Abstract Textile sludge is a waste from the effluent treatment of textile laundries and its incorporation into alternative materials has been proposed as a possibility for its disposal. A systematic search was carried out in literature from this perspective, aiming to observe concentrations of waste material and its preparation, matrices used, technological performance and immobilization of textile waste. The matrices used were mortars, concretes and ceramic bricks, in general, deleterious effects were observed on mechanical characteristics of the materials produced. In concrete and mortars, the fineness had an impact on increase in water demand, which increased mixtures porosity; and organic matter and heavy metals, in cement hydration. Recent studies therefore proposed waste material pre-treatment as a favorable alternative. Increases in porosity also occurred in ceramic bricks, however, due to high organic matter content. Regarding waste immobilization, cementitious materials showed satisfactory performance; ceramic bricks, on the other hand, obtained some results outside the normative limits. Therefore, it is necessary to expand discussions regarding the pre-treatment carried out on textile sludge, as well as its impacts on mechanical and environmental performance. disposal perspective preparation mortars bricks general produced demand metals hydration pretreatment pre however content hand limits Therefore

Resumo Olodo têxtil é um resíduo do tratamento do efluente das lavanderias têxteis e sua incorporação em materiais alternativos tem sido proposta como possibilidade para sua destinação. Foi realizada uma busca sistemática na literatura nesta perspectiva, visando observar as concentrações de material residual e seu preparo, as matrizes utilizadas, o desempenho tecnológico e imobilização do resíduo têxtil. As matrizes empregadas foram argamassas, concretos e tijolos cerâmicos, sendo observados, de maneira geral, efeitos deletérios nas características mecânicas dos materiais produzidos. Em concretos e argamassas, a finura impactou no aumento da demanda de água, o que elevou a porosidade das misturas; e a matéria orgânica e metais pesados, na hidratação do cimento. Estudos recentes propuseram, então, o pré-tratamento do material residual como uma alternativa favorável. Incrementos na porosidade também ocorreram nos tijolos cerâmicos, porém, devido ao elevado teor de matéria orgânica. Quanto a imobilização do resíduo, os materiais cimentícios apresentaram desempenho satisfatório; já os tijolos cerâmicos, obtiveram alguns resultados fora dos limites normativos. Portanto, é necessário ampliar as discussões quanto ao pré-tratamento realizado no lodo têxtil, bem como seus impactos no desempenho mecânico e ambiental. destinação perspectiva preparo utilizadas argamassas cerâmicos observados geral produzidos água misturas pesados cimento propuseram então prétratamento pré favorável porém satisfatório normativos Portanto ambiental

The Cuban industry La Purísima produces sauces and dressings for the national gastronomy; but it does not have a process for the deposition of chicken eggshells, as a result, 220 kg of eggshells are dumped daily, which generate a negative impact on the environment. The research evaluates the drying of hen eggshells with protein membrane on a laboratory scale, with a view to revalorizing this waste in the production of a calcium-rich poultry feed supplement. The calcium carbonate content of the shell was determined to confirm the potential application of the residue. The drying curve and drying rate curve was obtained by experimental measurement in a drying oven under aeration at 90 °C. The calcium carbonate content of the residue was 93,33 %. The drying curve was fitted to an exponential mathematical model as a function of the drying constant and the moisture in equilibrium at a temperature of 90 °C. The drying regime of the solid presented a period of decreasing drying rate up to a moisture value of 0,021 kg of water / kg of dry solid, for lower values, this presented a deviation from the exponential function in its rate. The utilization of residual eggshells proved to be an attractive source of calcium carbonate with potential for its use in the production of feed supplement for poultry.

RESUMEN En la Industria cubana La Purísima se producen salsas y aderezos para la gastronomía nacional; pero no dispone de un proceso para la deposición de las cáscaras de huevo de gallina, como resultado, se vierten diariamente 220 kg de cáscaras que generan un impacto negativo en el medio ambiente. La investigación evalúa el secado de las cáscaras de huevo de gallina con membrana proteica a escala de laboratorio, con vistas a revalorizar este residuo en la producción de un suplemento alimenticio para aves de corral rico en calcio. Se determinó el contenido de carbonato de calcio en la cáscara para confirmar la aplicación potencial del residuo. La curva de secado y del régimen de secado se obtuvo por medición experimental en un secadero bajo aireación a 90 °C. El contenido de carbonato de calcio en el residual fue de 93,33 %. La curva de secado se ajustó a un modelo matemático exponencial en función de la constante de secado y la humedad en equilibrio a una temperatura de 90 °C. El régimen de secado del sólido presentó un período de velocidad de secado decreciente hasta un valor de humedad de 0,021 kg de agua / kg de sólido seco, para valores inferiores presentó una desviación de la función exponencial en su velocidad. El aprovechamiento de las cáscaras de huevo residuales resultó ser una fuente atractiva de carbonato de calcio con potencialidades para su utilización en la elaboración de suplemento alimenticio para aves de corral.

ABSTRACT Custard apple (Annona squamosa L.) is a sensitive fruit crop to salinity. One of the alternatives to minimize the deleterious effects of salt stress is adopting mineral fertilization management practices, promoting increased crop tolerance to salts. Therefore, the objective of the present study was to evaluate NPK doses to mitigate salt stress in custard apple seedlings irrigated with saline wastewater. The experiment was performed in a greenhouse, adopting a randomized block design in a 3 × 5 factorial scheme, corresponding to three irrigation waters (local-supply water of 0.53 dS m-1 electrical conductivity (control); desalination reject of 3.5 dS m-1; fish farming effluent of 3.5 dS m-1) and five proportions of the NPK recommendation (25, 50, 75, 100, and 125% of the fertilization recommendation), with four replicates. The growth, biomass accumulation, and nutrients were evaluated. Irrigation with desalination reject, and fish farming effluent restricted the growth of custard apple seedlings, regardless of the NPK dose used. The ionic homeostasis of seedlings irrigated with desalination reject and fish farming effluent is optimized by fertilization with 50% of the NPK recommendation corresponding to 50, 150, and 75 mg of N, P2O5, and K2O dm-3, respectively. For the production of seedlings irrigated with local-supply water, the dose of 75% NPK, corresponding to 75, 225, and 112.5 mg of N, P2O5, and K2O dm-3, respectively, is recommended. Annona L. L salinity practices salts Therefore wastewater greenhouse scheme localsupply local supply 053 0 53 0.5 m1 m 1 m- control (control) 35 3. 25, 25 (25 50 100 125 recommendation, , recommendation) replicates accumulation evaluated used 150 7 N P2O5 PO P O KO K dm3, dm3 dm 3, dm-3 respectively 225 1125 112 112. recommended 05 0. (control 2 (2 10 12 15 P2O dm- 22 11 (

RESUMO A pinheira (Annona squamosa L.) é uma frutífera sensível à salinidade. Uma das alternativas para minimizar os efeitos deletérios do estresse salino é a adoção de práticas de manejo da fertilização mineral, promovendo o aumento da tolerância da cultura aos sais. Portanto, o objetivo foi avaliar as doses de NPK para mitigar o estresse salino em mudas de pinheira irrigadas com água residual salina. O experimento foi realizado em casa de vegetação, em delineamento de blocos casualizados, em esquema fatorial 3 × 5, correspondendo a três águas de irrigação (água de abastecimento local de 0,53 dS m-1 de condutividade elétrica (controle); rejeito salino da dessalinização de 3,50 dS m-1; efluente de piscicultura de 3,50 dS m-1) e cinco proporções da recomendação de NPK (25, 50, 75, 100 e 125% da recomendação de fertilização), com quatro repetições. O crescimento, acúmulo de biomassa e nutrientes foram avaliados. A irrigação com rejeito salino e efluente de piscicultura restringe o crescimento das mudas de pinha, independentemente da dose de NPK utilizada. A homeostase iônica das mudas irrigadas com rejeito salino e efluente de piscicultura é otimizada pela fertilização com 50% da recomendação de NPK correspondente a 50, 150 e 75 mg de N, P2O5 e K2O dm-3, respectivamente. Para a produção de mudas irrigadas com água de abastecimento local, recomenda-se a dose de 75% de NPK, correspondente a 75, 225 e 112,5 mg de N, P2O5 e K2O dm-3, respectivamente. Annona L. L salinidade mineral sais Portanto salina vegetação casualizados 5 053 0 53 0,5 m1 m 1 m- controle (controle) 350 50 3,5 25, 25 (25 10 125 fertilização, , fertilização) repetições avaliados pinha utilizada 15 7 N PO P P2O KO K dm3, dm3 dm 3, dm-3 respectivamente recomendase recomenda se 22 1125 112 112, 05 0, (controle 35 2 (2 12 dm- 11 (

ABSTRACT The paper analyzes the quality of the water supplied by the potable water treatment plant Altos of Quintero to the city of Santiago de Cuba through the study of five consumers. The quality of the parameters analyzed was determined for pH, color, turbidity, residual free chlorine and determination of total and fecal coliforms, resulting in La Colonia, La Cervecería Hatuey and the Combined Milk, which residual free chlorine and turbidity are outside the norm in some occasions. The effects of the quality of drinking water coming from the potabilizer were mainly the deterioration of the infrastructure of the supply networks and poor storage conditions of the liquid in the above mentioned institutions. Options are presented to ensure that water quality is maintained in the different consumption centers and a predictable model is proposed that allows the maximum time that guarantees the minimum level of allowable residual chlorine that a consumer source should have.

RESUMEN El trabajo analiza la calidad del agua que suministra la potabilizadora Altos de Quintero a la ciudad de Santiago de Cuba mediante el estudio de cinco consumidores. Al agua de los seis centros analizados se les determinó su calidad por la medición de los parámetros: pH, color, turbidez, cloro libre residual y determinación de coliformes totales y fecales, resultando La Colonia, La Cervecería Hatuey y el Combinado Lácteo las entidades en las cuales el cloro libre residual y la turbidez se encuentran fuera de norma en algunas ocasiones. Las afectaciones de la calidad del agua potable procedente de la potabilizadora se deben fundamentalmente al deterioro de la infraestructura de las redes de abastecimiento y a las malas condiciones de almacenamiento del líquido en las instituciones antes mencionadas. Se presentan opciones para garantizar que se mantenga la calidad del agua en los diferentes centros de consumo y se propone un modelo predictivo que posibilita determinar el tiempo máximo que garantiza el mínimo nivel de cloro residual libre permisible que debe disponer una fuente consumidora.

ABSTRACT Introduction: The balance of materials in obtaining the G-0 intermediate product guarantees that the product is consistently produced and controlled. Objective: Carry out the material balances in the mechanical and thermal operations in obtaining the intermediate product G-0. Materials and Methods: The analysis of the input and output materials mass was conducted for the crude G-0 centrifugation systems, filtration of the suspension to be purified from crude G-0, and centrifugation and drying of the PI G-0. The composition was determined using available techniques and previous research work. For the calculation of the average results of the streams with the Microsoft Office Excel® program 25 batches produced in the years 2016, 2017, 2018 and 2019 were taken into account. Results and Discussion: The material balances per batch in the obtaining of PI G-0 in the systems Centrifugation G-0 Crude, Centrifugation of PI G-0, Filtration and Drying allowed to know the real yield of the desired product for 14 moles of furfural and the losses in the residual streams and due to manufacturing. In the drying operation, the removal of water and wet and dry base solvent was quantified. Conclusions: The material balances in the mechanical and thermal operations of the process of obtaining the intermediate product G-0 allow assuring the consistency of the process. The tests carried out on the specifications: organoleptic characteristics, identification by UV VIS ultraphotometry, melting interval and purity of the product declare the conformity for its use in the production of Furvina.

RESUMEN Introducción: El balance de materiales en la obtención del producto intermedio G-0 garantiza que el producto sea consistentemente producido y controlado. Objetivo: Realizar los balances de materiales en las operaciones mecánicas y térmicas en la obtención del producto intermedio G-0. Materiales y Métodos: Se realizó el análisis de la masa de materiales de entrada y salida para los sistemas centrifugación de G-0 crudo, filtración de la suspensión a purificar de G-0 crudo, centrifugación y secado del PI G-0 y se determinó la composición mediante las técnicas disponibles y trabajos de investigación realizados con anterioridad. Para el cálculo de los resultados promedios de las corrientes con el programa Microsoft Office Excel® se tuvieron en cuenta 25 lotes producidos en los años 2016, 2017, 2018 y 2019. Resultados y Discusión: Los balances de materiales por lote en la obtención del PI G-0 en los sistemas Centrifugación G-0 Crudo, Centrifugación del PI G-0, Filtración y Secado, permitieron conocer el rendimiento real del producto deseado para 14 mole de furfural y las pérdidas en las corrientes residuales y por manufactura. En la operación de secado se cuantificó la eliminación de agua y solvente base húmeda y seca. Conclusiones: Los balances de materiales en las operaciones mecánicas y térmicas del proceso de obtención del producto intermedio G-0 permiten asegurar la consistencia del proceso. Los ensayos realizados a las especificaciones: características organolépticas, identificación por ultrafotometría UV VIS, intervalo de fusión y pureza del producto declaran la conformidad para su uso en la producción de la Furvina.

ABSTRACT Introduction: A water pretreatment plant for hemodialysis through clarification and dechlorination does not offer the expected flow with the required quality, in terms of suspended solids and residual free chlorine, affecting the useful life of reverse osmosis membranes and microfilters. In this work, operational problems are identified and improvements are proposed to guarantee greater efficiency of the installation. Objective: To propose improvements that guarantee the efficiency of water pretreatment for hemodialysis. Materials and Methods: The water flows supplied to the settler and the filter, and water characteristics were determined and compared with those of drinking water and for reverse osmosis. The effects of removal of suspended solids, turbidity, color, residual chorine and required dose of coagulant were established. The load applied to the double layer filter was checked. Results and Discussion: The inlet pressure to the plant does not allow the design flow to be achieved. The applied dose of coagulant is not adequate and alkali should not be added. It was found that the clarification and dechlorination processes are inefficient. Conclusions: Neither the service demand nor the design flow rate is always guaranteed. The required dose of coagulant is 18 mg/L and there is no need to alkalinize the water. The turbidity and color removal efficiencies are 70% and 60.53% respectively, and the suspended solids removal efficiency in the settler is 45.2%. The output turbidity and free chlorine concentration exceed those required for reverse osmosis membranes.

RESUMEN Introducción: Una planta para pretratar agua para hemodiálisis mediante clarificación y decloración no ofrece el caudal esperado con la calidad requerida, en cuanto a sólidos en suspensión y cloro libre residual, afectándose la vida útil de las membranas de ósmosis inversa y microfiltros. En este trabajo se identifican problemas de operación y se proponen mejoras que garanticen mayor eficiencia de la instalación. Objetivo: Proponer mejoras que garanticen la eficiencia del pretratamiento de agua para hemodiálisis. Materiales y Métodos: Se determinaron los caudales abastecidos al sedimentador y a los filtros y características del agua cruda y tratada, se compararon con las de agua potable y para ósmosis inversa. Fueron determinados los efectos de remoción de sólidos suspendidos, turbidez, color, cloro residual y la dosis necesaria de coagulante. Se comprobó la carga aplicada al filtro. Resultados y Discusión: La presión de entrada a la planta no permite lograr el caudal de diseño. La dosis aplicada de coagulante no es adecuada y no debe adicionarse álcali. Son ineficientes los procesos de clarificación y de decloración. Conclusiones: No se garantiza siempre ni la demanda del servicio ni el caudal de diseño. La dosis requerida de coagulante es de 18 mg/L y no se precisa alcalinizar el agua. Las eficiencias de remoción de turbiedad y color son de 70 % y 60,53 % respectivamente, la de sólidos en suspensión en el sedimentador es de 45,2 %. La turbiedad de salida y la concentración de cloro libre superan los exigidos para las membranas de ósmosis inversa.

ABSTRACT Mining environmental liabilities (MEL) are metal-intensive wastes that have the potential to contaminate the surrounding soil, adversely affecting water and air quality, degrading ecosystems, and causing toxic effects on human health. This study used electrochemical treatment as a remediation technique to decontaminate soil affected by MEL. Through a mixed factorial design, the effects of the improvement solutions, acetic acid, and nitric acid, and three distances from the soil with respect to the anode, on the residual concentration and one-dimensional spatial distribution of Pb, Cd, and Zn were investigated. The tests were carried out in triplicate, in acrylic cells, for five days, submitted to 30 V of power, and with nitric acid as cathode fluid. The results showed that nitric acid reduces 4.0, 11.5, and 11.3 times the content of Pb, Cd, and Zn compared to acetic acid, that is, the highest removal percentages of Pb, Zn, and Cd were 40, 34, and 23 %, respectively, when using nitric acid. Moreover, the one-dimensional spatial distribution of metals in the post-treatment soil was not an increasing concentration gradient from the anode region to the cathodic region, but was rather a homogeneous trend. Therefore, using nitric acid as the enhancement fluid confirmed the viability of the electrochemical treatment, although it should be enhanced under other experimental conditions to achieve higher remediation rates.

RESUMEN Los pasivos ambientales mineros (PAM) son residuos con alta carga de metales que tienen el potencial de contaminar el suelo circundante, afectar negativamente la calidad del agua y aire, degradar los ecosistemas y provocar efectos tóxicos en la salud humana. Este estudio utilizó el tratamiento electroquímico como técnica de remediación para descontaminar un suelo afectado por PAM. A través de un diseño factorial mixto se investigó los efectos de las soluciones de mejora, ácido acético y ácido nítrico, y tres distancias del suelo respecto al ánodo, sobre la concentración residual y distribución espacial unidimensional de Pb, Cd y Zn. Los ensayos se realizaron por triplicado, en celdas de acrílico, durante cinco días, sometidos a 30 V de potencia y con ácido nítrico como fluido catódico. Los resultados demostraron que el ácido nítrico reduce 4.0, 11.5 y 11.3 veces el contenido de Pb, Cd y Zn en comparación con el ácido acético, es decir, que los mayores porcentajes de remoción del Pb, Zn y Cd fueron 40, 34 y 23 % respectivamente, al emplear ácido nítrico. Asimismo, la distribución espacial unidimensional de los metales en el suelo después del tratamiento, no fue un gradiente de concentración creciente desde la región anódica hacia la región catódica, sino una tendencia homogénea. Por tanto, emplear ácido nítrico como fluido de mejora confirmó la viabilidad del tratamiento electroquímico, aunque se debería potenciar en otras condiciones experimentales para alcanzar mayores tasas de remediación.

Abstract Transporting live fish is a common practice in fish farming, and is certainly one of the main problems that affect fish homeostasis. In this scenario, the use of natural additives has shown promise in improving fish resistance to adverse situations. This study aimed to assess the impact of Ocimum gratissimum L. essential oil (OGEO) on water quality, hematological parameters, and residue levels in the plasma, fillet, and liver of juvenile piraputanga (Brycon hilarii) during a two-hour transportation period. The fish were divided into plastic bags (4 L) and exposed to three different OGEO concentrations (10, 20, and 30 mg L-1), while a control group received no OGEO (three repetitions each). After the two-hour transportation, blood samples were collected, as well as portions of the fillet and liver for quantifying essential oil compounds, which were also measured in the plasma. Oxygen levels remained high throughout the transportation period, in all groups, while the pH decreased. Hemoglobin, MCHC, and MCH increased in fish exposed to OGEO concentrations of 20 and 30 mg L-1, compared to the control group. However, lymphocyte counts and the concentrations of essential oil compounds in plasma, fillet, and liver increased with higher OGEO concentrations. The use of 10 mg L-1 OGEO in the two-hour transport water is promising to ensure the survival and well-being of Brycon hilarii juveniles (weighing 16 g), showing to be safe and effective. The residual concentration of eugenol the major compound of OGEO in the fillet remains below the maximum limit of the recommended daily intake. farming homeostasis scenario situations L (OGEO quality parameters plasma twohour two hour period 4 ( 10, (10 3 L1, L1 1 , L-1) each. each . each) collected groups decreased Hemoglobin MCHC 2 1, However L- wellbeing being weighing g, g g) effective intake (1

Resumo O transporte de peixes vivos é uma prática comum na piscicultura, e é certamente um dos principais problemas que afetam a homeostase dos peixes e neste cenário o uso de aditivos naturais tem-se mostrado promissor para melhorar a resistência dos peixes frente a situações adversas. Este estudo teve como objetivo avaliar o impacto do óleo essencial de Ocimum gratissimum L. (OEOG) na qualidade de água, perfil hematológico e níveis de resíduos no plasma, filé e fígado de juvenis de piraputanga (Brycon hilarii) durante um período de transporte de duas horas. Os peixes foram divididos em sacos plásticos (4 L) e expostos a três concentrações diferentes de OE OG (10, 20 e 30 mg L-1) enquanto um grupo não recebeu OEOG. Cada grupo com três repetições. Após o transporte de duas horas, foram coletadas amostras de sangue, bem como de filé e do fígado para a quantificação dos compostos do óleo essencial, que também foram mensurados no plasma. Os níveis de oxigênio permaneceram elevados durante todo o período do transporte, em todos os grupos, enquanto o pH diminuiu. A hemoglobina, CHCM e HCM aumentaram nos peixes dos grupos EOOG 20 e 30 mg L-1, em comparação ao grupo controle. No entanto, a contagem dos linfócitos e as concentrações decompostos no plasma, filé e fígado aumentaram com a concentração mais elevada de OEOG. O uso de 10 mg L-1 de OGEO na água de transporte de duas horas é promissor para garantir a sobrevivência e o bem-estar dos juvenis de Brycon hilarii (pesando 16 g), mostrando-se seguro e eficaz. A concentração residual de eugenol, composto majoritário do OGEO no filé, permanece abaixo do limite máximo da ingestão diária recomendada. piscicultura temse tem se adversas L OEOG (OEOG plasma 4 ( 10, (10 2 3 L1 1 repetições sangue diminuiu hemoglobina L1, 1, controle entanto L- bemestar estar pesando g, g , g) mostrandose mostrando eficaz eugenol recomendada (1

MONITORING OF TRIHALOMETHANES (THMs) AND WATER QUALITY FOR PUBLIC SUPPLY IN THE CITY OF CAVALCANTE, GOIÁS. Trihalomethanes (THMs) are organohalogens compounds formed from the reaction between free residual chlorine and natural matter organic (humic substances) present in raw water from surface sources. This study aimed to evaluate the formation of THMs resulting from the application of chlorine for disinfection, in the water treating process for public supply in the city of Cavalcante, GO, located in the region of Chapada dos Veadeiros (Brazil). The results of physical-chemical analyses apparent color, turbidity, pH, free residual chlorine, consumed oxygen, hardness, total alkalinity and THMs demonstrated a positive and strong correlation between the formation of THMs and the hardness of treated water, as well as the chlorine consumed during disinfection process. It was observed an increase in apparent color, turbidity and consumed oxygen in the rainy season. These parameters indicate the presence of organic matter and that present a positive and moderate correlation with the formation of THMs. (THMs CAVALCANTE GOIÁS humic substances sources Cavalcante GO Brazil. Brazil . (Brazil) physicalchemical physical chemical color pH season (Brazil

ABSTRACT Water scarcity and the search for alternative water reuse are challenges faced in the Brazilian semi-arid region. The objective of this study was to predict the risk of clogging of drippers based on water quality attributes and to analyze the effects of industrial residual water and supply water on their hydraulic performance. Two experimental benches were set up in a completely randomized design, in split-split plots, with three replicates. Plots contained the types of water (supply water and reverse osmosis reject), subplots contained the types of non-pressure-compensating drippers (NST - 1.6 L h-1, NSL - 1.6 L h-1 and NDT - 1.7 L h-1) and sub-subplots contained the evaluation times of the distribution uniformity coefficient and relative flow rate (0, 20, 40, 60, 80, 100, 120, 140 and 160 hours). At times 0, 80 and 160 hours, the attributes pH, electrical conductivity, total suspended solids, total dissolved solids, calcium, magnesium, iron and manganese were characterized in both types of water. The data were subjected to descriptive analysis, ANOVA and Tukey test at 5% probability level. In residual water, the attributes that represented a risk of clogging for drippers were pH, electrical conductivity, magnesium and total dissolved solids, while in supply water only pH represented risk. The interaction between types of water and operating time significantly affected both hydraulic performance indicators, but there was no significant effect of the dripper type factor. semiarid semi arid region design splitsplit split plots replicates reject, reject , reject) nonpressurecompensating non pressure compensating NST 16 1 6 1. h1, h1 h 1, h- 17 7 subsubplots sub 0 (0 20 40 60 100 120 14 hours. hours . hours) 8 conductivity solids calcium analysis 5 level indicators factor ( 2 4 10 12

RESUMO A escassez hídrica e a busca por alternativas de reúso da água são desafios enfrentados no semiárido brasileiro. Objetivou-se, com este trabalho, predizer o risco de obstrução de gotejadores por atributos de qualidade da água e analisar os efeitos das águas residual de indústria e de abastecimento no desempenho hidráulico de gotejadores. Para isso, foram montadas duas bancadas experimentais, onde o delineamento utilizado foi o inteiramente casualizado em parcelas subsubdivididas com três repetições. Tendo nas parcelas os tipos de água (água de abastecimento e rejeito da osmose reversa), nas subparcelas os tipos de gotejadores não autocompensantes (NST - 1,6 L h-1, NSL - 1,6 L h-1 e NDT - 1,7 L h-1) e nas subsubparcelas os tempos de avaliação do coeficiente de uniformidade de distribuição e da vazão relativa (0, 20, 40, 60, 80, 100, 120, 140 e 160 horas). Nos tempos 0, 80 e 160 horas efetuou-se a caracterização dos atributos pH, condutividade elétrica, sólidos suspensos totais, sólidos dissolvidos totais, cálcio, magnésio, ferro e manganês nos dois tipos de água. Os dados foram submetidos à análise descritiva, ANOVA e teste de Tukey à 5% de probabilidade. Na água residual os atributos que representaram risco de obstrução para gotejadores foram o pH, condutividade elétrica, magnésio e sólidos dissolvidos totais, enquanto na água de abastecimento somente o pH. A interação tipos de águas e tempo de operação afetou significativamente os dois indicadores de desempenho hidráulico, entretanto não houve efeito significativo do fator tipos de gotejadores. brasileiro Objetivouse, Objetivouse Objetivou se, se Objetivou-se trabalho isso experimentais repetições reversa, reversa , reversa) NST 16 1 6 1, h1, h1 h h- 17 7 0 (0 20 40 60 100 120 14 horas. . horas) 8 efetuouse efetuou pH elétrica totais cálcio descritiva 5 probabilidade ( 2 4 10 12

Resumo O objetivo do presente estudo foi avaliar a capacidade da Pseudomonas aeruginosa, microencapsulada em goma de gelana, para descontaminar águas residuais de laticínios e explorar o potencial reuso das microcápsulas. A P. aeruginosa foi microencapsulada usando a técnica interna de gelificação iônica, empregando goma de gelana de baixo acil como material de parede. As formas livres e microencapsuladas de P. aeruginosa foram inoculadas em 150 mL de água residual estéril e incubadas em um frasco agitado (150 rpm) a 30°C. Posteriormente, o modelo de Baranyi foi utilizado para calcular os parâmetros de crescimento da P. aeruginosa. Ao mesmo tempo, foram determinadas a Demanda Bioquímica de Oxigênio (DBO) e a Demanda Química de Oxigênio (DQO). Os resultados obtidos indicaram que o processo de microencapsulação reduziu a taxa de crescimento do microorganismo encapsulado. No entanto, as bactérias microencapsuladas alcançaram porcentagens de redução de DQO e DBO de 61,54% e 64,05%, respectivamente. Da mesma forma, ao reutilizar as microcápsulas, foram alcançadas porcentagens de remoção superiores a 57,00%. Essas descobertas podem ter implicações significativas para a indústria em termos de redução da contaminação do efluente causada por quantidades substanciais de poluentes. microcápsulas P iônica parede 15 (15 rpm 30C C 30 30°C Posteriormente tempo (DBO DQO. . (DQO) encapsulado entanto 6154 61 54 61,54 6405 64 05 64,05% respectivamente forma 5700 57 00 57,00% poluentes 1 (1 3 (DQO 615 6 5 61,5 640 0 64,05 570 57,00 ( 61, 64,0 57,0 64, 57,

Abstract This study assessed the ability of Pseudomonas aeruginosa, microencapsulated in gellan gum, to decontaminate dairy wastewater and explored the potential reuse of microcapsules. P. aeruginosa was microencapsulated using the internal ionic gelation technique, employing low-acyl gellan gum as the wall material. The free and microencapsulated P. aeruginosa were inoculated into 150 mL of sterile wastewater and incubated in a shaking flask (150 rpm) at 30°C. Subsequently, the Baranyi Model was employed to calculate the growth parameters of P. aeruginosa. Concurrently, Biological Oxygen Demand (BOD) and Chemical Oxygen Demand (COD) were determined. The obtained results indicated that the microencapsulation process reduced the growth rate of the encapsulated microorganism. However, the microencapsulated bacteria achieved COD and BOD reduction percentages of 61.54% and 64.05%, respectively. Similarly, when reusing the microcapsules, removal percentages exceeding 57.00% were achieved. These findings could have significant implications for the industry in terms of reducing effluent contamination caused by substantial amounts of pollutants. microcapsules P technique lowacyl low acyl material 15 (15 rpm 30C C 30 30°C Subsequently Concurrently (BOD (COD determined microorganism However 6154 61 54 61.54 6405 64 05 64.05% respectively Similarly 5700 57 00 57.00 pollutants 1 (1 3 615 6 5 61.5 640 0 64.05 570 57.0 ( 61. 64.0 57. 64.

Resumen (Introducción): Durante años, las aguas residuales de curtiembres han sido vertidas a diversas fuentes de aguas sin control alguno o con tecnologías poco eficientes, lo que genera un impacto en la calidad del agua. (Objetivo): El objetivo del estudio fue evaluar la viabilidad técnico-económica del uso del biopolímero pectina y quitosano para el tratamiento de aguas residuales de curtiembres. (Metodología): Se efectuó la extracción de pectina a partir de la cocona y el quitosano a partir de camarón. Se realizó una prueba de jarras donde se combinó el agua residual y los biopolímeros, la velocidad de agitación fue de 120 rpm y el tiempo de contacto de 1, 2 y 3 h. Se realizaron análisis de pH, demanda química de oxígeno (DQO), demanda bioquímica de oxígeno (DBO), sólidos suspendidos totales (SST) y Cr+6 de las muestras obtenidas. Para la comparación con Valores Máximos Admisibles (VMA), se utilizaron las muestras que mostraron mayor remoción de SST y Cr+6. Para el análisis estadístico de los diferentes tiempos y concentraciones se realizó una prueba ANOVA y de comparación múltiple, para el cotejo de eficiencias entre pectina y quitosano se realizó 1 prueba T de student. (Resultados): En la cantidad de 1 g tanto de quitosano como de pectina se registró una remoción del Cr+6 de 98.33 % y 98.30 % respectivamente, ambos con un tiempo de 1 h. En los sólidos suspendidos totales hubo una reducción del 98 % con 1 h de mezcla para la pectina y 96 % con 3 h de mezcla usando el quitosano. La eficiencia de remoción entre quitosano y pectina no mostraron una diferencia significativa. En la parte económica existe un ahorro de 846.85 USD, mientras que para el quitosano se tendría un ahorro de 807.61 USD. La concentración de parámetros de sólido sedimentable y aceites y grasas se encontró dentro de los VMA. Sin embargo, para sulfuros, DBO y DQO no se cumplió. (Conclusiones): Con el uso de biopolímeros se logró una considerable disminución del Cr+6 y de los SST, además de que ambos resultaron ser muy eficientes. También es una tecnología más rentable económicamente, en comparación con la tecnología empleada por la curtiembre estudiada. Sin embargo, para poder alcanzar los requerimientos de los VMA se deben utilizar algunas tecnologías adicionales.

Abstract (Introduction): For years, wastewater from tanneries has been discharged into various water sources without any control or with inefficient technologies, generating an impact on water quality. (Objective): To evaluate the technical-economic feasibility of the use of the biopolymer pectin and chitosan for the treatment of tannery wastewater. (Methods): Extraction of pectin from cocona and chitosan from shrimp was performed. A jar test was performed where the wastewater and biopolymers were combined, the agitation speed was 120 rpm and the contact time was 1, 2 and 3 h. Analyses of pH, chemical oxygen demand (COD), biochemical oxygen demand (BOD), total suspended solids (TSS) and Cr+6 were performed on the samples obtained. For comparison with Maximum Allowable Values (MAV), the samples that showed the highest TSS and Cr+6 removal were used. For the statistical analysis of the different times and concentrations an ANOVA and multiple comparison test was performed, for the comparison of efficiencies between pectin and chitosan a Student's t-test was performed. (Results): In the amount of 1 g of both chitosan and pectin there was a removal of Cr+6 of 98.33 % and 98.30 % respectively, both with a time of 1 h. In total suspended solids there was a reduction of 98 % with 1 h of mixing for pectin and 96 % with 3 h of mixing using chitosan. The removal efficiency between chitosan and pectin did not show a significant difference. In the economic part there is a saving of 846.85 USD while for chitosan there would be a saving of 807.61 USD. The concentration of settleable solids and oils and fats parameters were found to be within the MAV. However, for sulfides, BOD and COD were not met. (Conclusions): With the use of biopolymers, a considerable decrease in Cr+6 and TSS was achieved, in addition to the fact that both proved to be very efficient. It is also a more economically profitable technology compared to the technology used by the tannery studied. However, in order to meet the requirements of the MAV, some additional technologies must be used.

Abstract Given the scarcity of water resources for agricultural use, it is necessary to promote the use of wastewater for agriculture. The towns of Capulálpam de Méndez and Ixtlán de Juárez in the State of Oaxaca have anaerobic wastewater treatment plants (WWTP). The morphological growth, biomass production and N and P content were evaluated in two forage species -Chenopodium quinoa Willd and Zea mays- irrigated with treated wastewater (TWW). A complete randomized design (CRD) was established in each municipality, given the homogeneity of the soil, using a 2 x 2 factorial arrangement, i.e., two forage crops (Quinoa and corn) and two types of irrigation (fresh water and treated wastewater), with 4 replicates per treatment. Analyses of variance and Tukey mean tests (P≤0.05) were performed for the studied variables. In the soils, the pH level was "moderately acid" to "neutral" (5.1 to 7.3); the EC indicated "negligible effects of salinity"; organic matter was found at intervals of "medium to high", and the texture was sandy clay loam in Ixtlán and clay loam in Capulálpam. Growth variables (plant height, stem diameter, and number of leaves) and biomass were significantly higher in plants irrigated with treated wastewater in both forage crops. Nitrogen and phosphorus contents were significantly higher in quinoa and corn plants receiving TWW. TWW could be an alternative that would help reduce the use of chemical fertilizers, as it is an important source of nutrients in forage crops.

Resumen Ante la escasez del recurso hídrico para el uso agrícola, es necesario promover el uso del agua residual para la agricultura. En las localidades Capulálpam de Méndez e Ixtlán de Juárez, Estado de Oaxaca cuentan con plantas de tratamiento de aguas residuales (PTAR) de tipo anaerobio. Se evaluó el crecimiento morfológico, producción de biomasa y contenido de N y P en dos especies forrajeras: Chenopodium quinoa Willd y Zea mays, regados con agua residual tratada (ART). Se estableció un diseño completo aleatorio (DCA) en cada municipio, dada la homogeneidad del suelo. Con arreglo factorial 2 x 2, esto es, dos cultivos forrajeros (Quinoa y maíz), y dos tipos de riego (agua dulce y agua residual tratada), con 4 repeticiones por tratamiento. Se realizaron análisis de varianza y pruebas de media Tukey (P≤0.05) de las variables estudiadas. En los suelos el nivel de pH fue “moderadamente acido” a “neutro” (5.1 a 7.3); la CE indicó “Efectos despreciables de la salinidad”; Materia orgánica en intervalos de “medio a alto”; y Textura Franco arcilloso arenoso en Ixtlán y Franco arcilloso en Capulálpam. Las variables de crecimiento (altura de planta, diámetro de tallo y número de hojas) y biomasa fueron significativamente mayores en plantas regadas con agua residual tratada en ambos cultivos forrajeros. El contenido de nitrógeno y fósforo fue significativamente mayor en plantas de quinoa y maíz que recibieron ART. El ART podría ser una alternativa que ayude a disminuir el uso de fertilizantes químicos, al ser una fuente importante de nutrimentos en los cultivos forrajeros.

Abstract Introduction: The trout aquacultural activity has gradually increased in Costa Rican highlands. Residual waters from this activity are discarded directly in the rivers without any previous treatment process. Consequently, this activity could severely contaminate the river with bacteria that can affect human health. Objective: To evaluate bacterial contamination from trout aquaculture on Río Savegre, Costa Rica. Methods: We counted total coliforms and Escherichia coli from monthly samples (2015-2018) at three sections of the largest aquacultural development in the upper drainage of the river. We collected samples at the fish ponds entrance, exit and 200 m downwards. Results: We found fewer total coliforms and E. coli in the water collected just at the exit of the fish ponds. We counted more total coliforms in 2016 and 2017, and more E. coli in 2016. Conclusions: Coliform and E. coli counts are high in the river, but, unexpectedly, low in the water discarded from the fish tanks. Perhaps the mucus produced by the trouts or substances released by mosses on the fish tank walls reduce bacterial growth, as suggested by other studies. River pollution appears to come from other sources.

Resumen Introducción: La acuacultura de truchas ha incrementado gradualmente en las tierras altas de Costa Rica. Las aguas residuales de esta actividad son descartadas directamente en los ríos, sin tratamientos previos. Como consecuencia, la actividad truchícola puede contaminar severamente el agua de los ríos con bacterias que pueden afectar la salud humana. Objetivo: Evaluar la contaminación bacteriana por la acuacultura de truchas en el río Savegre, Costa Rica. Métodos: Contamos los coliformes totales y Escherichia coli de muestras mensuales (2015-2018) en tres secciones del proyecto de acuacultura más grande de la cuenca alta del río. Recolectamos las muestras en la entrada de los estanques para las truchas, a la salida, y 200 m hacia abajo. Resultados: Encontramos menos coliformes totales y E. coli en el agua recolectada justo en la salida del agua de los estanques. El número de coliformes totales fue mayor en el 2016 y 2017, y de E. coli en el 2016. Conclusiones: Conteos de coliformes y de E. coli es muy alto en el río, pero inesperadamente, su número disminuye en el agua residual descartada de los estanques. Podría ser que el mucus producido por las truchas o sustancias liberadas del musgo que cubre la pared de los estanques reduzca el crecimiento de bacterias, como se ha sido sugerido en otros estudios. La contaminación del río parece venir de otras fuentes.

Abstract. Because of its large electrochemical window, acetonitrile (MeCN) is one of the most widely used solvents in electrochemistry. It is a suitable solvent for nonaqueous electrolytes that allows studies of cathodic and anodic processes, but electrolyte purification remains challenging. As received, the high-performance liquid chromatography (HPLC) grade is unsuitable for most electroanalytical applications. We present an approach to optimize the purification of HPLC-grade acetonitrile to yield a tetrabutylammonium perchlorate (TBAP)/MeCN electrolyte for experiments in nonaqueous media. We used cyclic voltammetry (CV) to show the background due to impurities and to guide the experimental design to a background current acceptable for CVs of a 1 mM typical concentration of a redox-active molecule. We use 3A molecular sieves, followed by distillation over CaH2 with a final treatment with Al2O3. The optimized procedure yields CH3CN with small background currents, increasing the signal-to-noise ratio and minimizing chemical complications over a wide potential window. Our approach includes discriminating between impurities in the solvent and electrolyte salts; for TBAP, we recrystallize from ethyl acetate and 95 % ethanol. The process and theoretical guidelines apply to other nonaqueous electrolytes dealing with electroactive impurities, including organic molecules, oxygen, and water.

Resumen. El acetonitrilo (MeCN) es uno de los disolventes más utilizados en electroquímica por su amplia ventana electroquímica. Es un disolvente adecuado para electrolitos no acuosos que permite estudiar procesos electroquímicos catódicos y anódicos. Sin embargo, para llevar a cabo estos estudios, es importante considerar la purificación del electrolito que sigue siendo un reto. Tal como se recibe, el acetonitrilo para cromatografía de alto rendimiento (HPLC, por las siglas en inglés) es inadecuado para la mayoría de las aplicaciones electroanalíticas. En este trabajo presentamos un método para optimizar la purificación del acetonitrilo grado HPLC y obtener un electrolito de perclorato de tetrabutilamonio, (TBAP)/MeCN. Utilizamos voltametría cíclica para determinar la corriente de fondo y diseñar una corriente residual aceptable para una concentración típica de 1 mM para una molécula con actividad electroquímica. Utilizamos tamices moleculares 3Å, seguidos de destilación sobre CaH2 y finalizamos con un tratamiento en Al2O3. El procedimiento optimizado produce CH3CN con pequeñas corrientes de fondo, aumentando la relación señal-ruido y minimizando las complicaciones químicas en una amplia ventana de potencial. Nuestro enfoque incluye la discriminación entre las impurezas del disolvente y en las sales del electrolito. Recristalizamos el TBAP con una mezcla de acetato de etilo y etanol al 95 %. El proceso y las directrices teóricas se pueden aplicar a otros electrolitos no acuosos con impurezas electroactivas, como moléculas orgánicas, oxígeno y agua.