Optimisation of Scenedesmus almeriensis production using pig slurry as the sole nutrient source

ABSTRACT Wheat and corn are important grains in the agricultural scenario of Brazil, and demand adequate supply of nutrients, particularly nitrogen, in crop succession. The use of pig slurry (PS) as a full and/or partial alternative to mineral fertilization in crop areas has been identified as an important alternative for the disposal of this waste. Therefore, the objective of this study was to evaluate the utilization of PS as fertilizer in wheat/corn succession under some plant parameters and grain yield. The experiment was conducted under field in randomized block design with four replications and five treatments, three with PS (40, 80, 160 m³ ha-1) and two controls (no fertilization and mineral NPK fertilization), which were applied manually in the soil shortly after sowing the crops. The application of PS proved to be a significant source of nutrients in wheat/corn succession. In comparison to NPK fertilization, this increase was only of 5.4% and 4.7% for wheat and corn, respectively. PS is an efficient alternative and it can be used as a source of these nutrients in wheat/corn succession, and the use of 80 m3ha-1 provides satisfactory results for all evaluated variables.

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A field treatment plant for pig slurry

Water Science & Technology ◽

10.2166/wst.1996.0266 ◽

1996 ◽

Vol 34 (11) ◽

pp. 87-92

Author(s):

José Martinez ◽

Xiaodi Hao

Keyword(s):

Carbon Source ◽

Lolium Perenne ◽

Treatment Effect ◽

Efficient Solution ◽

Treatment Plant ◽

Drainage Water ◽

Pig Slurry ◽

Total Recovery ◽

Animal Wastes ◽

Leachate Water

The SOLEPUR process for the treatment of pig slurry, based on the treatment effect of the soil, was developed in France to explore the notion that a simple biobarrier approach may be a potential efficient solution to the large accumulation of liquid animal wastes residues. The unit consists of (i) a managed field (3280 m2) which allows the total recovery of all the leachate water which percolates through growing ryegrass (Lolium perenne), to which the pig slurry is applied, (ii) a system of storage-pump-reactor for denitrification and (iii) a non-managed field for completing treatment. The process involves three operations: (1) overdosing the managed field with surplus slurry (about 1000 m3 pig slurry/ha.year applied from 1991 to 1994), (2) collecting and treating the nitrate-rich leachate and (3) irrigating the final treated water over other fields. This process decreased COD of pig slurry by 99.9 % and removed 99.9 % of phosphorus and approximately 80 % of nitrogen. The remaining nitrogen was oxidized in the soil into nitrate and leached out in the drainage water. The process of denitrification was selected to remove nitrate from the leachate and raw pig slurry was used as an external carbon source.

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Solid, slightly soluble phosphorus compounds as nutrient source in activated sludge treatment of forest industry wastewaters

Water Science & Technology ◽

10.2166/wst.1997.0500 ◽

1997 ◽

Vol 35 (2-3) ◽

pp. 131-138 ◽

Cited By ~ 1

Author(s):

Pirjo-Riitta Rantala ◽

Hannu Wirola

Keyword(s):

Activated Sludge ◽

The Other ◽

Phosphorus Compounds ◽

Forest Industry ◽

Phosphorus Concentration ◽

Nutrient Source ◽

Sludge Treatment ◽

Grain Sizes ◽

Soluble Phosphorus ◽

The Mean

The aim of the study was to determine if solid, slightly soluble compounds can be used as nutrient source in activated sludge treatment plants instead of liquid phosphoric acid. Four different solid materials were tested in lab-scale solubility tests to find compounds which are least soluble. Two materials were chosen for further studies: apatite and raw phosphate. The use of apatite and raw phosphate as nutrient source was studied in lab-scale activated sludge reactors along with a control reactor where phosphorus was added in liquid form. The phosphorus dosage, measured as elementary phosphorus, was the same for all three reactors. The reactors were fed with pre-clarified chemi-thermomechanical pulp mill (CTMP) wastewater. There were no significant differences in the reductions of organic matter between the three reactors. The mean effluent concentration of total phosphorus was 3 mg P/l in the control reactor and less than 1 mg P/1 in the other two reactors. The soluble phosphorus concentration was more than 2 mg P/l in the control reactor and less than 0.5 mg P/l in the other two. Apatite was an even better nutrient source than raw phosphate. Further lab-scale tests were conducted using two different grain sizes of apatite. No significant differences were found between the studied grain sizes (<0.074 mm and 0.074 mm-0.125 mm). Apatite was then used in full-scale at a CTMP-mill two different times. The experiments showed that the mean concentrations of phosphorus can be reduced radically by using apatite as a nutrient source instead of liquid phosphorus. Solid phosphorus compounds are a viable alternative to reduce the phosphorus load from forest industry wastewater treatment plants.

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Effects of Soil, Cover Crop, and Nutrient Source on Amounts and Forms of Phosphorus Movement Under Simulated Rainfall Conditions

Journal of Environmental Quality ◽

10.2134/jeq1978.00472425000700010010x ◽

1978 ◽

Vol 7 (1) ◽

pp. 50-54 ◽

Cited By ~ 16

Author(s):

G. Y. Reddy ◽

E. O. Mc Lean ◽

G. D. Hoyt ◽

T. J. Logan

Keyword(s):

Cover Crop ◽

Soil Cover ◽

Simulated Rainfall ◽

Nutrient Source

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Nitrogen fertilizer value of animal slurries with different proportions of liquid and solid fractions: A 3-year study under field conditions

The Journal of Agricultural Science ◽

10.1017/s0021859621000083 ◽

2021 ◽

pp. 1-11

Author(s):

Betina Nørgaard Pedersen ◽

Bent T. Christensen ◽

Luca Bechini ◽

Daniele Cavalli ◽

Jørgen Eriksen ◽

...

Keyword(s):

Solid Fraction ◽

Liquid Fraction ◽

N Fertilizer ◽

Organic N ◽

First Year ◽

Net N Mineralization ◽

Pig Slurry ◽

Total N ◽

Plant Availability ◽

Loamy Sand Soil

Abstract The plant availability of manure nitrogen (N) is influenced by manure composition in the year of application whereas some studies indicate that the legacy effect in following years is independent of the composition. The plant availability of N in pig and cattle slurries with variable contents of particulate matter was determined in a 3-year field study. We separated cattle and a pig slurry into liquid and solid fractions by centrifugation. Slurry mixtures with varying proportions of solid and liquid fraction were applied to a loamy sand soil at similar NH4+-N rates in the first year. Yields and N offtake of spring barley and undersown perennial ryegrass were compared to plots receiving mineral N fertilizer. The first year N fertilizer replacement value (NFRV) of total N in slurry mixtures decreased with increasing proportion of solid fraction. The second and third season NFRV averaged 6.5% and 3.8% of total N, respectively, for cattle slurries, and 18% and 7.5% for pig slurries and was not related to the proportion of solid fraction. The estimated net N mineralization of residual organic N increased nearly linearly with growing degree days (GDD) with a rate of 0.0058%/GDD for cattle and 0.0116%/GDD for pig slurries at 2000–5000 GDD after application. In conclusion NFRV of slurry decreased with increasing proportion of solid fraction in the first year. In the second year, NFRV of pig slurry N was significantly higher than that of cattle slurry N and unaffected by proportion between solid and liquid fraction.

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Mechanism of NanR gene repression and allosteric induction of bacterial sialic acid metabolism

Nature Communications ◽

10.1038/s41467-021-22253-6 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Christopher R. Horne ◽

Hariprasad Venugopal ◽

Santosh Panjikar ◽

David M. Wood ◽

Amy Henrickson ◽

...

Keyword(s):

Sialic Acid ◽

Dna Binding ◽

Protein Interactions ◽

Acid Metabolism ◽

Environmental Changes ◽

Dna Interaction ◽

Protein Protein Interactions ◽

Nutrient Source ◽

Cryo Electron Microscopy ◽

Close Proximity

AbstractBacteria respond to environmental changes by inducing transcription of some genes and repressing others. Sialic acids, which coat human cell surfaces, are a nutrient source for pathogenic and commensal bacteria. The Escherichia coli GntR-type transcriptional repressor, NanR, regulates sialic acid metabolism, but the mechanism is unclear. Here, we demonstrate that three NanR dimers bind a (GGTATA)3-repeat operator cooperatively and with high affinity. Single-particle cryo-electron microscopy structures reveal the DNA-binding domain is reorganized to engage DNA, while three dimers assemble in close proximity across the (GGTATA)3-repeat operator. Such an interaction allows cooperative protein-protein interactions between NanR dimers via their N-terminal extensions. The effector, N-acetylneuraminate, binds NanR and attenuates the NanR-DNA interaction. The crystal structure of NanR in complex with N-acetylneuraminate reveals a domain rearrangement upon N-acetylneuraminate binding to lock NanR in a conformation that weakens DNA binding. Our data provide a molecular basis for the regulation of bacterial sialic acid metabolism.

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Innovations in anaerobic digestion: a model-based study

Biotechnology for Biofuels ◽

10.1186/s13068-020-01864-z ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Karol Postawa ◽

Jerzy Szczygieł ◽

Marek Kułażyński

Keyword(s):

Mathematical Model ◽

Anaerobic Digestion ◽

Production Efficiency ◽

Biogas Production ◽

Biogas Plant ◽

Methane Content ◽

Pig Manure ◽

Pig Slurry ◽

Production Chain ◽

The Impact

Abstract Background Increasing the efficiency of the biogas production process is possible by modifying the technological installations of the biogas plant. In this study, specific solutions based on a mathematical model that lead to favorable results were proposed. Three configurations were considered: classical anaerobic digestion (AD) and its two modifications, two-phase AD (TPAD) and autogenerative high-pressure digestion (AHPD). The model has been validated based on measurements from a biogas plant located in Poland. Afterward, the TPAD and AHPD concepts were numerically tested for the same volume and feeding conditions. Results The TPAD system increased the overall biogas production from 9.06 to 9.59%, depending on the feedstock composition, while the content of methane was slightly lower in the whole production chain. On the other hand, the AHPD provided the best purity of the produced fuel, in which a methane content value of 82.13% was reached. At the same time, the overpressure leads to a decrease of around 7.5% in the volumetric production efficiency. The study indicated that the dilution of maize silage with pig manure, instead of water, can have significant benefits in the selected configurations. The content of pig slurry strengthens the impact of the selected process modifications—in the first case, by increasing the production efficiency, and in the second, by improving the methane content in the biogas. Conclusions The proposed mathematical model of the AD process proved to be a valuable tool for the description and design of biogas plant. The analysis shows that the overall impact of the presented process modifications is mutually opposite. The feedstock composition has a moderate and unsteady impact on the production profile, in the tested modifications. The dilution with pig manure, instead of water, leads to a slightly better efficiency in the classical configuration. For the TPAD process, the trend is very similar, but the AHPD biogas plant indicates a reverse tendency. Overall, the recommendation from this article is to use the AHPD concept if the composition of the biogas is the most important. In the case in which the performance is the most important factor, it is favorable to use the TPAD configuration.

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Winter Wheat Straw Decomposition under Different Nitrogen Fertilizers

Agriculture ◽

10.3390/agriculture11020083 ◽

2021 ◽

Vol 11 (2) ◽

pp. 83

Author(s):

Gabriela Mühlbachová ◽

Pavel Růžek ◽

Helena Kusá ◽

Radek Vavera ◽

Martin Káš

Keyword(s):

Winter Wheat ◽

Wheat Straw ◽

Soil Surface ◽

Weather Conditions ◽

Mineral Nitrogen ◽

Nitrogen Fertilizers ◽

Pig Slurry ◽

Straw Decomposition ◽

Rainy Weather ◽

N Fertilisers

The climate changes and increased drought frequency still more frequent in recent periods bring challenges to management with wheat straw remaining in the field after harvest and to its decomposition. The field experiment carried out in 2017–2019 in the Czech Republic aimed to evaluate winter wheat straw decomposition under different organic and mineral nitrogen fertilizing (urea, pig slurry and digestate with and without inhibitors of nitrification (IN)). Treatment Straw 1 with fertilizers was incorporated in soil each year the first day of experiment. The Straw 2 was placed on soil surface at the same day as Straw 1 and incorporated together with fertilizers after 3 weeks. The Straw 1 decomposition in N treatments varied between 25.8–40.1% and in controls between 21.5–33.1% in 2017–2019. The Straw 2 decomposition varied between 26.3–51.3% in N treatments and in controls between 22.4–40.6%. Higher straw decomposition in 2019 was related to more rainy weather. The drought observed mainly in 2018 led to the decrease of straw decomposition and to the highest contents of residual mineral nitrogen in soils. The limited efficiency of N fertilisers on straw decomposition under drought showed a necessity of revision of current strategy of N treatments and reduction of N doses adequately according the actual weather conditions.

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Evaluation of Tomato-Based Packing Material for Retention of Ammonia, Nitrous Oxide, Carbon Dioxide and Methane in Gas Phase Biofilters: A Laboratory Study

Agronomy ◽

10.3390/agronomy11020360 ◽

2021 ◽

Vol 11 (2) ◽

pp. 360

Author(s):

José L. S. Pereira ◽

Adelaide Perdigão ◽

Francisco Marques ◽

Catarina Coelho ◽

Mariana Mota ◽

...

Keyword(s):

Oxalic Acid ◽

Laboratory Study ◽

Packing Material ◽

Control Treatment ◽

Airflow Rate ◽

Pig Slurry ◽

Air Pollution Control ◽

Gaseous Emissions ◽

Packing Materials ◽

Tomato Waste

Biofilters are an effective air pollution control technology to break down gaseous contaminants and produce innocuous end products. This laboratory study aimed to evaluate a biofilter media, mainly composed by tomato waste, as packing material to reduce NH3, N2O, CO2 and CH4 losses from stored pig slurry. Three mixtures of packing materials, with and without oxalic acid, were arranged in treatments, namely: mixture of tomato waste, pine bark and agricultural compost; mixture of tomato waste and rice husk; tomato waste only. A control treatment (no biofilter) was also included. The experiments were conducted using a system of laboratory scale biofilters connected to jars filled with pig slurry and under a constant airflow rate. The gas concentrations were measured for 14 days and the physicochemical of the packing materials were assessed. Results showed that biofilter media mixtures had a potential for NH3 retention ranging from 51 to 77% and the addition of oxalic acid to these biofilters increased NH3 retention to 72–79%. Additionally, the biofilter media mixtures with and without oxalic acid showed a potential retention for CH4 (29–69%) but not for N2O, yet with no impact on the global warming potential. It can be concluded that tomato based biofilters had the potential to reduce gaseous emissions from slurry.

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