Phycoremediation of municipal wastewater by microalgae to produce biofuel

Municipal wastewater (WW), if not properly remediated, poses a threat to the environment and human health by carrying significant loads of nutrients and pathogens. These contaminants pollute rivers, lakes and natural reservoirs where they cause eutrophication and pathogen-mediated diseases. However, the high nutrient content of WW makes it an ideal environment for remediation with microalgae that require high nutrient concentrations for growth and are not susceptible to toxins and pathogens. Given that an appropriate algal strain is used for remediation, the incurred biomass can be refined for the production of biofuel. Four microalgal species (Chlamydomonas reinhardtii, Chlorella sp., Parachlorella kessleri-I and Nannochloropsis gaditana) were screened for efficient phycoremediation of municipal WW and potential use for biodiesel production. Among the four strains tested, P. kessleri-I showed the highest growth rate and biomass production in 100% WW. It efficiently removed all major nutrients with a removal rate of up to 98% for phosphate after ten days of growth in 100% municipal WW collected from Delhi. The growth of P. kessleri-I in WW resulted in a 50% increase of biomass and a 115% increase of lipid content in comparison to growth in control media. The FAME and fuel properties of lipids isolated from cells grown in WW complied with international standards. The present study provides evidence that the green alga P. kessleri-I effectively remediates municipal WW and can be used to produce biodiesel

The effect of the introduction of Nile tilapia ( Oreochromis niloticus , L.) on small indigenous fish species (mola, Amblypharyngodon mola , Hamilton; chela, Chela cachius , Hamilton; punti, Puntius sophore , Hamilton)

This is the first controlled experiment to quantify the effect of introduced tilapia on indigenous species. This experiment was conducted in small earthen ponds (100 m 2 ) to assess the impact of mixed-sex or all-male Nile tilapia ( Oreochromis niloticus ) on small indigenous species (SIS) commonly found in south Asia, mola ( Amblypharyngodon mola ), chela ( Chela cachius ) and punti ( Puntius sophore ). Ponds were fertilized, then stocked with 0.56 fish m −2 of water surface area in the mixed-sex and all-male tilapia treatments and 0.42 fish m −2 in the treatment without tilapia. No additional nutritional inputs were applied after stocking. Treatments were: mixed-sex tilapia with SIS, mono-sex male tilapia with SIS and SIS without tilapia (control). All treatments were stocked with 14 fish per species. All species reproduced during the 21-month culture duration. The number of recruits varied by species, Tilapia reproduced in greater numbers than SIS. Tilapia numbers at harvest were the highest (451 ± 25/100 m 2 ) in the mixed-sex treatment compared with mola (221 ± 22/100 m 2 ), chela (94 ± 8/100 m 2 ) and punti (100 ± 7/100 m 2 ). The number of mola was higher (399 ± 33/100 m 2 ) in the all-male tilapia treatment. There was reduction in the number of mola and chela in the treatment containing mixed-sex tilapia. Gut content analysis combined with water sampling revealed that all fish species fed selectively. Significant interspecies dietary overlap was found between Nile tilapia and SIS and among SIS. Thus, there is potential for tilapia to compete with indigenous fish species when space and other resources are limiting, but a longer duration study with varying level of management is needed to determine how successfully tilapia competes with locally adapted SIS.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/79201/1/j.1365-2109.2009.02372.x.pd

Modeling the decay of nitrite oxidizing bacteria under different reduction potential conditions

[EN] Autotrophic growth and decay rates of ammonium and nitrite oxidizing bacteria (AOB and NOB, respectively) have a significant impact on the design and on the process performance of wastewater treatment systems where nitrification occurs. Literature data on the separate decay rates of AOB and NOB is scarce and inconsistent. In this study, batch experiments based on respirometric techniques were conducted to determine the NOB decay rates under different oxidation-reduction potential conditions, in order to widen the understanding of nitrite dynamics. The decay rate measured under anoxic conditions was 85% lower than under aerobic conditions, whereas under anaerobic conditions the decay rate reduction was 92%. A design and simulation tool was used to assess the impact of applying these results in differentiated areas of an activated sludge system. Simulations show a greater impact for systems with a sludge retention time under 10 days, for which up to a 16-fold increase in NOB biomass concentration and up to 86% and 80% reductions in ammonium and nitrite concentrations in the effluent were calculated. Therefore, this work demonstrates that considering different decay rates for autotrophic biomass under different ORP conditions avoids underestimating system performance and over dimensioning new activated sludge schemes.This research project has been supported by the Spanish Ministry of Economy, Industry and Competitiveness (MINECO,project CTM2017-86751-C2), whose support is gratefully acknowledged.Ruiz Martinez, A.; Claros Bedoya, JA.; Serralta Sevilla, J.; Bouzas Blanco, A.; Ferrer, J. (2018). Modeling the decay of nitrite oxidizing bacteria under different reduction potential conditions. Process Biochemistry. 71:159-165. https://doi.org/10.1016/j.procbio.2018.05.021S1591657

Effect of filter media thickness on the performance of sand drying beds used for faecal sludge management

The effect of sand filter media thickness on the performance of faecal sludge (FS) drying beds was determined in terms of: dewatering time, contaminant load removal efficiency, solids generation rate, nutrient content and helminth eggs viability in the dried sludge. A mixture of VIP-latrine sludge and septage in the ratio 1:2 was dewatered using three pilot-scale sludge drying beds with sand media thicknesses of 150 mm, 250 mm and 350 mm. Five dewatering cycles were conducted and monitored for each drying bed. Although 150 mm filter had the shortest average dewatering time of 3.65 days followed by 250 mm and 350 mm filters with 3.83 and 4.02 days, respectively, there was no significant difference ( p > 0.05) attributable to filter media thickness configurations. However, there was a significant difference for the percolate contaminant loads in the removal and recovery efficiency of suspended solids, total solids, total volatile solids, nitrogen species, total phosphorus, COD, DCOD and BOD, with the highest removal efficiency for each parameter achieved by 350 mm filter. There were also significant differences in the nutrient content (NPK) and helminth eggs viability of the solids generated by the tested filters. Filtering media configurations similar to 350 mm have the greatest potential for optimising nutrient recovery from FS

Fermentation brines from Spanish style green table olives processing: treatment alternatives previous to recycling or recovery operations

This is the peer reviewed version of the following article: Ferrer-Polonio, E., Iborra-Clar, A., Mendoza-Roca, J. A. and Pastor-Alcañiz, L. (2016), Fermentation brines from Spanish style green table olives processing: treatment alternatives before recycling or recovery operations. J. Chem. Technol. Biotechnol., 91: 131–137, which has been published in final form at http://dx.doi.org/10.1002/jctb.4550. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.BACKGROUND Fermentation brine from Spanish style green table olives processing (FTOP) is characterized by very high conductivity (around 88 mS cm(-1)), high values of suspended solids (near 1300 mg L-1), chemical oxygen demand (around 17 900 mg L-1) and total phenols (1000 mg L-1). In this work, fermentation brines have been exhaustively characterized and pH adjustment-sedimentation, coagulation-flocculation-sedimentation and adsorption with activated carbon have been evaluated. RESULTS AND CONCLUSIONS The pretreatment selection will depend on the final FTOP management. If no polyphenols elimination is required in view of a further recovery, the best pretreatment is pH adjustment to 9 plus sedimentation. The removal efficiencies achieved were 33.1% suspended solids, 82.5% turbidity and only 10.4% of polyphenols. However, if the final FTOP treatment was biological, the best pretreatment is adsorption with powder active carbon, because this pretreatment implies the maximum reduction of phenols in FTOP, which inhibit microorganism activity in the biological process. The maximum total phenols removal efficiency was 96% with 8 g L-1 of BM8 powder activated carbon (21% soluble COD).The authors of this work thank CDTI (Centre for Industrial Technological Development) for financial support through the Spanish Ministry of Science and Innovation. The authors thank Chiemevall and Derypol for support during this work.Ferrer-Polonio, E.; Iborra Clar, A.; Mendoza Roca, JA.; Pastor Alcañiz, L. (2016). Fermentation brines from Spanish style green table olives processing: treatment alternatives previous to recycling or recovery operations. Journal of Chemical Technology and Biotechnology. 91(1):131-137. doi:10.1002/jctb.4550S13113791

Biodegradation of olive washing wastewater pollutants by highly efficient phenol-degrading strains selected from adapted bacterial community

The bacterial community of an olive washing water (OWW) storage basin was characterized, by both cultivation and cultivation-independent methods. PCR-TGGE fingerprints analysis of different samples, taken along the olive harvesting season, revealed important variations of the bacterial community structure showing rapid establishment of prevalent bacterial populations. Several bacteria, isolated from OWW, were cultivated, in media containing increasing amounts of polyphenols, in order to select high phenol-degrading strains for the effluent pollutants reduction. Strains PM3 and PM15, affiliated to Raoultella terrigena and Pantoea agglomerans by 16S rRNA gene sequencing, were selected and used for OWW biological treatment under batch conditions in shake flasks cultures. The OWW content of phenols, BOD5, COD and colour, was reduced by 93, 91, 89 and 62%, respectively, permitting effluent disposal and/or reuse with no additional treatments.This research was supported by European project Algatec (FP7/SME/2008/1/232331)

Modelling approach to an ultrafiltration process for the removal of dissolved and colloidal substances from treated wastewater for reuse in recycled paper manufacturing

[EN] In this work, ultrafiltration (UF) is used to remove dissolved and colloidal substances (DCS) from a secondary clarifier effluent from a wastewater treatment plant (WWTP) in a papermaking factory. The approach has been to examine and model the decline in permeate flux resulting from membrane fouling. Effluent from a WWTP at a papermaking factory, previously filtered, was used as feed. UF experiments were carried out in a laboratory-scale plant using a 10 kDa polyethersulfone (PES) UF membrane in a flat sheet module with an active area of 154.8 cm(2). The transmembrane pressure (TMP) (1-3 bar) and crossflow rate (1.5-4.5 L/min) were varied during the experiments, at constant temperature (22 +/- 0.5 degrees C). Experimental results from UF tests were expressed in terms of permeate flux (Jp) as a function of time to check modified Hermia's models adapted to crossflow filtration. The parameters of these models were theoretically estimated. The predicted results were compared with experimental data with a high goodness of fit. The results showed that the phenomenon controlling fouling, under most of the conditions tested, was intermediate blocking (R-2 > 0.96). Measurements of particle size distribution and zeta potential near the isoelectric point, showed a substantial reduction in colloidal compounds. Additionally, given that COD was removed down to 110 mg/L, it could be said that UF is suitable for producing water that can be reused in different papermaking processes.The Euro-Brazilian Windows + project (with financial support granted by the European Commission through the Erasmus Mundus Programme).Santos-Sousa, MR.; Lora-García, J.; López Pérez, MF. (2018). Modelling approach to an ultrafiltration process for the removal of dissolved and colloidal substances from treated wastewater for reuse in recycled paper manufacturing. Journal of Water Process Engineering. 21:96-106. https://doi.org/10.1016/j.jwpe.2017.11.017S961062

Environmental effects of a marine fish farm of gilthead seabream (Sparus aurata) in the NW Mediterranean Sea on water column and sediment

This study examined the effects of organic enrichment on water column, sediments and macrofauna caused by a fish farm in the Mediterranean Sea. Samples were collected on four sampling campaigns over a one-year cycle. Significant differences were found in the water column in dissolved oxygen, dissolved inorganic nitrogen, phosphate and total phosphorus concentrations between the fish farm and the control. The increase in the dissolved inorganic nitrogen and phosphate concentrations at the fish farm modified the stoichiometric ratios between nutrients, with silicate acting as limiting nutrient at the fish farm 11% more than at the control. Nevertheless, chlorophyll a concentration in the water column was higher at the control station, probably due to the fouling of the underwater fish farm structures. Significant differences were found in sediment concentrations of organic matter, total phosphorus and redox potential between the fish farm and the control. The Canonical Correlation Analysis indicated that organic matter, total phosphorus, redox potential and% of gravels accounted for 68.9% of the total variance in the species data. Changes were observed in macrofauna, with a decrease in number of species and up to a nine-fold increase in abundance with respect to the control. © 2013 Blackwell Publishing Ltd.We would like to thank the Caja del Mediterraneo (CAM) for a pre-doctoral fellowship fund for this research and Antonio Asuncion Acuigroup Maremar Manager, for the facilities and support in conducting the study. The translation of this paper was funded by the Universidad Politecnica de Valencia, Spain.Morata Higón, T.; Falco Giaccaglia, SL.; Gadea, I.; Sospedra Ciscar, J.; Rodilla Alamá, M. (2013). Environmental effects of a marine fish farm of gilthead seabream (Sparus aurata) in the NW Mediterranean Sea on water column and sediment. 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G., Black, K., Bodoy, A., Emblow, C., Fernandes, T. F., … Angel, D. (2009). Assessing the suitability of a range of benthic indices in the evaluation of environmental impact of fin and shellfish aquaculture located in sites across Europe. Aquaculture, 293(3-4), 231-240. doi:10.1016/j.aquaculture.2009.04.037Braeckman, U., Provoost, P., Gribsholt, B., Van Gansbeke, D., Middelburg, J., Soetaert, K., … Vanaverbeke, J. (2010). Role of macrofauna functional traits and density in biogeochemical fluxes and bioturbation. Marine Ecology Progress Series, 399, 173-186. doi:10.3354/meps08336Chou, C. L., Haya, K., Paon, L. A., Burridge, L., & Moffatt, J. D. (2002). Aquaculture-related trace metals in sediments and lobsters and relevance to environmental monitoring program ratings for near-field effects. Marine Pollution Bulletin, 44(11), 1259-1268. doi:10.1016/s0025-326x(02)00219-9Christensen, P., Rysgaard, S., Sloth, N., Dalsgaard, T., & Schwærter, S. (2000). Sediment mineralization, nutrient fluxes, denitrification and dissimilatory nitrate reduction to ammonium in an estuarine fjord with sea cage trout farms. Aquatic Microbial Ecology, 21, 73-84. doi:10.3354/ame021073Chung, I.-K., Kang, Y.-H., Yarish, C., George, P. K., & Lee, J.-A. (2002). Application of Seaweed Cultivation to the Bioremediation of Nutrient-Rich Effluent. ALGAE, 17(3), 187-194. doi:10.4490/algae.2002.17.3.187Cromey, C. J., Nickell, T. D., & Black, K. D. (2002). DEPOMOD—modelling the deposition and biological effects of waste solids from marine cage farms. Aquaculture, 214(1-4), 211-239. doi:10.1016/s0044-8486(02)00368-xCugier, P., Struski, C., Blanchard, M., Mazurié, J., Pouvreau, S., Olivier, F., … Thiébaut, E. (2010). Assessing the role of benthic filter feeders on phytoplankton production in a shellfish farming site: Mont Saint Michel Bay, France. Journal of Marine Systems, 82(1-2), 21-34. doi:10.1016/j.jmarsys.2010.02.013Davies, I. M., McHenery, J. G., & Rae, G. H. (1997). Environmental risk from dissolved ivermectin to marine organisms. Aquaculture, 158(3-4), 263-275. doi:10.1016/s0044-8486(97)00209-3Dean, R. J., Shimmield, T. M., & Black, K. D. (2007). Copper, zinc and cadmium in marine cage fish farm sediments: An extensive survey. Environmental Pollution, 145(1), 84-95. doi:10.1016/j.envpol.2006.03.050Delgado, O., Ruiz, J., Pérez, M., Romero, J., & Ballesteros, E. (1999). Effects of fish farming on seagrass (Posidonia oceanica) in a Mediterranean bay: seagrass decline after organic loading cessation. Oceanologica Acta, 22(1), 109-117. doi:10.1016/s0399-1784(99)80037-1Dell’Anno, A., Mei, M. ., Pusceddu, A., & Danovaro, R. (2002). Assessing the trophic state and eutrophication of coastal marine systems: a new approach based on the biochemical composition of sediment organic matter. Marine Pollution Bulletin, 44(7), 611-622. doi:10.1016/s0025-326x(01)00302-2Ferrón, S., Ortega, T., & Forja, J. M. (2009). Benthic fluxes in a tidal salt marsh creek affected by fish farm activities: Río San Pedro (Bay of Cádiz, SW Spain). Marine Chemistry, 113(1-2), 50-62. doi:10.1016/j.marchem.2008.12.002Garren, M., Smriga, S., & Azam, F. (2008). Gradients of coastal fish farm effluents and their effect on coral reef microbes. Environmental Microbiology, 10(9), 2299-2312. doi:10.1111/j.1462-2920.2008.01654.xHolmer, M., & Kristensen, E. (1992). Impact of marine fish cage farming on metabolism and sulfate reduction of underlying sediments. Marine Ecology Progress Series, 80, 191-201. doi:10.3354/meps080191Holmer, M., Wildish, D., & Hargrave, B. (s. f.). Organic Enrichment from Marine Finfish Aquaculture and Effects on Sediment Biogeochemical Processes. Environmental Effects of Marine Finfish Aquaculture, 181-206. doi:10.1007/b136010Huang, Y., Hsieh, H., Huang, S., Meng, P., Chen, Y., Keshavmurthy, S., … Chen, C. (2011). Nutrient enrichment caused by marine cage culture and its influence on subtropical coral communities in turbid waters. Marine Ecology Progress Series, 423, 83-93. doi:10.3354/meps08944Johansson, O., & Wedborg, M. (1980). The ammonia-ammonium equilibrium in seawater at temperatures between 5 and 25�C. Journal of Solution Chemistry, 9(1), 37-44. doi:10.1007/bf00650135Johansson, D., Juell, J.-E., Oppedal, F., Stiansen, J.-E., & Ruohonen, K. (2007). The influence of the pycnocline and cage resistance on current flow, oxygen flux and swimming behaviour of Atlantic salmon (Salmo salar L.) in production cages. Aquaculture, 265(1-4), 271-287. doi:10.1016/j.aquaculture.2006.12.047Juell, J.-E., & Fosseidengen, J. E. (2004). Use of artificial light to control swimming depth and fish density of Atlantic salmon (Salmo salar) in production cages. Aquaculture, 233(1-4), 269-282. doi:10.1016/j.aquaculture.2003.10.026Justić, D., Rabalais, N. N., Turner, R. E., & Dortch, Q. (1995). Changes in nutrient structure of river-dominated coastal waters: stoichiometric nutrient balance and its consequences. Estuarine, Coastal and Shelf Science, 40(3), 339-356. doi:10.1016/s0272-7714(05)80014-9Karakassis, I., Tsapakis, M., & Hatziyanni, E. (1998). Seasonal variability in sediment profiles beneath fish farm cages in the Mediterranean. Marine Ecology Progress Series, 162, 243-252. doi:10.3354/meps162243Karakassis, I. (2000). Impact of cage farming of fish on the seabed in three Mediterranean coastal areas. ICES Journal of Marine Science, 57(5), 1462-1471. doi:10.1006/jmsc.2000.0925Basaran, A. K., Aksu, M., & Egemen, O. (2009). Impacts of the fish farms on the water column nutrient concentrations and accumulation of heavy metals in the sediments in the eastern Aegean Sea (Turkey). Environmental Monitoring and Assessment, 162(1-4), 439-451. doi:10.1007/s10661-009-0808-xLa Rosa, T., Mirto, S., Favaloro, E., Savona, B., Sarà, G., Danovaro, R., & Mazzola, A. (2002). Impact on the water column biogeochemistry of a Mediterranean mussel and fish farm. Water Research, 36(3), 713-721. doi:10.1016/s0043-1354(01)00274-3Maldonado, M., Carmona, M. C., Echeverría, Y., & Riesgo, A. (2005). The environmental impact of Mediterranean cage fish farms at semi-exposed locations: does it need a re-assessment? Helgoland Marine Research, 59(2), 121-135. doi:10.1007/s10152-004-0211-5Mantzavrakos, E., Kornaros, M., Lyberatos, G., & Kaspiris, P. (2007). Impacts of a marine fish farm in Argolikos Gulf (Greece) on the water column and the sediment. Desalination, 210(1-3), 110-124. doi:10.1016/j.desal.2006.05.037Martins, C. I. M., Galhardo, L., Noble, C., Damsgård, B., Spedicato, M. T., Zupa, W., … Kristiansen, T. (2011). Behavioural indicators of welfare in farmed fish. Fish Physiology and Biochemistry, 38(1), 17-41. doi:10.1007/s10695-011-9518-8Morata, T., Sospedra, J., Falco, S., & Rodilla, M. (2012). Exchange of nutrients and oxygen across the sediment–water interface below a Sparus aurata marine fish farm in the north-western Mediterranean Sea. Journal of Soils and Sediments, 12(10), 1623-1632. doi:10.1007/s11368-012-0581-2Murray L. Bulling M. Mayor D. Sanz-Lázaro C. Paton G. Killham K. Sosal M. 2008 Interactive effects of biodiversity, copper and a chemotherapeutant on marine benthic function Proceedings of the World Conference on Marine Biodiversity (MARBEF) Valencia, SpainNizzoli, D., Bartoli, M., & Viaroli, P. (2007). Oxygen and ammonium dynamics during a farming cycle of the bivalve Tapes philippinarum. Hydrobiologia, 587(1), 25-36. doi:10.1007/s10750-007-0683-9Olivos-Ortiz, A. (2002). Continental runoff of nutrients and their possible influence over stoichiometrical relations (DIN:P:Si) in the Northwest Mediterranean waters. Ciencias Marinas, 28(4), 393-406. doi:10.7773/cm.v28i4.235Olsen L.M. Holmer M. Olsen Y. 2008 Perspectives of nutrient emission from fish aquaculture in coastal waters. Literature review with evaluated state of knowledge 87Oppedal, F., Juell, J.-E., & Johansson, D. (2007). Thermo- and photoregulatory swimming behaviour of caged Atlantic salmon: Implications for photoperiod management and fish welfare. Aquaculture, 265(1-4), 70-81. doi:10.1016/j.aquaculture.2007.01.050Pinedo, S., García, M., Satta, M. P., Torres, M. de, & Ballesteros, E. (2007). Rocky-shore communities as indicators of water quality: A case study in the Northwestern Mediterranean. Marine Pollution Bulletin, 55(1-6), 126-135. doi:10.1016/j.marpolbul.2006.08.044Porrello, S., Tomassetti, P., Manzueto, L., Finoia, M. G., Persia, E., Mercatali, I., & Stipa, P. (2005). The influence of marine cages on the sediment chemistry in the Western Mediterranean Sea. Aquaculture, 249(1-4), 145-158. doi:10.1016/j.aquaculture.2005.02.042Rosenberg, R. (2001). 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Study of 16 Portuguese activated sludge systems based on filamentous bacteria populations and their relationships with environmental parameters

A survey in 16 activated sludge waste water treatment plants (WWTP) was conducted to contribute to the knowledge of the environmental parameters that determine the composition of the filamentous community. A total of 128 samples of mixed liquor from municipal WWTP were collected during 2 years, and 22 filamentous morphotypes were identified. The most frequent and abundant filamentous bacteria were, in both cases and by this order, type 0041/0675, type 0092, Microthrix parvicella and 1851, nocardioforms and Haliscomenobacter hydrossis. Concerning dominance, type 1851 was the most frequently dominant morphotype, followed by M. parvicella and types 0092 and 0041/0675. These were also, and by this order, the dominant morphotypes during bulking occurrences. Significant correlations were obtained between the abundance of filamentous bacteria and environmental parameters, but multivariate statistical analysis only confirmed the correlation between type 0092 and Sludge Volume Index (SVI), emphasizing the association of this filament with bulking. The discussion of the results in light of published works was complicated by the random use of terms such as frequency, abundance, and dominance with different and often unclear meanings. This reinforces the need of clarifying these terms when discussing the causes of filamentous overgrowth in WWTP.Portuguese Foundation for Science and Technology (FCT) and the European Community fund FEDER, through Program COMPETE, in the ambit of the Projects FCOMP-01-0124-FEDER-007025 (PTDC/AMB/68393/2006), PEst-OE/EQB/LA0023/2013, RECI/BBB-EBI/0179/2012 (FCOMP-01-0124-FEDER-027462), and the Project BBioEnv - Biotechnology and Bioengineering for a sustainable world,REF. NORTE-07-0124- FEDER-000048, co-funded by the Programa Operacional Regional do Norte (ON.2 – O Novo Norte), QREN, FEDER. PhD grant SFRH/BD/64848/200