37 results on '"Ponsá S"'
Search Results
2. Nitrogen fertilization with pig slurry in a barley-sorghum double-annual forage cropping system
- Author
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Ovejero, J., Maresma, A., Marks, E. A. N., Ortiz, C., Boixadera, J., Serra, X., Ponsá, S., Lloveras, J., and Casas, C.
- Published
- 2022
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3. Biomass fuel production from cellulosic sludge through biodrying: Aeration strategies, quality of end-products, gaseous emissions and techno-economic assessment
- Author
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Guerra-Gorostegi, N., González, D., Puyuelo, B., Ovejero, J., Colón, J., Gabriel, D., Sánchez, A., and Ponsá, S.
- Published
- 2021
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4. Multilevel environmental assessment of the anaerobic treatment of dairy processing effluents in the context of circular economy
- Author
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Stanchev, P., Vasilaki, V., Egas, D., Colon, J., Ponsá, S., and Katsou, E.
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- 2020
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5. CalcPEFDairy: A Product Environmental Footprint compliant tool for a tailored assessment of raw milk and dairy products
- Author
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Egas, D., Ponsá, S., and Colon, J.
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- 2020
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6. Implementation of the Product Environmental Footprint Category Rules for dairy products: An approach to assess nitrogen emissions in a mass balanced dairy farm system
- Author
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Egas, D., Vasilaki, V., Katsou, E., Stanchev, P., Ponsá, S., and Colon, J.
- Published
- 2019
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7. Municipal solid waste management and waste-to-energy in the context of a circular economy and energy recycling in Europe
- Author
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Malinauskaite, J., Jouhara, H., Czajczyńska, D., Stanchev, P., Katsou, E., Rostkowski, P., Thorne, R.J., Colón, J., Ponsá, S., Al-Mansour, F., Anguilano, L., Krzyżyńska, R., López, I.C., A.Vlasopoulos, and Spencer, N.
- Published
- 2017
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8. Analysis of MSW full-scale facilities based on anaerobic digestion and/or composting using respiration indices as performance indicators
- Author
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Colón, J., Ponsá, S., Álvarez, C., Vinot, M., Lafuente, F.J., Gabriel, D., and Sánchez, A.
- Published
- 2017
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9. Saving freshwater from salts
- Author
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Cañedo-Argüelles, M., Hawkins, C. P., Kefford, B. J., Schäfer, R. B., Dyack, B. J., Brucet, S., Buchwalter, D., Dunlop, J., Frör, O., Lazorchak, J., Coring, E., Fernandez, H. R., Goodfellow, W., Achem, A. L. González, Hatfield-Dodds, S., Karimov, B. K., Mensah, P., Olson, J. R., Piscart, C., Prat, N., Ponsá, S., Schulz, C.-J., and Timpano, A. J.
- Published
- 2016
10. WATER: Saving freshwater from salts
- Author
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Cañedo-Argüelles, M., Hawkins, C. P., Kefford, B. J., Schäfer, R. B., Dyack, B. J., Brucet, S., Buchwalter, D., Dunlop, J., Frör, O., Lazorchak, J., Coring, E., Fernandez, H. R., Goodfellow, W., González Achem, A. L., Hatfield-Dodds, S., Karimov, B. K., Mensah, P., Olson, J. R., Piscart, C., Prat, N., Ponsá, S., Schulz, C.-J., and Timpano, A. J.
- Published
- 2016
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11. Evaluating the impacts of treated and untreated hypersaline effluents from abandoned mines on freshwater ecosystems
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Vendrell, L., Abril, M., Proia, L., Espinosa, Carmen, Morin, Soizic, Colón, J., Ponsá, S., Llenas, L., Irstea Publications, Migration, UNIVERSITY OF VIC BETA TECHNOLOGICAL CENTER VIC ESP, Partenaires IRSTEA, Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Ecosystèmes aquatiques et changements globaux (UR EABX), and Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)
- Subjects
[SDE] Environmental Sciences ,[SDE]Environmental Sciences ,INHIBITION DE LA PHOTOSYNTHÈSE ,SELS ,EFFLUENTS MINIERS - Abstract
International audience; Abandoned mines cause serious environmental damage to surroundings, with considerable impacts on freshwater ecosystems. Impacts occur through uncontrolled discharge of polluted effluents containing contaminants with high salts concentrations. Currently, no real solution exists for this environmental problem, being a global pollution problem. This study evaluates the efficiency of an innovative treatment, proposed on Life DEMINE project, based on membrane processes, electrocoagulation and the combination of both, to decrease environmental impacts caused by mining effluents from abandoned mines on freshwater ecosystems, using aquatic biofilms as indicator of ecological impacts. We incubated natural biofilms from a reference stream in different microcosms under controlled temperature and light conditions. After two weeks of colonization, on cleaned and previously autoclaved cobbles, biofilms were exposed to treated and untreated effluents from Menteroda salt mine (Germany), mimicking the real dilution occurring when discharge into the aquatic ecosystems. Biofilms responses were measured at 1, 7 and 15 days after the exposure began. We observed a significant reduction of biofilm photosynthetic efficiency after 24h of exposure in all treatments that recovered one week later. Chlorophyll-a concentrations, diatoms and cyanobacteria community of aquatic biofilm were affected by all treatments compared to the control from 24h until the end of the exposure. Phosphate uptake capacity decreased significantly after 24h of exposure in all treatments but recovered one week later. These observations evidenced ecological impact of hypersaline mining effluents on aquatic ecosystems and the potential of the innovative treatment proposed to improve the quality of water bodies affected by abandoned mines.
- Published
- 2019
12. Municipal Waste Management and Waste-to-Energy in the Context of a Circular Economy and Energy Recycling in Europe
- Author
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Malinauskaite, J, Jouhara, H, Czajczyńska, D, Stanchev, P, Katsou, E, Rostkowsk, P, Thorne, RJ, Colón, J, Ponsá, S, Al-Mansour, F, Anguilano, L, Krzyżyńska, R, López, IC, Vlasopoulos, A, and Spencer, N
- Subjects
waste to energy ,anaerobic digestion ,national waste management plans ,composting ,municipal solid waste ,pyrolysis - Abstract
This paper proposes an overarching review of national municipal waste management systems and waste-to-energy as an important part of it in the context of circular economy in the selected countries in Europe. The growth of population and rising standards of living means that the consumption of goods and energy is increasing. On the one hand, consumption leads to an increase in the generation of waste. On the other hand, the correlation between increased wealth and increased energy consumption is very strong as well. Given that the average heating value of municipal solid waste (MSW) is approximately 10 MJ/kg, it seems logical to use waste as a source of energy. Traditionally, waste-to-energy (WtE) has been associated with incineration. Yet, the term is much broader, embracing various waste treatment processes generating energy (for instance, in the form of electricity and/or heat or producing a waste-derived fuel). Turning waste into energy can be one key to a circular economy enabling the value of products, materials, and resources to be maintained on the market for as long as possible, minimising waste and resource use. As the circular economy is at the top of the EU agenda, all Member States of the EU (including the EEA countries) should move away from the old-fashioned disposal of waste to a more intelligent waste treatment encompassing the circular economy approach in their waste policies. Therefore, the article examines how these EU policies are implemented in practice. Given that WtE traditionally is attached to the MSW management and organisation, the focus of this article is twofold. Firstly, it aims to identify the different practices of municipal waste management employed in selected countries and their approaches in embracing the circular economy and, secondly, the extent to which WtE technologies play any role in this context. The following countries, Estonia, Greece, Italy, Latvia, Lithuania, Norway, Poland, Slovenia, Spain, and the UK were chosen to depict a broad European context.
- Published
- 2017
13. From Wastes to High Value Added Products: Novel Aspects of SSF in the Production of Enzymes.
- Author
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El-Bakry, M., Abraham, J., Cerda, A., Barrena, R., Ponsá, S., Gea, T., and Sánchez, A.
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SOLID-state fermentation ,ENZYMES ,CHEMICAL synthesis ,PROTEOLYTIC enzymes ,LIPASES ,AGRICULTURAL wastes ,FOOD industry - Abstract
Solid-state fermentation (SSF), a process that occurs in the absence or near absence of water, has been used for the production of various high value added products such as enzymes and other organic components. This paper reviews the recent studies reported on the use of SSF for the production of enzymes: lipases, proteases, cellulases, hemicellulases, ligninases, glucoamylases, pectinases, and inulinases. The microorganisms used for fermentation are mostly fungi, and substrates are waste materials from the agriculture and food industry. This shows the advantages of SSF from an economical and environmental viewpoint. The paper provides an update on several issues, viz. wastes, microorganisms, and issues of scaling up and controlling the process of fermentation in solid state. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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14. Characterization of odorous compounds and odor load in indoor air of modern complex MBT facilities.
- Author
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Colón, J., Alvarez, C., Vinot, M., Lafuente, F.J., Ponsá, S., Sánchez, A., and Gabriel, D.
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SOLID waste management , *ODORS , *HYDROGEN sulfide , *VOLATILE organic compounds , *INDOOR air pollution - Abstract
Gaseous emissions and chemical compounds responsible for odor nuisance are the most common social concerns arising from modern municipal mechanical-biological waste treatment (MBT) facilities. Regarding to this, an inventory of indoor concentrations of hydrogen sulfide and volatile organic compounds (VOCs) along with odor analyses were carried out at three different full-scale MBT facilities. 48-h profiles of total volatile organic compounds (tVOCs) and hydrogen sulfide were performed in selected areas (reception warehouse, pretreatment, anaerobic digestion and composting areas) and a complete gases and odor characterization were performed at two selected moments of the day according to maximum and minimum tVOCs concentrations, which corresponded to day/night variations. Terpenoids, aromatic hydrocarbons and aliphatic hydrocarbons were the families of VOCs more often detected. The average percentage of contribution of these three VOCs families was 32, 21 and 24%, respectively, while the average percentage of contribution of other VOCs families ranged from 0.2 to 5.5%. A multiple regression method was developed as a simple tool for odor modeling and prediction, showing that 98.5% (p < 0.001) of the variance in odor concentration could be explained by the concentrations of hydrogen sulfide and tVOCs. Results obtained suggested that optimization of indoor ventilation systems and, concomitantly, operational costs of MBT facilities was possible in certain locations where ventilation could be reduced up to 20–25% during night hours. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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15. Pig slurry fertilization in a double-annual cropping forage system under sub-humid Mediterranean conditions.
- Author
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Ovejero, J., Ortiz, C., Boixadera, J., Serra, X., Ponsá, S., Lloveras, J., and Casas, C.
- Subjects
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FORAGE , *NITRATE minerals , *LIVESTOCK development , *SOIL formation - Abstract
In areas of Southern Europe with very intensive pig production, most of the pig slurry (PS) is applied as fertilizer. However, in the European Union, no more than 170 kg N ha −1 year −1 can be applied in nitrate vulnerable zones (NVZs) from livestock manures. In this context, a six-year trial was conducted for a maize-triticale double-annual forage cropping rotation under rainfed conditions. Four different N rates were applied (0, 170, 250 and 330 kg N ha −1 year −1 ), to evaluate their effect on crop yield, N uptake, unrecovered N and soil nitrate content. The corresponding PS rates were defined as zero (PS 0), low (PSL) medium (PSM) and high (PSH). The annual average dry matter (DM) yields (maize + triticale) for the PS fertilization treatments PS0, PSL, PSM and PSH were 12.6, 17.7, 20.2 and 22.0 Mg DM ha −1 , respectively. Maize DM yield was influenced mainly by weather conditions, and triticale DM yield was clearly influenced by initial soil NO 3 − -N and PS fertilization rates. Unrecovered N was affected by PS fertilization rate and initial soil NO 3 − -N content. A residual effect of the PS when applied to maize had an important effect on soil NO 3 − -N and subsequent triticale DM yield. Moreover, total annual average unrecovered N, considering the sum of both crops (maize + triticale), were 91, 144, and 222 kg N ha −1 in PSL, PSM and PSH, respectively. In order to avoid part of this unrecovered N, mainly by lixiviation of nitrates, PS fertilization in triticale should be applied as side dressing at tillering. The application of N, in the form of PS, at rates higher than the legally permitted maximum of 170 kg N ha −1 year −1 , may result in better yields. However, high rates of PS fertilization may originate in significantly lower N use efficiency and a higher potential environmental impact in double-cropping systems, practiced in rainfed sub-humid Mediterranean conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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16. Novel biostimulant bacterial exopolysaccharides production via solid-state fermentation as a valorisation strategy for agri-food waste.
- Author
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Garcia-Muchart E, Martínez-Avila O, Mejias L, Gilles E, Bluteau C, Lavergne L, and Ponsá S
- Abstract
Bacterial exopolysaccharides (EPS) are extracellular polymer-based substances recently defined as potential plant biostimulants, as they can increase nutrient uptake, water retention, and resistance to abiotic stress. As sugar-based substances, the bacteria producing them need to grow in a sugar-rich substrate. Hence, some agri-food by-products could be used as suitable carbon sources for EPS production as a cost-effective and more sustainable alternative to conventional substrates. Thus, this study aimed to produce EPS from specific bacterial strains through solid-state fermentation (SSF) using agri-food waste as a low-cost substrate. Six residues and five bacterial strains were tested in a lab-scale SSF system. From the assessed substrate-strain combinations, Burkholderia cepacia with ginger juice waste (GJW) resulted in the most promising considering several process parameters (EPS production, cumulative oxygen consumption, biomass growth, reducing sugars consumption). Also, dynamic monitoring of the system allowed for establishing 5 days as a suitable fermentation time. Then, using response surface methodology (Box-Behnken design), the process was optimised based on airflow rate (AF), inoculum size (IS), and micronutrient concentration (MN). In this stage, the best conditions found were at 0.049 (± 0.014) L h
-1 per gram of dry matter (DM) for AF, 8.4 (± 0.9) E + 09 CFU g-1 DM for IS, and 0.07 (± 0.01) mL g-1 DM for MN, reaching up to 71.1 (± 3.2) mg crude EPS g-1 DM. Results show the potential of this approach to provide a new perspective on the value chain for the agri-food industry by introducing it to a circular economy framework., (© 2024. The Author(s).)- Published
- 2024
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17. Nature-based bioreactors: Tackling antibiotic resistance in urban wastewater treatment.
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Bertrans-Tubau L, Martínez-Campos S, Lopez-Doval J, Abril M, Ponsá S, Salvadó V, Hidalgo M, Pico-Tomàs A, Balcazar JL, and Proia L
- Abstract
The overuse and misuse of antibiotics have accelerated the selection of antibiotic-resistant bacteria, significantly impacting human, animal, and environmental health. As aquatic environments are vulnerable to antibiotic resistance, suitable management practices should be adopted to tackle this phenomenon. Here we show an effective, nature-based solution for reducing antibiotic resistance from actual wastewater. We utilize a bioreactor that relies on benthic (biofilms) and planktonic microbial communities to treat secondary effluent from a small urban wastewater treatment plant (<10,000 population equivalent). This treated effluent is eventually released into the local aquatic ecosystem. We observe high removal efficiency for genes that provide resistance to commonly used antibiotic families, as well as for mobile genetic elements that could potentially aid in their spread. Importantly, we notice a buildup of sulfonamide ( sul1 and sul2 ) and tetracycline ( tet(C) , tet(G) , and tetR ) resistance genes specifically in biofilms. This advancement marks the initial step in considering this bioreactor as a nature-based, cost-effective tertiary treatment option for small UWWTPs facing antibiotic resistance challenges., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors. Published by Elsevier B.V. on behalf of Chinese Society for Environmental Sciences, Harbin Institute of Technology, Chinese Research Academy of Environmental Sciences.)
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- 2024
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18. Dissipation of pesticides by stream biofilms is influenced by hydrological histories.
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Bertrans-Tubau L, Menard Y, Batisson I, Creusot N, Mazzella N, Millan-Navarro D, Moreira A, Morin S, Ponsá S, Abril M, Proia L, Romaní AM, and Artigas J
- Subjects
- Biofilms, Biological Transport, Biomass, Rivers, Pesticides pharmacology
- Abstract
To evaluate the effects of hydrological variability on pesticide dissipation capacity by stream biofilms, we conducted a microcosm study. We exposed biofilms to short and frequent droughts (daily frequency), long and less frequent droughts (weekly frequency) and permanently immersed controls, prior to test their capacities to dissipate a cocktail of pesticides composed of tebuconazole, terbuthylazine, imidacloprid, glyphosate and its metabolite aminomethylphosphonic acid. A range of structural and functional descriptors of biofilms (algal and bacterial biomass, extracellular polymeric matrix (EPS) concentration, microbial respiration, phosphorus uptake and community-level physiological profiles) were measured to assess drought effects. In addition, various parameters were measured to characterise the dynamics of pesticide dissipation by biofilms in the different hydrological treatments (% dissipation, peak asymmetry, bioconcentration factor, among others). Results showed higher pesticide dissipation rates in biofilms exposed to short and frequent droughts, despite of their lower biomass and EPS concentration, compared to biofilms in immersed controls or exposed to long and less frequent droughts. High accumulation of hydrophobic pesticides (tebuconazole and terbuthylazine) was measured in biofilms despite the short exposure time (few minutes) in our open-flow microcosm approach. This research demonstrated the stream biofilms capacity to adsorb hydrophobic pesticides even in stressed drought environments., (© The Author(s) 2023. Published by Oxford University Press on behalf of FEMS.)
- Published
- 2023
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19. A Novel Hybrid Membrane Process Coupled with Freeze Concentration for Phosphorus Recovery from Cheese Whey.
- Author
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Hidayat I, Paredes L, Binder PM, Guerra-Gorostegi N, Mora M, Ponsá S, Oatley-Radcliffe DL, and Llenas L
- Abstract
The ever-increasing demand for phosphorus fertilisers for securing global food production, coupled with finite phosphate rock reserves, is one of the emerging problems in the world. Indeed, phosphate rock is listed as an EU critical raw material, triggering attention to find an alternative source to substitute the use of this limited resource. Cheese whey, characterized by a high content of organic matter and phosphorus, represents a promising feedstock for phosphorus recovery and recycling. An innovative application of a membrane system coupled with freeze concentration was assessed to recover phosphorus from cheese whey. The performances of a microfiltration membrane (0.2 µm) and an ultrafiltration (200 kDa) membrane were evaluated and optimized under different transmembrane pressures and crossflow velocities. Once the optimal operating conditions were determined, a pre-treatment including lactic acid acidification and centrifugation was applied to increase the permeate recovery. Finally, the efficiency of progressive freeze concentration for the treatment of the permeate obtained from the optimum conditions (UF 200 kDa with TMP of 3 bar, CFV of 1 m/s and lactic acid acidification) was evaluated at specific operating conditions (-5 °C and 600 rpm of stirring speed). Finally, 70% of phosphorus could be recovered from cheese whey using the coupled technology of the membrane system and freeze concentration. A phosphorus-rich product was obtained with high agronomic value, which constitutes a further step towards establishing a broader circular economy framework.
- Published
- 2023
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20. Application of Vibrating Reverse Osmosis Technology for Nutrient Recovery from Pig Slurry in a Circular Economy Model.
- Author
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Vega E, Paredes L, Marks EAN, Singla B, Castaño-Sánchez O, Casas C, Vilaplana R, Mora M, Ponsá S, and Llenas L
- Abstract
The rapid growth of the livestock sector in some areas of Europe has caused an imbalance between the generation of livestock manure and the availability of agricultural soil for its direct application as a fertilizer. Since the transport of pig slurry to other areas with nutrient-deficient soils is costly from an economic point of view due to its high water content, the application of new technologies for the concentration of this waste is considered key for reducing management costs. Consequently, the main objective of this study was to demonstrate the potential of vibratory shear enhanced processing (VSEP) operated with reverse osmosis membranes to recover nutrients from the liquid fractions of pig slurry (LF-pig slurry) and digestate (LF-digestate) and obtain concentrated fertilizing products. Use of the VSEP unit permitted reductions in the water contents of the LF-pig slurry and LF-digestate, around 77% and 67%, respectively. Both VSEP concentrates were characterized by their significant nutrient contents and showed a nitrogen fertilizer replacement value similar to that of mineral fertilizer as demonstrated in a barley crop pot-test, although the salinity of the digestate concentrate was identified as a key limitation, negatively impacting the agronomic yield of the test crop.
- Published
- 2022
- Full Text
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21. Driving Factors of Geosmin Appearance in a Mediterranean River Basin: The Ter River Case.
- Author
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Espinosa C, Abril M, Bretxa È, Jutglar M, Ponsá S, Sellarès N, Vendrell-Puigmitjà L, Llenas L, Ordeix M, and Proia L
- Abstract
In recent decades, human activity coupled with climate change has led to a deterioration in the quality of surface freshwater. This has been related to an increase in the appearance of algal blooms, which can produce organic compounds that can be toxic or can affect the organoleptic characteristics of the water, such as its taste and odor. Among these latter compounds is geosmin, a metabolite produced by certain cyanobacteria that confers an earthy taste to water and which can be detected by humans at very low concentrations (nanogram per liter). The difficulty and cost of both monitoring the presence of this compound and its treatment is a problem for drinking water treatment companies, as the appearance of geosmin affects consumer confidence in the quality of the drinking water they supply. In this field study, the evaluation of four sampling sites with different physicochemical conditions located in the upper part of the Ter River basin, a Mediterranean river located in Catalonia (NE Spain), has been carried out, with the aim of identifying the main triggers of geosmin episodes. The results, obtained from 1 year of sampling, have made it possible to find out that: (i) land uses with a higher percentage of agricultural and industrial activity are related to high nutrient conditions in river water, (ii) these higher nutrient concentrations favor the development of benthic cyanobacteria, (iii) in late winter-early spring, when these cyanobacteria are subjected to both an imbalance of the dissolved inorganic nitrogen and soluble reactive phosphorus ratio, guided by a phosphorus concentration increase, and to cold-mild temperatures close to 10°C, they produce and release geosmin, and (iv) 1-2 weeks after cyanobacteria reach a high relative presence in the whole biofilm, an increase in geosmin concentration in water is observed, probably associated with the cyanobacteria detachment from cobbles and consequent cell lysis. These results could serve as a guide for drinking water treatment companies, indicating under what conditions they can expect the appearance of geosmin episodes and implement the appropriate treatment before it reaches consumers' tap., Competing Interests: The authors declare that this study received funding from Aigües de Vic S.A. and Aigües d’Osona S.A. The funder was not involved in the study design, collection, analysis, interpretation of data, the writting of this article, or the decision to submit it for publication. The handling editor SM declared a past co-authorship with several of the authors CE, MA, SP, LV-P, LL, LP., (Copyright © 2021 Espinosa, Abril, Bretxa, Jutglar, Ponsá, Sellarès, Vendrell-Puigmitjà, Llenas, Ordeix and Proia.)
- Published
- 2021
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22. Brewer's spent grain as a no-cost substrate for polyhydroxyalkanoates production: Assessment of pretreatment strategies and different bacterial strains.
- Author
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Corchado-Lopo C, Martínez-Avila O, Marti E, Llimós J, Busquets AM, Kucera D, Obruca S, Llenas L, and Ponsá S
- Subjects
- Edible Grain metabolism, Polyhydroxyalkanoates chemistry, Bacillus cereus metabolism, Burkholderia cepacia metabolism, Cupriavidus necator metabolism, Edible Grain chemistry, Polyhydroxyalkanoates biosynthesis
- Abstract
Polyhydroxyalkanoates (PHAs) are polyesters of significant interest due to their biodegradability and properties similar to petroleum-derived plastics, as well as the fact that they can be produced from renewable sources such as by-product streams. In this study, brewer's spent grain (BSG), the main by-product of the brewing industry, was subjected to a set of physicochemical pretreatments and their effect on the release of reducing sugars (RS) was evaluated. The RS obtained were used as a substrate for further PHA production in Burkholderia cepacia, Bacillus cereus, and Cupriavidus necator in liquid cultures. Although some pretreatments proved efficient in releasing RS (acid-thermal pretreatment up to 42.1 gRS L
-1 and 0.77 gRS g-1 dried BSG), the generation of inhibitors in such scenarios likely affected PHA production compared with the process run without pretreatment (direct enzymatic hydrolysis of BSG). Thus, the maximum PHA accumulation from BSG hydrolysates was found in the reference case with 0.31 ± 0.02 g PHA per g cell dried weight, corresponding to 1.13 ± 0.06 g L-1 and a PHA yield of 23 ± 1 mg g-1 BSG. It was also found that C. necator presented the highest PHA accumulation of the tested strains followed closely by B. cepacia, reaching their maxima at 48 h. Although BSG has been used as a source for other bioproducts, these results show the potential of this by-product as a no-cost raw material for producing PHAs in a waste valorization and circular economy scheme., (Copyright © 2021 Elsevier B.V. All rights reserved.)- Published
- 2021
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23. Effects of the interaction between nutrient concentration and DIN:SRP ratio on geosmin production by freshwater biofilms.
- Author
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Espinosa C, Abril M, Ponsá S, Ricart M, Vendrell-Puigmitjà L, Ordeix M, Llenas L, and Proia L
- Subjects
- Biofilms, Nutrients, Spain, Naphthols, Odorants analysis
- Abstract
The global increase of cyanobacterial blooms occurrence has been associated with the presence of compounds that generate earthy and musty odor in freshwater systems, among which geosmin stands out. The lack of information on the factors associated to geosmin production by benthic organisms has driven the development of this study, whose main goal is to determine the effects of nutrient concentration and DIN:SRP ratio on geosmin formation and release. The experiment was performed in 18 microcosms under controlled conditions for 21 days, using a natural biofilm suspension from Ter river (NE, Spain) to promote biofilm settlement. Six treatments were set crossing three DIN:SRP ratios (A = 4:1, B = 16:1 and C = 64:1) with two nutrient concentrations (Low and High). After 7 days of experiment, geosmin was detected in biofilm, being higher under high nutrient concentration and low DIN:SRP ratio conditions. In this treatment, geosmin in biofilm reached its maximum concentration at day 16 (3.8 ± 0.9 ng/mg), decreasing at the end of the experiment (21d) due to cyanobacteria detachment and geosmin release into the water (136 ± 6 ng/L). Overall, this experimental study showed that high nutrient concentration and low DIN:SRP ratio favored the Oscillatoria genus development within biofilm communities, generating the optimal conditions for geosmin production. The interaction between these two factors was demonstrated to be a potential driver of benthic geosmin production and release, and should be monitored and controlled in rivers exploited for drinking water purposes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier B.V. All rights reserved.)
- Published
- 2021
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24. Pharmaceuticals removal in an on-farm pig slurry treatment plant based on solid-liquid separation and nitrification-denitrification systems.
- Author
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Marti E, Gros M, Boy-Roura M, Ovejero J, Busquets AM, Colón J, Petrovic M, and Ponsá S
- Subjects
- Animals, Bioreactors, Farms, Nitrogen, Swine, Denitrification, Nitrification
- Abstract
The fate and degradation of 28 multiple-class veterinary pharmaceuticals in an on-farm pig slurry treatment plant based on solid-liquid separation and a nitrification-denitrification (NDN) sequence batch reactor (SBR) were evaluated for the first time. The pharmaceuticals detected at the highest concentrations in raw pig slurries belonged to the group of tetracycline antibiotics. Fluoroquinolone, lincosamide and pleuromutilin antibiotics and other drugs such as flubendazole and flunixin were also frequently detected. After solid-liquid separation, target compounds were distributed in an average of 64% onto the liquid fraction. Pharmaceuticals distributed in this fraction were removed in an average of almost 50% after being treated in NDN-SBR. Lincomycin was the compound with the highest removal percentage, reaching 100% reduction, while tetracyclines and fluoroquinolones showed moderate removal percentages (50 and 40%, respectively). Regarding nitrogen removal, NDN-SBR reduced a 77% of the content of this nutrient in the liquid slurry fraction., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Published
- 2020
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25. Techno-economic assessment of anaerobic co-digestion of livestock manure and cheese whey (Cow, Goat & Sheep) at small to medium dairy farms.
- Author
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Mostafa Imeni S, Pelaz L, Corchado-Lopo C, Maria Busquets A, Ponsá S, and Colón J
- Subjects
- Anaerobiosis, Animals, Biofuels economics, Cattle, Farms, Female, Goats, Livestock, Sheep, Cheese, Manure, Whey metabolism
- Abstract
Anaerobic digestion of manure is a common practice; however, the low biogas yield of manure can hamper the profitability of systems in small to medium farms. An increase in biogas yield could be achieved by co-digesting animal manure with co-substrates such as cheese whey. A Techno-economic assessment of anaerobic co-digestion of animal manure and cheese whey (cow, goat and sheep), has been carried out. The results obtained showed that for a farm with 250 adult cattle heads, the revenues generated in an anaerobic mono-digestion process are not able to offset the initial required investment. However, the co-digestion of manure with 30% of cheese whey showed a good economic performance and positive returns (Net Present values >0, Internal Rate of Return >11% and a Return of the investment in <10 years). Electricity selling price and biogas production are the key parameters to determine the profitability of the system., (Copyright © 2019 Elsevier Ltd. All rights reserved.)
- Published
- 2019
- Full Text
- View/download PDF
26. Filling in sewage sludge biodrying gaps: Greenhouse gases, volatile organic compounds and odour emissions.
- Author
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González D, Guerra N, Colón J, Gabriel D, Ponsá S, and Sánchez A
- Subjects
- Temperature, Greenhouse Gases chemistry, Odorants, Sewage, Volatile Organic Compounds chemistry
- Abstract
In the present work, a complete study of the sewage sludge (SS) biodrying technology was conducted at bench-scale, aiming at assessing its performance and providing a valuable insight into the different gaseous emission patterns found for greenhouse gases (GHG) and odorant pollutants. As process key parameters, temperature, specific airflow, dynamic respiration index, final moisture content and Lower Calorific Value (LCV) were evaluated. At the end of the biodrying, a product with a 35.9% moisture content and a LCV of 7.1 MJ·kg
-1 product was obtained. GHGs emission factor was 28.22 kgCO2eq per Mg of initial mass of dry matter in the SS (DM0 -SS). During the biodrying process, maximum odour concentration measured was 3043 ou·m-3 and the estimated odour emission factor of the biological treatment was 3.10E + 07 ou per Mg DM0 -SS. Finally, VOCs were completely identified and quantified. The most abundant VOCs found in the biodrying gaseous emissions were terpenes, sulphur-compounds and ketones., (Copyright © 2019 Elsevier Ltd. All rights reserved.)- Published
- 2019
- Full Text
- View/download PDF
27. Fate of pharmaceuticals and antibiotic resistance genes in a full-scale on-farm livestock waste treatment plant.
- Author
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Gros M, Marti E, Balcázar JL, Boy-Roura M, Busquets A, Colón J, Sànchez-Melsió A, Lekunberri I, Borrego CM, Ponsá S, and Petrovic M
- Subjects
- Anaerobiosis, Animals, DNA isolation & purification, Osmosis, Sewage, Wastewater, Agriculture, Drug Residues analysis, Drug Resistance, Microbial genetics, Livestock, Veterinary Drugs analysis, Waste Disposal, Fluid
- Abstract
This study investigated, for the first time, the distribution and fate of 28 multiple-class veterinary pharmaceuticals and antibiotics (PhACs), and their corresponding antibiotic resistance genes (ARGs), in a full-scale on-farm livestock waste treatment plant. The plant relies on several technologies, including: anaerobic digestion (AD), solid-liquid separation, and two stages reverse osmosis (RO) of the liquid digestate. Tetracycline, fluoroquinolone, lincosamide and pleuromutilin antibiotics, together with anti-helmintic (flubendazole) and anti-inflammatory (flunixin) drugs were the most frequently detected compounds in livestock waste and in slaughterhouse sludge. This last fraction is used as co-substrate in the AD process and showed to be an important input source of PhACs and ARGs. In terms of treatment performance, AD exhibited moderate to low PhACs and ARGs reduction, while a large fraction (<50%) of the PhACs present in the digestate were distributed onto the solid fraction, after solid-liquid separation. Both solid and liquid digestates had relatively high copy numbers of ARGs. Finally, RO showed high rejection percentages for all PhACs (<90%), with concentrations in the low ng L
-1 range in permeates, for most target PhACs. Nevertheless, moderate copy numbers of ARGs were detected in permeates., (Copyright © 2019 Elsevier B.V. All rights reserved.)- Published
- 2019
- Full Text
- View/download PDF
28. Effects of potash mining on river ecosystems: An experimental study.
- Author
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Cañedo-Argüelles M, Brucet S, Carrasco S, Flor-Arnau N, Ordeix M, Ponsá S, and Coring E
- Subjects
- Animals, Biomass, Complex Mixtures analysis, Diatoms, Ecology, Environmental Monitoring methods, Fresh Water, Invertebrates drug effects, Water Pollutants, Chemical analysis, Complex Mixtures pharmacology, Ecosystem, Mining, Rivers, Water Pollutants, Chemical pharmacology
- Abstract
In spite of being a widespread activity causing the salinization of rivers worldwide, the impact of potash mining on river ecosystems is poorly understood. Here we used a mesocosm approach to test the effects of a salt effluent coming from a potash mine on algal and aquatic invertebrate communities at different concentrations and release modes (i.e. press versus pulse releases). Algal biomass was higher in salt treatments than in control (i.e. river water), with an increase in salt-tolerant diatom species. Salt addition had an effect on invertebrate community composition that was mainly related with changes in the abundance of certain taxa. Short (i.e. 48 h long) salt pulses had no significant effect on the algal and invertebrate communities. The biotic indices showed a weak response to treatment, with only the treatment with the highest salt concentration causing a consistent (i.e. according to all indices) reduction in the ecological quality of the streams and only by the end of the study. Overall, the treatment's effects were time-dependent, being more clear by the end of the study. Our results suggest that potash mining has the potential to significantly alter biological communities of surrounding rivers and streams, and that specific biotic indices to detect salt pollution should be developed., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2017
- Full Text
- View/download PDF
29. Chloride and sulphate toxicity to Hydropsyche exocellata (Trichoptera, Hydropsychidae): Exploring intraspecific variation and sub-lethal endpoints.
- Author
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Sala M, Faria M, Sarasúa I, Barata C, Bonada N, Brucet S, Llenas L, Ponsá S, Prat N, Soares AMVM, and Cañedo-Arguelles M
- Subjects
- Animals, Environmental Monitoring, Industrial Waste analysis, Insecta growth & development, Larva drug effects, Larva growth & development, Spain, Toxicity Tests, Chlorides toxicity, Insecta drug effects, Sulfates toxicity, Water Pollutants, Chemical toxicity
- Abstract
The rivers and streams of the world are becoming saltier due to human activities. In spite of the potential damage that salt pollution can cause on freshwater ecosystems, this is an issue that is currently poorly managed. Here we explored intraspecific differences in the sensitivity of freshwater fauna to two major ions (Cl(-) and SO4(2-)) using the net-spinning caddisfly Hydropsyche exocellata Dufour 1841 (Trichoptera, Hydropsychidae) as a model organism. We exposed H. exocellata to saline solutions (reaching a conductivity of 2.5mScm(-1)) with Cl(-):SO4(2-) ratios similar to those occurring in effluents coming from the meat, mining and paper industries, which release dissolved salts to rivers and streams in Spain. We used two different populations, coming from low and high conductivity streams. To assess toxicity, we measured sub-lethal endpoints: locomotion, symmetry of the food-capturing nets and oxidative stress biomarkers. According to biomarkers and net building, the population historically exposed to lower conductivities (B10) showed higher levels of stress than the population historically exposed to higher conductivities (L102). However, the differences between populations were not strong. For example, net symmetry was lower in the B10 than in the L102 only 48h after treatment was applied, and biomarkers showed a variety of responses, with no discernable pattern. Also, treatment effects were rather weak, i.e. only some endpoints, and in most cases only in the B10 population, showed a significant response to treatment. The lack of consistent differences between populations and treatments could be related to the high salt tolerance of H. exocellata, since both populations were collected from streams with relatively high conductivities. The sub-lethal effects tested in this study can offer an interesting and promising tool to monitor freshwater salinization by combining physiological and behavioural bioindicators., (Copyright © 2016 Elsevier B.V. All rights reserved.)
- Published
- 2016
- Full Text
- View/download PDF
30. Carbon and water footprint of pork supply chain in Catalonia: From feed to final products.
- Author
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Noya I, Aldea X, Gasol CM, González-García S, Amores MJ, Colón J, Ponsá S, Roman I, Rubio MA, Casas E, Moreira MT, and Boschmonart-Rives J
- Subjects
- Animal Husbandry statistics & numerical data, Animals, Conservation of Natural Resources, Food Technology statistics & numerical data, Greenhouse Effect statistics & numerical data, Models, Statistical, Reproducibility of Results, Spain, Animal Feed analysis, Animal Husbandry methods, Carbon Footprint standards, Carbon Footprint statistics & numerical data, Food Technology methods, Meat Products analysis, Swine growth & development, Water Pollution analysis, Water Pollution statistics & numerical data
- Abstract
A systematic tool to assess the Carbon Footprint (CF) and Water Footprint (WF) of pork production companies was developed and applied to representative Catalan companies. To do so, a cradle-to-gate environmental assessment was carried out by means of the LCA methodology, taking into account all the stages involved in the pork chain, from feed production to the processing of final products, ready for distribution. In this approach, the environmental results are reported based on eight different functional units (FUs) according to the main pork products obtained. With the aim of ensuring the reliability of the results and facilitating the comparison with other available reports, the Product Category Rules (PCR) for Catalan pork sector were also defined as a basis for calculations. The characterization results show fodder production as the main contributor to the global environmental burdens, with contributions higher than 76% regardless the environmental indicator or the life cycle stage considered, which is in agreement with other published data. In contrast, the results in terms of CF and WF lay above the range of values reported elsewhere. However, major discrepancies are mainly due to the differences in the co-products allocation criteria. In this sense, economic/physical allocation and/or system expansion have been mostly considered in literature. In contrast, no allocation was considered appropriate in this study, according to the characteristics of the industries and products under assessment; thus, the major impacts fall on the main product, which derives on comparatively higher environmental burdens. Finally, due to the relevance of fodder production in the overall impact assessment results, strategies to reduce greenhouse gases (GHG) emissions as well as water use associated to this stage were proposed in the pork supply chain., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2016
- Full Text
- View/download PDF
31. Determining C/N ratios for typical organic wastes using biodegradable fractions.
- Author
-
Puyuelo B, Ponsá S, Gea T, and Sánchez A
- Subjects
- Biodegradation, Environmental, Carbon Dioxide metabolism, Manure microbiology, Refuse Disposal, Waste Disposal, Fluid, Carbon analysis, Nitrogen analysis
- Abstract
It is well established that an optimal aerobic and anaerobic microbial metabolism is achieved with a C/N ratio between 20 and 30. Most studies are currently based on chemically-measured carbon and nitrogen contents. However, some organic wastes can be composed of recalcitrant carbon fractions that are not bioavailable. To know the biodegradable C/N ratio, two different methods to determine the aerobic and anaerobic biodegradable organic carbon (BOCAE and BOCAN) are proposed and used to analyze a wide variety of different organic samples. In general, raw wastes and digested products have more amount of BOCAE. On the contrast, the samples collected after an aerobic treatment have higher content of BOCAN. In any case, all the BOC fractions are lower than the total organic carbon (TOC). Therefore, the C/N ratios based on BOC are always lower than the total C/N ratio based on the TOC measure. The knowledge of the real bioavailable C/N ratio is crucial for the biological treatments of organic materials. To reduce the test time necessary for BOC determination, the values of BOC for all the samples obtained at different times were compared and correlated with the final BOC. A method that allows for the determination of BOCAE in 4 d is proposed. In relation to the anaerobic assay, the biogas potential calculated after 21 and 50 d was positively correlated with the final potential defined after 100 d of assay., (Copyright © 2011 Elsevier Ltd. All rights reserved.)
- Published
- 2011
- Full Text
- View/download PDF
32. Modelling the aerobic degradation of organic wastes based on slowly and rapidly degradable fractions.
- Author
-
Ponsá S, Puyuelo B, Gea T, and Sánchez A
- Subjects
- Aerobiosis, Biodegradation, Environmental, Carbon metabolism, Carbon Dioxide metabolism, Cities, Kinetics, Nitrogen metabolism, Spain, Waste Products classification, Models, Biological, Organic Chemicals metabolism, Waste Management methods, Waste Products analysis
- Abstract
Several organic wastes of major production in the world (municipal solid wastes, wastewater sludge, manures and bulking agents) and some already treated organic wastes have been investigated to determine the partition among the several fractions that compose them and their kinetics of biodegradation. Different literature models have been explored for their suitability to predict the behaviour in respiration studies of these wastes. All the models presented limitations related to their simplicity or their excessive complexity, which makes them unsuitable for reliable and fast studies at real scale. A new model based on the rapid, the slowly and the inert organic fractions has been tested for all the wastes, showing excellent correlations with actual respiration activity. Finally, the kinetic parameters for this model in its application to all the wastes studied are presented., (Copyright © 2011 Elsevier Ltd. All rights reserved.)
- Published
- 2011
- Full Text
- View/download PDF
33. The effect of storage and mechanical pretreatment on the biological stability of municipal solid wastes.
- Author
-
Ponsá S, Gea T, and Sánchez A
- Subjects
- Aerobiosis, Anaerobiosis, Bioreactors, Cities, Environmental Pollutants, Organic Chemicals chemistry, Oxygen chemistry, Soil, Spain, Temperature, Biodegradation, Environmental, Refuse Disposal methods, Waste Management methods
- Abstract
Modern mechanical-biological waste treatment plants for the stabilization of both the source-separated organic fraction of municipal solid wastes (OFMSW) and the mixed stream of municipal solid wastes (MSW) include a mechanical pretreatment step to separate recyclable materials such as plastics, glass or metals, before biological treatment of the resulting organic material. In this work, the role of storage and mechanical pretreatment steps in the stabilization of organic matter has been studied by means of respiration techniques. Results have shown that a progressive stabilization of organic matter occurs during the pretreatment of the source-separated OFMSW, which is approximately 30% measured by the dynamic respiration index. In the case of mixed MSW, the stabilization occurring during the reception and storage of MSW is compensated by the effect of concentration of organic matter that the pretreatment step provokes on this material. Both results are crucial for the operation of the succeeding biological process. Finally, respiration indices have been shown to be suitable for the monitoring of the pretreatment steps in mechanical-biological waste treatment plants, with a strong positive correlation between the dynamic respiration index and the cumulative respiration index across all samples tested., (Copyright 2009 Elsevier Ltd. All rights reserved.)
- Published
- 2010
- Full Text
- View/download PDF
34. Different indices to express biodegradability in organic solid wastes.
- Author
-
Ponsá S, Gea T, and Sánchez A
- Subjects
- Biodegradation, Environmental, Oxygen Consumption, Organic Chemicals metabolism, Oxygen metabolism, Waste Products analysis
- Abstract
Respiration indices are suggested in literature as the most suitable stability determination and are proposed as a biodegradability measure in this work. An improved dynamic respiration index methodology is described in this work. This methodology was applied to 58 samples of different types of waste including municipal solid wastes and wastewater sludge, both raw materials and samples collected in a mechanical-biological treatment plant at different stages of biodegradation. The information obtained allowed to establish a qualitative classification of wastes in three categories: highly biodegradable, moderately biodegradable, and wastes of low biodegradability. Results were analyzed in terms of long and short-term indices and index expression: dynamic respiration indices expressed as average oxygen uptake rate (mg O(2) g(-1) dry matter [DM] h(-1)) at 1 and 24 h of maximum activity (DRI(1h), DRI(24h)); and cumulative oxygen consumption in 24 h of maximum activity and 4 d (AT(24h), AT(4)). The statistical comparison of indices and wastes is also presented. Raw sludge presented the highest biodegradability followed by the organic fraction of municipal solid waste and anaerobically digested sludge. All indices correlated well but different correlations were found for the different wastes analyzed. The information in the dynamic respiration profile allows for the calculation of different indices that provide complementary information. The combined analysis of DRI(24h) and AT(4) is presented here as the best tool for biodegradable organic matter content characterization and process requirements estimation.
- Published
- 2010
- Full Text
- View/download PDF
35. In search of a reliable technique for the determination of the biological stability of the organic matter in the mechanical-biological treated waste.
- Author
-
Barrena R, d'Imporzano G, Ponsá S, Gea T, Artola A, Vázquez F, Sánchez A, and Adani F
- Subjects
- Aerobiosis, Anaerobiosis, Oxygen metabolism, Reproducibility of Results, Organic Chemicals metabolism
- Abstract
The biological stability determines the extent to which readily biodegradable organic matter has decomposed. In this work, a massive estimation of indices suitable for the measurement of biological stability of the organic matter content in solid waste samples has been carried out. Samples from different stages in a mechanical-biological treatment (MBT) plant treating municipal solid wastes (MSW) were selected as examples of different stages of organic matter stability in waste biological treatment. Aerobic indices based on respiration techniques properly reflected the process of organic matter biodegradation. Static and dynamic respirometry showed similar values in terms of aerobic biological activity (expressed as oxygen uptake rate, OUR), whereas cumulative oxygen consumption was a reliable method to express the biological stability of organic matter in solid samples. Methods based on OUR and cumulative oxygen consumption were positively correlated. Anaerobic methods based on biogas production (BP) tests also reflected well the degree of biological stability, although significant differences were found in solid and liquid BP assays. A significant correlation was found between cumulative oxygen consumption and ultimate biogas production. The results obtained in this study can be a basis for the quantitative measurement of the efficiency in the stabilization of organic matter in waste treatment plants, including MBT plants, anaerobic digestion of MSW and composting plants.
- Published
- 2009
- Full Text
- View/download PDF
36. Comparison of aerobic and anaerobic stability indices through a MSW biological treatment process.
- Author
-
Ponsá S, Gea T, Alerm L, Cerezo J, and Sánchez A
- Subjects
- Aerobiosis, Anaerobiosis, Methane, Bioreactors, Refuse Disposal methods
- Abstract
A complex mechanical-biological waste treatment plant designed for the processing of mixed municipal solid wastes (MSW) and source-selected organic fraction of municipal solid wastes (OFMSW) has been studied by using stability indices related to aerobic (respiration index, RI) and anaerobic conditions (biochemical methane potential, BMP). Several selected stages of the plant have been characterized: waste inputs, mechanically treated wastes, anaerobically digested materials and composted wastes, according to the treatment sequence used in the plant. Results obtained showed that the main stages responsible for waste stabilization were the two first stages: mechanical separation and anaerobic digestion with a diminution of both RI and BMP around 40% and 60%, respectively, whereas the third stage, composting of digested materials, produced lesser biological degradation (20-30%). The results related to waste stabilization were similar in both lines (MSW and OFMSW), although the indices obtained for MSW were significantly lower than those obtained for OFMSW, which demonstrated a high biodegradability of OFMSW. The methodology proposed can be used for the characterization of organic wastes and the determination of the efficiency of operation units used in mechanical-biological waste treatment plants.
- Published
- 2008
- Full Text
- View/download PDF
37. Optimization of the hydrolytic-acidogenic anaerobic digestion stage (55 degrees C) of sewage sludge: influence of pH and solid content.
- Author
-
Ponsá S, Ferrer I, Vázquez F, and Font X
- Subjects
- Anaerobiosis, Hydrogen-Ion Concentration, Hydrolysis, Oxidation-Reduction, Water Pollutants, Chemical, Water Purification, Sewage chemistry
- Abstract
In conventional single-stage anaerobic digestion processes, hydrolysis is regarded as the rate-limiting step in the degradation of complex organic compounds, such as sewage sludge. Two-stage systems have been proposed to enhance this process. However, so far it is not clear which are the best conditions for a two-stage anaerobic digestion process of sewage sludge, in terms of temperature and hydraulic retention time of each stage. The aim of this work was to determine the optimal conditions for the hydrolytic-acidogenic stage treating real sludge with a high concentration of total solids (40-50gL(-1)) and volatile solids (25-30gL(-1)), named high concentration sludge. The variables considered for this first stage were: hydraulic retention time (1-4 days) and temperature (55 and 65 degrees C). Maximum volatile fatty acids generation was obtained at 4 days and 3 days hydraulic retention time for 55 degrees C and 65 degrees C, respectively. Consequently, 4 days hydraulic retention time and temperature of 55 degrees C were set as the working conditions for the hydrolytic-acidogenic stage treating high concentration sludge. The results obtained when operating with high concentration sludge were compared with a low concentration sludge consisting of 17-28gL(-1) total solids and 13-21gL(-1) volatile solids. The effect of decreasing the influent sludge pH, when working at the optimal conditions established, was also evaluated.
- Published
- 2008
- Full Text
- View/download PDF
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