O objetivo do presente estudo foi avaliar os efeitos de métodos de processamentos de grãos de milho flint (floculação (MF), 310 g/L x moagem (MM), 1,3 mm de tamanho médio de partícula - TMP) e sua substituição parcial por polpa cítrica peletizada (0, 25, 50 e 75% da MS da dieta) no desempenho e nas características da carcaça de tourinhos terminados em confinamento. Foram utilizados 216 tourinhos da raça Nelore, com peso inicial de 350 kg, alojados em 40 baias coletivas, distribuídos um delineamento em blocos casualizados em arranjo fatorial 2 x 4, perfazendo um total de oito tratamentos (MM0, MM25, MM50, MM75, MF0, MF25, MF50, MF75). O experimento teve duração de 103 dias, após a adaptação dos animais às dietas experimentais, que apresentaram na composição da MS, 12% de bagaço de cana de açúcar in natura (BIN) e 88% de concentrado. Os dados foram analisados através do procedimento MIXED do pacote estatístico SAS, sendo a baia considerada a unidade experimental. Houve interação significativa (P<0,05) para as variáveis IMS, PF, GPD e GPD/IMS entre os tipos de processamento de milho e sua substituição por polpa cítrica na dieta. A substituição do milho floculado por polpa cítrica não afetou (P>0,05) a IMS dos animais, entretanto, houve efeito positivo (P<0,05) da polpa cítrica na IMS dos animais alimentados com milho moído quando a polpa substituiu 50% desse milho (MM50) em comparação com os tratamentos MM0 e MM75. A inclusão de polpa cítrica diminuiu o GPD dos animais nas dietas contendo milho floculado (1,80; 1,52; 1,70; 1,58 kg.cab-1), e aumentou o GPD nas dietas contendo milho moído (1,60; 1,74; 1,85; 1,70 kg.cab-1). A maior eficiência alimentar foi observada nos animais alimentados exclusivamente com milho floculado, seguido pelos animais alimentados com a dieta MF50. Inclusão de polpa cítrica diminuiu a eficiencia alimentar dos animais alimentados com milho floculado (0,222; 0,190; 0,200; 0,184) e não teve nenhum efeito para os animais recebendo dietas contendo milho moído (0,180; 0,176; 0,180; 0,186). A Elg foi maior para as dietas contendo milho floculado (1,73; 1,51; 1,56; 1,45 e 1,42 Mcal kg.MS-1) em comparação com as dietas contendo milho moído (1,42; 1,37; 1,39; 1,44 Mcal kg.MS-1), com um efeito negativo da polpa cítrica nas dietas contendo milho floculado. A espessura de gordura foi maior nos animais alimentados com milho moído em comparação aos animais alimentados com milho floculado (4,4 mm x 5,0 mm). Quando a polpa cítrica substituiu até 50% do milho nas dietas, o teor de amido fecal foi menor para as dietas contendo milho floculado em comparação as dietas contendo milho moído (2,0% x 9,3%). Em conclusão, a floculação aumenta a Elg para bovinos Nelore alimentados com dietas ricas em concentrado, em comparação à moagem fina. A polpa cítrica diminui a Elg nas dietas contendo milho floculado e não apresenta efeitos negativos sobre as dietas contendo milho moído para bovinos da raça Nelore terminados em confinamento. / The effects of flint corn processing (steam flaking, 310 g/l vs. gridding, 1.3 mm GMD) and the partial replacement of corn with citrus pulp (0, 25, 50 or 75%) in feedlot diets were evaluated. A total of 216 Nellore bulls (IBW 350 kg) were allotted to 40 pens and used in a randomized complete block design with a 2 × 4 factorial arrangement of treatments (SF100:CP0; SF75:CP25; SF50:CP50; SF25:CP75; GC100:CP0; GC75:CP25; GC50:CP50; GC25:CP75) for 103-d. The diets contained (% DM) 12% sugar cane bagasse and 88% concentrate. Data was analyzed using mixed procedure of SAS with pens as experimental units. For DMI, ADG, G/F and observed NEg the effects of grain processing, the effects of citrus pulp inclusion in the diets and interactions were significant (P < 0.01). All the diets containing SFC presented less DMI than the GC75:CP25 and the GC50:CP50 diets. Citrus pulp had no effect on DMI of the SFC diets, however it increased DMI when it replaced up to 50% of the GC. Inclusion of CP decreased ADG in the SFC diets (1.80; 1.52; 1.70; 1.58 kg.head-1 and it increased ADG in the GC diets (1.60; 1.74; 1.85; 1.70 kg.head- 1. The greatest G/F was observed for Nellore cattle fed the SF100:CP0 diet followed by the SF50:CP50 diet. Inclusion of citrus pulp decreased G/F of cattle fed SFC (0.222; 0.190; 0.200; 0.184) and had no effect for cattle fed GC diets (0.180; 0.176; 0.180; 0.186). Diet NEg was greater for SFC diets (1.73; 1.51; 1.56; 1.45 Mcal kg.DM-1 than for GC diets (1.42; 1.37; 1.39; 1.44 Mcal kg.DM-1, with a negative effect of CP in the SFC diets. Fat thickness was greater for GC than for SFC diets (4.4 mm vs. 5.0 mm). When CP replaced up to 50% of corn in the diets fecal starch was less for SFC diets than for GC diets (2.0% vs. 9.3%). In conclusion, SFC increases diet NEg for Nellore cattle fed high concentrate diets compared to ground corn. Citrus pulp decreases NEg in SFC diets and has no negative effects on ground corn diets NEg for Nellore cattle.

Foram realizados três experimentos com o objetivo de determinar os efeitos do aumento da PDR da ração por meio do uso de fontes nitrogenadas com diferentes taxas de degradação ruminal. Exp. 1: 28 cordeiros da raça Santa Inês foram utilizados para avaliação do desempenho, características da carcaça e da carne e parâmetros sanguíneos. Além disso, foi avaliada a capacidade do SRNS em predizer o CMS e o GMD dos animais. O farelo de soja foi substituído pela uréia nos teores de 0,7%; 1,4% e 2,1% da MS. Não houve alteração no CMS e nos parâmetros de carcaça e da carne avaliados. Entretanto, o GMD e o peso final dos animais reduziu linearmente na medida que a uréia substituiu o farelo de soja. Por outro lado, a conversão alimentar e a concentração de nitrogênio uréico plasmático apresentou aumento linear com a adição de uréia nas rações. O modelo SRNS apresentou tendência de subestimar o CMS e superstimar o GMD. Exp. 2: 16 cordeiros da raça Santa Inês, canulados no rúmen, foram mantidos em gaiolas metálicas para ensaio de metabolismo e alimentados com as mesmas rações utilizadas no Exp. 1. Não houve diferença no consumo e nos coeficientes de digestibilidade aparente da MS, MO, PB e FDN, bem como no pH ruminal. Houve efeito quadrático para a concentração de acetato e para a produção total de AGCC, enquanto que a concentração de amônia ruminal aumentou linearmente com adição de uréia nas rações. O uso da uréia não alterou o metabolismo do nitrogênio, a excreção urinária de derivados de purina, a produção de nitrogênio microbiano e a eficiência de síntese microbiana. Embora tenha reduzido o GMD em 14,3%, a uréia pode ser utilizada com fonte exclusiva de nitrogênio na alimentação de cordeiros confinados. Exp. 3: 48 ovelhas da raça Santa Inês em lactação foram utilizadas para determinar os efeitos do uso de fontes nitrogenadas com diferentes taxas de degradação ruminal. O farelo de soja, a protenose mais uréia, o refinazil mais uréia ou a uréia foram utilizados como fontes de N, resultando em rações contendo 9,88; 10,4; 12,0 ou 13,4% de PDR, respectivamente. O CMS foi maior, a produção de leite e de leite corrigido para gordura tendeu ser maior (P<0,10) e o teor de gordura do leite foi menor para a ração contendo o farelo de soja. A produção diária de proteína foi maior e o teor de uréia no leite foi menor para as rações contendo o farelo de soja ou a protenose mais uréia como fontes nitrogenadas. A menor eficiência de utilização do N está associada com a alta taxa de degradação da proteína no rúmen, uma vez que as rações contendo 12,0 ou 13,4% de PDR resultaram na redução da produção de proteína do leite, maior concentração de uréia no leite, perda de peso e de condição corporal dos animais. Além disso, o aumento da PDR da ração com a substituição total da proteína verdadeira pela uréia comprometeu o consumo de matéria seca e a produção de ovelhas em lactação. / Three trials were conducted to evaluate the effects of increasing dietary RDP through the use of nitrogen sources with differents rumen degration rates. Trial 1: Twenty-eight Santa Ines ram lambs were used to evaluate the effects of replacing soybean meal by urea in high grain diets on performance, carcass characteristics, meat quality and blood parameters. In addition, were assessed the ability of SRNS to predict dry matter intake and average daily gain of lambs. Soybean meal in control diet was replaced by urea at 0.7; 1.4 e 2.1% on a DM basis. There were no differences among experimental diets for dry matter intake, carcass characteristics and meat parameters. However, average daily gain and final weight decreased linearly as the urea replaced soybean meal. Likewise, feed conversion and plasma urea nitrogen concentration increased linearly with the addition of urea in experimental diets. The SRNS model tended to underestimate dry matter intake and overestimate the average daily gain. Trial 2: Sixteen ruminally cannulated Santa Ines ram lambs were placed in metabolism crates and fed the same TMR used in Trial 1. There was no effect on DM intake, apparent digestibility of dry matter, organic matter, crude protein and neutral detergent fiber, as well as, ruminal pH. Acetate concentration and total short-chain fatty acids concentration showed a quadratic response, while ruminal ammonia concentration increased linearly with urea inclusion to the diet. The nitrogen metabolism, urinary excretion of purine derivatives, microbial nitrogen production and microbial protein synthesis was not influenced with the replacement of soybean meal by urea. Although decreased average daily gain in 14.3%, urea can be used as an exclusive N source in high grain diets fed to feedlot lambs. Trial 3: Forty-eight Santa Ines lactating ewes were used to determine the effects of diets containing N sources with different ruminal degradability. Soybean meal, corn gluten meal plus urea, corn gluten feed plus urea or urea were used as N source, resulting in diets with 9.88, 10.4, 12.0 and 13.4 % of RDP, respectively. Dry matter intake was higher, milk production and fat-corrected milk tended to be higher (P<0.10) and milk fat content was lower for soybean meal diet. Daily milk protein production was higher, and milk urea nitrogen content was lower for diets containing soybean meal or corn gluten meal plus urea as N source. The lower N efficiency was associated with high protein ruminal degradation rate, once the diets containing 12.0 or 13.4% RDP resulted in reduced milk protein production, higher milk urea concentration and loss of weight and body condition score. Furthermore, a higher RDP with the total replacement of the true protein by urea affected dry matter intake and milk production of lactating ewes.

Previous studies have shown favourable properties for papaya bast fibres, with a Young's modulus of up to 10 GPa and a tensile strength of up to 100 MPa. Because the fibres remain as residues on papaya plantations across the tropics in large quantities, their use in the making of green composites would seem to be worthy of consideration. This study aims to show that such composites can have very suitable mechanical properties, comparable to or even better than the common wood plastic composites (WPCs), and as such, represent a promising raw material for composites and a low-cost alternative to wood.

Tesis por compendio / [ES] Actualmente, la sostenibilidad del sector porcino depende de su capacidad para responder a la elevada demanda de productos ganaderos derivada del crecimiento de la población, adaptándose a los cambios en los contextos económico y político, y mejorando su rendimiento medioambiental mediante la mitigación de su impacto ambiental. En este contexto, el uso de subproductos agroindustriales ofrece materias primas alternativas en producción animal, con una menor carga ambiental asociada, en forma de piensos para el ganado, fuente de compuestos bioactivos o materias primas útiles en la producción de bioenergía. Esta tesis doctoral pretende evaluar el uso de subproductos agroindustriales mediterráneos como ingredientes en piensos para el ganado porcino o como co-substratos para la producción de biogás. Con este objetivo, se diseñaron y realizaron cuatro ensayos para evaluar el uso de subproductos de la industria del aceite de oliva y del zumo de naranja en alimentación porcina, evaluando su valor nutricional y las consecuencias de su inclusión sobre el rendimiento y la salud de los animales, la calidad del producto final y las emisiones de gases de los purines. Además, se realizó un ensayo para evaluar el efecto de cuatro sustratos agrícolas sobre el potencial bioquímico de metano (BMP) en co-digestión anaerobia con purines. Los resultados obtenidos a partir de los ensayos de valor nutricional indican que las tortas de aceituna y las pulpas de naranja ensayadas pueden ser incluidas en la dieta con cambios asociados en la excreción de nutrientes que conducen a modificaciones en las emisiones potenciales de amoníaco y BMP de los purines. En cuanto a los subproductos de la torta de aceituna, el ensayo de valor nutricional con tortas de aceituna crudas (COC) y parcialmente desgrasadas (PDOC) mostró que ambas tortas son fuentes apreciables de fibra insoluble, pero tienen un valor energético limitado (11.2 y 7.4 MJ/kg MS para COC y PDOC respectivamente) y un bajo valor como fuente de proteínas. En cambio, las pulpas de naranja deshidratadas (DOP) y ensilada secada al sol (ESDOP) ensayadas son una fuente de energía relevante (14.2 y 13.2 MJ/kg MS para DOP y ESDOP respectivamente) con valor añadido debido a su contenido en fibra soluble. En los ensayos de emisiones in vitro, los subproductos ensayados generaron una disminución en la excreción de N en la orina y, en el caso de la pulpa de aceituna, un aumento de la excreción de materia seca en heces. La emisión de amoniaco por kg de purín disminuyó con la inclusión de torta de aceituna y pulpa de naranja, mientras que el BMP por animal y día se vio negativamente afectado por la inclusión de torta de aceituna obteniendo un mayor BMP con estos subproductos. En cuanto a los ensayos de rendimientos productivos, la PDOC y la DOP pueden incluirse en la dieta hasta 120 y 240 g/kg respectivamente, sin efectos negativos en el caso de la PDOC y efectos menores para la DOP sobre los rendimientos productivos, la composición corporal y la calidad de la canal. La inclusión de PDOC y DOP no afectó a los recuentos microbianos ni al volumen, la composición y la emisión global de gases de los purines. Además, se observaron efectos beneficiosos sobre la grasa subcutánea con la inclusión de PDOC, mejorando su concentración en ácido oleico. La co-digestión anaerobia de subproductos agrícolas y purines mejora el BMP de la mezcla de sustratos en comparación con la digestión única de purines. Se obtuvieron mayores valores de BMP con la adición de los sustratos agrícolas, lo que confirma el mejor rendimiento de los sistemas en co-digestión a niveles de inclusión adecuados. Las combinaciones con tomate, pimiento y melocotón al nivel de inclusión 3 (50% de SV) alcanzaron el mayor BMP. Esto supuso un incremento del BMP del 41% con tomate, 44% con pimiento, 28% con melocotón y 12% con caqui. Los sustratos vegetales mostraron un mayor contenido en lípidos, prote / [CAT Actualment, la sostenibilitat del sector porcí depèn de la seua capacitat per a respondre a l'elevada demanda de productes ramaders derivada del creixement de la població, adaptant-se als canvis en els contextos econòmic i polític, i millorant el seu rendiment mediambiental mitjançant la mitigació del seu impacte ambiental. En aquest context, l'ús de subproductes agroindustrials ofereix matèries primeres alternatives en producció animal, amb una menor càrrega ambiental associada, en forma de pinsos per al bestiar, font de compostos bioactius o matèries primeres útils en la producció de bioenergia. Aquesta tesi doctoral pretén avaluar l'ús de subproductes agroindustrials mediterranis com a ingredients en pinsos per al bestiar porcí o com co-substrats per a la producció de biogàs. Amb aquest objectiu, es van dissenyar i realitzar quatre assajos per a avaluar l'ús de subproductes de la indústria de l'oli d'oliva i del suc de taronja en alimentació porcina, avaluant el seu valor nutricional i les conseqüències de la seua inclusió sobre el rendiment i la salut dels animals, la qualitat del producte final i les emissions de gasos dels purins. A més, es va realitzar un assaig per a avaluar l'efecte de quatre substrats agrícoles sobre el potencial bioquímic de metà (BMP) en co-digestió anaeròbia amb purins. Els resultats obtinguts a partir dels assajos de valor nutricional indiquen que les trotes d'oliva i les polpes de taronja assajades poden ser incloses en la dieta amb canvis associats en l'excreció de nutrients que condueixen a modificacions en les emissions potencials d'amoníac i BMP dels purins. Quant als subproductes de la torta d'oliva, l'assaig de valor nutricional amb tortes d'oliva crues (COC) i parcialment desengreixades (PDOC) va mostrar que totes dues coques són fonts apreciables de fibra insoluble, però tenen un valor energètic limitat (11.2 i 7.4 MJ/kg MS per a COC i PDOC respectivament) i un baix valor com a font de proteïnes. En canvi, les polpes de taronja deshidratades (DOP) i ensitjada assecada al sol (ESDOP) assajades són una font d'energia rellevant (14.2 i 13.2 MJ/kg MS per a DOP i ESDOP respectivament) amb valor afegit a causa del seu contingut en fibra soluble. Pel que fa als assajos d'emissions in vitro, els subproductes assajats van generar una disminució en l'excreció de N en l'orina i, en el cas de la polpa d'oliva, un augment de l'excreció de matèria seca en femtes. L'emissió d'amoníac per kg de purí va disminuir amb la inclusió de torta d'oliva i polpa de taronja, mentre que el BMP per animal i dia es va veure negativament afectat per la inclusió de torta d'oliva obtenint un major BMP amb aquests subproductes. Quant als assajos de rendiments productius, la PDOC i la DOP poden incloure's en la dieta fins a 120 i 240 g/kg respectivament, sense efectes negatius en el cas de la PDOC i efectes menors per a la DOP sobre els rendiments productius, la composició corporal i la qualitat de la canal. La inclusió de PDOC i DOP no va afectar els recomptes microbians ni al volum, la composició i l'emissió global de gasos dels purins. A més, es van observar efectes beneficiosos sobre el greix subcutani amb la inclusió de PDOC, millorant la seua concentració en àcid oleic. La co-digestió anaeròbia de subproductes agrícoles i purins millora el BMP de la mescla de substrats en comparació amb la digestió única de purins. Es van obtenir majors valors de BMP amb l'addició dels substrats agrícoles, la qual cosa confirma el millor rendiment dels sistemes en co-digestió a nivells d'inclusió adequats. Les combinacions amb tomaca, pimentó i bresquilla al nivell d'inclusió 3 (50% de SV) van aconseguir el major BMP. Això va suposar un increment del BMP del 41% amb tomaca, 44% amb pimentó, 28% amb bresquilla i 12% amb caqui. Els substrats vegetals van mostrar un major contingut en lípids, proteïnes, lignina i cel·lulosa que els substrats de fruita. / [EN] Nowadays the sustainability of the pig sector relies on its capability to respond to the increasing demands for livestock products that are arising from population growth, adapting to changes in the economic and policy contexts, and improving its environmental performance through the mitigation of its impact on climate. In this framework, the use of the agro-industrial by-products offers potential alternative raw materials for animal production with a lower associated environmental burden in the form of feedstuffs for livestock, source of bioactive compounds or raw materials useful in bioenergy production. This PhD thesis aims to evaluate the use of Mediterranean agro-industrial by-products as feed ingredients for pigs or co-substrates for biogas production. To fulfil these objectives, four trials were designed and conducted to evaluate the use of olive oil and orange juice industry by-products in swine nutrition, assessing its nutritional value and the consequences of its inclusion in the diet on animals' performance and health, final product quality traits and gas emissions associated to the pig slurry. Additionally, one more trial was conducted to evaluate the effect of four agricultural substrates (tomato, pepper, peach and kaki) on the biochemical methane potential (BMP) in anaerobic co-digestion with pig slurry, focusing on the type of substrate and its inclusion level on the final substrate's mixture. The results presented in this PhD Thesis from the nutritional value assays indicate that the olive cakes and orange pulps tested can be potentially included in pig diets with associated changes in urine and faeces nutrients excretion that leads to modifications in the potential ammonia and BMP emissions from slurries. Concerning olive cake by-products, the nutritional value assay designed to test the crude (COC) and partially defatted (PDOC) olive cakes showed that they are appreciable sources of insoluble fibre but have limited energy value (11.2 and 7.4 MJ/kg DM for COC and PDOC respectively) and a low value as protein source. On the contrary, the dehydrated (DOP) and ensiled sun-dried (ESDOP) orange pulps tested are a relevant energy source (14.2 and 13.2 MJ/kg DM for DOP and ESDOP respectively) with added value in terms of SF concentration. With respect to the in vitro potential ammonia and BMP emissions assays, the by-products tested led to a decreased N excretion in urine and, in the case of the OC, increased DM excretion in faeces. The ammonia emission per kg of slurry decreased with the inclusion of olive cake and orange pulp, whereas the BMP per animal and per day was negatively affected by the inclusion of olive cake obtaining higher BMP with these by-products. Regarding the performance assays, the PDOC and the DOP may be included in balanced pig diets at rates of up to 120 and 240 g/kg respectively, without negative effects in the case of PDOC and minor effects for DOC on growth performance, body composition and carcass quality traits. Contrary to what was expected, the inclusion of PDOC and DOP did not affect microbial counts nor excreta volume, composition and global gas emission from the slurry. Additionally, beneficial effects on subcutaneous fat were observed with the inclusion of PDOC, improving its oleic acid concentration. The anaerobic co-digestion of agricultural by-products and pig slurry improves the BMP from the mixture compared to only pig slurry anaerobic digestion. Higher BMP values were obtained with increasing addition of agricultural substrate, confirming the better performance of co-digestion systems at adequate inclusion levels. In fact, combinations with tomato, pepper and peach at inclusion level 3 (50% of VS) achieved the highest BMP. This resulted in an increase in BMP of 41% with tomato, 44% with pepper, 28% with peach and 12% with kaki. Vegetable substrates (pepper and tomato) showed higher lipid, protein, lignin and cellulose content than fruit substrates (kaki and peach). / Ferrer Riera, P. (2021). Valorisation of Mediterranean agroindustrial by-products in pig production as feed and anaerobic co-digestion of slurry [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/171747 / TESIS / Compendio

<p>Swimming is the second most common form of recreational activity in the U.S. Swimming pool water and air quality should be maintained to allow swimmers, pool employees, and spectators to use the pool facility safely. One of the major concerns regarding the health of swimmers and other pool users is the formation of disinfection by-products (DBPs) in swimming pools. Previous research has shown that volatile DBPs can adversely affect the human respiratory system. DBPs are formed by reactions between chlorine and other compounds that are present in water, most of which are introduced by swimmers, including many that contain reduced nitrogen. Some of the DBPs formed in pools are volatile, and their transfer to the gas phase in pool facilities is promoted by mixing near the air/water interface, caused by swimming and pool features.</p> <p><a>Swimming pool water treatment processes can play significant roles in governing water and air quality.</a> Thus, it is reasonable to hypothesize that water and air quality in a swimming pool facility can be improved by renewing or enhancing one or more components of water treatment.</p> <p>The first phase of the study was designed to identify and quantify changes in water and air quality that are associated with changes in water treatment at a chlorinated indoor pool facility. Reductions of aqueous NCl₃concentration were observed following the use of secondary oxidizer with its activator. This inclusion also resulted in significant decreases in the concentrations of cyanogen chloride (CNCl) and dichloroacetonitrile (CNCHCl₂) in pool water. The concentration of urea, a compound that is common in swimming pools and that functions as an important precursor to NCl₃ formation, as well as a marker compound for introduction of contaminants by swimmers, was also reduced after the addition of activator.</p> <p>The second phase of this study involved field measurements to characterize and quantify the dynamic behavior of indoor air quality (IAQ) in indoor swimming pool facilities, particularly as related to volatile compounds that are transferred from swimming pool water to air. Measurements of water and air quality were conducted before, during, and after periods of heavy use at several indoor pool facilities. The results of a series of measurements at different swimming pool facilities allowed for examination of the effects of swimmers on liquid-phase DBPs and gas-phase NCl₃. Liquid-phase NCl₃ concentrations were observed to gradually increase during periods of high swimmer numbers (<i>e.g.</i>, swimming meets), while liquid-phase CHCl₃ concentration was nearly constant in the same period. Concentrations of urea displayed a steady increase each day during these periods of intensive use. In general, the highest urea concentrations were measured near the end of each swimming meet. </p> <p>Measurements of IAQ dynamics during phase 2 of the study demonstrated the effects of swimmers on the concentrations of gas-phase NCl₃and CO₂, especially during swimming meets. The measured gas-phase NCl₃ concentration often exceeded the suggested upper limits of 300 µg/m³ or 500 µg/m³during swimming meets, especially during and immediately after warm-up periods, when the largest numbers of swimmers were in the pool. Peak gas-phase NCl₃ concentrations were observed when large numbers of swimmers were present in the pools; measured gas-phase concentrations were as high as 1400 µg/m³.Concentrations of gas-phase NCl₃ rarely reached above 300 µg/m³ during regular hours of operation. Furthermore, the types of swimmers were shown to affect the transfer of volatile compounds, such as NCl₃, from water to airin pool facilities. In general, adult competition swimmers promoted more rapid transfer of these compounds than youth competition swimmers or adult recreational swimmers. The measured gas-phase CO₂ concentration often exceeded 1000 ppm_v during swimming meets, whereas the gas-phase CO₂ concentration during periods of non-use of the pool tended to be close to the background (ambient) CO₂ concentration or slightly more than 400 ppm_v. This phenomenon was largely attributed to the activity of swimmers (mixing of water and respiratory activity) and the normal respiratory activity of spectators. </p> <p>IAQ models for gas-phase NCl₃ and CO₂ were developed to relate the characteristics of the indoor pool environment to measurements of IAQ dynamics. Several assumptions were made to develop these models. Specifically, pool water and indoor air were assumed to be well-mixed. The reactions that were responsible for the formation and decay of the target compounds were neglected. Two-film theory was used to simulate the net mass-transfer rate of volatile compounds from the liquid phase to the gas phase. Advective transport into and out of the air space of the pool were accounted for. The IAQ model was able to simulate the dynamic behavior of gas-phase NCl₃ during regular operating hours. Predictions of gas-phase NCl₃ dynamics were generally less accurate during periods of intensive pool use; however, the model did yield predictions of behavior that were qualitatively correct. Strengths of the model include that it accounts for the factors that are believed to have the greatest influence on IAQ dynamics and is simple to use. Model weaknesses include that the model did not account liquid-phase reactions that are responsible for formation and decay of the target compounds. The IAQ model for NCl₃ dynamics could still be a useful tool to form the basis for recommendations regarding the design and operation of indoor pool facilities so as to optimize IAQ.</p><p>Measurements of CO₂ dynamics indicated qualitatively similar dynamic behavior as NCl₃. Because of this, it was hypothesized that CO₂ may represent a surrogate for NCl₃ for monitoring and control of IAQ dynamics. To examine this issue in more detail, a conceptually similar model of CO₂dynamics was developed and applied. The model was developed to allow for an assessment of the relative contributions of liquid®gas transfer and respiration by swimmers and spectators to CO₂ dynamics. The results of this modeling effort indicated that the similarity of CO₂ transfer behavior to NCl₃ may allow use of CO₂ as a surrogate during periods with few to no spectators in the pool; however, when large numbers of spectators are present, the behavior of CO₂ dynamics may not be representative of NCl₃ dynamics because of spectator respiration.</p><p></p> <br>

<p>Cilj ovog rada bio je da se u laboratorijskim uslovima ispitaju efekti odabranih<br />unapredenih procesa oksidacije (Fenton proces, ozonizacija, TiO2-katalizovana ozonizacija,<br />perokson proces i TiO2-katalizovan perokson proces) i koagulacije na sadržaj i strukturu<br />prirodnih organskih materija u vodi, kao prekursora dezinfekcionih nusprodukata hlora.<br />Karaterizacija POM frakcionisanjem pre i nakon navedenih oksidacionih tretmana i<br />koagulacije izvr&scaron;ena je u cilju ispitivanja mehanizama oksidacije i uklanjanja POM, kao i<br />utvrdivanja promene reaktivnosti prekursorskog materijla DBP (trihalometana i halosircetnih<br />kiselina, kao najvi&scaron;e zastupljenih DBP, i haloacetonitrila, hlorpikrina i haloketona, kao<br />nedovoljno istraženih, visoko prioritetnih &bdquo;DBP u razvoju&ldquo;).<br />Analizom hemijskih karakteristika prirodnog matriksa utvrdeno je da voda sadrži<br />visoke koncentracije prirodnih organskih materija (DOC sirove iznosi 9,92&plusmn;0,87 mg/L) uz<br />dominaciju materija hidrofobnog karaktera (14% huminskih i 65% fulvinskih kiselina). U<br />slucaju sintetickog matriksa (sadržaj DOC 11,2&plusmn;0,37 mg/L) zastupljena je samo frakcija<br />huminske kiseline, te je iz tog razloga sinteticki matriks znatno hidrofobniji u odnosu na<br />prirodni. Veci stepen hidrofobnosti sintetickog matriksa u poredenju sa prirodnim matriksom,<br />rezultovao je i vecim sadržajem prekursora najzastupljenijih dezinfekcionih nusprodukata<br />hlora, THM i HAA. Vrednosti za PFTHM iznose 438&plusmn;88,2 &mu;g/L za prirodni matriks,<br />odnosno 3646&plusmn;41,3 &mu;g/L za sinteticki matriks, dok PFHAA prirodnog matriksa iznosi<br />339&plusmn;68,9 &mu;g/L, odnosno 559&plusmn;20,5 &mu;g/L za sinteticki matriks. Sadržaj HAN, CP i HK je<br />znatno niži u poredenju sa prekursorima THM i HAA. PFHAN iznosi 3,65 &mu;g/L za prirodni,<br />odn. 7,98 &mu;g/L za sinteticki matriks, dok prekursori CP nisu detektovani. Prekursori HK su<br />zastupljeni samo u strukturi POM prirodnog matriksa i PFHK iznosi 46,9&plusmn;5,08 &mu;g/L.<br />Hidrofoban materijal, kao dominantan u strukturi POM ispitivanih matriksa, je ujedno i<br />osnovni prekursorski materijal THM i HAA, dok su prekursori haloacetonitrila i haloketona u<br />navecoj meri zastupljeni u hidrofilnoj frakciji.<br />Ispitivanjem uticaja Fenton procesa na sadržaj POM, pri optimalnim reakcionim<br />uslovima (pH 5, reakciono vreme od 15 min. i brzina me&scaron;anja 30 o/min), postignuto je u<br />zavisnosti od primenjene doze Fe2+, molarnog odnosa Fe2+ i H2O2 i matriksa 80-95%<br />smanjenja saržaja DOC, 70-99% PFTHM, 37-92% PFHAA. Kao posledica uklanjanja POM<br />oksidaciojom i koagulacijom, zabeležene su blage fluktuacije u sadržaju prekursora HAN, CP<br />i HK.<br />Ispitivanjem uticaja ozonizacije u vodi pri razlicitim pH na sadržaj i strukturu POM<br />utvrdeno je da je ozonizacija u baznoj sredini efikasnija za uklanjanje POM u odnosu na<br />ozonizaciju u kiseloj sredini. Katalizovanje procesa ozonizacije primenom TiO2 u vodi<br />razlicitim pH unapreduje smanjenje sadržaja kako ukupnih organskih materija, tako i<br />specificnih prekursora DBP u poredenju sa ozonizacijom. Najefikasnije smanjenje sadržaja<br />POM postignuto je TiO2-O3 procesa u baznoj sredini primenom 3,0 mg O3/mg DOC i 1,0 mg<br />TiO2/L (30% DOC, 92-100% PFTHM, PFHAA, PFHAN i PFHK). TiO2-O3 proces pri svim<br />pH vrednostima produkuje manji sadržaj CP u odnosu na ozonizaciju. Veca efikasnost<br />primenjenih procesa u smanjenju sadržaja POM sintetickog matriksa u odnosu na prirodni<br />ukazuju da je frakcija huminske kiseline podložnija oksidacionom tretmanu u odnosu na<br />fulvinsku, kao dominantnu frakciju POM prirodnog matriksa. Kada je u pitanju mehanizam<br />oksidacije POM ispitivanih matriksa, primenom ozonizacije i TiO2-O3 procesa, pri svim pH<br />postignuta je potpuna oksidacija frakcije huminske kiseline do fulvinske kiseline i hidrofilnih<br />jedinjenja. U slucaju ozonizacije, sa povecanjem pH vrednosti sredine, usled povecane<br />produkcije hidroksil radikala iz ozona, povecao se i udeo odnosno sadržaj DOC u hidrofilnoj<br />frakciji ozonirane vode (86%-90%). Raspodela DOC nakon TiO2-O3 procesa pri svim pH<br />vrednostima je oko 70% i 50% u hidrofilnoj frakciji prirodnog i sintetickog matriksa, redom.<br />Frakcija koja se dominantno formira nakon navedenih oksidacionih tretmana je hidrofilna nekisela<br />frakcija. Frakcionisanjem POM nakon oksidacionih tretmana je utvrdeno da su<br />prekursori THM i HAA kako hidrofobne aromaticne strukture, tako i hidrofilna polarna<br />jedinjenja, dok je najreaktivniji prekursorski materijal HAN, CP i HK sadržan u hidrofilnoj<br />frakciji POM.<br />Uvodenjem H2O2 u proces ozonizacije (O3/H2O2 i iO2-O3/H2O2) u slabo baznoj<br />sredini (pH 7-7,5) postignut je jo&scaron; veci stepen oksidacije POM i povecanje udela hidrofilnih<br />struktura (oko 88%) ispitivanih matriksa u odnosu na ozonizaciju i iO2-O3 (oko 70%),<br />primenom 3,0 mg O3/mg DOC; O3:H2O2=1:1 i 1,0 mg iO2/L. Povecanje sadržaja prekursora<br />THM i HAA samo u slucaju prirodnog amtriksa posledica je povecanja reaktivnosti frakcije<br />fulvinske kiseline nakon O3/H2O2 i iO2-O3/H2O2 procesa, u kojoj su ujedno i prekursori HK<br />najzastupljeniji. Najveci sadržaj azotnih DBP (HAN i CP) sadrži hidrofilna frakcija POM.<br />Ispitivanjem kombinovanih procesa ozonizacije i TiO2-O3 i koagulacije utvrdeno je da<br />oksidacioni tretmani imaju pozitivne efekte u uklanjaju POM koagulacijom. Maksimalna<br />efikasnost smanjenja sadržaja DOC od 32% postignuto je primenom 3,0 mg O3/mg DOC i<br />200 mg FeCl3/L, dok su ne&scaron;to niže doze ozona pogodne za uklanjanje prekursora DBP (80-<br />89% PFTHM, PFHAA, PFHAN i PFHK, primenom 0,7-1,0 mg O3/mg DOC i 200 mg<br />FeCl3/L). Prekursori CP koji se formiraju ozonizacijom zaostaju u vodi nakon koagulacije.<br />Rezultati dobijeni tokom istraživanja ukazuju da se primenom razlicitih oksidacionih i<br />unapredenih oksidacionih procesa može smanjiti sadržaj POM i prekursora DBP do<br />odredenog stepena. Kao najefikasniji u uklanjaju kako ukupnih organskih materija, tako i<br />specificih prekursora DBP se pokazao Fenton proces. Kada su u pitanju unapredeni procesi<br />oksidacije zasnovani na primeni ozona, uvodenje katalizatora ili H2O2 kao oksidanta u proces<br />ozonizacije, kao i odabir optimalne pH vrednosti procesa može unaprediti oksidabilnost<br />organskih molekula. Pri tom, poznavanje mehanizama oksidacije POM iz razlicitih izvora<br />primenom ozona i/ili hidroksil radikala, kao i mehanizma uklanjanja POM koagulacijom<br />može se primeniti za odabir i optimizovanje odgovarajuceg procesa u tretmanu vode za pice,<br />a u zavisnosti od kvaliteta sirove vode.</p> / <p>The aim of this work was to examine under laboratory conditions the effects of<br />certain advanced oxidation processes (Fenton process, ozonation, TiO2-catalyzed ozonation,&nbsp;peroxone process and TiO2-catalyzed peroxone process) and coagulation on the content,&nbsp;structure and role of natural organic matter in water as the precursors of chlorine disinfection&nbsp;byproducts. The NOM was characterized by fractionation before and after these oxidation&nbsp;treatments and coagulation, in order to investigate NOM oxidation mechanisms and identify&nbsp;the changes in the reactivity of DBP precursor material (trihalomethanes and haloacetic acids,&nbsp;as the most abundant DBP, and haloacetonitriles, chloropicrin and haloketones, as underresearched,&nbsp;high priority &ldquo;emerging DBP&rdquo;).&nbsp;Through analysis of the chemical characteristics of the natural matrix, it was found&nbsp;that the water contains high concentrations of natural organic matter (raw water DOC was&nbsp;9.92 &plusmn; 0.87 mg/L) dominated by substances with a hydrophobic character (14% humic and&nbsp;65% fulvic acids). The synthetic matrix studied (DOC content of 11.2 &plusmn; 0.37 mg/L)&nbsp;contained only the humic acid fraction, and was therefore significantly more hydrophobic&nbsp;compared to the natural one. The greater degree of hydrophobicity in the synthetic matrix&nbsp;relative to the natural matrix resulted in a higher content of precursors of the most frequent&nbsp;chlorine disinfection byproducts, THM and HAA. The THMFP of the natural matrix was&nbsp;438&plusmn;88.2 mg/L, compared to 3646&plusmn;41.3 mg/L for the synthetic matrix, while the HAAFP of&nbsp;the natural matrix was 339&plusmn;68.9 mg/L, compared to 559&plusmn;20.5 mg/L for the synthetic matrix.&nbsp;The contents of HAN, CP, and HK precursors were much lower than the THM and HAA&nbsp;precursors. HANFP were 3.65 mg/L for natural, and 7.98 mg/L for the synthetic matrix,&nbsp;whilst CP precursors were not detected. HK precursors were present only in the structure of&nbsp;the natural NOM matrix, with a HKFP of 46.9&plusmn;5.08 mg/L. Hydrophobic material, as the&nbsp;dominant structure in the investigated NOM matrix, is the basic precursor material of THM&nbsp;and HAA, while the precursors of haloacetonitriles and haloketones are represented mostly in&nbsp;the hydrophilic fraction.<span style="font-size: 12px;">Whilst examining the influence of the Fenton process on the NOM content, under&nbsp;</span><span style="font-size: 12px;">optimal reaction conditions (pH 5, reaction time of 15 min and stirring speed of 30 rpm),&nbsp;</span><span style="font-size: 12px;">depending upon the applied dose of Fe2+, the molar ratio of Fe2+ and H2O2, and the matrix,&nbsp;</span><span style="font-size: 12px;">reductions in the DOC content of 80-95%, in the THMFP of 70-99%, and in the HAAFP of&nbsp;</span><span style="font-size: 12px;">37-92%, were achieved. As a result of removing NOM by oxidation and coagulation, mild&nbsp;</span><span style="font-size: 12px;">fluctuations in the contents of HAN, CP and HK precursors were recorded.&nbsp;</span><span style="font-size: 12px;">The investigation into the effects of ozonation at different pH levels on the content&nbsp;</span><span style="font-size: 12px;">and structure of NOM has shown that ozonation under alkaline conditions is more effective at&nbsp;</span><span style="font-size: 12px;">removing NOM than ozonation under acidic conditions. Catalyzing the ozonation process&nbsp;</span><span style="font-size: 12px;">using TiO2 in water with different pH promotes the reduction of both total organic matter and&nbsp;</span><span style="font-size: 12px;">specific DBP precursors in comparison with ozonation alone. The most effective NOM&nbsp;</span><span style="font-size: 12px;">reduction was achieved using the TiO2-O3 process in alkaline conditions using 3.0 mg O3/mg&nbsp;</span><span style="font-size: 12px;">DOC and 1.0 mg TiO2/L (30% DOC, 92-100% THMFP, HAAFP, HANFP and HKFP). The&nbsp;</span><span style="font-size: 12px;">TiO2-O3 process produces lower amounts of CP at all pH values, relative to ozonation. The&nbsp;</span><span style="font-size: 12px;">applied processes showed increased efficacy in reducing the NOM content of the synthetic&nbsp;</span><span style="font-size: 12px;">matrix compared with the natural matrix, which shows that the humic acids fraction is more&nbsp;</span><span style="font-size: 12px;">susceptible to oxidation treatments than the fulvic acids which are the dominant faction of the&nbsp;</span><span style="font-size: 12px;">natural NOM matrix. Regarding the NOM oxidation mechanism in the investigated matrices,&nbsp;</span><span style="font-size: 12px;">using ozonation and the TiO2-O3 process, complete oxidation of the humic acid fraction to&nbsp;</span><span style="font-size: 12px;">fulvic acids and hydrophilic compounds was achieved at all pH levels. In the case of&nbsp;</span><span style="font-size: 12px;">ozonation, increasing the pH in the matrix lead to an increase in hydroxyl radicals production&nbsp;</span><span style="font-size: 12px;">from ozone, and the proportion or content of DOC in the hydrophilic fraction of ozonated&nbsp;</span><span style="font-size: 12px;">water (86%-90%) increased. The distribution of DOC after the TiO2-O3 process at all pH&nbsp;</span><span style="font-size: 12px;">values was about 70% and 50% in the hydrophilic fraction of the natural and synthetic&nbsp;</span><span style="font-size: 12px;">matrices, respectively. The dominant fraction formed after the oxidation treatments was the&nbsp;</span><span style="font-size: 12px;">hydrophilic non-acid fraction. By NOM fractionation after the oxidation treatments, it was&nbsp;</span><span style="font-size: 12px;">shown that the THM and HAA precursors are hydrophobic aromatic structures and&nbsp;</span><span style="font-size: 12px;">hydrophilic polar compounds, whilst the most reactive precursor materials for HAN, CP and&nbsp;</span><span style="font-size: 12px;">HC are contained in the hydrophilic NOM fraction.&nbsp;</span><span style="font-size: 12px;">Introducing H2O2 into the ozonation process (O3/H2O2 and iO2-O3/H2O2) in weak&nbsp;</span><span style="font-size: 12px;">basic conditions (pH 7 to 7.5) enhances further the degree of NOM oxidation and increases&nbsp;</span><span style="font-size: 12px;">the proportion of hydrophilic structures (88%) in the examined matrices in comparison to&nbsp;</span><span style="font-size: 12px;">ozonation and iO2-O3 (about 70%), using 3.0 mg O3/mg DOC; O3:H2O2=1:1 and 1.0 mg&nbsp;</span><span style="font-size: 12px;">iO2/L. An increase in the THM and HAA precursor contents occurred in the case of the&nbsp;</span><span style="font-size: 12px;">natural matrix as a result of the increased reactivity of the fulvic acid fraction after the&nbsp;</span><span style="font-size: 12px;">O3/H2O2 and iO2-O3/H2O2 processes, and HK precursors were also present. The highest&nbsp;</span><span style="font-size: 12px;">content of nitrogen DBP (HAN and CP) was found in the hydrophilic NOM fraction.&nbsp;</span><span style="font-size: 12px;">By examination of the combined processes of ozonation, TiO2-O3 and coagulation, it was&nbsp;</span><span style="font-size: 12px;">shown that oxidative treatments have a positive effect on NOM removal by coagulation. A&nbsp;</span><span style="font-size: 12px;">maximum efficacy in reducing DOC by 32% was achieved with 3.0 mg O3/mg DOC and&nbsp;</span><span style="font-size: 12px;">200 mg FeCl3/L, whereas slightly lower ozone doses are suitable for the removal of DBP&nbsp;</span><span style="font-size: 12px;">precursors (80-89% THMFP, HAAFP, HANFP and HKFP, using 0.7-1.0 mg O3/mg DOC&nbsp;</span><span style="font-size: 12px;">and 200 mg FeCl3/L). CP precursors which are formed during ozonation remain in the water&nbsp;</span><span style="font-size: 12px;">after coagulation.&nbsp;</span><span style="font-size: 12px;">The results obtained during this investigation show that the application of different oxidation&nbsp;</span><span style="font-size: 12px;">and enhanced oxidation processes can reduce the contents of NOM and DBP precursors to&nbsp;</span><span style="font-size: 12px;">some degree. The most effective process at removing both total organic matter and specific&nbsp;</span><span style="font-size: 12px;">DBP precursors proved to be the Fenton process. With respect to enhanced oxidation&nbsp;</span><span style="font-size: 12px;">processes based upon the use of ozone, by introducing catalysts or H2O2 as an oxidant in the&nbsp;</span><span style="font-size: 12px;">ozonation process and by selecting the optimum pH for the process, the oxidizability of&nbsp;</span><span style="font-size: 12px;">organic molecules can be improved. In addition, knowledge of the NOM oxidation&nbsp;</span><span style="font-size: 12px;">mechanisms from different sources using ozone and / or hydroxyl radicals, as well as the&nbsp;</span><span style="font-size: 12px;">mechanism of NOM removal by coagulation, can be used to select and optimize the most&nbsp;</span><span style="font-size: 12px;">appropriate process in drinking water treatment, depending upon the quality of the raw water.</span></p>

<p>Cilj ovog rada je bio da se ispita uticaj ozona i ozon/vodonik-peroksida na efikasnost uklanjanja POM i prekursora oksidacionih nusproizvoda, procesima koagulacije, flokulacije i adsorpcije. Posebna pažnja posvećena je ispitivanju uticaja navedenih procesa na sadržaj prekursora oksidacionih nusproizvoda hlora (trihalometana i halosirćetnih kiselina), kao i na uticaj hipohlorita na formiranje ovih jedinjenja u tretiranoj vodi. Analiza hemijskih karakteristika sirove podzemne vode kori&scaron;ćene u ispitivanjima pokazuje da sadrži visok nivo POM pretežno hidrofobnog karaktera (PB = 37,7&plusmn;0,60 mg KMnO4/l; DOC = 9,27&plusmn;0,92 mg C/l; UV254 = 0,497&plusmn; 0,015 cm-1; SUVA = 5,36&plusmn;0,49 1 mg-1 m-1; PFTHM = 555&plusmn;128 &micro;g/l; PFHAA = 245&plusmn;54,9 &micro;g/l), kao i visoku koncentraciju arsena (51,7&plusmn;16,4 &micro;g/l).<br />Poređenjem uticaja dve ispitivane vrste koagulanata (FeCl3 i FeCl3/PACl) utvrđeno je da imaju različite mehanizme uklanjanja POM i prekursora oksidacionih nusproizvoda. FeCl3/PACl omogućava smanjenje sadržaja POM izraženih preko vrednosti DOC, PB, UV254 apsorbancije i SUVA za 54%, 71%, 88% i 74%, u odnosu na sirovu vodu respektivno, dok se koagulacijom sa FeCl3 postiže smanjenje DOC, PB, UV254 apsorbancije i SUVA za 51%, 48%, 61% i 21%, respektivno. U vodi nakon koagulacije sa FeCl3 zaostaju POM hidrofobnog karaktera (SUVA = 5,12 l m-1 mg-1), dok se POM u koagulisanoj vodi sa FeCl3/PACl, mogu okarakterisati kao hidrofilne (SUVA = 1,70 l m-1 mg-1). Koagulacija sa FeCl3 i FeCl3/PACl omogućila je smanjenje sadržaja arsena u vodi za preko 95%, pri čemu su koncentracije As u koagulisanoj vodi bile niže od 10 &micro;g/l. Ozon i O3/H2O2 proces pokazuju sličnu efikasnost u smanjenju sadržaja POM i prekursora oksidacionih nusproizvoda. Poređenjem kombinovanih tretmana koji obuhvataju oksidacioni predtretman i koagulaciju, utvrđeno je da efikasnost koagulacije sa FeCl3 i FeCl3/PACl u smanjenju vrednosti DOC, PB, UV254, SUVA, PFTHM i aldehida, uglavnom zavisi od mehanizma delovanja samih koagulanata, dok ozon i O3/H2O2 proces doprinose smanjenju vrednosti ovih parametara kroz oksidaciju i izdvajanje lako isparljivih komponenti iz vode stripingom gasa. Sa aspekta promene sadržaja prekursora HAA, ozon i O3/H2O2 proces omogućavaju povećanje efikasnosti procesa koagulacije sa FeCl3 i FeCl3/PACl, u odnosu na koagulaciju bez oksidacionog predtretmana.<br />Kada se uzmu u obzir vrednosti svih navedenih parametara, kao i primenjenje doze oksidacionih sredstava i koagulanata, najbolji rezultati u uklanjanju POM i prekursora oksidacionih nusproizvoda (smanjenje vrednosti DOC za 55%, UV254 i SUVA za vi&scaron;e od 90%, u odnosu na sirovu vodu; PB = 7,70 mg KMnO4/l;&nbsp; PFTHM =158-188 &micro;g/l; PFHAA = 33,0-53,8 &micro;g/l i sadržaj aldehida 16,7-17,9 &micro;g/l) postižu se primenom tretmana koji obuhvataju oksidacioni predtretman ozonom (3,0 g O3/m3), odnosno O3/H2O2&nbsp; (3,3 g O3/m3; H2O2:O3 =1:1), koagulaciju (30 g FeCl3/m3 / 30 g Al/m3) uz recirkulaciju flokulacionog mulja i adsorpciju na zeolitu, flokulaciju, sedimentaciju i filtraciju na pe&scaron;čano/antracitnom filtru.<br />Za zavr&scaron;nu obradu vode GAU filtracijom pre procesa dezinfekcije, na osnovu svih ispitivanih parametara, kao najefikasniji u uklanjanju POM i prekursora oksidacionih nusproizvoda (THM, HAA i aldehida) pokazao se GAU Norit Row 0,8 Supra.<br />Hlorisanjem u simuliranim uslovima dezinfekcije, utvrđeno je da voda dobijena nakon GAU filtracije u ispitivanim tretmanima, ima zadovoljavajući kvalitet sa aspekta sadržaja THM i HAA (sadržaj THM je 69,7-77,4 &micro;g/l; koncentracija DCAA je &lt; MDL) čije su maksimalno dozvoljene koncentracije regulisane u vodi za piće (100 &micro;g/l za THM i 50 &micro;g/l za DCAA).<br />Statističkom obradom podataka iz laboratorijskih i pilot ispitivanja utvrđene su empirijske zavisnosti koje se mogu primenjivati za predviđanje koncentracije THM i HAA u tretiranoj vodi nakon tretmana ispitivanih na pilot postrojenju. Da bi se mogle primeniti za druge vrste vode i drugačije dizajnirane tetmane, neophodno je izvr&scaron;iti validaciju primenom nezavisnog seta podataka.&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<br />Svi rezultati dobijeni u toku istraživanja ukazuju na neophodnost primene oksidacionih sredstava u tretmanu ispitivane podzemne vode. Zbog različitog mehanizma delovanja, neophodno je izvr&scaron;iti odabir odgovarajuće vrste i doze oksidacionog sredstva, kao i koagulanta u tretmanu vode za piće, uzimajući u obzir karakteristika sirove vode i efikasnost koja se želi postići. Primena optimalnih doza ozona i O3/H2O2 omogućava povećanje efikasnosti uklanjanja POM i prekursora oksidacionih nusporizvoda, procesima koagulacije, flokulacije i adsorpcije. Odabirom odgovarajućih uslova tretmana postiže se da i nakon hlorisanja u postupku dezinfekcije, voda zadovoljava kriterijume kvaliteta vode za piće, sa aspekta sadržaja trihalometana i halosirćetnih kiselina.</p> / <p>The aim of this work was to investigate influence of ozone and ozone/hydrogen peroxide on efficiency of coagulation, flocculation and adsorption on natural organic matter and oxidation by-products removal. Special attention was dedicated to investigation of these processes on chlorine oxidation by-products (trihalomethanes and haloacetic acids) as well as on hypochlorite influence on formation of these compounds in treated water. The analysis of chemical characteristics of raw ground water used in this investigation show that it contains high amount of NOM, mainly of hydrophobic nature (PB = 37,7&plusmn;0,60 mg KMnO4/l; DOC = 9,27&plusmn;0,92 mg C/l; UV254 = 0,497&plusmn; 0,015 cm-1; SUVA = 5,36&plusmn;0,49 1 mg-1 m-1; PFTHM = 555&plusmn;128 &mu;g/l; PFHAA = 245&plusmn;54,9 &mu;g/l) as well as high arsenic concentration (51,7&plusmn;16,4 &mu;g/l).<br />Comparing the influences of two investigated coagulants (FeCl3 and FeCl3/PACl) it was observed that they have different mechanisms of NOM and oxidation by-products precursors&rsquo; removal. FeCl3/PACl enables reduction of DOC, PB, UV254 absorbance and SUVA value for 54%, 71%, 88% i 74%, respectively, relative to raw water. Coagulation with FeCl3 provides reduction of DOC, PB, UV254 absorbance and SUVA for 51%, 48%, 61% i 21%, respectively. In water coagulated with FeCl3 remains NOM of hydrophobic nature (SUVA = 5,12 l m-1 mg-1) while NOM in coagulated water with FeCl3/PACl can be characterized as hydrophilic (SUVA = 1,70 l m-1 mg-1). Coagulation with FeCl3 and FeCl3/PACl enables arsenic content reduction for over 95% relative to raw water, with As concentrations in coagulated water below of 10 &mu;g/l. Ozone and O3/H2O2 process demonstrates similar efficiency in NOM and oxidation by-products precursors content reduction. Comparing combined treatment which includes oxidation pretreatment and&nbsp;<span style="font-size: 12px;">coagulation, it was observed that efficiency of coagulation in DOC, PB, UV254, SUVA, PFTHM and aldehydes reduction mainly depends on coagulants activity mechanisms, while ozone and O3/H2O2 process contributes to reduction of these parameters through oxidation and removal of volatile compounds from water by gas stripping. Ozone and O3/H2O2 process enables increase of coagulation efficiency for HAA precursor&rsquo;s removal, comparing to coagulation without oxidation pretreatment.</span></p><p>Taking into account all measured parameters as well as applied doses of oxidation reagents and coagulants, it can be concluded that the best results in NOM and oxidation by-products precursors content reduction (decrease of DOC for 55%, UV254 i SUVA for more then 90%, related to raw water; PB = 7,70 mg KMnO4/l; PFTHM =158-188 &mu;g/l; PFHAA = 33,0-53,8 &mu;g/l and content of aldehydes 16,7-17,9 &mu;g/l) can be obtained by treatments which include oxidation pretreatment with ozone (3,0 g O3/m3), as well as with O3/H2O2 (3,3 g O3/m3; H2O2:O3 =1:1), coagulation (30 g FeCl3/m3 / 30 g Al/m3), with flocculation sludge recirculation and zeolit adsorption, flocculation, sedimentation and filtration on sand/anthracite filter.<br />For the final water treatment with GAC filtration before disinfection process, based on all parameters, GAC Norit Row 0,8 Supra was the most efficient in NOM and oxidation by-products precursors reduction (THM, HAA and aldehydes).<br />After chlorination in simulated disinfection conditions, it was determined that water after GAC filtration in investigated treatments has satisfactory quality in terms of regulated THM and HAA (content of THM is 69,7-77,4 &mu;g/l; concentration of DCAA is &lt; MDL) which maximal allowable level for drinking water is established (100 &mu;g/l for THM and 50 &mu;g/l for DCAA).<br />By statistical analysis of data obtained in laboratory and pilot scale experiments it was determined empirical relations for THM and HAA concentration predictions in treated water.<br />All obtained results in this research indicate that oxidation reagents need to be applied in treatment of investigated ground water. Because of different action mechanism, it is necessary to select the adequate type and dose of oxidation reagent and coagulant in water treatment, taking into account characteristics of raw water and efficiency that needs to be achieved. Application of optimal doses of ozone and O3/H2O2 enables increase of coagulation, flocculation and adsorption efficiency in NOM and oxidation by-products precursors&rsquo; removal. Selection of adequate treatment conditions provides that after chlorination in disinfection process water satisfies drinking water quality criteria, in terms of trihalomethanes and haloacetic acids.</p>

[ES] El agua es esencial para la vida. La presente Tesis ha estudiado el uso de ozono y peroximonosulfato como oxidantes en tratamientos de agua para el control de subproductos de desinfección o degradación de contaminantes. La pre-ozonización del agua natural, se consideró como un tratamiento general del agua potable capaz de minimizar la formación de subproductos de la desinfección (DBP). En esta tesis, sin embargo, se ha demostrado que la pre-ozonización de aguas superficiales que contienen cianobacterias comunes, no es un tratamiento adecuado para controlar los DBP basados en cloración (trihalometanos, ácidos haloacéticos, halonitrilos, halocetonas y tricloronitrometano). Los procesos de oxidación avanzada (POAs) basados en ozono y peroximonosulfato se consideran algunas de las tecnologías preferibles para la degradación de contaminantes del agua. Esta tesis ha demostrado que la funcionalización adecuada del carbón activo mediante tratamiento químico da como resultado una funcionalización superficial del carbón con una gran población de grupos funcionales de oxígeno capaces de depositar pequeñas nanopartículas de cobalto. El material resultante exhibe una actividad catalítica para la activación del PMS y la degradación del fenol superior a la mayoría de los estudios previos en este campo. También ha mostrado la posibilidad de desarrollar catalizadores de ozonización libres de metales altamente activos basados en grafito de alta área superficial hidroxilado en los bordes o en nanodiamantes sp2 / sp3 defectuosos. / [CA] L'aigua és essencial per a la vida. La present Tesi ha estudiat l'ús d'ozó i peroximonosulfat com oxidants en tractaments d'aigua per al control de subproductes de desinfecció o degradació de contaminants. La pre-ozonació de l'aigua natural, es va considerar com un tractament general de l'aigua potable capaç de minimitzar la formació de subproductes de la desinfecció (DBP). En aquesta tesi, però, s'ha demostrat que la pre-ozonació d'aigües superficials que contenen cianobacteries comuns, no és un tractament adequat per controlar els DBP basats en cloració (trihalometans, àcids haloacétics, halonitrilos, halocetones i tricloronitrometà). Els processos d'oxidació avançada (POAs) basats en ozó i peroximonosulfat es consideren algunes de les tecnologies preferibles per a la degradació de contaminants de l'aigua. Aquesta tesi ha demostrat que la funcionalització adequada del carbó actiu mitjançant tractament químic dóna com a resultat una funcionalització superficial de l'carbó amb una gran població de grups fun-cionals d'oxigen capaços de dipositar petites nanopartícules de cobalt. El material resultant exhibeix una activitat catalítica per a l'activació del PMS i la degradació del fenol superior a la majoria dels estudis previs en aquest camp. També ha mostrat la possibilitat de desenvolupar catalitzadors d'ozonització lliures de metalls altament actius basats en grafit d'alta àrea superficial hidroxilat en les vores o en nanodiamants sp2 / sp3 defectuosos. / [EN] Water is essential for life. The present Thesis studied the use of ozone and peroxymonosulfate as oxidants in water treatments for disinfection by-products control or pollutant degradation. Pre-ozonation of natural water was considered as a general drinking water treatment able to minimize the formation of DBPs. In this Thesis, however, it has been demonstrated that pre-ozonation of surface water containing common cyanobacteria is not a suitable treatment for controlling chlorination-based DBPs (trihalomethanes, haloacetic acids, haloace-tonitriles, haloketones and trichloronitromethane). AOPs based on ozone and peroxymonosulfate are considered to be some of the preferable technologies for water pollutant degradation. This Thesis has shown that appropriate activated carbon functionalization by chemical treatment results in a surface functionalization with a large population of oxygen functional groups able to deposit small cobalt nanoparticles. The resulting material exhibits a catalytic activity for PMS activation and phenol degradation superior to most of the previous studies in the field. It has also shown the possibility of developing highly active metal-free ozonation catalysts based on edged-hydroxylated high surface area graphite or defective sp2/sp3 nanodiamonds. / Bernat Quesada, F. (2021). Ozone and peroxymonosulfate as oxidants in water treatments for disinfection by-products control or pollutant degradation [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/174887 / TESIS

Tesis por compendio / [ES] La presente tesis doctoral abarcó el desarrollo de un ingrediente a partir del subproducto de la industria citrícola. Se buscó obtener un ingrediente en polvo, con alto contenido de fibra soluble, que pudiera utilizarse en la formulación de productos. El trabajo se dividió en cuatro etapas. Tras la obtención del ingrediente por diferentes metodologías, en las primeras etapas se analizó su composición química y propiedades tecno funcionales. Posteriormente se realizó un ensayo de estabilidad del ingrediente tras su almacenamiento a diferentes actividades de agua. Finalmente, se evaluó la incorporación del ingrediente, como fuente de fibra, en la formulación de un flan; se estudió el efecto de la información sobre el origen de la fibra agregada en la respuesta del consumidor y el efecto de la incorporación de dicha fibra sobre las propiedades sensoriales del producto. Se ensayaron cuatro tecnologías no contaminantes para la extracción de fibra soluble: agua caliente, extrusión + agua caliente, jet cooker y jet cooker + agua caliente. El sobrenadante de la extracción se secó en "spray dryer" obteniendo un ingrediente en polvo. El contenido de fibra alimentaria de alto y bajo peso molecular fue analizado, junto con el contenido de azúcares simples y de compuestos bioactivos. El contenido de fibra total varió entre 10 y 20 gramos por 100 gramos de producto entre los tratamientos ensayados, siendo el proceso de extrusión + agua caliente el que mayor contenido de fibra presentó. Además, este tratamiento fue el que presentó menor contenido de azúcares y mayor contenido de compuestos bioactivos. En la segunda etapa se analizaron la capacidad espumante y estabilidad de la espuma, retención de aceite, solubilidad en agua, higroscopicidad, microestructura, temperatura de transición vítrea, color y reología de las soluciones. Se observaron diferentes grados de aglomeración en los polvos, que se relacionaron con la baja temperatura de transición vítrea de los ingredientes, fruto de sus componentes de bajo peso molecular. Aunque todas las soluciones formaron espumas, la del ingrediente obtenido por extrusión + agua caliente fue la más estable, lo que pudo deberse a su mayor viscosidad. En la tercera etapa se almacenaron los ingredientes obtenidos a diferentes actividades de agua durante 15 semanas, y una vez transcurrido el tiempo se modeló su isoterma de sorción. Además, se estudió la transición vítrea, junto con el contenido de compuestos bioactivos, color y textura. Los polvos no fueron estables en su estado inicial, debido al alto contenido de humedad que presentaban. Se observó pardeamiento a medida que aumenta la actividad de agua En la última etapa se evaluó la incorporación del ingrediente en la formulación de un flan. Se estudió el efecto de la información en la respuesta del consumidor y el efecto de su incorporación en las propiedades sensoriales. Se realizó una encuesta en España y Uruguay tomando como variables de estudio la intención de compra, y las percepciones de saludable y amigable con el medio ambiente. Se evaluaron tres categorías de producto diferentes (un producto listo para consumo, un polvo para preparar el postre en casa y un flan casero), variando la información ofrecida (origen de la fibra y un logo haciendo referencia a la sostenibilidad). El comportamiento de ambas poblaciones fue diferente en las tres variables de estudio, Para evaluar la incorporación del ingrediente en la formulación de un flan "fuente de fibra" (3% de contenido de fibra), se ensayaron diferentes porcentajes de sustitución de inulina (muestra control) del postre por el ingrediente de naranja obtenido a partir de la extrusión + agua caliente. La sustitución de un 30% del contenido total de fibra por el nuevo ingrediente logró un producto similar al control, sin descriptores de sabor no agradables y con una mejora en el brillo y la textura. / [CA] La investigació de la present tesi doctoral va abastar el desenvolupament d'un ingredient a partir del subproducte de la indústria citrícola. Es va buscar obtindre un ingredient en pols, amb alt contingut de fibra soluble, que poguera utilitzar-se en la formulació d'altres productes. Per a això el treball es va dividir en quatre etapes. Després de l'obtenció de l'ingredient per les diferents metodologies, en les primeres etapes es van analitzar la seua composició química i propietats tecno funcionals. Posteriorment es va feir un assaig d'estabilitat de l'ingredient després del seu emmagatzematge a diferents activitats d'aigua. Finalment, es va avaluar la incorporació de l'ingredient, com a font de fibra, en la formulació d'un flam; es va presentar l'efecte de la informació sobre l'origen de la fibra agregada en la resposta del consumidor i l'efecte de la incorporació d'aquesta fibra sobre les propietats sensorials del producte. Es van assajar quatre tecnologies no contaminants per a l'extracció de fibra soluble: aigua calenta, extrusió+aigua calenta, jet cooker i jet cooker+aigua calenta. El sobrenedant de l'extracció es va assecar en "spray dryer" obtenint un ingredient en pols. El contingut de fibra alimentària d'alt i baix pes molecular va ser analitzat juntament amb el contingut de sucres simples i de compostos bioactius. El contingut de fibra total va variar entre 10 i 20 grams per 100 grams de producte entre els tractaments assajats, sent el procés d'extrusió+aigua calenta el que major contingut de fibra va presentar. A més, aquest tractament va ser el que va presentar menor contingut de sucres i major contingut de compostos bioactius. En la segona etapa es van analitzar la capacitat espumant i estabilitat de l'espuma, retenció d'oli, solubilitat en aigua, higroscopicitat, microestructura, temperatura de transició vítria, color i reologia de les solucions. Es van observar diferents graus d'aglomeració en les pólvores, que es van relacionar amb la baixa temperatura de transició vítria dels ingredients, fruit dels seus components de baix pes molecular. Tot i que totes les solucions van a formar espumes, la de l'ingredient obtingut per extrusió+aigua calenta va ser la més estable, la qual cosa va poder deure's a la seua major viscositat. En la tercera etapa es van emmagatzemar els ingredients obtinguts a diferents activitats d'aigua durant 15 setmanes, i una vegada transcorregut el temps es va modelar la seua isoterma de sorció. A més, es va estudiar la transició vítria, juntament amb el contingut de compostos bioactius, color i textura. Les pólvores no van ser estables en el seu estat inicial, a causa de l'alt contingut d'humitat que presentaven. Es va observar pardejament a mesura que augmenta l'activitat d'aigua. En l'última etapa es va avaluar la incorporació de l'ingredient en la formulació d'un flam. Es va estudiar l'efecte d'informació sobre l'ingredient en la resposta del consumidor i l'efecte de la seua incorporació en les propietats sensorials. Es va fer una enquesta a Espanya i l'Uruguai prenent com a variables d'estudi la intenció de compra, i la percepció de saludable i amigable amb el medi ambient. Es van avaluar tres categories de producte diferents (un producte llest per a consum, una pols per a preparar les postres a casa i un flam casolà), variant la informació oferida (origen de la fibra i un logo fent referència a la sostenibilitat). El comportament de totes dues poblacions va ser diferent en les tres variables d'estudi. Per a avaluar la incorporació de l'ingredient en la formulació d'un flam "font de fibra" (3% de contingut de fibra), es van assajar diferents percentatges de substitució d'inulina (mostra control) de les postres per l'ingredient de taronja obtingut a partir de l'extrusió + aigua calenta. La substitució d'un 30% del contingut total de fibra pel nou ingredient va aconseguir un producte similar al control, sense descriptors de sabor no agradables, amb una millora en la lluentor i la textura / [EN] This thesis covered the development of an ingredient from the by-product of the citrus industry. The aim was to obtain a powdered ingredient, with high soluble fiber content, that could be used in the formulation of other products. The work was divided into four stages. After obtaining the ingredient by the different methodologies, in the first stages its chemical composition and techno-functional properties were analyzed. Afterwards, a stability test of the ingredient was carried out after storage at different water activities. Finally, theincorporation of the ingredient as a source of fiber, in the formulation of a flan was evaluated; the effect of information on the origin of the added fiber on consumer response and the effect of incorporating said fiber on the sensory properties of the product were studied. Four non-contaminant technologies for the extraction of soluble fiber were tested. These were hot water, extrusion + hot water, jet cooker, and jet cooker + hot water. The extraction supernatant was dried in a spray dryer to obtain a powdered ingredient. The content of high and low molecular weight dietary fiber and the content of simple sugars and bioactive compounds were analyzed. The total fiber content varied between 10 and 20 grams per 100 grams of product among the tested treatments, being the extrusion + hot water process the one with the highest fiber content. In addition, this treatment was the one with the lowest sugar content and the highest content of bioactive compounds. In the second stage, the foaming capacity and stability, oil holding capacity, water solubility, hygroscopicity, microstructure, glass transition temperature, color and rheology of the solutions were analyzed. Different degrees of caking were observed in the powders, which were related to the low glass transition temperature of the ingredients, due to their low molecular weight components. Although all the solutions formed foams, the foam of the ingredient obtained by extrusion + hot water was the most stable, which could be due to its higher viscosity. In the third stage, the ingredients obtained were stored at different water activities for 15 weeks, and once the time had elapsed, their sorption isotherm was modeled. In addition, the glass transition was studied, along with the content of bioactive compounds, color, and texture. The powders were not stable in their initial state, due to their high moisture content. Browning was observed as the water activity increased. In the last stage, the incorporation of the ingredient in the formulation of a flan was evaluated. The effect of information about the ingredient on consumer response and the effect of its incorporation on the sensory properties of the dessert were studied. To evaluate the effect of information on consumer response, a survey was carried out in Spain and Uruguay, taking purchase intention and healthiness and environmental friendliness perceptions as study variables. Three different product categories were evaluated (a ready-to-eat product, a powder to prepare dessert at home and a homemade flan), varying the information offered (origin of the fiber and a logo referring to sustainability). The behavior of both populations was different in the three study variables. To evaluate the incorporation of the ingredient in the formulation of a "fiber source" (total fibre content 3%) flan, different percentages of substitution of inulin content (control sample) the total fiber content of the dessert by the orange ingredient obtained from extrusion + hot water were tested. The substitution of 30% of the total fiber content with the new ingredient achieved a product similar to the control, without unpleasant flavor descriptors and with an improvement in brightness and texture. / This work was supported by the National Innovation and Investigation Agency (ANII), Uruguay, under code POS_EXT_2018_1_154449. / Pérez Pirotto, C. (2022). Obtención de fibra alimentaria a partir del subproducto de la industria citrícola, a través de la aplicación de diferentes tecnologías de extracción [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/191431 / Compendio

Coffee leaf tea is prepared as an infusion of dried leaves of Coffea spp. in hot water. It is a traditional beverage in some coffee-producing countries and has been authorized in 2020 within the European Union (EU) according to its novel food regulation. This article reviews current knowledge on the safety of coffee leaf tea. From the various ingredients contained in coffee leaves, only two were highlighted as possibly hazardous to human health, namely, caffeine and epigallocatechin gallate (EGCG), with maximum limits implemented in EU legislation, which is why this article focuses on these two substances. While the caffeine content is comparable to that of roasted coffee beans and subject to strong fluctuations in relation to the age of the leaves, climate, coffee species, and variety, a maximum of 1–3 cups per day may be recommended. The EGCG content is typically absent or below the intake of 800 mg/day classified as hepatotoxic by the European Food Safety Authority (EFSA), so this compound is suggested as toxicologically uncritical. Depending on selection and processing (age of the leaves, drying, fermentation, roasting, etc.), coffee leaf tea may exhibit a wide variety of flavors, and its full potential is currently almost unexplored. As a coffee by-product, it is certainly interesting to increase the income of coffee farmers. Our review has shown that coffee leaf tea is not assumed to exhibit risks for the consumer, apart from the well-known risk of caffeine inherent to all coffee-related beverages. This conclusion is corroborated by the history of its safe use in several countries around the world.