it is possible to recycle vinasse into the fermenter up to 20% on dilution water of Metehara distillery, without causing any impacts on the distillery’s performance.

Oil Recovery from Dry Grind Ethanol Plant Coproducts Using Ethanol

Corn ethanol bio-refineries are seeking economic processing strategies for recovering oil from their coproducts. The addition of ethanol can be an efficient method to recover the oil from the coproducts as the industry has available ethanol. This study considered the effects of ethanol on oil recovery from distillers’ dried grains with solubles (DDGS) and oil partitioning from whole stillage (WS) on a laboratory scale. Ethanol was added with original and heavier fraction DDGS in different temperatures (room temperature ~20 °C, 30 °C, 40 °C, and 50 °C) and solids loadings (20%, 30%, and 40%), and their effects on oil recovery were evaluated. The whole stillage was incubated with ethanol at room temperature (~20 °C) and 50 °C separately to analyze WS’s oil distribution in the liquid and solid phases. The amount of recovered oil from the original and heavier fractions of DDGS varies from 25–45% and 45–70%, respectively, with an increment of temperature. Increasing solids loadings up to 30% had no effect on oil recovery from either DDGS sample. Ethanol treatment in WS resulted in 8–10% higher wet yield of liquid fraction and 17–20% of oil increase in liquid fraction than the control treatment. It is also notable that temperature positively impacted oil partitioning from WS. The results showed that ethanol could improve oil recovery from DDGS and oil partition in WS by varying different process conditions. This outcome is beneficial to ethanol plants to increase corn oil yield using their existing setup and in-situ product.

Techno-economic assessment of poly-generation pathways of bioethanol and lignin-based products

In this study, two fermentation-pyrolysis pathways for cellulosic ethanol production were established to improve the economy of cellulosic ethanol plants by lignin-rich residue pyrolysis. Techno-economic assessment (TEA) was conducted for both novel pathways compared with conventional fermentation-combustion pathway based on biomass Arundo donax. Pathway simulation showed that compared with the fermentation-combustion pathway, fermentation-pyrolysis pathway produced extra bio-char and hydrocarbon fuels except 256,000 m3 of ethanol each year. Economic analysis showed that the Minimum Ethanol Selling Price (MESP) of fermentation-combustion pathway was 1.623$/gal. The MESP of fermentation-pyrolysis A pathway and fermentation-pyrolysis B pathway was 1.673$/gal and 1.494$/gal respectively. The MESP of fermentation-pyrolysis B pathway indicated a potential process of lignin pyrolysis applied in cellulosic ethanol plants in the future. Sensitivity analysis indicated that price change of A. donax and plant scale both have a great impact on the MESP.

Selection of Superior Yeast Strains for the Fermentation of Lignocellulosic Steam-Exploded Residues.

The production of lignocellulosic ethanol calls for a robust fermentative yeast able to tolerate a wide range of toxic molecules that occur in the pre-treated lignocellulose. The concentration of inhibitors varies according to the composition of the lignocellulosic material and the harshness of the pre-treatment used. It follows that the versatility of the yeast should be considered when selecting a robust strain. This work aimed at the validation of seven natural Saccharomyces cerevisiae strains, previously selected for their industrial fitness, for their application in the production of lignocellulosic bioethanol. Their inhibitor resistance and fermentative performances were compared to those of the benchmark industrial yeast S. cerevisiae Ethanol Red, currently utilized in the second-generation ethanol plants. The yeast strains were characterized for their tolerance using a synthetic inhibitor mixture formulated with increasing concentrations of weak acids and furans, as well as steam-exploded lignocellulosic pre-hydrolysates, generally containing the same inhibitors. The eight non-diluted liquors have been adopted to assess yeast ability to withstand bioethanol industrial conditions. The most tolerant S. cerevisiae Fm17 strain, together with the reference Ethanol Red, was evaluated for fermentative performances in two pre-hydrolysates obtained from cardoon and common reed, chosen for their large inhibitor concentrations. S. cerevisiae Fm17 outperformed the industrial strain Ethanol Red, producing up to 18 and 39 g/L ethanol from cardoon and common reed, respectively, with ethanol yields always higher than those of the benchmark strain. This natural strain exhibits great potential to be used as superior yeast in the lignocellulosic ethanol plants.

ADM to pivot from ethanol to jet fuel

Most of the ethanol made in the US today is blended with gasoline for use in cars. ADM, one of the largest ethanol producers, plans to divert half its supply to be made into jet fuel instead. ADM and the biobased chemical maker Gevo have signed a letter of intent that calls for Gevo to take 3.4 billion L per year of ADM’s corn ethanol output and convert it into 1.9 billion L of sustainable aviation fuel (SAF) and other hydrocarbons starting in 2025. ADM makes the ethanol at three plants in the Midwest. CEO Juan Luciano said in an investor call that ADM is reducing its exposure to ethanol for blending with gasoline because of volatility in that market. ADM is also selling an ethanol plant in Peoria, Illinois, to Houston-based BioUrja Group. The core of Gevo’s process is a set of methods to convert ethanol to ethylene. From

Corn ethanol in the Midwestern USA: Local competition, entry and agglomeration

Abstract This article analyzes the entry of corn-ethanol plants in the Midwestern USA, where the majority of corn in the USA is grown, during the second US ethanol boom. In particular, we examine whether the presence of existing ethanol plants affects ethanol plant entry decisions at the county level using discrete response panel models. There are two main channels through which existing ethanol plants may affect ethanol plant entry decisions: a competition effect and an agglomeration effect. Our results show that existing ethanol plants have a negative effect on the probability of ethanol plant entry in a given county. The net negative competition effect dissipates with distance. We also find that existing conglomerates and large ethanol producing firms in neighboring counties have a positive effect on ethanol plant entry, while existing singlet plants in neighboring counties do not. These results provide evidence for both local competition among ethanol plants within counties, as well as possible agglomeration benefits from existing conglomerates and large ethanol producing firms in neighboring counties.