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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Making biodiesel from spent coffee grounds through in situ transesterification

Liu, Yang 16 October 2015 (has links)
No description available.
2

Multivalorizaiton of beverage industry waste streams for the development of bioplastics and food ingredients

Williamson, Kathryn January 2021 (has links)
No description available.
3

Zero Waste Utilization of Spent Coffee Grounds (SCGs) and the Feasibility Study of Heavy Metal Removal from the Aqueous Phase with SCG Biochar

Srivastava, Suhas January 2020 (has links)
No description available.
4

Minimização de resíduos do processamento do café solúvel através do reaproveitamento da borra para extração de óleo utilizando solvente renovável / Minimization of residues of soluble coffee processing by reuse of spent coffee grounds in oil extraction with a renewable solvent

Toda, Tatiane Akemi 04 March 2016 (has links)
O principal resíduo da indústria de café solúvel é a borra de café, gerada após a extração de sólidos solúveis com água, sendo usualmente queimada em caldeiras para geração de energia para a própria indústria. Entretanto, este co-produto pode conter de 15 a 20 % de óleo, componente de grande interesse na indústria alimentícia. Em paralelo, na indústria de produção de óleos vegetais o solvente frequentemente utilizado é o hexano. Contudo, por este ser um derivado de combustíveis fósseis, alternativas para sua substituição por solventes mais amigáveis ao meio ambiente, que podem ser obtidos por via biotecnológica, estão sendo estudadas. Deste modo, o objetivo principal desta dissertação de mestrado foi a viabilização técnica do emprego de solventes alcoólicos no processo de extração de óleo de borra de café proveniente da indústria de processamento de café solúvel. Foram realizadas extrações sólido-líquido em um estágio para estudar a influência das variáveis de processo temperatura (60 a 90 °C), tipo de solvente (etanol, ET ou isopropanol, IPA) e a hidratação do solvente (absoluto ou azeotrópico) nas características das fases extrato e rafinado, em termos de rendimento de extração de óleo, de ácidos clorogênicos (ACG), de carboidratos totais, teor de proteínas e índice de solubilidade de nitrogênio (ISN) da fase rafinado. Pré-tratamento enzimático ao processo de extração também foi realizado para investigar a sua atuação sobre o rendimento de extração de óleo e ACG, além do ISN das fases rafinado obtidas na temperatura de 70 °C. De forma geral, pode-se inferir que a temperatura favorece a extração de compostos lipídicos, mas a hidratação do solvente prejudica a extração destes compostos pelo aumento da polaridade do solvente. Do mesmo modo, como o ET é mais polar que o IPA, o primeiro solvente proporcionou a obtenção de menores rendimentos de extração de óleo. A temperatura de processo também influenciou a extração de ACG, a qual foi beneficiada a temperaturas mais baixas pelo aumento da polaridade dos solventes utilizados. De tal forma, que a 60 °C, nos experimentos utilizando etanol azeotrópico obteve-se os menores rendimentos de extração de óleo, porém maior rendimento de extração de ACG. O pré-tratamento enzimático apresentou diferenças significativas nas características das fases extrato e rafinado. No entanto, somente os experimentos com etanol absoluto resultaram em rendimentos de extração de óleo economicamente viáveis. De fato, será relevante um estudo mais aprofundado das variáveis de pré-tratamento enzimático para obter resultados mais expressivos em relação à extração de compostos lipídicos. Diante dos dados experimentais obtidos, conclui-se que é tecnicamente viável o emprego de solventes alcoólicos no processo de extração de óleo de borra de café. Entretanto, nota-se que as condições de processo devem ser avaliadas minuciosamente com o objetivo de se obter altos rendimentos de extração de óleo com maior teor de ACG. / Spent coffee grounds are the main residues of the soluble coffee industry, which are generated after the extraction of soluble solids with water. They are generally burned in boilers to generate energy for the coffee industry. However, this residue may contain 15 to 20 % oil, a component of interest to the food industry. Hexane is the most common solvent used in the vegetable oil industry; however, as it is a fossil fuel byproduct, biotechnology alternatives that replace it by more environmental-friendly solvents are being studied. Therefore, the main objective of this study was to determine technical viability of alcoholic solvents in oil extraction of spent coffee grounds. Solid-liquid extractions were carried out in one stage in order to analyzed the influence of the variables of the process (temperature, 60 to 90 °C; type of solvent, ethanol, ET or isopropanol, IPA; and solvent hydration level, absolute or azeotropic degree) in the characteristics of extract and raffinate phases, in terms of yield of oil extraction, chlorogenic acids (CGA), total carbohydrates, protein content, and nitrogen solubility index (NSI) of the raffinate phase. Enzymatic pre-treatment in the extraction process was also carried out to assess its effect on the oil and CGA yields, as well as NSI in the raffinate phase obtained at 70 °C. In general, it could be inferred that temperature favored lipid extraction, but solvent hydration level negatively affected extraction due to the increased polarity of the solvent. Similarly, as ET is more polar than IPA, the former solvent enabled lower yield of oil. The temperature of the process also influenced CGA extraction, which was favored by lower temperatures and increased solvent polarity. Therefore, at 60 °C, in the trials using azeotropic ethanol, oil extraction yield was lower, and CGA yield was greater. Enzymatic pre-treatment showed significant differences in the characteristics of the extract and raffinate phases. However, only the trials with absolute ethanol led to economically viable oil yields. In fact, further studies on pre-treatment variables of the enzymatic treatment should be carried out for more relevant results in relation to lipid compound extraction. Given the experimental data obtained here, it was concluded that the use of alcoholic solvents in oil extraction of spent coffee grounds is technically viable. However, the conditions of the process should be carefully analyzed for high yields of oil with greater levels of CGA to be obtained.
5

EVALUATING SOIL PHYSICAL AND CHEMICAL PROPERTIES FOLLOWING ADDITION OF NON-COMPOSTED SPENT COFFEE AND TEA FOR ATHLETIC FIELDS

Zhou, Shuang 01 January 2017 (has links)
Physical and chemical properties of non-composted spent coffee (CF) and tea (T) suggest they may have applications as soil amendments for improving poor soils. Studies were conducted to determine 1) the effect of amendments on grass growth and soil properties, 2) the effect of incorporation versus surface application of amendments on soil properties, and 3) the effect of amendment application frequency on grass growth and soil properties. In the first study, amendments were mixed with sand and planted to bermudagrass. Treatments included CF, T, and peat moss (PM) mixed with sand, and 100% sand as a control. In the second study, amendments were topdressed onto a sand base with different timings. Pots were either aerified or not. Treatments included T, CF, PM, and a control. Nutrient contents and soil CEC and OM under CF and T treatments were equivalent to or greater than PM treatments. Tea showed comparable grass cover to the PM treatment, while CF showed an inhibitory effect to grass growth in the first year of the study. Aerification showed no benefit. Additionally, a field study was conducted to evaluate CF and T on surface hardness, VWC, and quality after trafficking. Differences were not observed among treatments.
6

Minimização de resíduos do processamento do café solúvel através do reaproveitamento da borra para extração de óleo utilizando solvente renovável / Minimization of residues of soluble coffee processing by reuse of spent coffee grounds in oil extraction with a renewable solvent

Tatiane Akemi Toda 04 March 2016 (has links)
O principal resíduo da indústria de café solúvel é a borra de café, gerada após a extração de sólidos solúveis com água, sendo usualmente queimada em caldeiras para geração de energia para a própria indústria. Entretanto, este co-produto pode conter de 15 a 20 % de óleo, componente de grande interesse na indústria alimentícia. Em paralelo, na indústria de produção de óleos vegetais o solvente frequentemente utilizado é o hexano. Contudo, por este ser um derivado de combustíveis fósseis, alternativas para sua substituição por solventes mais amigáveis ao meio ambiente, que podem ser obtidos por via biotecnológica, estão sendo estudadas. Deste modo, o objetivo principal desta dissertação de mestrado foi a viabilização técnica do emprego de solventes alcoólicos no processo de extração de óleo de borra de café proveniente da indústria de processamento de café solúvel. Foram realizadas extrações sólido-líquido em um estágio para estudar a influência das variáveis de processo temperatura (60 a 90 °C), tipo de solvente (etanol, ET ou isopropanol, IPA) e a hidratação do solvente (absoluto ou azeotrópico) nas características das fases extrato e rafinado, em termos de rendimento de extração de óleo, de ácidos clorogênicos (ACG), de carboidratos totais, teor de proteínas e índice de solubilidade de nitrogênio (ISN) da fase rafinado. Pré-tratamento enzimático ao processo de extração também foi realizado para investigar a sua atuação sobre o rendimento de extração de óleo e ACG, além do ISN das fases rafinado obtidas na temperatura de 70 °C. De forma geral, pode-se inferir que a temperatura favorece a extração de compostos lipídicos, mas a hidratação do solvente prejudica a extração destes compostos pelo aumento da polaridade do solvente. Do mesmo modo, como o ET é mais polar que o IPA, o primeiro solvente proporcionou a obtenção de menores rendimentos de extração de óleo. A temperatura de processo também influenciou a extração de ACG, a qual foi beneficiada a temperaturas mais baixas pelo aumento da polaridade dos solventes utilizados. De tal forma, que a 60 °C, nos experimentos utilizando etanol azeotrópico obteve-se os menores rendimentos de extração de óleo, porém maior rendimento de extração de ACG. O pré-tratamento enzimático apresentou diferenças significativas nas características das fases extrato e rafinado. No entanto, somente os experimentos com etanol absoluto resultaram em rendimentos de extração de óleo economicamente viáveis. De fato, será relevante um estudo mais aprofundado das variáveis de pré-tratamento enzimático para obter resultados mais expressivos em relação à extração de compostos lipídicos. Diante dos dados experimentais obtidos, conclui-se que é tecnicamente viável o emprego de solventes alcoólicos no processo de extração de óleo de borra de café. Entretanto, nota-se que as condições de processo devem ser avaliadas minuciosamente com o objetivo de se obter altos rendimentos de extração de óleo com maior teor de ACG. / Spent coffee grounds are the main residues of the soluble coffee industry, which are generated after the extraction of soluble solids with water. They are generally burned in boilers to generate energy for the coffee industry. However, this residue may contain 15 to 20 % oil, a component of interest to the food industry. Hexane is the most common solvent used in the vegetable oil industry; however, as it is a fossil fuel byproduct, biotechnology alternatives that replace it by more environmental-friendly solvents are being studied. Therefore, the main objective of this study was to determine technical viability of alcoholic solvents in oil extraction of spent coffee grounds. Solid-liquid extractions were carried out in one stage in order to analyzed the influence of the variables of the process (temperature, 60 to 90 °C; type of solvent, ethanol, ET or isopropanol, IPA; and solvent hydration level, absolute or azeotropic degree) in the characteristics of extract and raffinate phases, in terms of yield of oil extraction, chlorogenic acids (CGA), total carbohydrates, protein content, and nitrogen solubility index (NSI) of the raffinate phase. Enzymatic pre-treatment in the extraction process was also carried out to assess its effect on the oil and CGA yields, as well as NSI in the raffinate phase obtained at 70 °C. In general, it could be inferred that temperature favored lipid extraction, but solvent hydration level negatively affected extraction due to the increased polarity of the solvent. Similarly, as ET is more polar than IPA, the former solvent enabled lower yield of oil. The temperature of the process also influenced CGA extraction, which was favored by lower temperatures and increased solvent polarity. Therefore, at 60 °C, in the trials using azeotropic ethanol, oil extraction yield was lower, and CGA yield was greater. Enzymatic pre-treatment showed significant differences in the characteristics of the extract and raffinate phases. However, only the trials with absolute ethanol led to economically viable oil yields. In fact, further studies on pre-treatment variables of the enzymatic treatment should be carried out for more relevant results in relation to lipid compound extraction. Given the experimental data obtained here, it was concluded that the use of alcoholic solvents in oil extraction of spent coffee grounds is technically viable. However, the conditions of the process should be carefully analyzed for high yields of oil with greater levels of CGA to be obtained.
7

Modelování a kultivace vybraných mikroorganismů na hydrolyzátech odpadních substrátů / Modeling and cultivation of some microorganisms on waste substrate hydrolysates

Kecskésová, Viktória January 2018 (has links)
The aim of Diploma thesis was the cultivation of microorganisms Lactobacillus plantarum CCM 7039 and Bacillus coagulans CCM 2658 on hydrolysed spent coffee grounds, production of lactid acid and modelling of these processes to find out more detailed characteristics. First, both microorganisms were cultivated in Erlenmeyer flasks on spent coffee grounds hydrolysate containing lipids and processed by extraction of lipids, e.g. lipid-free. The effect of nitrogen source and inoculation medium were monitored in the course of cultivation. The optimal conditions found were used for subsequent fermentation in bioreactors. Further, microorganisms were cultivated in the Erlenmeyer flasks in the media with individual carbohydrates typical for hydrolysed spent coffee grounds to determine its ability to utilize these carbohydrates. By fermentation in the bioreactors, the yield of lactic acid from carbohydrates was 97 % in Lactobacillus plantarum and 99 % in Bacillus coagulans, respectively. Models for growth and productivity of microorganisms were processed in MATLAB using logistic, generalized logistic and Monod functions. In general, the best data fit was achieved using a logistic function.
8

Optimalizace kultivace karotenogenních kvasinek na směsných odpadních substrátech / Optimization of cultivation of carotenogenic yeasts on mixed waste substrates

Holub, Jiří January 2020 (has links)
The master thesis addresses the issue of cultivation of selected strains of carotenogenic yeasts on waste materials of the food industry using a laboratory bioreactor. Carotenogenic yeasts are able to produce highly valuable metabolites during cultivation, which are located predominantly in the lipid part of the cells. Particularly, they are carotenoids, ergosterol, coenzyme Q and fatty acids. The thesis is divided into two main parts, the theoretical part and the practical part. The theoretical part describes individual yeast strains, types of waste materials, produced metabolites and methods of their analysis. The experimental part deals with the processing of waste materials of the food industry, specifically animal fat, whey and spent coffee grounds into the form of substrates usable as nutrition sources for yeast cultivation. Furthermore, cultivations focused on the recovery of the monitored metabolites and their analysis by using HPLC/PDA and GC/FID assemblies were studied as well. The yeast strains Rhodotorula mucilaginosa (CCY 19-4-6), Rhodotorula kratochvilae (CCY 20-2-26), Rhodosporidium toruloides (CCY 062-002-001), Sporidiobolus pararoseus (CCY 19-9-6) a Cystofilobasidium macerans (CCY 10-1-2) were used in this work. As one of the best producing strains Sporidiobolus pararoseus (CCY 19-9-6) was found, which achieved very high productions of carotenoids, coenzyme Q and ergosterol.
9

Analýza energetického využití kávových pelet / Analysis of Enery Using of Coffee Pellets

Sedláček, Daniel January 2016 (has links)
The aim of my thesis was to develop a comprehensive study on the energy use of the coffee waste called spent coffee grounds. The study conducted a complete fuel analysis, TGA analysis, experimental drying and pelletization, combustion tests and basic economic evaluation.
10

Valorising spent coffee grounds : An assessment of possibilities in the municipality of Stockholm / Värdesättning av kaffesump : En bedömning av möjligheter i Stockholm stad

Westling, Emma January 2023 (has links)
Circular economy is an economic model that is gaining more and more attention, themodel aims to close production chains by recirculate waste into the system as newraw material. Spent coffee grounds are a waste that has great potential to becomenew products since the spent coffee ground contains many valuable substances suchas polysaccharides, polyphenols, and lipids. Swedes are the sixth largest coffeeconsumers per capita in the world, which means that large quantities of coffeegrounds are produced in the country. Therefore, the purpose of this report is toinvestigate possible ways to valorize spent coffee grounds in the municipality ofStockholm, as an alternative to the treatment processes that exist today. Toinvestigate this, the main methods have been a literature review, a field study andeconomic analyses based on existing data. The results show that from 5 large coffee-shop chains in the municipality of Stockholm, approximately 138,477 kg of coffeegrounds can be collected each year. Furthermore, it shows that five differentmethods for extracting polysaccharides, polyphenols, biochar, oil, and protein fromspent coffee grounds have been effective and that these substances and products canbe used in, for example, the food industry, in cosmetics, as plastics and asadsorbents. The economic assessment shows that biochar, polyphenols, and oil arethe compounds and products that are economically profitable to extract, and theycan give a maximum profit of SEK 482.28/kg of spent coffee grounds. The resultsare consistent with previous research on the subject, but there are someuncertainties in the exact figures as there is a lack of economic analyses for spentcoffee grounds in the previous research. However, the results show great potentialfor spent coffee grounds in a circular economy, but further research is required toensure the economic gain. In addition, analyses need to be done on the ecologicalsustainability and more studies need to be done on coffee grounds in Sweden tovalidate the results. / Cirkulär ekonomi är en ekonomisk modell som får mer och mer uppmärksamhet,modellen syftar till att sluta produktionskedjor genom att återinföra avfall som nyttråmaterial. Kaffesump är ett avfall som har stor potential att bli nya produkter pågrund av att sumpen innehåller många värdefulla ämnen som polysackarider,polyfenoler och lipider. Svenskar är de sjätte största kaffekonsumenterna per capitai världen vilket gör att stora mängder kaffesump produceras i landet. Därför är syftetmed denna rapport att undersöka möjliga vägar för att värdesätta kaffesump iStockholms stad, som alternativ till de behandlingsprocesser som finns idag. För attundersöka detta har de huvudsakliga metoderna varit en litteraturstudie, enfältstudie och ekonomiska analyser baserade på befintliga data. Resultaten visar attfrån 5 stora kafékedjor i Stockholms stad kan cirka 138 477 kg kaffesump samlas invarje år. Vidare visar det att fem olika metoder för att utvinna polysackarider,polyfenoler, biokol, olja och protein ur kaffesump har varit effektiva och att dessaämnen och produkter kan användas inom exempelvis livsmedelsindustrin, ikosmetika, som plast och som adsorberande material. Den ekonomiskabedömningen visar att biokol, polyfenoler och olja är de ämnen och produkter somär ekonomiskt lönsamma att utvinna och de kan ge en maximal vinst på 482,28kr/kg kaffesump. Resultaten stämmer överens med tidigare forskning på ämnet mendet finns vissa osäkerheter i de exakta siffrorna då det saknas ekonomiska analyserför kaffesump i den tidigare forskningen. Resultaten visar dock på stor potential förkaffesump i en cirkulär ekonomi men vidare forskning krävs för att säkerställa denekonomiska vinningen. Dessutom behöver analyser göras på den ekologiskahållbarheten och fler studier behöver göras på kaffesump i Sverige för att valideraresultaten.

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