scholarly journals The use of co-digested solid fraction as feedstock for biogas plants

2013 ◽  
Vol 44 (2s) ◽  
Author(s):  
E. Dinuccio ◽  
F. Gioelli ◽  
D. Cuk ◽  
L. Rollè ◽  
P. Balsari
Keyword(s):  
Solid Fraction ◽  
Farmyard Manure ◽  
Daily Basis ◽  
Pig Slurry ◽  
Stirred Tank Reactors ◽  
Time Period ◽  
Study Results ◽  
Biogas Plants ◽  
Set Up ◽  
Sorghum Silage

A comparative study was set up in order to assess the technical feasibility of the long-term reuse of the mechanically separated co-digested solid fraction as a feedstock for anaerobic digestion plants (ADP). The biogas yields of two feedstock mixtures (A and B) were assessed in mesophilic conditions (40 °C ± 2 °C) using 8 lab-scale continuous stirred-tank reactors (CSRT). Feedstock mixture A (control) consisted of pig slurry (70%), farmyard manure (4%), sorghum silage (12%) and maize silage (14%). Feedstock mixture B was the same as the control plus the solid fraction derived from the mechanical separation of the output raw co-digestate collected on daily basis from the reactors. All reactors were fed simultaneously, three times a week, over a period of nine month. According to the study results, the reuse of the co-digested solid fraction as feedstock for ADP could increase the methane yield by approximately 4%. However, ADP efficiency evaluation (e.g., daily yield of methane per m3 of digester) suggest to limit this practice to a maximum time period of 120 days.

scholarly journals The use of co-digested solid fraction as feedstock for biogas plants

2014 ◽  
Vol 44 (4) ◽  
pp. 153
Author(s):  
Elio Dinuccio ◽  
Fabrizio Gioelli ◽  
Dalibor Cuk ◽  
Luca Rollè ◽  
Paolo Balsari
Keyword(s):  
Solid Fraction ◽  
Farmyard Manure ◽  
Pig Slurry ◽  
Time Period ◽  
Study Results ◽  
Biogas Plants ◽  
Mechanical Separation ◽  
Set Up ◽  
Sorghum Silage

A comparative study was set up in order to assess the technical feasibility of the long-term reuse of the mechanically separated co-digested solid fraction as a feedstock for anaerobic digestion plants (ADP). The biogas yields of two feedstock mixtures (A and B) were assessed in mesophilic conditions (40°C±2°C) using 6 lab-scale continuous stirredtank reactors. Feedstock mixture A (control) consisted of pig slurry (70%), farmyard manure (4%), sorghum silage (12%) and maize silage (14%). Feedstock mixture B was the same as the control plus the solid fraction derived from the mechanical separation of the output raw codigestate collected from the reactors. All reactors were fed simultaneously, three times a week, over a period of nine month. According to the study results, the reuse of the co-digested solid fraction as feedstock for ADP could increase the methane yield by approximately 4%. However, ADP efficiency evaluation (<em>e.g.</em>, daily yield of methane per m<sup>3</sup> of digester) suggests limiting this practice to a maximum time period of 120 days.

scholarly journals Fertilizer value and greenhouse gas emissions from solid fraction pig slurry compost pellets

2017 ◽  
Vol 155 (10) ◽  
pp. 1646-1658 ◽  
Author(s):  
N. PAMPURO ◽  
C. BERTORA ◽  
D. SACCO ◽  
E. DINUCCIO ◽  
C. GRIGNANI ◽  
...  
Keyword(s):  
Greenhouse Gas ◽  
Solid Fraction ◽  
Ghg Emissions ◽  
Small Diameter ◽  
Wood Chip ◽  
Bulking Agent ◽  
Control Treatment ◽  
Pig Slurry ◽  
Fertilizer Value ◽  
Study Results

SUMMARYConversion of pig slurry to pellets is a desirable fertilizer option for farmers who want to mitigate environmental pollution from slurry accumulation. The goals of the current investigation were to determine the fertilizer properties of pig slurry solid fraction (SF) pellets and to assess its potential to enhance soil properties in order to reduce ammonia (NH3) volatilization and greenhouse gas (GHG) emissions. Various parameters influence SF-based pellet fertilizer effectiveness: bulking agent use during composting, pellet diameter sizing and soil application type (superficially or incorporated into the soil). Two composts from the same pig slurry SF obtained from a screw press separator were prepared: pig SF compost without a bulking agent (SSFC) and pig SF compost with wood chips as the bulking agent (wood chip compost (WCC)). For each compost type, pellets of two different diameters (6 and 8 mm) were produced. A mesocosm experiment, conducted with maize plants, was used to test the fertilizer value of the considered pellets. In total, three compost fertilizers – SSFC, WCC and nitrogen: phosphorus: potassium mineral fertilizer 15 : 15 : 15, plus one unfertilized control treatment – were applied at the same N rate (equivalent to 200 kg/ha) using two different methods (surface and soil incorporation). After 65 days, above-ground biomass, roots and soil samples were collected and analysed. Subsequently, a second mesocosm study was undertaken to measure NH3and GHG emissions released from pellet fertilization. Ammonia volatilization was determined immediately after pellet application, while carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) emissions were monitored for 57 days. Study results indicated that both pellet types were effective slow-release fertilizers for maize. Additionally, three actions seemed to make the nutrients contained in pig SF compost pellets more available to plants: addition of a bulking agent before composting, use of small diameter pellets and soil incorporation of the fertilizer.

scholarly journals Characteristics of the Baseline Climate of the Cotnari (Romania) Wine Growing Region

2015 ◽  
Vol 47 (4) ◽  
pp. 99-111 ◽  
Author(s):  
L.M. Irimi ◽  
Cr.V. Patriche ◽  
H. Quénol ◽  
O. Planchon ◽  
L. Sfâcă
Keyword(s):  
Global Radiation ◽  
Growing Season ◽  
Wine Grape ◽  
Climate Data ◽  
Time Period ◽  
Study Results ◽  
Climate Suitability ◽  
Set Up ◽  
Baseline Climate ◽  
Growing Region

Abstract The paper presents the baseline climate of the Cotnari wine growing region, the climate under whose influence were set up the wine grape varieties, wine types and grapevine training systems of this vineyard. It is also presented the baseline climate suitability for wine grape growing and its spatial variation in the vineyard area. The study is based on the climate data for the 1961 to 1980 time period, previous to the beginning of the climate warming and, therefore, considered to be representative for the baseline climate time period. According to study results, the baseline climate of the Cotnari wine growing region was cool, with annual average temperatures by 8.5...,10.0°C, with a sum of the effective temperatures by 1081...,1382°C, with freezing phenomena at the beginning and towards the end of the growing season, and with very cool nights during the month of September (CI+2). Elements that generate the baseline climate suitability for wine grape growing were: high average temperatures for the month of July (19...21.1°C), long growing season up to 190 days, and high values for the global radiation, up to 93 kcal/cm2/April 1st - September 30th on the sunny slopes within the vineyard area. According to the multicriteria evaluation of the suitability for wine grape growing, 87.9% (1792 ha) of the vineyard surface was characterized by a baseline climate suitable for white quality wines and 11.9% (241.0 ha) by a baseline climate suitable for white table wines, sparkling wines and wines for distillates.

scholarly journals Agent-Based Coordinated Control of Power Electronic Converters in a Microgrid

Electronics ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1031
Author(s):  
Maryam Nasri ◽  
Herbert L. Ginn ◽  
Mehrdad Moallem
Keyword(s):  
Hash Table ◽  
Power Sharing ◽  
Distributed Hash Table ◽  
Power Electronic ◽  
Power Electronic Converters ◽  
Agent Based ◽  
Development Framework ◽  
Study Results ◽  
Set Up ◽  
Microgrid Control

This paper presents the implementation of an agent-based architecture suitable for the coordination of power electronic converters in stand-alone microgrids. To this end, a publish-subscribe agent architecture was utilized as a distributed microgrid control platform. Over a distributed hash table (DHT) searching overlay, the publish-subscribe architecture was identified based on a numerical analysis as a scalable agent-based technology for the distributed real-time coordination of power converters in microgrids. The developed framework was set up to deploy power-sharing distributed optimization algorithms while keeping a deterministic time period of a few tens of milliseconds for a system with tens of converters and when multiple events might happen concurrently. Several agents participate in supervisory control to regulate optimum power-sharing for the converters. To test the design, a notional shipboard system, including several converters, was used as a case study. Results of implementing the agent-based publish-subscribe control system using the Java Agent Development Framework (JADE) are presented.

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

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.

scholarly journals Prediction of Pest Insect Appearance Using Sensors and Machine Learning

Sensors ◽  
2021 ◽  
Vol 21 (14) ◽  
pp. 4846
Author(s):  
Dušan Marković ◽  
Dejan Vujičić ◽  
Snežana Tanasković ◽  
Borislav Đorđević ◽  
Siniša Ranđić ◽  
...  
Keyword(s):  
Machine Learning ◽  
Relative Humidity ◽  
Weather Conditions ◽  
Daily Basis ◽  
Machine Learning Algorithms ◽  
Lower Percentage ◽  
Timely Manner ◽  
Proposed Model ◽  
Set Up ◽  
Accuracy Of Prediction

The appearance of pest insects can lead to a loss in yield if farmers do not respond in a timely manner to suppress their spread. Occurrences and numbers of insects can be monitored through insect traps, which include their permanent touring and checking of their condition. Another more efficient way is to set up sensor devices with a camera at the traps that will photograph the traps and forward the images to the Internet, where the pest insect’s appearance will be predicted by image analysis. Weather conditions, temperature and relative humidity are the parameters that affect the appearance of some pests, such as Helicoverpa armigera. This paper presents a model of machine learning that can predict the appearance of insects during a season on a daily basis, taking into account the air temperature and relative humidity. Several machine learning algorithms for classification were applied and their accuracy for the prediction of insect occurrence was presented (up to 76.5%). Since the data used for testing were given in chronological order according to the days when the measurement was performed, the existing model was expanded to take into account the periods of three and five days. The extended method showed better accuracy of prediction and a lower percentage of false detections. In the case of a period of five days, the accuracy of the affected detections was 86.3%, while the percentage of false detections was 11%. The proposed model of machine learning can help farmers to detect the occurrence of pests and save the time and resources needed to check the fields.

scholarly journals Preferences for Updates on General Research Results: A Survey of Participants in Genomic Research from Two Institutions

2021 ◽  
Vol 11 (5) ◽  
pp. 399
Author(s):  
Casey Overby Taylor ◽  
Natalie Flaks Manov ◽  
Katherine D. Crew ◽  
Chunhua Weng ◽  
John J. Connolly ◽  
...  
Keyword(s):  
Research Result ◽  
Hierarchical Cluster ◽  
Genomic Research ◽  
Cross Sectional Survey ◽  
Cross Sectional ◽  
Four Dimensions ◽  
Research Participants ◽  
Research Activities ◽  
Study Results ◽  
Set Up

There is a need for multimodal strategies to keep research participants informed about study results. Our aim was to characterize preferences of genomic research participants from two institutions along four dimensions of general research result updates: content, timing, mechanism, and frequency. Methods: We conducted a web-based cross-sectional survey that was administered from 25 June 2018 to 5 December 2018. Results: 397 participants completed the survey, most of whom (96%) expressed a desire to receive research updates. Preferences with high endorsement included: update content (brief descriptions of major findings, descriptions of purpose and goals, and educational material); update timing (when the research is completed, when findings are reviewed, when findings are published, and when the study status changes); update mechanism (email with updates, and email newsletter); and update frequency (every three months). Hierarchical cluster analyses based on the four update preferences identified four profiles of participants with similar preference patterns. Very few participants in the largest profile were comfortable with budgeting less money for research activities so that researchers have money to set up services to send research result updates to study participants. Conclusion: Future studies may benefit from exploring preferences for research result updates, as we have in our study. In addition, this work provides evidence of a need for funders to incentivize researchers to communicate results to participants.

scholarly journals Condensation/immersion mode ice-nucleating particles in a boreal environment

2020 ◽  
Vol 20 (11) ◽  
pp. 6687-6706
Author(s):  
Mikhail Paramonov ◽  
Saskia Drossaart van Dusseldorp ◽  
Ellen Gute ◽  
Jonathan P. D. Abbatt ◽  
Paavo Heikkilä ◽  
...  
Keyword(s):  
Field Campaign ◽  
Particle Species ◽  
Entire Field ◽  
Time Period ◽  
Regional Sources ◽  
Range Transport ◽  
Thermodynamic Conditions ◽  
Set Up ◽  
Boreal Environment ◽  
Measurement Location

Abstract. Ice-nucleating particle (INP) measurements were performed in the boreal environment of southern Finland at the Station for Measuring Ecosystem–Atmosphere Relations (SMEAR II) in the winter–spring of 2018. Measurements with the Portable Ice Nucleation Chamber (PINC) were conducted at 242 K and 105 % relative humidity with respect to water. The median INP number concentration [INP] during a 6-week measurement period was 13 L−1. The [INP] spanned 3 orders of magnitude and showed a general increase from mid-February until early April. No single dominant local or regional sources of INPs in the boreal environment of southern Finland could be identified. Rather, it is hypothesised that the INPs detected at SMEAR II are a result of long-range transport and dilution of INPs sourced far from the measurement site. Despite high variability, the measured [INP] values fall within the range expected for the [INP] measured elsewhere under similar thermodynamic conditions. The [INP] did not correlate with any of the examined parameters during the entire field campaign, indicating that no one single parameter can be used to predict the [INP] at the measurement location during the examined time period. The absence of a correlation across the entire field campaign also suggests that a variety of particles act as INPs at different times, although it was indirectly determined that ambient INPs are most likely within the size range of 0.1–0.5 µm in diameter on average. On shorter timescales, several particle species correlated well with the [INP]. Depending on the meteorological conditions, black carbon (BC), supermicron biological particles and sub-0.1 µm particles, most likely nanoscale biological fragments such as ice-nucleating macromolecules (INMs), correlated with the INP signal. However, an increase in the concentration of any of these particle species may not necessarily lead to the increase in the [INP]; the reasons for this remain unknown. Limitations of the instrumental set-up and the necessity for future field INP studies are addressed.

scholarly journals Energy and pressure requirements for compression of swine solid fraction compost

2013 ◽  
Vol 44 (2s) ◽  
Author(s):  
Niccolò Pampuro ◽  
Alessio Facello ◽  
Eugenio Cavallo
Keyword(s):  
Solid Fraction ◽  
Liquid Fraction ◽  
Value Added ◽  
Pig Slurry ◽  
Application Time ◽  
Soil Fertilization ◽  
Pressure Application ◽  
Potential Risks ◽  
Solid Liquid ◽  
Solid Liquid Separation

The excessive amount of pig slurry spread on soil has contributed to nitrate water pollution both in surface and in ground waters, especially in areas classified as vulnerable zones to nitrate in accordance with European Regulation (91/676/CEE). Several techniques have been developed to manage livestock slurries as cheaply and conveniently as possible and to reduce potential risks of environmental pollution. Among these techniques, solid-liquid separation of slurry is a common practice in Italy. The liquid fraction can be used for irrigation and the solid fraction, after aerobic stabilization, produces an organic compost rich in humic substances. However, compost derived from swine solid fraction is a low density material (bulk density less than 500 kg􀀀m–3). This makes it costly to transport composted swine solid fraction from production sites to areas where it could be effectively utilized for value-added applications such as in soil fertilization. Densification is one possible way to enhance the storage and transportation of the compost. This study therefore investigates the effect of pressure (20- 110 MPa) and pressure application time (5-120 s) on the compaction characteristics of compost derived from swine solid fraction. Two different types of material have been used: composted swine solid fraction derived from mechanical separation and compost obtained by mixing the first material with wood chips. Results obtained showed that both the pressure applied and the pressure application time significantly affect the density of the compacted samples; while the specific compression energy is significantly affected only by the pressure. Best predictor equations were developed to predict compact density and the specific compression energy required by the densification process. The specific compression energy values based on the results from this study (6-32 kJ􀀀kg–1) were significantly lower than the specific energy required to manufacture pellets from biomass feedstock (typically 19-90 kJ􀀀kg–1).

Sign in / Sign up

Export Citation Format

Share Document