Design and techno-economic evaluation of microbial oil production as a renewable resource for biodiesel and oleochemical production

Experimental results from the open literature have been employed for the design and techno-economic evaluation of four process flowsheets for the production of microbial oil or biodiesel. The fermentation of glucose-based media using the yeast strain Rhodosporidium toruloides has been considered. Biodiesel production was based on the exploitation of either direct transesterification (without extraction of lipids from microbial biomass) or indirect transesterifaction of extracted microbial oil. When glucose-based renewable resources are used as carbon source for an annual production capacity of 10,000 t microbial oil and zero cost of glucose (assuming development of integrated biorefineries in existing industries utilising waste or by-product streams) the estimated unitary cost of purified microbial oil is $3.4/kg. Biodiesel production via indirect transesterification of extracted microbial oil proved more cost-competitive process compared to the direct conversion of dried yeast cells. For a price of glucose of $400/t oil production cost and biodiesel production cost are estimated to be $5.5/kg oil and $5.9/kg biodiesel, correspondingly. Industrial implementation of microbial oil production from oleaginous yeast is strongly dependent on the feedstock used and on the fermentation stage where significantly higher productivities and final microbial oil concentrations should be achieved.

O planejamento estratégico do capital humano como fator de desenvolvimento sustentável das organizações na agroenergia: estudo de caso

O objetivo desta tese é analisar, orientar e indicar algumas formas de mensuração de resultados das ações ou programas na área de Gestão de Pessoas ao longo dos anos, bem como de novas tendências no setor de agroenergia. O trabalho procura também propor práticas de planejamento estratégico e, indicadores para as organizações com foco no desenvolvimento e nas mudanças previstas nas organizações, no mercado de trabalho, nos modelos de gestão e de negócios do segmento de produção de cana-de-açúcar para os próximos anos. No estudo são analisados as transformações organizacionais, novos desafios competitivos do presente e do futuro, e a forma como a área de Recursos Humanos nas diversas organizações do setor, tem acompanhado tal processo, verificando o impacto dessas ações em um contexto de mudanças nos processos da cadeia agrícola (mecanização do plantio, colheita,.dentre outros), da cadeia industrial (biorefinarias, etanol de segunda geração, gaseificação...dentre outros), e no desenvolvimento organizacional e humano como parte integrante de um programa de sustentabilidade das organizações. São abordados metodologias, sistemas e ferramentas de planejamento estratégico, e mensuração propostas por certos autores que visam a demonstrar o impacto das estratégias e as ações na Gestão de Pessoas em direção ao cumprimento das metas e objetivos das organizações, em um cenário de forte crescimento interno e global do mercado de bioenergia. Nesse cenário, expõe-se e discute-se como as empresas do setor sucroalcooleiro utilizam, na prática, essas metodologias e os indicadores de performance da área frente às necessidades, e indicam-se as melhores práticas e ferramentas que visam a facilitar os processos decisórios, o uso de métricas de Recursos Humanos para previsão e acompanhamento do Capital Humano, e a otimização dos recursos e dos investimentos frente aos novos desafios do setor. Embora já se notem várias iniciativas visando a tornar a Gestão de Pessoas um fator estratégico para as organizações da agroenergia, a pesquisa identificou que a área de Recursos Humanos está evoluindo nessa direção e pode contribuir de forma efetiva para a melhor performance e sustentabilidade dos negócios. Palavras chaves: Cana-de Açúcar, Estratégia Organizacional, Capital Humano

Avaliação de projetos de investimento em cogeração de energia utilizando bagaço de cana-de-açúcar em biorrefinarias a partir do uso da teoria das opções reais

O cenário de continuo aumento do consumo de derivados do petróleo aliado a conscientização de que é necessário existir um equilíbrio com relação a exploração de recursos naturais e preservação do meio ambiente, vem impulsionando a busca por fontes alternativas de energia. Esse crescente interesse vem se aplicando a geração de energia a partir de biomassa da cana de açúcar, que vem se tornando cada vez mais comuns no Brasil, porém ainda existe um imenso potencial a ser explorado. Dentro deste contexto, se torna relevante a tomada de decisão de investimentos em projetos de cogeração e este trabalho busca incrementar a analise e tomada de decisão com a utilização da Teoria das Opções Reais, uma ferramenta de agregação de valor às incertezas, cabendo perfeitamente ao modelo energético brasileiro, onde grandes volatilidades do preço de energia são observadas ao longo dos anos. O objetivo do trabalho é determinar o melhor momento para uma biorrefinaria investir em unidades de cogeração. A estrutura do trabalho foi dividida em três cenários de porte de biorrefinarias, as de 2 milhões de capacidade de moagem de cana-de-açúcar por ano, as de 4 milhões e as de 6 milhões, visando assim ter uma representação amostral das biorrefinarias do país. Além disso, analisaram-se três cenários de volatilidade atrelados ao preço futuro de energia, dado que a principal variável de viabilização deste tipo de projeto é o preço de energia. As volatilidades foram calculadas de acordo com histórico do ambiente regulado, o dobro do ambiente regulado e projeção de PLD, representando, respectivamente, níveis baixos, médios e altos, de volatilidade do preço de energia. Após isso, foram elaboradas as nove árvores de decisão, que demonstram para os gestores de investimento que em um cenário de baixa volatilidade cria-se valor estar posicionado e ter a opção real de investir ou adiar investimento para qualquer porte de usina. No cenário de média volatilidade de preço, aconselha-se ao gestor estar posicionado em usinas de médio a grande porte para viabilização do investimento. Por fim, quando o cenário de preços é de grande volatilidade, tem-se um maior risco e existe a maior probabilidade de viabilização do investimento em usinas de grande porte.

Determinação de parâmetros de transferência de massa do processo de extração supercrítica

A extração com fluido supercrítico de materiais líquidos e sólidos despertou o interesse para aplicações industriais nas últimas décadas, mais particularmente sob o conceito de química verde e biorrefinarias, portanto é fundamental que se faça uma modelagem desse processo a fim de otimizar as condições operacionais e simular o processo. O objetivo geral deste trabalho consiste na determinação de parâmetros de transferência de massa do processo de extração supercrítica de matriz sólida, empregando o dióxido de carbono como solvente, a partir de dados cinéticos de extração e na avaliação sistemática de cinco modelos matemáticos para descrever as cinéticas de extração dos óleos da polpa e da casca do buriti, do óleo de açaí de da oleoresina de cúrcuma, medidas no Laboratório de Extração Supercrítica, da Faculdade de Engenharia Química (UFPA), a fim de contribuir para o estudo de ampliação de escala e análise de custo de produção. Foram avaliados os modelos de Tan e Liou, Goto et al. (1993), Martinez et al. (2003), Esquível et al. (1999), e Sovová (1994). A modelagem das cinéticas de extração foi realizada utilizando aplicativos computacionais desenvolvidos e validados neste trabalho a partir de diferentes dados experimentais publicados na literatura. Diante de 40 cinéticas medidas com diferentes equipamentos de extração, configurações de leito, tipos de matérias primas, preparo dos materiais, pressão e temperatura e outros parâmetros de processo (com destaque ao rendimento global e a vazão de solvente), foi construído um panorama dos resultados acerca da capacidade dos modelos de transferência de massa em descrever as mais diferentes curvas globais de extração. De forma geral, os modelos de Goto et al. (1993) e Sovová (1994) apresentaram as melhores previsões aos dados experimentais das matérias primas tratadas neste trabalho com menores valores de quadrado, erros relativo, faixa de erro e desvios padrão e valores de R² próximos da unidade.

Polihidroxialcanoatos (PHAs): bioprospecção de micro-organismos e produção a partir de glicerol

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Energetic-environmental assessment of a scenario for Brazilian cellulosic ethanol

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Thermal Characteristics of Lignin Residue from Industrial Processes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Studies on the application of Myceliophthora thermophila JCP1-4 cellulases cocktail on sugarcane bagasse pretreated by different methods

The hydrolysis step for sugar production in biorefineries is crucial for the sequential processes involved and cellulases cocktails behave differently according to the pretreatment employed. In this study, the application of the cellulases cocktail produced by the fungus Myceliophthora thermophila JCP1-4 was studied on the saccharification of sugarcane bagasse pretreated by ozonolysis and thermic ferric nitrate (TFN), and the results were compared with commercial enzymes (Novozymes Celluclast 1.5L, Novozym 188). The fungal cellulases cocktail hold an activity of FPU:β-glucosidase of 1:4(U/mL); time, temperature, FPU by g of cellulose load and percentage of dry matter (DM) were studied. The analysis of central composite design of TFN pretreated showed that fungal cellulases works better in DM values of 3–3.5% (4.5% for commercial), temperatures higher than 50 °C (<45 °C for commercial) and 15FPU for both; commercial enzymes yielded 7.78 g/L of reducing sugars and the fungal enzymes 5.42 g/L. With the ozone pretreated, the fungal enzymes presented a higher thermostability with faster kinects, being able to produce 5.56 g/L of reducing sugars (60 °C, 8 h), against 5.20 g/L for commercial enzymes (50 °C, 24 h), (10FPU, 3%DM for both). The FPU derivate analysis revels better yields with 7.5FPU, and the increase of DM to 7.5% resulted 13.28 g/L of reducing sugars.

Development of a biorefinery scheme for the valorization of olive mill wastewaters and grape pomaces

In the Mediterranean area, olive mill wastewater (OMW) and grape pomace (GP) are among the major agro-industrial wastes produced. These two wastes have a high organic load and high phytotoxicity. Thus, their disposal in the environment can lead to negative effects. Second-generation biorefineries are dedicated to the valorization of biowaste by the production of goods from such residual biomasses. This approach can combine bioremediation approaches to the generation of noble molecules, biomaterials and energy. The main aim of this thesis work was to study the anaerobic digestion of OMW and GP under different operational conditions to produce volatile fatti acids (VFAs) (first stage aim) and CH4 (second stage aim). To this end, a packed-bed biofilm reactor (PBBR) was set up to perform the anaerobic acidogenic digestion of the liquid dephenolized stream of OMW (OMWdeph). In parallel, the solid stream of OMW (OMWsolid), previously separated in order to allow the solid phase extraction of polyphenols, was addressed to anaerobic methanogenic digestion to obtain CH4. The latter experiment was performed in 100ml Pyrex bottles which were maintained at different temperatures (55-45-37°C). Together with previous experiments, the anaerobic acidogenic digestion of fermented GP (GPfreshacid) and dephenolized and fermented GP (GPdephacid) was performed in 100ml Pyrex bottles to estimate the concentration of VFAs achievable from each aforementioned GPs. Finally, the same matrices of GP and not pre-treated GP (GPfresh) were digested under anaerobic methanogenic condition to produce CH4. Anaerobic acidogenic and methanogenic digestion processes of GPs lasted about 33 days. Instead, the anaerobic acidogenic and methanogenic digestion process of OMWs lasted about 121 and 60 days, respectively. Each experiment was periodically monitored by analysing volume and composition of produced biogas and VFA concentration. Results showed that VFAs were produced in higher concentrations in GP compared to OMWdeph. The overall concentration of VFAs from GPfreshacid was approximately 39.5 gCOD L-1, 29 gCOD L-1 from GPdephacid, and 8.7 gCOD L-1 from OMWdeph. Concerning the CH4 production, the OMWsolid reached a high biochemical methane potential (BMP) at a thermophilic temperature (55°) than at mesophlic ones (37-45°C). The value reached was about 358.7 mlCH4 gSVsub-1. In contrast, GPfresh got a high BMP but at a mesophilic temperature. The BMP was about 207.3 mlCH4 gSVsub-1, followed by GPfreshacid with about 192.6 mlCH4 gSVsub-1 and lastly GPdephacid with about 102.2 mlCH4 gSVsub-1. In summary, based on the gathered results, GP seems to be a better carbon source for acidogenic and methanogenic microrganism compared to OMW, because higher amount of VFAs and CH4 were produced in AD of GP than OMW. In addition to these products, polyphenols were extracted by means of a solid phase extraction (SPE) procedure by another research group, and VFAs were utilised for biopolymers production, in particular polyhydroxyalkanoates (PHAs), by the same research group in which I was involved.

Development of an optimization model for biofuel facility size and location and a simulation model for design of a biofuel supply chain

To mitigate greenhouse gas (GHG) emissions and reduce U.S. dependence on imported oil, the United States (U.S.) is pursuing several options to create biofuels from renewable woody biomass (hereafter referred to as “biomass”). Because of the distributed nature of biomass feedstock, the cost and complexity of biomass recovery operations has significant challenges that hinder increased biomass utilization for energy production. To facilitate the exploration of a wide variety of conditions that promise profitable biomass utilization and tapping unused forest residues, it is proposed to develop biofuel supply chain models based on optimization and simulation approaches. The biofuel supply chain is structured around four components: biofuel facility locations and sizes, biomass harvesting/forwarding, transportation, and storage. A Geographic Information System (GIS) based approach is proposed as a first step for selecting potential facility locations for biofuel production from forest biomass based on a set of evaluation criteria, such as accessibility to biomass, railway/road transportation network, water body and workforce. The development of optimization and simulation models is also proposed. The results of the models will be used to determine (1) the number, location, and size of the biofuel facilities, and (2) the amounts of biomass to be transported between the harvesting areas and the biofuel facilities over a 20-year timeframe. The multi-criteria objective is to minimize the weighted sum of the delivered feedstock cost, energy consumption, and GHG emissions simultaneously. Finally, a series of sensitivity analyses will be conducted to identify the sensitivity of the decisions, such as the optimal site selected for the biofuel facility, to changes in influential parameters, such as biomass availability and transportation fuel price. Intellectual Merit The proposed research will facilitate the exploration of a wide variety of conditions that promise profitable biomass utilization in the renewable biofuel industry. The GIS-based facility location analysis considers a series of factors which have not been considered simultaneously in previous research. Location analysis is critical to the financial success of producing biofuel. The modeling of woody biomass supply chains using both optimization and simulation, combing with the GIS-based approach as a precursor, have not been done to date. The optimization and simulation models can help to ensure the economic and environmental viability and sustainability of the entire biofuel supply chain at both the strategic design level and the operational planning level. Broader Impacts The proposed models for biorefineries can be applied to other types of manufacturing or processing operations using biomass. This is because the biomass feedstock supply chain is similar, if not the same, for biorefineries, biomass fired or co-fired power plants, or torrefaction/pelletization operations. Additionally, the research results of this research will continue to be disseminated internationally through publications in journals, such as Biomass and Bioenergy, and Renewable Energy, and presentations at conferences, such as the 2011 Industrial Engineering Research Conference. For example, part of the research work related to biofuel facility identification has been published: Zhang, Johnson and Sutherland [2011] (see Appendix A). There will also be opportunities for the Michigan Tech campus community to learn about the research through the Sustainable Future Institute.

Producción de biogás a partir de biomasa de la microalga scenedesmus sp. procedente de diferentes procesos

En este trabajo de Tesis Doctoral se ha estudiado la posibilidad de emplear las microalgas, concretamente el género Scenedesmus, como sustrato para la producción de biogás mediante digestión anaerobia, así como los residuos que se producen como consecuencia de su utilización industrial para diferentes fines. La utilización de las microalgas para la producción de biocombustibles es un tema de gran actualidad científica, en el que residen muchas expectativas para la producción a gran escala de biocombustibles que supongan una alternativa real a los combustibles fósiles. Existen numerosas investigaciones sobre la conversión a biogás de las microalgas, sin embargo aún hay poco conocimiento sobre la utilización de la digestión anaerobia como tratamiento de residuos de microalgas en un concepto de biorrefinería. Residuos que pueden ser generados tras la extracción de compuestos de alto valor añadido (p. ej. aminoácidos) o tras la generación de otro biocombustible (p. ej. biodiésel). Es en este aspecto en el que esta Tesis Doctoral destaca en cuanto a originalidad e innovación, ya que se ha centrado principalmente en tres posibilidades: - Empleo de Scenedesmus sp. como cultivo energético para la producción de biogás. - Tratamiento de residuos de Scenedesmus sp. generados tras la extracción de aminoácidos en un concepto de biorrefinería. - Tratamiento de los residuos de Scenedesmus sp. generados tras la extracción de lípidos en un concepto de biorrefinería. Los resultados obtenidos demuestran que la microalga Scenedesmus como cultivo energético para producción de biogás no es viable salvo que se empleen pretratamientos que aumenten la biodegradabilidad o se realice codigestión con otro sustrato. En este último caso, la chumbera (Opuntia maxima Mill.) ha resultado ser un sustrato idóneo para la codigestión con microalgas, aumentando la producción de biogás y metano hasta niveles superiores a 600 y 300 L kgSV-1, respectivamente. Por otro lado, el tratamiento de residuos generados tras la extracción de aminoácidos mediante digestión anaerobia es prometedor. Se obtuvieron elevados rendimientos de biogás y metano en las condiciones de operación óptimas (409 y 292 L kgSV-1, respectivamente). Aparte de la generación energética por medio el metano, que podría emplearse en la propia biorrefinería o venderse a la red eléctrica o de gas natural, reciclando el digerido y el CO2 del biogás se podría llegar a ahorrar alrededor del 30% del fertilizante mineral y el 25% del CO2 necesarios para el cultivo de nueva biomasa. Por lo tanto, la digestión anaerobia de los residuos de microalgas en un concepto de biorrefinería tiene un gran potencial y podría contribuir en gran medida al desarrollo de esta industria. Por último, una primera aproximación al tratamiento de residuos generados tras la extracción de lípidos muestra que éstos pueden ser empleados para la producción de biogás, como monosustrato, o en codigestión con glicerina, ya que son fácilmente biodegradables y el rendimiento potencial de metano puede alcanzar 218 LCH4 kgSV-1 y 262 LCH4 kg SV-1 en monodigestión o en codigestión con glicerina, respectivamente. ABSTRACT This PhD thesis explores the possibility of using microalgae, specifically the strain Scenedesmus, as substrate for biogas production through anaerobic digestion, as well as the residues generated after its use in different industrial processes. The use of microalgae for biofuels production is an emerging scientific issue. The possibility of producing biofuels from microalgae as a real alternative for fossil fuels is raising high expectations. There are several research projects on the conversion of microalgae to biogas; however, there is little knowledge about using anaerobic digestion for treating microalgae residues in a biorefinery scheme. These residues could be generated after the extraction of high value compounds (e.g. amino acids) or after the production of another biofuel (e.g. biodiesel). It is in this area in which this PhD thesis stands in terms of originality and innovation, since it has focused primarily on three possibilities: - The use of Scenedesmus sp. as an energy crop for biogas production. - Treatment of amino acid extracted Scenedesmus residues generated in a biorefinery. - Treatment of lipid extracted Scenedesmus residues generated in a biorefinery. The results obtained in this work show that the use of Scenedesmus as energy crop for biogas production is not viable. The application of pretreatments to increase biodegradability or the codigestion of Scenedesmus biomass with other substrate can improve the digestion process. In this latter case, prickly pear (Opuntia maxima Mill.) is an ideal substrate for its codigestion with microalgae, increasing biogas and methane yields up to more than 600 and 300 L kgVS-1, respectively. On the other hand, the treatment of residues generated after amino acid extraction through anaerobic digestion is promising. High biogas and methane yields were obtained (409 y 292 L kgVS-1, respectively). Besides the energy produced through methane, which could be used in the biorefinery or be sold to the power or natural gas grids, by recycling the digestate and the CO2 30% of fertilizer needs and 25% of CO2 needs could be saved to grow new microalgae biomass. Therefore, the anaerobic digestion of microalgae residues generated in biorefineries is promising and it could play an important role in the development of this industry. Finally, a first approach to the treatment of residues generated after lipid extraction showed that these residues could be used for the production of biogas, since they are highly biodegradable. The potential methane yield could reach 218 LCH4 kgVS-1 when they are monodigested, whereas the potential methane yield reached 262 LCH4 kgVS-1 when residues were codigested with residual glycerin.

Bio-based chemicals from biorefining:carbohydrate conversion and utilisation

The quest for sustainable sources of fuels and chemicals to meet the demands of a rapidly rising global population represents one of this century's grand challenges. Biomass offers the most readily implemented, and low cost, solution for transportation fuels, and the only non-petroleum route to organic molecules for the manufacture of bulk, fine and speciality chemicals and polymers. Chemical processing of such biomass-derived building blocks requires catalysts compatible with hydrophilic, bulky substrates to facilitate the selective deoxygenation of highly functional bio-molecules to their target products. This chapter addresses the challenges associated with carbohydrate utilisation as a sustainable feedstock, highlighting innovations in catalyst and process design that are needed to deliver high-value chemicals from biomass-derived building blocks. © 2014 Woodhead Publishing Limited. All rights reserved.

Fast pyrolysis of biomass for energy and fuels

Bioenergy is now accepted as having the potential to provide the major part of the projected renewable energy provisions of the future as biofuels in the form of gas, liquid or solid fuels or electricity and heat. There are three main routes to providing these biofuels — thermal conversion, biological conversion and physical conversion — all of which employ a range of chemical reactor configurations and process designs. This paper focuses on fast pyrolysis from which the liquid, often referred to as bio-oil, can be used on-site or stored or transported to centralised and/or remote user facilities for utilisation for example as a fuel, or further processing to biofuels and/or chemicals. This offers the potential for system optimisation, much greater economies of scale and exploitation of the concepts of biorefineries. The technology of fast pyrolysis is described, particularly the reactors that have been developed to provide the necessary conditions to optimise performance. The primary liquid product is characterised, as well as the secondary products of electricity and/or heat, liquid fuels and a considerable number of chemicals. The main technical and non-technical barriers to the market deployment of the various technologies are identified and briefly discussed.

Ultraäänen käyttö ligniinin ja hemiselluloosan ertuksessa puu-uutteesta

Puusta valmistetussa puu-uutteessa on puun polymeerejä, ligniiniä ja hemiselluloosaa, joiden käyttöä halutaan lisätä biojalostamoissa. Polymeerit tulisi erottaa mahdollisimman puhtaasti jatkojalostusta varten. Erotus voidaan tehdä ultrasuodatuksella. Puu-uutetta pitää kuitenkin esikäsitellä, sillä polymeerit ovat lähes samankokoisia. Ultraäänikäsittelyn on osoitettu kasvattavan ligniinin moolimassaa, jolloin myös erotus parantuisi. Ultraäänikäsittely on aikaisemmin käytettyihin esikäsittelymenetelmiin verrattuna ympäristöystävällisempi, sillä sen käytössä ei tarvita erillisiä kemikaaleja. Tämän työn tavoitteena oli selvittää, kuinka ultraäänikäsittely vaikuttaa ligniinin ja hemiselluloosan erotukseen PHWE-puu-uutteesta. Näytteen pH säädettiin emäksiseksi, näyte ultraäänikäsiteltiin eri koeolosuhteissa ja ultrasuodatettiin. Ultraäänikäsiteltyä näytettä verrattiin käsittelemättömään referenssinäytteeseen. Näytteet analysoitiin UV- ja TOC-analyyseillä konsentraattien ligniini- ja hiilipitoisuuksien selvittämiseksi. Lisäksi tarkasteltiin suodatusprosessin parametreja. Tulosten perusteella ultraäänikäsittely paransi ligniinin ja hemiselluloosan erotusta erilleen. Erotus parani eniten pH 12 -näytteessä, joka ultraäänikäsiteltiin 65 °C lämpötilassa, 45 minuutin ajan laiteteholla 175 W.