Browsing by Author "Pérez Vidal, Andrea"
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Item Análisis de peligros y puntos críticos de control en plantas convencionales de tratamiento de agua(Interciencia Association, 2018-01-16) Pérez Vidal, Andrea; Delgado Cabrera, Luis German; Escobar Rivera, Juan Carlos; Cruz Vélez, Camilo Hernán; Torres Lozada, PatriciaEl sistema de análisis de peligros y puntos críticos de control (APPCC) es una herramienta de amplio uso en la industria de alimentos y recomendada en el enfoque de los planes de seguridad del agua (PSA). En este estudio se adaptó una propuesta metodológica aplicable a los procesos de tratamiento de agua que integró los principios del sistema APPCC y los PSA. El estudio se realizó en una planta convencional de potabilización (PTA) en la ciudad de Cali, Colombia, y comprendió dos etapas: 1) identificación de peligros y eventos peligrosos, y 2) determinación de puntos críticos de control (PCC) y puntos de atención (POA). En la primera etapa se caracterizó el agua cruda, clarificada, filtrada y tratada mediante diez jornadas de muestreo y caracterización, en un periodo de 18 meses. En la segunda etapa se adaptó un árbol de decisión que fue aplicado en los eventos peligrosos categorizados en nivel de riesgo medio o superior. Se identificaron un total de 40 eventos peligrosos, 26 PCC y 10 POA, encontrándose como principales PCC las fases de coagulación, floculación/clarificación, filtración y desinfección. La determinación de los PCC contribuyó a la priorización de las fases del tratamiento que requieren de la ejecución de planes de mejoramiento o soporte definidos en los PSA, resultando prioritarios la captación, canales y tuberías de conducción.Item Biological stability and phytotoxicity of sludge generated from extended aeration activated sludge systems(Elsevier B.V., 2025-02) Cárdenas Talero, José Luis; Millán Castro, María del Mar; Silva Leal, Jorge Antonio; Pérez Vidal, Andrea; Torres Lozada, PatriciaActivated sludge technology is widely used for treating municipal wastewater. In particular, the extended aeration activated sludge (EAAS) method shows longer sludge retention time (SRT), which may enhance the biological stability of the resulting sludge. In this study, the biological stability of secondary sludge without dewatering (SS) and dewatered secondary sludge (DSS), dried in a conventional drying bed for 25 days, were examined using two full-scale EAAS systems operating under varying environmental and operational conditions (EAAS1: 24 °C; 926 masl; SRT 16.8 days and EAAS2: 16 °C; 2513 masl; SRT 23.6 days). The volatile solids to total solids ratio (VS/TS), volatile solids reduction (VSR), and specific oxygen uptake rate (SOUR-20) were assessed as indicators of biological stability. Germination tests (phytotoxicity) using radish seeds were conducted with soil-to-sludge mixtures (0:100, 25:75, 50:50, 75:25) and controls of soil only and distilled water. SRT showed a strong correlation with the biological stability of sludge. The EAAS systems did not ensure biological stability for SS, DSS did achieve biological stability, indicating that the dewatering stage, in addition to reducing moisture, contributes to the biological stabilization of the sludge. Heavy metal concentrations in SS and DSS were within regulatory limits, but pathogen levels exceeded them. Phytotoxicity in the SS and DSS was observed at higher sludge concentrations (0:100, 25:75), but the 50:50 mixture showed no toxicity, and the 75:25 mixture even enhanced germination. The results showed that DSS from EAAS systems have agricultural potential; however, their use is contingent upon additional treatments to eliminate pathogens.Item Comparación de dos instrumentos de medición de presión de biogás con aplicación en ensayos de potencial bioquímico de metano (PBM) en digestión anaerobia de residuos de alimentos(Universidad Santiago de Cali, 2024) Popayan Copete, Paul Alejandro; Sanchez Bustos, Mayra Alejandra; Pérez Vidal, AndreaAnaerobic digestion (AD) is a biological process in which bacteria decompose organic matter without oxygen, generating biogas, a renewable and versatile source of energy. Biochemical Methane Potential (BMP) assays measure the amount of methane (CH4) produced per gram of volatile solids (VS) in a substrate under controlled conditions, assessing the feasibility of obtaining energy from the anaerobic degradation of various wastes. In this work, the feasibility of obtaining energy was evaluated by BMP assays in AD with food residues, using a substrate/inoculum (S/I) ratio of 0,25 g VS substrate/g VS inoculum. Two types of anaerobic digestion (wet and dry), three headspace percentages (20%, 50%, 75%) and two biogas measuring instruments (pressure gauge and pressure sensor) were investigated. The results showed significant changes in biogas production according to the type of digestion, achieving a higher volume of CH4 with dry digestion due to the organic load in the reactors. It was observed that the treatment with the lowest headspace (20%) obtained a lower BMP value and with 50% the most favorable results were achieved in the BMP such as avoiding biogas dissolution. In relation to biogas measuring instruments, it was found that with the use of a pressure gauge, biogas losses are generated with each punch to the reactor, underestimating the BMP calculation between 16%-35% in DD and 12%-46% in WD. On the contrary, with the pressure sensor, it was easier to obtain data without interventions in the reactor, obtaining higher values in the production of biogas. The most beneficial treatment was measured through the pressure sensor with a 50% headspace and dry digestion, generating a BMP value of 187.21 (ml/grSV).Item Development and implementation of a water-safety plan for drinking-water supply system of Cali, Colombia(Elsevier GmbH, 2019-11-25) Pérez Vidal, Andrea; Escobar Rivera, Juan Carlos; Torres Lozada, PatriciaThe water-safety plan (WSP) approach integrates risk assessment and management practices into a drinking-water supply system (DWSS), ensuring water quality from the catchment to the consumer. This research was oriented toward the development and implementation of a WSP in the DWSS for the city of Santiago de Cali, Colombia. We adapted the methodological stages of the WSP established by the World Health Organization: (i.) assemble a WSP team, (ii.) describe the existing DWSS, (iii.) identify hazards and hazardous events, (iv.) evaluate risks, and (v.) plan risk management. In this methodological structure, we propose the use of different risk assessment tools at each step of DWSS, which can be implemented in water systems of different sizes. The results of our study allowed the identification of hazardous events that may compromise the effectiveness of the WSP: Of the 103 events found, 16 were related to the catchment, 40 to treatment processes, 27 to the distribution system, and 9 to consumers, while the remaining 11 were associated with organizational, planning, contingency, and emergency factors. We found that the most critical components of the DWSS are the distribution system and the consumers, with 29.6% and 33.3% of the hazardous events classified as at a very high risk level, respectively. Clearly, improvement and support programs for the WSP were needed to optimize existing control measures and corrective actions and to evaluate new ones to reduce risk levels. The treatment processes and distribution system steps were shown as the main barriers of the DWSS mainly they are under governance of water company, unlike the catchment and consumers which presented higher levels of risk because in these steps the water company has less control and influence. Our research confirms that the WSP is an important tool for decision-making by water-service companies—improving their administrative, financial, organizational, and operational management. It also shows that it is essential that their senior management and other stakeholders be part of the WSP team at each stage of implementation of the DWSS.Item Effect of biosolids on the nitrogen and phosphorus contents of soil used for sugarcane cultivation(2021) Silva Leal, Jorge Antonio; Pérez Vidal, Andrea; Torres Lozada, PatriciaThe application of biosolids improves soil nutrient availability and crop productivity; however, their application needs to be carefully evaluated so as to avoid the risk of contamination. In this study, a 12-month field experiment using a randomized block design with factorial arrangement was conducted to evaluate the effects of biosolids on the nitrogen and phosphorus contents of a sugarcane-cultivated inceptisol. Three types of dewatered biosolids were used: anaerobically digested (B), anaerobically digested and thermally dried (BST), and anaerobically digested and lime-stabilized (BA) biosolids. The results showed that biosolid use increases soil nitrogen content by up to 37% of the total Kjeldahl nitrogen, 42% of NO3−, 13% of NO2−, and 32% of NH4+. Biosolid treatments exceeded the phosphorus requirement for sugarcane cultivation by up to 277% for B, 170% for BST, and 368% for BA. The application of biosolids sufficient to meet crop nitrogen requirements significantly increased soil phosphorus content, suggesting an overdose and low crop response to the available phosphorus. The application of biosolids yielded results similar to those of mineral fertilizers, suggesting their potential use in agriculture.Item Estudio comparativo de dos sistemas de filtración casera para el tratamiento de agua para consumo humano(2014-12-13) Pérez Vidal, Andrea; Díaz Gómez, Jaime; González Rojas, Ginna PaolaEl tratamiento de agua para consumo humano a nivel de la vivienda es una opción viable para mejorar y asegurar la calidad del agua, principalmente en lugares que no cuentan con sistemas de tratamiento centralizados, los sistemas existentes operan de manera deficiente o existen condiciones de sequía. En este estudio se evaluaron dos sistemas de filtración casera, un filtro de 1 vela (1VC) y 2 velas cerámicas (2VC) durante 6 meses. Se evaluó la eficiencia de reducción de turbiedad y E. coli y aspectos relacionados con su operación y mantenimiento. Se empleó un sustrato sintético cuyo valor promedio de turbiedad fue de 32.7± 2.81 UNT y 3.9x105 UFC/100ml de E. coli. Los resultados mostraron que ambos sistemas de filtración lograron reducir la turbiedad a valores promedio de 0.28 UNT (99% de eficiencia) y eliminar E. coli entre 99.999 y 100%. No se encontraron diferencias estadísticas significativas en términos de la calidad de agua filtrada por ambos sistemas, sin embargo, fueron evidentes diferencias desde el punto de vista económico, operativo y de mantenimiento.Item Evaluación de la eficacia del plan de gestión integral de residuos sólidos en el sur de la ciudad de Montería-Córdoba(Universidad Santiago de Cali, 2019) Córdoba Hernández, Jairo Andrés; Pérez Vidal, AndreaEvaluate the effectiveness and adequate applicability of the integral solid waste management plan in the south of the city of Montería Córdoba. Materials and methods. Two neighborhoods in the south of Montería (Colina Real and Furatena) were chosen with evident problems derived from the inadequate disposition of garbage. This two sectors, represented a total population of 1,200 inhabitants distributed in 653 people for Royal Hill and 547 for Furatena. The integral solid waste management plan - PGIRS was reviewed and surveys were applied as an instrument for collecting primary information, applying a snowball sampling. Results For the Furatenas and Colina real neighborhoods, there was a good acceptance of the collection processes with averages of 50-66% and transport with 40-95%. On the other hand, in both neighborhoods there was a bad execution of storage with percentages of 21-85% and final disposal of waste with 85-93%, the latter process being the one that should improve the most according to the inhabitants' consideration. The problem of storage in the Colina Real neighborhood presents a reduction with an average of 79% with respect to Furatena due to the knowledge of the population about the good disposal of waste in the home. In both neighborhoods, most of the inhabitants do not make separation at the source or do not do it properly. Although in Colina Real the municipality in collaboration with the company in charge of waste carries out environmental education campaigns established in the PGIRS to be executed in some neighborhoods of the municipality of montería. Conclusion. It was established that the integral solid waste management plan presents a good efficiency in terms of the processes of collection and transportation of the basic waste in the Furatena and Colina Real neighborhoods in the south of Montería, nevertheless it requires considerable improvements in storage and mainly in the final disposition established in specific points in the PGIRS. The separation at the source is an activity partially carried out in both neighborhoods as well as environmental education generating the need for greater municipal intervention. Keywords: solid waste; harvest; transport; storage; final disposition; separation at the source; environmental education.Item Evaluación del desempeño del filtro de olla cerámica EKOFIL® bajo dos concentraciones de plata coloidal(Universidad Santiago de Cali, 2020) Cuastumal Recald, Jorge Alexander; Méndez Posso, José Leonardo; Pérez Vidal, AndreaThe ceramic pot filter technology impregnated with colloidal silver is a viable alternative for the treatment of water for human consumption, characterized by its low cost, ease of handling and efficiency. In this research project, the performance of a Colombian-made filter model, impregnated with two concentrations of colloidal silver (500 ppm and 1000 ppm) was evaluated. PH, conductivity (µS/cm) and turbidity (UNT) were defined as follow-up variables and as a response variable total silver (mg/L). Synthetic water was used adjusting turbidity with kaolin (5.07 ± 0.51 UNT) and conductivity with NaCl (0.37 ± 0.5 µS/cm). The filters were evaluated under two operational conditions based on the pH of the synthetic water or tributary; in the first condition the pH was of the order of 8.60 ± 0.83 units and in the second of 5.36 ± 0.25 units. Additionally, in the first condition, synthetic water was inoculated with an average E.coli concentration of 2.1 x 103 CFU / 100 mL in order to evaluate the influence of the colloidal silver concentration on the microbiological removal efficiency. The results of the study showed that there is no significant statistical difference between 500 ppm and 1000 ppm filters in terms of the removal of E.coli in the effluent (gl=18, F=18.8.49, p=0.41) reaching average efficiencies 98%, in addition to evidencing that there is no health risk since the maximum concentration measured was 0.03 mg Ag/L in the 1000 ppm filter. The average turbidity of the effluent was 0.47 ± 0.22 UNT for the 500 ppm filter and 0.59 ± 0.25 UNT for the 1000 ppm filter, showing that there are no significant statistical differences in terms of turbidity (gl=43, F=47.49, p=0.29 ). It is concluded that increasing the concentration of silver in the filters does not influence the efficiency of microbiological removal and, on the contrary, it could unnecessarily increase the cost of the filtration system, being advisable to impregnate the ceramic pot with a concentration of 500 ppm.Item Evaluación del tratamiento de agua para consumo humano mediante filtros Lifestraw® y olla Cerámica(Universidad Nacional de Colombia, 2015-11-18) Pérez Vidal, Andrea; Díaz Gómez, Jaime; Salamanca Rojas, Karen L.; Rojas Torres, Leidy Y.Objetivo: Evaluar la eficiencia de dos sistemas de filtración casera: LifeStraw® family (FM) y Filtro de Olla Cerámica (FOC) en el tratamiento del agua para consumo humano bajo condiciones controladas de laboratorio y en términos de remoción de Turbiedad y E.coli. Métodos: Ambos sistemas se operaron durante 6 meses tratando diariamente 7,5 litros de sustrato sintético. La turbiedad del sustrato se ajustó con Caolín y la concentración de E.coli con la réplica de la cepa ATCC 95922. Los resultados obtenidos en términos de remoción de turbiedad y E. coli fueron evaluados con un análisis de varianza (ANOVA) y considerando aspectos operativos y de mantenimiento. Resultados: La turbiedad del sustrato sintético presentó un promedio 32,3 ± 2,8 UNT y la concentración de E. coli 3,9 x105 UFC/100mL. Ambos sistemas de filtración disminuyeron la turbiedad a niveles menores de 2 UNT y lograron la inactivación del 100 % de E.coli. Se encontraron diferencias significativas en la remoción de turbiedad siendo más eficiente el FM (99,2 % ± 0,4) que el FOC (97,6 % ± 1.14). Conclusiones: Los dos sistemas de filtración son adecuados para el tratamiento del agua a nivel casero, cumpliendo con la reglamentación Colombiana. El FM resultó más eficiente en remoción de turbiedad y tasa de filtración; Sin embargo, cuando se tienen en cuenta aspectos como aceptabilidad social operación, mantenimiento y vida útil, el filtro de olla cerámica parece más apropiado especialmente en áreas rurales.Item Hazard identification in watersheds based on water safety plan approach: Case study of Cali-Colombia(Gheorghe Asachi Technical University of Iasi, Romania, 2016-04) Pérez Vidal, Andrea; Torres Lozada, Patricia; Escobar Rivera, JuanWithin the framework of the Water Safety Plan (WSP), it is necessary to assess and to manage risks in the catchment area, considered the first protection barrier of water supply systems. The Cauca River is one of the major water resources of Colombia and the principal source of drinking water supply for the city of Cali (approx. 2,300,000 people). Taking into account, usually in developing countries, available information and specialized technical resources are limited, in this study were evaluated three management tools of simple application for hazard identification, as a support of risk assessment in the watersheds and integrated with the WSP methodology. The used tools were: (i) matrix of hazardous events, (ii) calculation of Water Quality (WQI) and Water Pollution (WPI) Indexes, and (iii) hazard maps using Geographic Information Systems (GIS). The results showed that the progressive deterioration of water quality is associated with different types of land use of the watershed, which causes diffuse pollution and point source pollution, resulting in the exposure of served population to health risks if adequate treatment barriers are not implemented before the distribution to consumers. The three evaluated tools, showed their usefulness as inputs to risk management and support in activities of surveillance and water quality control. It is important to highlight that the strengthening of the cooperation and active participation of inter-agencies and stakeholders are crucial strategies for risk management in the watersheds.Item Impacto ambiental de la mineria de oro en el departamento del Choco(Universidad Santiago de Cali, 2018) Ruíz Mena, Dayron; Pérez Vidal, AndreaThis article contains a review about the impacts caused by gold mining. This activity generate a big habitat destruction that involves to the interruption of ecosystems affecting the connection between the elements that make up the surrounding natural ecosystems. This document has the purpose of documenting the mining context and the damages caused in the Chocó Department. This manuscript shows how dangerous chemicals such as cyanide and mercury in the extraction of this mineral are used. It use caused numerous impacts in natural space which affect the environment and human health. In Colombia, the first’s gold main are produce in Antioquia (49%), Chocó (20%) and Nariño (9%). Illegal mining is one of the most informal activities in the country, due to that taxes are not paid to the state, it does not have elements of labor protection and safety, it generates loss of human lives. This analysis is the result of the compilation and documentation of actors who has studied this activity; appreciations that show how the mining that is practiced in the opencast and underground gold impacts on biodiversity and social groups that are the main actors of this problem. Currently, if viewed from the social point of view, mining in the Chocó has caused more harm than benefits to the communities. Much of this activity is informal and illegal with some cases in the process of formalization. Despite this dynamic, Chocó is full of strong and solid organizational processes of black and indigenous communities that, among other things, have been fighting for decades for the country to recognize in its Constitution, its interethnic and plurinational nature for the management of areas in which they have lived ancestrally.Item Manejo de excretas y aguas residuales en comunidades rurales. Efectos en la salud pública(Universidad Santiago de Cali, 2020) Piza De La Hoz, Janis Jaqueline; Pérez Vidal, AndreaIn the 21st century, urban and rural communities have a serious environmental and public health problem because they do not have an adequate process of liquid waste management that is controls of domestic management, of agricultural and industrial processes. The majeo and treatment of wastewater and excreta is important because it affects the physical and chemical conditions of the water and in turn generates a negative impact on people's health. This reflection article focuses on the bibliographic review of the conceptual elements that allow the understanding of the management of wastewater and excreta taking into account the impact that is generated on the physical, chemical and health factors, a review of the experiences of wastewater management in Latin America and in the Colombian context, a balance on wastewater treatment technologies in rural areas was also carried out. Next, an analysis is carried out on the characteristics of the wastewater and its relation to public health. Additionally, a collection of primary information was carried out in the community of Vereda El Peón, corregimiento de Pance, rural area of Santiago de Cali, Valle del Cauca - Colombia, In order to identify the health problem related to the management of excreta and wastewater, they especially affect the youth population. In conclusion, the treatment of wastewater is relevant in the community for public health and the environment.Item Manejo inadecuado de residuos sólidos urbanos desde una perspectiva técnica y psicosocial(Universidad Santiago de Cali, 2019) Gómez Ordoñez, Luz Zenaida; Pérez Vidal, AndreaResearchers of environmental problems, in the area of social sciences, emphasize that to try to solve environmental problems due to the accelerated and irreversible degradation and / or disappearance of natural resources, it is not enough to implement strategies for the treatment of SRs and emphasize the need to know the processes through which behavior and attitudes about the environment are developed (De Castro, 1994). Mosler (1993) points out that “the current environmental problems are not problems between people and the environment, but rather as a product of the problems among the members of a social system.” Therefore, this bibliographic review article aimed to identify the factors that influence the behavior of a person, compared to the management of waste using as a basis the Theory of Reasoned Action (TAR) of Ajzen and Fishbein (1980), which states that each person with their values, beliefs, information and behavior prints particular characteristics to the space that inhabits and the elements of said space and highlights the importance of the modification of the behavior and attitudes of each individual in a given space.The document was articulated in three sections, the first describes the generalities of integral management of solid waste (GIRS), the second one deepens the importance of environmental education (advances and limitations) and Finally, the psychosocial aspects associated with solid waste disposal are described. Finally, it was found that factors such as economic, cultural and knowledge about the importance of environmental protection and about the methods of recycling and classification of solid waste, influence the behavior of each person individually and collectively in solid waste management.Item Metodologías de caracterización de residuos sólidos urbanos. Una revisión(Universidad Santiago de Cali, 2019) Castro Velazco, Leidy Paola; Pérez Vidal, AndreaSolid waste characterization methods are destined for the determination of the physical composition, generation rates and per capita production of different waste generated in municipalities, factories, institutions or selected study areas, they allow to evaluate generation of populations trends as well as the amounts of waste according to the economic activities that are carried out. They are characterized by being suitable for their execution in different places which can be the generating sources or the final disposal spaces, they have their own evaluation parameters in the production of waste according to the information to be obtained, total volume or volume fraction, weight of waste, densities or future generation projections. The comparison of the methods allows to know the viability of each, the duration and frequency that entails its realization and the complexity that its processes encompass as established in the theory elaborated by researchers in the characterization studies. The methods of difference of weights and quartering, weight-volume analysis, analysis of the number of loads, mass balance and analysis by statistical sampling show that each one can be applied according to the information requirements that one wishes to determine because each one establishes a flexible methodology that is easy to implement as a tool to improve information on the generation and composition of solid waste. The quartering and analysis by statistical sampling are applicable methods for Colombia because they allow obtaining the physical composition of the waste to know the percentages of waste generation, production per capita, generation per capita, current waste quantity and future generationItem Minería de oro de aluvión: Efectos en el recurso hídrico y la salud de los mineros(Universidad Santiago de Cali, 2020) Loboa Balanta, Liliana; Pérez Vidal, AndreaGold mining is a profitable activity in the world. The gold costs tend to increase annually on the world market at the same time, in turn increasing mining activity. The gold mining is classified according to precedence in primary and secondary; the secondary refers to alluvial deposits of gold. The gold extraction techniques could vary according to the mining scale and level of technology. Many gold companies around the world use toxic chemicals like mercury, affecting the environment, water resources and some ecosystems through the accumulation and biomagnification processes. Also, the mercury affects the human health, causing different types of cancer. The gold mining practices in developing countries have many risks that have been triggered by political, social, economic, and administrative factors, affecting the worker health. In this review paper, mining exploitation was approached with a world-wide vision, climbing to the national level and to the Cauca region, particularly observing the local reality in the municipalities of Suárez, Buenos Aires and Santander de Quilichao. These latter municipalities report inadequate management of substances such as mercury, which has generated environmental and public health effects from the irrational use of this chemical. Additionally, the pilot experience of the La Estrella mine in the municipality of Suárez is reported, which has been applying clean mining and has completely replaced the use of polluting substances such as mercury and cyanide.Item Minería de oro: Tecnologías de Extracción, Ventajas y Efectos(Universidad Santiago de Cali, 2020) Lucumí Golu, Hugo Jair; Colorado Aponza, Pablo César; Pérez Vidal, AndreaGold is an element with various industrial uses as electrical conductor in the microprocessor development or as a luxury item. Gold is naturally stored in veins or in alluvial deposits and therefore the technologies used for its extraction may vary. This review paper presents an analysis of the exploitation methods, technologies, advantages, and effects of gold mining, focused on the Colombia context. In the extraction of gold by alluvium, methods such as gravimetric concentration or batting, amalgamation and in a few cases distillation are highlighted, using motorized pumps, water monitors used for crumbling material, dredges, backhoes and bulldozers. Meanwhile, the vein gold extraction process highlights methods such as crushing, grinding, amalgamation and cyanidation, which employ technologies similar to the previous process with the difference of the use of furnaces and torches. The main advantage associated with gold mining is the source of economic incomes for millions of people. Unfortunately, the absence of government entities in charge of regulating mining activities and the inadequate use of their equipment and machinery seriously affect the environment and human health.Item Performance evaluation of ceramic pot filters combined with adsorption processes for the removal of heavy metals and phenolic compounds(2021) Pérez Vidal, Andrea; Silva Leal, Jorge Antonio; Diaz Gómez, Jaime; Meneses Torres, Camilo J.; Arias Vallejo, Juan E.; Giraldo Tenorio, Giovanna A.; Bacca Jordán, Maria CamilaIt has been demonstrated that the ceramic pot filters (CPFs) with impregnated colloidal silver are efficient for the removal of turbidity and pathogens for household water treatment. This investigation evaluated the efficiency of two filter models for the removal of chemical contaminants (Hg, Pb, As and phenolic compounds) during 175 days. The first model is a traditional CPF impregnated with colloidal silver and the second consists of the ceramic silver-impregnated pot plus a post-filtration column with granular activated carbon and zeolite (CPF þ GAC-Z). The results of the CPF showed average efficiencies of 91.5% (Hg), 92% (Pb), 50.2% (As) and 78.7% (phenols). The CPF þ GAC-Z showed similar efficiencies for the removal of heavy metals (92.5% Hg, 98.1% Pb and 52.3% As) and a considerably higher efficiency for the removal of phenols (96.4%). The As concentration of the filtered water in both systems was higher than the regulatory limit. The ceramic pot was responsible for the highest removal of chemical compounds. It can be concluded that the traditional CPF is a viable option for water supply treatment at the household level for the removal of chemical contaminants. The efficiency of this filter can be improved with the post-filtration column mainly for the removal of organic constituents.Item Physicochemical, microbiological characterization and phytotoxicity of digestates produced on single-stage and two-stage anaerobic digestion of food waste(2021) Parra Orobio, Brayan Alexis; Rotavisky Sinisterra, María Paula; Pérez Vidal, Andrea; Marmolejo Rebellón, Luis Fernando; Torres Lozada, PatriciaOrganic amendments favor the development of sustainable agriculture by using less chemical fertilizers. In this way, the use of digestates from anaerobic digestion as soil conditioners in agriculture has been gaining interest due to their important N and P nutrient contents, among others. This study evaluated the potential use of digestates from anaerobic reactors treating food waste in single (D1) and two-stages (D2: hydrolytic/acidogenic and D3: acetogenic/methanogenic) configurations. Digestate characteristics and their potential application conditions (100, 50, 25, and 5%) were evaluated using Raphanus sativus as an indicator species. D3 reported the best performance in terms of: (i) better physicochemical, microbiological, and parasitological characteristics, being a class B material, without exceeding the established limits for heavy metals, fecal coliforms (FC < 1000 CFU 100 mL− 1), Salmonella spp. (0 CFU g− 1), and viable helminth eggs (0 HE g− 1); (ii) better stability indicators on D3, followed by D1 (volatile solids/total solids (VS/TS): 0.57 and 0.65, pH: 8.63 and 6.80, respectively), while D2 was the most unstable digestate (VS/TS > 0.87 and acidic pH); and (iii) greater potential for agricultural use, since a 5% dose produced a germination index > 120%, whose effect is associated with the presence of humic and fulvic acids and with N and P concentrations > 1%. In addition, the study reported that volatile fatty acids > 2500 mg L− 1 act as antimicrobial agents, reducing the required pathogen removal pretreatments.Item Plan de gestión integral de residuos sólidos de la estación de servicio Texaco Obrero en la ciudad de Santiago de Cali(Universidad Santiago de Cali, 2016) Cabrera Trujillo, Alejandra; Sanchéz Muñoz, Miguel Angel; Pérez Vidal, AndreaItem Potential production of struvite from the anaerobic digestion of food waste: Analysis in one-phase and two-phase configurations(2021) Parra Orobio, Brayan Alexis; Pérez Vidal, Andrea; Torres Lozada, PatriciaAnaerobic digestion (AD) of food waste (FW) has been gaining more interest as it has potential for the production of organic amendments with high struvite content, which is a nutrient of great interest in sustainable agriculture. The effect of AD of FW in one- and two-phase configurations on CH4 production and the potential for struvite formation using digestate was investigated. The two-phase was more efficient as its organic loading rate is 18% higher than that of one-phase configuration. Also, the two-phase yielded a higher CH4 content in biogas (>60%) and a higher organic matter transformation in each of the AD stages (>20%). The digestate complied with the regulatory requirements for the use of organic amendments, thereby being deemed as a Type-B material with a struvite precipitation potential, exceeding 80%, as opposed to the digestate from one-phase configuration, which may represent a revenue of up to US$ 26,505/yr.