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Procesos Ambientales - GIPROAM

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Cultivation of Chlorella sp. for biodiesel production using two farming wastewaters in eastern Colombia

Urbina-Suarez, Nestor Andres | 2021-08-01

The production of biofuels using wastewater as a microalgae culture medium is a little explored technology, but with potential for success. In order to contribute to the knowledge of these technologies and their technical feasibility for microalgae growth, in this work the Chlorella sp. strain was cultivated in two types of effluents generated in an experimental farm located in eastern Colombia, before and after a biological treatment process. The consumption of the main nutrients that regulate growth and lipid production was evaluated, in order to extract, quantify, characterize and convert them into biodiesel. The results showed that Chlorella sp. growth and lipid production is more favourable in R2 medium of treated water than in R1 medium of raw water, mainly due to phosphorus limitation and higher N-NO3 concentration in R2 compared to R1. In the R2 medium culture, a percentage of 42.54% of long-chain fatty acids was found, which is necessary to obtain a high quality biodiesel. Finally, the best transesterification experiment allowed reaching a fatty acid methyl esters (FAME) percentage of 90.1 ± 2.7%. In general, the results demonstrated the potential viability of using the wastewater generated in the San Pablo farm to produce biomass with lipid content to obtain biodiesel, finding that where the concentration of nutrients, mainly nitrogen, has a great influence on the microalgal metabolism for lipid accumulation.

Different effect of nitrogen sources in autotrophic and mixotrophic culture of Scenedesmus spfor biomass and carotenoids production using acidic coal mine drainage effluents

Urbina-Suarez, Nestor Andres | 2021-10-30

In the present study, the conditions for an autotrophic and mixotrophic culture of Scenedesmus sp were established. Effluents from acidic coal mine drains were used to study biomass and carotenoid production, both under autotrophic and mixotrophic conditions in relation to the effect of different sources of nitrogen: sodium nitrate, urea and ammonium phosphate. Pollutant removal was determined, such as COD, TOC, heavy metals, ions and total suspended solids. Batch cultures lasted nine days and biomass production, carotenoids and pollutant removal were compared in each condition. The highest biomass concentration reached was 1.2 g/L in the mixotrophic culture with urea, followed by the culture with sodium nitrate of 0.9 g/L in a C/N ratio of 6:1. The highest carotenoid specific concentration was reached in the mixotrophic culture with sodium nitrate, 19.43 mg carotenoids /g biomass. The culture with ammonium phosphate was found to be inhibitory for the growth of the microalgae with the lowest results of all the parameters except for the autotrophic culture where the concentration of carotenoids was very similar to those reached with sodium nitrate and urea. Finally, the mixotrophic culture with urea presented the highest removal percentages, being 86.97% for total iron, 58.29% for chlorides and 92.5% for COD.

Procesos Avanzados De Oxidación Basados En Ozono Como Alternativa De Tratamiento Para Lixiviados De Rellenos Sanitarios

Becerra Moreno, Dorance | 2021-09-07

Los procesos basados en ozono hacen parte de los Procesos Avanzados de Oxidación que se han aplicado sobre los lixiviados de rellenos sanitarios. Las características altamente tóxicas de los lixiviados de rellenos sanitarios, pueden reducirse por medio de los procesos basados en ozono, los cuales han demostrado alcanzar altas remociones de contaminantes, en especial, de compuestos orgánicos recalcitrantes. En esta revisión se compila información reciente (2015 a 2021) referente a los procesos basados en ozono, donde se ha estudiado la eficacia como tratamiento, se analiza las condiciones óptimas de acuerdo al tipo de lixiviado y al método de tratamiento a emplear. Se identifica la tendencia de implementación como pretratamiento y postratamiento acoplado a procesos convencionales.

Análisis De Las Aplicaciones De La Microalga Botryococcus Braunii En Procesos Industriales

Carrascal Rivera, Derly Darleyn | 2021-09-07

Las microalgas y cianobacterias son la nueva plataforma biotecnológica par la producción de diversos metabolitos de interés industrial como carbohidratos, proteínas, lípidos, carotenoides e incluso metabolitos menos comunes como lo son los hidrocarburos y los exopolisacaridos. Una de las especies con la capacidad de producir un amplio espectro de metabolitos es Botryococcus braunii. Esta alga verde colonial posee la peculiaridad de sintetizar hidrocarburos, Exopolisacáridos y otros metabolitos. La presente contribución presenta un panorama bibliométrico de la investigación mundial sobre la producción de B. braunii y sus principales metabolitos de interés para procesos industriales. Los datos de publicaciones científicas durante los últimos 21 años (2000-2021) se obtuvieron de la base de datos SCOPUS© y se filtraron mediante una estrategia de búsqueda sistemática. A partir del análisis se obtuvo un total de 675 documentos científicos enfocados en el aislamiento, producción y mejoramiento de cepas pertenecientes a la especie Botryococcus braunii. De acuerdo con la información obtenida la mayor cantidad de trabajos publicados se han enfocado en la producción y mejoramiento de hidrocarburos tanto para la obtención de biocombustibles. Los principales países que mas han aportado a la investigación de esta especie son Estados Unidos, Japón, China e India; Sin embargo países con alta concentración de biodiversidad como Colombia presentan pocos trabajos con cepas aisladas dentro del territorio nacional. Este análisis bibliométrico permite evidenciar el alto grado de desarrollo obtenido en los últimos 20 años para generar plataformas biotecnológicas para la obtención de. nuevas materias primas para diferentes sectores industriales.

Removal of Nutrients and Pesticides from Agricultural Runoff Using Microalgae and Cyanobacteria

Castellanos Estupiñan, Miguel A. | 2022-02-12

The use of pesticides in agriculture has ensured the production of different crops. However, pesticides have become an emerging public health problem for Latin American countries due to their excessive use, inadequate application, toxic characteristics, and minimal residue control. The current project evaluates the ability of two strains of algae (Chlorella and Scenedesmus sp.) and one cyanobacteria (Hapalosyphon sp.) to remove excess pesticides and other nutrients present in runoff water from rice production. Different concentrations of wastewater and carbon sources (Na2CO3 and NaHCO3 ) were evaluated. According to the results, all three strains can be grown in wastewater without dilution (100%), with a biomass concentration comparable to a synthetic medium. All three strains significantly reduced the concentration of NO3 and PO4 (95 and 85%, respectively), with no difference between Na2CO3 or NaHCO3 . Finally, Chlorella sp. obtained the highest removal efficiency of the pesticide (Chlorpyrifos), followed by Scenedesmus and Hapalosyphon sp. (100, 75, and 50%, respectively). This work shows that it is possible to use this type of waste as an alternative source of nutrients to obtain biomass and metabolites of interest, such as lipids and carbohydrates, to produce biofuels.

Air quality in the colombian andean region: behavior of tropospheric no2 from satellite data

Oviedo Sanabria, Carlos Humberto | 2023-07

This study focuses on the analysis of air quality behavior, with a specific focus on tropospheric nitrogen dioxide as a parameter of interest in the Andean region of Colombia. To achieve this analysis, 12 cities in the country were taken as reference points. By processing more than 250,000 images, crucial data were extracted to evaluate the behavior of air quality during the period between 2019 and 2022. The results reveal a counterintuitive behavior, as the city with the most inhabitants is not the one with the highest pollution levels.

Huella hídricaverdeyazulde la producciónde cañadeazúcarorgánicaen lazona centrodelValle delCauca

Ramirez Rios, Luisa Fernanda | 2022-05-26

The estimation of the green and blue water footprint in the production of organic sugarcane (Saccharum officinarum)wasobtainedforaplantingareaof621.5hectaresintheAmaimeriverbasininValledelCauca,Colombia.Thestudyrepresents the first approximation in the quantification of the theoretical amount of water required by growers toproduce sugarcane under organic planting conditions, based on the methodological guidelines proposed in the WaterFootprintEvaluationManualoftheauthorsArjenandHoekstraetal,(2011), andthecomputerprogramCROPWAT8.0 of the Food and Agriculture Organization of the United Nations (FAO). The results for the green water footprintyielded an indicator of 117.07 m3/t, and 37.44 m3/t for the blue water footprint, for a total water footprint of 154.51m3/t. The obtained data were analyzed comparatively with results from the literature about the traditional cultivationof sugarcane in Colombia, and international references for the same crop, so that the cultivation of organic sugarcanecould present competitive advantages in environmental terms, associated with the use of water resources and contextconditions. Moreover, it is necessary to deepen the analysis of the gray water footprint and analyses that involvecultural,social,scientific,economic,biophysical,and politicalaspectsthatleadtotheintegralityoftheindicator.

Validation of the modified Témez rational model in the watersheds of Norte de Santander, Colombia

calixto, nelson javier | 2021-06-11

Physics includes the study and investigation of the phases that make up the hydrological cycle, including the estimation of flow rates in river basins, most of which are not instrumented, i.e., they lack historical records of circulating flows. For this situation, the application of hydrological models can allow flow estimates to be made. In the Department of Norte de Santander, Colombia, some watersheds do not have instrumentation for flow measurement or hydrological modeling methodologies appropriate to the site. Therefore, methods such as the modified rational model of Teméz are used, even without knowing the relevance of its applicability to the site conditions. Consequently, for the present research, the Teméz model was validated in watersheds of the Norte de Santander Department to estimate the values of extreme flows with a return period of 100 years. In this sense, 11 watersheds were selected, which contained historical rainfall data greater than 20 years and a drainage network of fewer than 1000 Km2. It was found that the Teméz model overestimates the real flows of the 11 hydrological basins, where the climatological parameters used in the application of the Fhrüling factor and its statistical verification using multivariate regression did not achieve an acceptable correlation.

Strengthening Critical Thinking in Engineering Students through Mathematics: The Power of Attitudes

PLAZA GÁLVEZ, LUIS FERNANDO | 2023-07-31

This study aims to strengthen critical thinking in future engineers through mathematics by stimulating their attitudes. To achieve this, a qualitative informative study will be conducted with a characteristic cut and a deductive orientation through the analysis and synthesis of contents from scientific publications specializing in the development of critical thinking. This type of thinking can be strengthened through strategies proposed by the mathematics teacher, allowing an increase in curiosity, eagerness to learn and inquire, and especially promoting and awakening curiosity in students through contexts where mathematics is formally applied in engineering. These strategies should include concrete actions that foster attitudes of critical thinking and a better ability to argue, interpret, and make judgments independently, ultimately acquiring a set of skills, especially in problem-solving. The results show that an engineering student as a critical thinker must have a critical attitude, which is evidenced through dispositions, habits, and character traits, which, when stimulated through mathematics, would contribute to their professional formation.

Una revisión sobre el tratamiento para lixiviados de rellenos sanitarios mediante el acople de procesos avanzados de oxidación y biológicos

Becerra Moreno, Dorance | 2023-09-08

El tratamiento de lixiviados de rellenos sanitarios requiere de procesos que permitan la remoción eficaz de los diferentes contaminantes presentes en este tipo de residuos líquidos. Para el tratamiento de este tipo de residuos se han empleado una gran diversidad de procesos biológicos, los cuales aprovechan la capacidad de transformar los diferentes componentes del medio liquido en biomasa, sin embargo, estos procesos poseen limitaciones debido a las características intrínsecas del lixiviado. En los últimos años se ha impulsado la integración de los procesos biológicos con los Procesos Avanzados de Oxidación, lo cual permitiría reducir significativamente las características toxicas de estos residuos para así cumplir con las condiciones legales para ser vertidos al ambiente sin que se produzcan daños. En la presente revisión se investigan los trabajos recientes (2015 a 2021) referentes al tratamiento biológico y con procesos Avanzados de Oxidación (basados en ozono, procesos electroquímicos y fotocatálisis). Estos procesos se analizan en combinación, para describir las condiciones óptimas en las que se reducen las cargas contaminantes de los lixiviados de rellenos sanitarios. Finalmente es posible identificar que los procesos de tratamiento en estudio son tecnologías que pueden ser acopladas, registrando mayor eficacia y menor generación de subproductos de desecho o lodos

Inquiry-based learning. Beliefs of trainee teachers in a physics course

Pabon Galan, Carlos Antonio | 2022

The teaching of physics should be supported by practical or laboratory activities that seek to develop the scientific competencies of the students who study physics, so it is necessary to propose innovative strategies, such as research-based learning, in which students answer research questions through the analysis of data, which increases the interaction between the student and the physical concepts under investigation. Therefore, the objective of the study was to analyze the beliefs of teachers in natural science training at a public university in Colombia who take the subject of physics on research-based learning, to provide information on how to guide the use of innovative strategies. The study responds to a type of quantitative research with a descriptive approach and was based on a field design. On the other hand, the results reflect slightly positive beliefs of students in initial teacher training who study physics about researchbased learning as an innovative strategy, although it is recommended to expand the sample to generalize. Finally, the analysis reveals as a conclusion that the implementation of innovative methodologies such as inquiry-based learning for science teaching, especially physics, should be promoted and supported more effectively to foster motivation, skills development, and conceptual understanding. of the scientific contents.

Computational tool for learning electrostatic physics through the development of a disruptive methodology

Ramírez Carvajal, Luis Eduardo | 2022-01-05

A computational tool for learning electrostatic physics is presented through the development of a disruptive methodology. The tool allows the analysis of case studies based on Coulomb’s law, Gauss’s law, Poisson’s equation, and Laplace’s equation with boundary value. The tool was tested using reference exercises for each case study, making use of quantitative and qualitative comparative analysis between the traditional mathematical development and the computational tool. Errors were measured using Likert scale. The quantitative results showed errors of less than 1.8% in all the cases studied, concluding that the tool is effective. The qualitative results showed that the methodology allows a better development of the electrostatics learning process, dynamizing the study of complex topics such as electromagnetic physics theories through interactivity and technological resources, in addition to having a theoretical module developed using agile methodologies that provide dynamism and an intuitive environment to the interface.