Examinando por Autor "Puyol, Daniel"

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A novel photoanaerobic process as a feasible alternative to the traditional aerobic treatment of refinery wastewater
(Elsevier, 2022) San Martín, Javier; Puyol, Daniel; Segura, Yolanda; Melero, Juan A.; Martínez, Fernando
Refinery wastewater (RWW) treatment is outdated since new wastewater management and reuse challenges require more environmental-friendly and cheap alternatives. Conventional biological treatments focused on activated sludge are highly energy-intensive and resource-dissipating processes. However, anaerobic treatments are an excellent alternative to reduce costs derived from aeration and carbon footprint. This work proposes a novel strategy for the treatment of RWW involving a photoanaerobic membrane bioreactor (PAnMBR) with a mixed culture of purple phototrophic bacteria (PPB). PPB upcycles the organic matter, nitrogen, and phosphorus in an assimilative way, leading to a much higher biomass yield and nutrient removal than aerobic cultures. The enriched PPB culture was generated from the RWW as the sole substrate without specific PPB inoculation. The RWW (exempted from sufficient nutrients) was successfully treated with additional ammonium and phosphates provided by domestic wastewater (DWW). Preliminary batch tests determined the best DWW/RWW volumetric mixing ratio at 25:75. The PAnMBR was operated for 144 days under different specific loading rates (SLR) by modifying hydraulic and solid retention times. The maximum specific loading rate (SLR) for the efficient RWW/ DWW mix treatment was 0.3 mgCODinlet/mgCODbiomass⋅d. The COD consumption was mainly mediated by Rhodopseudomonas sp. and Rhodobacter sp. PPB genera. The PPB-based photo-anaerobic membrane reactor was able to comply with regulated parameters for wastewater discharge for the more restrictive use of reclaimed water according to the European legislation in force.
Anaerobic biodegradation of 2,4,6-trichlorophenol in expanded granular sludge bed and fluidized bed biofilm reactors bioaugmented with Desulfitobacterium spp.
(IWA Publishing, 2011-07-01) Puyol, Daniel; Rajhi, Hayfa; Mohedano, Angel F; Rodríguez, Juan José; Sanz, José Luis
The biodegradation of 2,4,6-trichlorophenol (246TCP) was studied using expanded granular sludge bed (EGSB) reactors and a fluidized bed biofilm reactor (FBBR) filled with activated carbon. One of the EGSB reactor and the FBBR were bioaugmented with Desulfitobacterium strains. 246TCP loading rate was gradually incremented from 10 to 250 mg L−1 day−1. The main pathway of dechlorination was in ortho-position, generating 4-chlorophenol and 2,4-dichlorophenol. The maintenance of both COD degradation efficiency (higher than 80%) and methanogenic efficiency (between 0.3 and 0.6 g CH4–COD g−1 COD consumed) in EGSB reactor implies a great stability of the process. Through isotherm studies in FBBR, it could be deduced that around 52% of 246TCP was completely dechlorinated, whereas the adsorption involved around 16%. By means of FISH studies it was proved that the methanogenic Archaea community was maintained in the bioaugmented EGSB reactor, whereas in the FBBR this community was gradually developed until reaching stability. Desulfitobacterium community was also maintained in the reactors, although D. chlororespirans proportion rise in the FBBR at the higher 246TCP loading rates, implying that this species can withstand the 246TCP toxicity better than D. hafniense
Biodiesel and biogas production from Isochrysis galbana using dry and wet lipid extraction: A biorefinery approach
(Elsevier, 2020) Sánchez-Bayo, Alejandra; López-Chicharro, Daniel; Morales, Victoria; Espada, Juan José; Puyol, Daniel; Martínez, Fernando; Astals, Sergi; Vicente, Gemma; Bautista, Luis Fernando; Rodríguez, Rosalía
Wet lipid extraction combined with residual biomass anaerobic digestion are alternatives to reduce the overall energy consumption of biodiesel production from microalgae. Solvents with different polarities have been studied to assess dry and wet lipid extraction process from Isochrysis galbana microalga. Ethyl acetate (EA) and a chloroform:methanol (CM) mixture yielded the best lipid extraction results in the dry and wet route with suitable lipid compositions. Fatty acid methyl esters (FAMEs) conversion of dry and wet extracted lipids with these solvents was performed by using both homogeneous (H2SO4) and heterogeneous (resin CT 269) catalysts. FAME production from wet extracted lipids with the EA solvent using the CT-269 resin constitutes an advantageous process because it avoids the water elimination step, and the CT-269 is a heterogeneous commercial catalyst, readily to separate after reaction. Lipid-spent microalga was anaerobically digested, obtaining that waste biomass from the wet extraction with EA had the highest methane yield (310 mL CH4/g volatile solids (VS). Energy balance analysis for FAMEs production with EA solvent (wet route) and heterogeneous catalyst yielded an energy recovery of about 80% in terms of biodiesel and biogas. Therefore, this process constitutes a promising route under an energy-driven microalga biorefinery.
Comparison of UASB and EGSB performance on the anaerobic biodegradation of 2, 4-dichlorophenol
(Elsevier, 2009-07-04) Puyol, Daniel; Mohedano, Angel F.; Sanz, José Luis; Rodríguez, Juan José
The anaerobic degradation of 2,4-dichlorophenol (2,4-DCP) in upflow anaerobic sludge blanket (UASB) and expanded granular sludge bed (EGSB) reactors using glucose as main carbon source was studied. The performance of both systems was compared in terms of 2,4-DCP and COD removal efficiencies, methane production, stability, granular sludge adaptability as well as reversion of the bacterial inhibition. Both organic and 2,4-DCP loading rates were incrementally varied through the experiments. With loading rates of 1.9 g COD L 1d 1 and 100mg 2,4-DCP L 1d 1, 75% and 84% removal efficiencies of this compound, accompanied by COD consumption efficiencies of 61% and 80% were achieved in the UASB and EGSB reactors, respectively. In these conditions, methane production reached 0.088 L CH4 g 1 COD in the EGSB reactor whereas in the UASB reactor was almost negligible. Decreasing the 2,4-DCP loading rate to 30 mgL 1d 1 an improvement in the methane production was observed in both reactors (methanogenic activity of 0.148 and 0.192 L CH4 g 1 COD in UASB and EGSB reactors, respectively). Efficiency of dechlorination was improved in both reactors from around 30% to 80% by reducing to one-half the COD due to a decreasing of the 4-chlorophenol concentration accumulated in the effluents of both reactors. The dechlorination efficiency of the UASB reactor was dramatically inhibited at a 2,4-DCP feed concentration above around 210 mg L 1 because of 2,4-DCP accumulation in the effluent. SEM studies revealed no significant morphological changes in the sludge granules.
Contamination of N-poor wastewater with emerging pollutants does not affect the performance of purple phototrophic bacteria and the subsequent resource recovery potential
(2020) Martínez, Fernando; de las Heras, Igor; Molina, Raúl; Segura, Yolanda; Hülsen, Tim; Molina, María Carmen; Gonzalez-Benítez, Natalia; Melero, Juan Antonio; Mohedano, Ángel F.; Puyol, Daniel
Propagation of emerging pollutants (EPs) in wastewater treatment plants has become a warning sign, especially for novel resource-recovery concepts. The fate of EPs on purple phototrophic bacteria (PPB)-based systems has not yet been determined. This work analyzes the performance of a photo-anaerobic membrane bioreactor treating a low-N wastewater contaminated with 25 EPs. The chemical oxygen demand (COD), N and P removal efficiencies were stable (76 ± 8, 62 ± 15 and 36 ± 8 %, respectively) for EPs loading rate ranging from 50 to 200 ng L-1 d-1. The PPB community adapted to changes in both the EPs concentration and the organic loading rate (OLR) and maintained dominance with >85 % of total 16S gene copies. Indeed, an increment of the OLR caused an increase of the biomass growth and activity concomitantly with a higher EPs removal efficiency (30 ± 13 vs 54 ± 11 % removal for OLR of 307 ± 4 and 590 ± 8 mgCOD L-1 d-1, respectively). Biodegradation is the main mechanism of EPs removal due to low EPs accumulation on the biomass, the membrane or the reactor walls. Low EPs adsorption avoided biomass contamination, resulting in no effect on its biological methane potential. These results support the use of PPB technologies for resource recovery with low EPs contamination of the products.
Cosmetic wastewater treatment by upflow anaerobic sludge blanket reactor
(Elsevier, 2011) Puyol, Daniel; Monsalvo, Victor M.; Mohedano, Ángel F.; Sanz, José Luis; Rodríguez, Juan José
Anaerobic treatment of pre-settled cosmetic wastewater in batch and continuous experiments has been investigated. Biodegradability tests showed high COD and solid removal efficiencies (about 70%), being the hydrolysis of solids the limiting step of the process. Continuous treatment was carried out in an upflow anaerobic sludge blanket reactor. High COD and TSS removal efficiencies (up to 95% and 85%, respectively) were achieved over a wide range of organic load rate (from 1.8 to 9.2 g TCOD L−1 day−1). Methanogenesis inhibition was observed in batch assays, which can be predicted by means of a Haldane-based inhibition model. Both COD and solid removal were modelled by Monod and pseudo-first order models, respectively.
Effect of 2,4,6-trichlorophenol on the microbial activity of adapted anaerobic granular sludge bioaugmented with Desulfitobacterium strains
(Elsevier, 2011-12-15) Puyol, Daniel; Mohedano, Angel F.; Rodríguez, Juan José; Sanz, José Luis
The anaerobic degradation of 2,4,6-trichlorophenol (246TCP) has been studied in batch experiments. Granular sludges previously acclimated to 2,4-dichlorophenol (24DCP) and then adapted to at a load of 330 μM 246TCP d−1 in two expanded granular sludge bed (EGSB) reactors were used. One of the reactors had been bioaugmented with Desulfitobacterium strains whereas the other served as control. 246TCP was tested at concentrations between 250 and 760 μM. The study focused on the fate of both fermentation products and chlorophenols derived from dechlorination of 246TCP. This compound mainly affected the biodegradation of acetate and propionate, which were inhibited at 246TCP concentrations above 380 μM. Lactate and ethanol were also accumulated at 760 μM 246TCP. Methanogenesis was strongly inhibited at 246TCP concentrations higher than 380 μM. A diauxic production of methane was observed, which can be described by a kinetic model in which acetoclastic methanogenesis was inhibited, whereas hydrogenotrophic methanogenesis was hardly affected by 246TCP. The similarity of the kinetic parameters obtained for the control and the bioaugmented sludges (Ki = 175–200 μM 246TCP and n = 7) suggests that methanogenesis is not affected by the bioaugmentation. Moreover, the 246TCP dechlorination occurred mainly at ortho position, successively generating 24DCP and 4-chlorophenol (4CP), which was identified as final product. The bioaugmentation does not significantly improve the anaerobic biodegradation of 246TCP. It has been shown that the active biomass is capable of bioaccumulating 246TCP and products from dechlorination, which are subsequently excreted to the bulk medium when the biomass becomes active again. A kinetic model is proposed which simultaneously explains 246TCP and 24DCP reductive dechlorinations and includes the 246TCP bioaccumulation. The values of the kinetic parameters for 246TCP dechlorination were not affected by bioaugmentation (Vmax = 5.3 and 5.1 μM h−1 and Ks = 5.8 and 13.1 μM for control and bioaugmented sludges, respectively)
Environmental life cycle assessment of polyhydroxyalkanoates production by purple phototrophic bacteria mixed cultures
(Elsevier, 2023) Martin-Gamboa, Mario; Allegue, Luis D.; Puyol, Daniel; Melero, Juan Antonio; Dufour, Javier
Bioplastics offer a promising sustainable alternative to petroleum-based plastics due to their biodegradability as well as favourable thermal and mechanical properties. Among different types of biobased polymers, the production of polyhydroxyalkanoates (PHA) using purple phototrophic bacteria (PPB) and low-value substrates has gained increasing interest. Despite the momentum, challenges regarding the scalability and environmental feasibility of this biopolymer production pathway remain. In response, this study employs an exploratory LCA approach to quantitatively assesses the potential environmental implications of PHA production in powder form and the joint management of the organic fraction of municipal solid waste (OFMSW) through a novel photobiorefinery system that uses PPB mixed cultures. Environmental impacts were tested under multiple improvement scenarios and benchmarked against the production of conventional fossil-based granulate or unprocessed plastics, including low density polyethylene (LDPE), polyethylene terephthalate (PET) and polyurethane (PU). The photobiorefinery stage was found to have the greatest contribution to the impact categories, particularly due to direct emissions, consumption of electricity and production of extractive chemical agents used. These factors accounted for over 70% of the photobiorefinery impact in all cases. Avoided impacts provided net favourable outcomes in terms of carbon footprint and fossil resources when comparing PHA production to conventional plastics, especially PET and PU, with impact reductions ranging from 30% to 60%, respectively. However, when considering other impact categories like eutrophication, this situation was less favourable. The exploration of alternative scenarios offered significant impact reductions, especially when renewable electricity or an environmentally friendly extraction agent is used. Moreover, minimizing methane losses or co-producing hydrogen in the photobiorefinery had a notably positive effect on the carbon footprint, reducing the impact by more than 2 t of CO2 eq per t of PHA powder compared to the base case. Therefore, the implementation of feasible improvement measures in the short term can position PHA produced by mixed cultures as a sustainable alternative to petroleum-based plastics.
Exploring the effects of ZVI addition on resource recovery in the anaerobic digestion process
(2018) Puyol, Daniel; Flores Alsina, Xavier; Segura, Yolanda; Molina, Raúl; Padrino, Beatriz; Fierro, Jose Luis G.; Gernaey, Krist V.; Melero, Juan Antonio; Martínez, Fernando
The influence of Zero Valent Iron (ZVI) addition on the potential resource recovery during the anaerobic digestion (AD) of domestic waste sludge is assessed. Potentially recoverable resources analyzed were nutrients such as struvite to recover P, and energy as biogas to recover C. Short term (biochemical methane potential tests, BMP) and long term (AD1, AD2) experiments are conducted using two types of set-up (batch, continuous). Process data (influent, effluent and biogas) is continuously collected and the dry digested sludge is analyzed by XPS. A mathematical model is developed based on a modified version of the Anaerobic Digestion Model No 1 upgraded with an improved physicochemical description, ZVI corrosion, propionate uptake enhancement and multiple mineral precipitation. The results of all experiments show that ZVI addition increases methane production and promotes the formation of siderite (FeCO3) and vivianite (Fe3(PO4)2), which causes changes in the biogas composition (%CH4 versus %CO2) and reduces P release. The model can satisfactorily reproduce the dynamics of AD processes, nutrient release, pH and methanogenesis in AD1. The proposed approach also describes the changes in the overall performance of the process because of ZVI addition in AD2. A model-based scenario analysis is included balancing chemical-ZVI addition and increased methane production/struvite precipitation. This scenario analysis allows concluding that: (a) the improvement of methane production does not compensate the costs of ZVI purchase, and (b) ZVI dramatically decreases the P recovery potential in the digestate of the AD systems. This is the first study to experimentally and mathematically describe the effect of ZVI on biogas production/composition and on the fate of phosphorus compounds, and its potential implications for potential energy and phosphorus recovery in AD systems.
Thermal hydrolysis of solid fraction reduces waste disposal and provides a substrate for anaerobic photobiological treatment of refinery wastewater
(Royal Society of Chemistry, 2023-02-15) Jerez, Sara; San Martín, Javier; Ventura, Maria; Pariente, Maria Isabel; Segura, Yolanda; Puyol, Daniel; Molina, Raúl; Melero, Juan Antonio; Martinez, Fernando
Oil refineries generate vast amounts of refinery wastewater (RWW) and oily sludge (OS). Conventional treatments typically manage these effluents separately, and resource recovery potential is not considered. The thermal hydrolysis (TH) of oily sludge at different temperatures from 175 to 200 °C and several hydrolysis times from 30 to 90 minutes has been assessed. The TH reduced the solid fraction of the oily sludge by up to 50% and released substrates in the liquid stream with up to 14 g L−1 of soluble chemical oxygen demand (SCOD) and 592 mg L−1 of NH4+-N. Additionally, the hydrolyzed fraction was assessed as a substrate for the biological treatment of the refinery wastewater. An anaerobic photobiological system based on purple phototrophic bacteria (PPB) was considered to evaluate the co-treatment of both effluents. Batch experiments showed a 10- to 30-fold enhancement of the biomass yield, using both the RWW and the hydrolyzed fraction of the oily sludge. The less energetic TH conditions in terms of temperature and operation time produced the most biodegradable hydrolyzed stream with biomass yields close to those obtained for the control under optimal growth conditions. These results demonstrate the feasibility of the proposed integrated strategy to reduce the solid fraction of the oily sludge by the TH process and to release soluble substrates for a novel anaerobic photobiological treatment along with the RWW.
Towards biohydrogen overproduction and valorization of food waste by genetic engineering of Rhodobacter capsulatus
(2024-09) Valverde- Cañas, Ángel; Cuesta- Belvis, Daniel; Cicimov, Viktor; de Nicolás, Amanda P.; Díez, Mario P.; Díaz, Elena; de la Rubia, María Ángeles; Mohedano, Ángel F.; Puyol, Daniel; Barahona , Emma
Non-sulfur red bacteria, such as Rhodobacter capsulatus, produce H2 through photofermentation via nitrogenase. These bacteria offer several advantages over other hydrogen bioproduction systems, including high substrate conversion efficiency, the use of a wide variety of carbon sources, the ability to operate under environmental conditions, reduced energy consumption, and high purity of the hydrogen produced. Despite these advantages, higher production rates and more economical carbon sources are required to compete with conventional H2 production methods. For this reason, our ongoing work focuses on two main objectives: genetically redesigning R. capsulatus to increase its H2 production rates, and optimizing and improving the process by valorizing the material and energy content of food waste. In the H2 production experiments with R. capsulatus, both the wild-type strain and a mutant defective in uptake hydrogenase (ΔhupAB) were evaluated. Process water obtained from the hydrothermal carbonization of food waste and a minimal RCV medium were used as substrates in the photofermentation process. The experiments were carried out in batch mode under continuous illumination. The highest levels of H2 production were observed under the condition where the hupAB mutant was growing in RCV medium without a nitrogen source (almost 110 mL of H2/gCOD). However, H2 production values were similar to those obtained using process water as a substrate during the first 24 hours, thereby demonstrating that R. capsulatus can produce H2 from food waste.
Unraveling PHA production from urban organic waste with purple phototrophic bacteria via organic overload
(Elsevier, 2022-09-01) Diaz Allegue, Luis; Ventura, Maria; Melero, Juan Antonio; Puyol, Daniel
The production of polyhydroxyalkanoates (PHA) with purple phototrophic bacteria (PPB) has been limited due to low yields and limited knowledge regarding the diverse routes used for carbon biosynthesis. The present study increases PHA accumulation yields using urban organic waste pretreated by steam explosion and acidogenic fermentation as substrate. Throughout the PPB-based photoheterotrophic process in an anaerobic membrane photobioreactor, the organic loading rate (OLR) was modified to increase the amount of PHA and biomass in the reactor. A maximum PHA accumulation of 42% (g(PHA gBiomass)(-1)) on a dry basis was achieved and maintained for 10 d for an OLR of 1 gCOD L-1 d(-1), and hydraulic and sludge retention times of 2 and 6 d, respectively. This PHA accumulation capacity is the maximum obtained using a mixed culture of PPB fed with waste. Also, a medium-chain PHA (polyhydroxyhexanoate) has been quantified, enhancing the physicochemical properties and diversifying their industrial applications. Furthermore, we show novel alternatives to PHA accumulation: carbon storage as glycogen and extracellular polymers while deriving the excess electrons into hydrogen. Finally, a statistical study of microbial communities has settled the environmental variables with the most significant influence on these communities' variability. This work demonstrates the importance of acquiring a thorough understanding of carbon accumulation and electron allocation strategies of PPB under stressful conditions and shows promising results for a larger scale implementation of a PPB-based photobiorefinery, which could valorize urban organic waste to produce different high added-value products within the context of the circular bioeconomy.
Using inorganic acids to stop purple phototrophic bacteria metabolism improves PHA recovery at a large scale
(Springer, 2023) Srivastava, Pratiksha; Villamil, John A.; Melero, Juan A.; Martínez, Fernando; Puyol, Daniel
Polyhydroxyalkanoate (PHA) production at a large scale by purple phototrophic bacteria (PPB) is hindered due to high production costs and limited recovery due to its consumption during starvation periods. The present study identifed costefective inorganic acids as inactivation methods for PPB to obtain higher PHA recovery. The study was performed on reactors of diferent scales (10 L and 0.5 L) to grow PPB and recover PHA subsequently. The permanent feast strategy was adopted to obtain higher PHA in an anaerobic environment. As a result, the study achieved 33% (dry weight) PHA recovery using inorganic acid inactivation, while formaldehyde inactivation (traditional method) achieved signifcantly lower PHA recovery (20% only). The results from inorganic acid inactivation were further examined for their stability. The samples were stable even after day 14, and the PHA recovery was the same as on day 0. This pioneering study shows that inorganic acids can be used to inactivate the PPB metabolism to obtain higher PHA recovery; inorganic acid inactivation could be economical for large-scale PHA production.