Ciencias Exactas y Ciencias de la Salud
Permanent URI for this collectionhttps://hdl.handle.net/11285/551039
Pertenecen a esta colección Tesis y Trabajos de grado de las Maestrías correspondientes a las Escuelas de Ingeniería y Ciencias así como a Medicina y Ciencias de la Salud.
Browse
Search Results
- Microalgae-based livestock wastewater treatment and resource recovery: a circular bioeconomy approach(Instituto Tecnológico y de Estudios Superiores de Monterrey, 2021-12-07) López Sánchez, Anaid; Carrillo Nieves, Danay; emijzarate; Orozco Nunnelly, Danielle A.; Senés Guerrero, Carolina; Aguilar Juárez, Óscar; Escuela de Ingeniería y Ciencias; Campus Monterrey; Gradilla Hernández, Misael SebastiánThe livestock industry is a sector of great relevance worldwide. This sector accounts for 1.4% of the world's Gross Domestic Product (GDP) and is a source of livelihood for more than 1.3 billion people. Furthermore, thirty-nine percent of the worldwide protein demand is covered by this sector. However, this activity is one of the top polluting industries, accounting for 14% of the greenhouse gasses (GHG) originated from anthropogenic sources. Additionally, the livestock sector is the largest land user on earth, using 70% of the total agricultural land and 30% of Earth’s land surface. One-third of the global cereal production is destinated for animal feed, of which some nutrients are retained by the animals and the rest is released to the environment without previous treatment, resulting in soil degradation, water and air pollution and, consequently, serious human health impacts. Circular bioeconomy (CBE) has emerged as a potential driver towards the sustainability of livestock production systems. One of the main objectives of the CBE model within the livestock industry is the minimization of the usage of raw material resources through the recycling, reuse, and revalorization of waste and wastewater. Microalgae-based wastewater treatment (MbWT) is a potential solution aligned with the CBE principles, in which the nutrients contained in the livestock wastewater (LW) are recovered and transformed into high value-added products with a wide range of industrial applications. The overall performance of MbWT (i.e., nutrient removal efficiencies and biomass production) is highly dependent on a wide range of factors, such as the microalgal strain and the composition of the wastewater. However, most of the existing studies that implemented MbWT have focused on a single LW type. Therefore, the main objective of this thesis is to treat a mixed effluent composed of the most common ADLW (from cattle, swine, and poultry), to understand the effects of the mixture of all three types of LW on cell growth and pollutant removal efficiencies of microalgal cultures (Chlorella vulgaris, Haematoccocus pluvialis and Chlamydomonas spp.). Through an evaluation of the mixture design, the optimal fraction of these different types of effluents (ADCW, ADSW, and ADPW) was analyzed to obtain maximum microalgal biomass productivity and 7 pollutant removal rates (COD, TN and TP). Furthermore, these microalgae were tested in all possible combinations of mono-, bi-, and tri-cultures. The first chapter of the present thesis consists of a thorough review of the literature to address the most significant factors affecting nutrient removal and biomass productivity in MbWT, including: (i) microbiological aspects, such as the microalgal strain used for MbWT and the interactions between microbial populations; (ii) physical parameters, such as temperature, light intensity and photoperiods; and (iii) chemical parameters, such as the C/N ratio, pH and the presence of inhibitory compounds. Additionally, different strategies to enhance nutrient removal and biomass productivity, such as acclimation, UV mutagenesis, multiple microalgae culture stages (including monocultures and multicultures) are discussed. The second chapter of this thesis presents the first study of MbWT using anaerobically digested swine, poultry and cattle wastewater (ADSW, ADPW and ADCW) mixtures. A centroid mixture design was used to determine the optimal mixture to promote higher cell concentrations and pollutant removal efficiencies of the microalgae Chlorella vulgaris, Haematococcus pluvialis and Chlamydomonas spp. cultured as mono-, bi-, and tri-cultures. Additionally, A redundancy analysis was performed to analyze the correlation between microalgal cultures and the removal efficiencies of the digestate pollutants. The results herein show that C. vulgaris as a monoculture in a digestate mixture of 0.125:0.4375:0.4375 (ADSW:ADPW:ADCW) resulted in cell growth of 3.61×107 ± 2.81x106 cell mL-1, a total nitrogen removal of 85%±2%, a total phosphorus removal of 66%±3% and a chemical oxygen demand removal of 44%±7%. The specific composition of the effluents plays a key role in microalgal performance due to their respective nitrogen and phosphorus content. Furthermore, this study suggests that a mixture of the three most common digestates generated by livestock farms offers a promising alternative for the treatment and revalorization of LW, by taking advantage of the unique composition that each digestate possesses. Further studies are warranted to gain a deeper understanding of the interspecific microalgal interactions occurring in mixed cultures that may enhance or hinder the performance of MbWT.
- Development of circular bioeconomy strategies for the integrated management of tequila vinasses(Instituto Tecnológico y de Estudios Superiores de Monterrey) Díaz-Vázquez, Diego; CARRILLO NIEVES, DANAY; 491504; Gradilla Hernandez, Misael Sebastián; Carrillo Nieves, Danay; Orozco Nunnelly, Danielle A.; Jauregui Jauregui, Jesus Antonio; Aguilar Juárez, Oscar; Senes Guerrero, CarolinaThe agro-food industry is one of the largest productive sectors globally, by volume and economic relevance. Food demand is expected to keep increasing with the global population, increasing environmental strains by raw resource consumption and intensive waste generation. The circular bioeconomy model aims to reduce resource depletion and waste generation from bio-based production systems, such as the agro-food industry, by the circularization of material and energy flows into productive processes. The aim of the present thesis is to evaluate the implementation of novel circular bioeconomy approaches for the tequila industry, focusing on the integral management of tequila vinasses (TV). The first part of the present thesis presents an integrated approach for the assessment of environmental sustainability in agro-industrial waste management practices. This encompasses an extensive physicochemical characterization of spatially distributed vinasses samples within the state of Jalisco, the implementation of a geographic information system to characterize the spatial distribution of the waste production and the implementation of mathematical models to evaluate management scenarios in terms of their environmental impacts and their potential for low-value material recovery. The second part of the thesis presents a circular bioeconomy alternative for the simultaneous treatment and revalorization of TV into animal feed supplements by the culture of fodder yeast species (Candida utilis, Kluyveromyces marxianus y Rhodotorula mucilaginosa). Culture treatments (monocultures and mixed cultures were evaluated for the removal of pollutants (Chemical oxygen demand (COD), total nitrogen (TN) , and total phosphorus(TP))as well as protein production. Additionally, TV concentration was evaluated as an additional factor of the experimental design. A weighted response index was used to evaluate the treatments and the culture treatments that displayed the best performance were selected for benchtop-scale escalation. Benchtop-scale cultures were monitored every 8 hours for a 48-hour period, during which 6 parameters were determined (COD, TN, TP, viable biomass, protein, reducing sugar concentrations). For the benchtop-scale, the kinetic parameters in a mass balance model based on the Monod equation were determined for a mass balance model using a differential neural network and an optimization algorithm. The biomass obtained from the benchtop-scale cultures was spray dried and analyzed to determine its amino acid composition and evaluate its applicability as an animal feed supplement. Further research is required to allow the escalation of the proposed biorefinery process from lab-scale to pilot-scale to guarantee its economic and technical feasibility. The results obtained in the present work have shown that the implementation of circular bioeconomy models has the potential to significatively reduce environmental strains caused by linear agro-food industrial systems and can help achieve local and international commitments toward sustainability. The integration of both low-value and high-value biological recovery strategies on the local and regional context could significatively reduce organic and nutrient pollution by its recovery either as low-value components (biogas, fertilizers, and sludge) or as high-value products (protein and biomass for animal feed supplementation) while increasing the economic viability of waste management through the commercialization of recovered byproducts. The reduction of treatment costs and the new economic incentives offered by the revalorization of agro-food waste can be beneficial for small and micro producers, who lack the capital required for higher infrastructure investments. This study lays the foundation for policy makers to establish guidelines, programs, incentives, and regulations to guide the tequila production sector towards the development of circular economic models based on scientifically sound methodologies