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Sven G Sommer - One of the best experts on this subject based on the ideXlab platform.
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a whole farm assessment of the efficacy of Slurry acidification in reducing ammonia emissions
European Journal of Agronomy, 2008Co-Authors: Peter Kai, P Pedersen, J E Jensen, Martin N Hansen, Sven G SommerAbstract:Abstract Livestock Slurry in animal houses, in manure stores and applied on fields is in Denmark the most important source of ammonia (NH 3 ) in the atmosphere. The emitted NH 3 is a source of NH 3 and ammonium (NH 4 + ) deposition, which causes eutrophication of N-deficient ecosystems and may form NH 4 + -based particles in the air, which are a risk to health. This study examines the reductions in NH 3 emissions from pig houses, manure stores and manure applied in the field achieved by acidifying the Slurry in-house. Sulphuric acid was used to acidify pig Slurry to pH 3 emission from pig houses by 70% compared with standard techniques. Acidification reduced NH 3 emission from stored Slurry to less than 10% of the emission from untreated Slurry, and the NH 3 emission from applied Slurry was reduced by 67%. The mineral fertilizer equivalent (MFE) of acidified Slurry was 43% higher compared with the MFE of untreated Slurry when applied to the soil. The odour emission from the Slurry was not affected significantly by the treatment. The Slurry acidification system is approved Best Available Technology (BAT) in Denmark.
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methane and carbon dioxide emissions and nitrogen turnover during liquid manure storage
Nutrient Cycling in Agroecosystems, 2007Co-Authors: Sven G Sommer, Peter Sorensen, Soren O Petersen, Hanne Poulsen, Henrik Bjarne MollerAbstract:Animal Slurry stored in-house and outside is a significant source of atmospheric methane (CH4). The CH4 source strength of stored Slurry is greatly affected by temperature. To improve emission calculations on a global scale there is a need for knowledge about the relationship between production of CH4 in Slurry and temperature. In this study, the filling of Slurry channels was reproduced in the laboratory by gradually filling 1 m-high PVC vessels during 9 days followed by incubation for 100–200 days. A preliminary test showed that little CH4 was produced from animal Slurry during 10 days of incubation at 20°C, if no inoculum (Slurry incubated anaerobically at the test temperature for 1.5–2 months) was present. However, the addition of 7.6% inoculum supported an immediate production of CH4. Vessels amended with inoculum and gradually filled with cattle or pig Slurry were then incubated at 10, 15 and 20°C. Methane production from stored pig and cattle Slurry was not significant at temperatures below 15°C, where CO2 was the main product of decomposition processes. In contrast, the anaerobic production of CH4 was high and significant relative to the production of CO2 at 20°C. Peak emissions of CH4 averaging 0.012 and 0.02 g C h−1 kg−1 volatile solids (VS) were reached within about 10 days at 10 and 15°C, respectively. At 20°C, the emission of CH4 from pig Slurry was about 0.01 g C h−1 kg−1 for 10 days, and thereafter emissions increased to about 0.10 g C h−1 kg−1 VS. For cattle Slurry a peak emission of 0.08 g C h−1 kg−1 VS was measured after 180 days. Degradation of organic nitrogen (N) in cattle Slurry was related to the reduction of organic material as reflected in CO2 and CH4 emission. The mineralization of organic N during storage represented 10–80% of organic N in cattle Slurry, and 40–80% of the organic N in pig Slurry.
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ammonia volatilization from farm tanks containing anaerobically digested animal Slurry
Atmospheric Environment, 1997Co-Authors: Sven G SommerAbstract:Ammonia (NH3) volatilization from three full-scale tanks containing anaerobically digested animal Slurry from one biogas plant was determined with a meteorological mass balance technique. No surface crust developed on the Slurry. This provided an ideal system for analysing loss patterns from slurries without cover and to study the effect of a cover of straw and air-filled clay granules. Ammonia volatilization from uncovered Slurry ranged from zero at subzero temperatures to 30 g N m−2 d−1 during summer. The high volatilization rate was attributed to a lack of surface cover, high Slurry pH and high TAN (NH3 + NH4+) concentration. Ammonia volatilization from the covered Slurry was insignificant. From the uncovered Slurry the annual loss of NH3 was 3.3 kg N m−2 There was a significant effect of incident global radiation (ICR), air temperature at 20 cm (T_20) and rain on NH3 volatilization from the uncovered Slurry. The straw covered Slurry was significantly affected by T_20.
Peter Sorensen - One of the best experts on this subject based on the ideXlab platform.
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effects of Slurry acidification with sulphuric acid combined with aeration on the turnover and plant availability of nitrogen
Agriculture Ecosystems & Environment, 2009Co-Authors: Peter Sorensen, Jorgen EriksenAbstract:Abstract Ammonia (NH 3 ) losses from animal houses, Slurry storage and Slurry application can be significantly reduced by acidifying the Slurry in livestock houses. The acidification may potentially influence organic matter turnover during Slurry storage and therefore also the following release of inorganic nitrogen (N) after application to soil. We studied the effects of pig and cattle Slurry acidification with sulphuric acid on (1) N release in a loamy sand soil and (2) the N fertilizer replacement values after Slurry application to spring barley ( Hordeum vulgare L.) by incorporation and to winter wheat ( Triticum aestivum L.) by surface application. Pig and cattle slurries were acidified to pH 5.5 before storage but pH increased to above 6 at application in the field. The composition of Slurry after storage indicated that the organic matter turnover during storage is inhibited by acidification, probably due to the presence of acetate in combination with low pH. The acidified Slurry contained more butyric acid than the untreated Slurry. However, there was no clear effect of acidification on the subsequent mineral N release in soil. Effects of aeration of the acidified Slurry were also studied, but 4 days’ aeration had no detectable effects on Slurry composition and N availability. Slurry acidification had no detectable effect on the mineral N fertilizer equivalence (MFE) when Slurry was incorporated before sowing a barley crop, whereas after surface-banding the MFE of cattle Slurry N increased from 39 to 63% and of pig Slurry N from 74 to 101% due to the acidification. After acidification, the MFE of Slurry was similar in the two crops, indicating that NH 3 volatilisation from acidified cattle and pig Slurry was low both after incorporation and after surface application.
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methane and carbon dioxide emissions and nitrogen turnover during liquid manure storage
Nutrient Cycling in Agroecosystems, 2007Co-Authors: Sven G Sommer, Peter Sorensen, Soren O Petersen, Hanne Poulsen, Henrik Bjarne MollerAbstract:Animal Slurry stored in-house and outside is a significant source of atmospheric methane (CH4). The CH4 source strength of stored Slurry is greatly affected by temperature. To improve emission calculations on a global scale there is a need for knowledge about the relationship between production of CH4 in Slurry and temperature. In this study, the filling of Slurry channels was reproduced in the laboratory by gradually filling 1 m-high PVC vessels during 9 days followed by incubation for 100–200 days. A preliminary test showed that little CH4 was produced from animal Slurry during 10 days of incubation at 20°C, if no inoculum (Slurry incubated anaerobically at the test temperature for 1.5–2 months) was present. However, the addition of 7.6% inoculum supported an immediate production of CH4. Vessels amended with inoculum and gradually filled with cattle or pig Slurry were then incubated at 10, 15 and 20°C. Methane production from stored pig and cattle Slurry was not significant at temperatures below 15°C, where CO2 was the main product of decomposition processes. In contrast, the anaerobic production of CH4 was high and significant relative to the production of CO2 at 20°C. Peak emissions of CH4 averaging 0.012 and 0.02 g C h−1 kg−1 volatile solids (VS) were reached within about 10 days at 10 and 15°C, respectively. At 20°C, the emission of CH4 from pig Slurry was about 0.01 g C h−1 kg−1 for 10 days, and thereafter emissions increased to about 0.10 g C h−1 kg−1 VS. For cattle Slurry a peak emission of 0.08 g C h−1 kg−1 VS was measured after 180 days. Degradation of organic nitrogen (N) in cattle Slurry was related to the reduction of organic material as reflected in CO2 and CH4 emission. The mineralization of organic N during storage represented 10–80% of organic N in cattle Slurry, and 40–80% of the organic N in pig Slurry.
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Remineralisation and residual effects of N after application of pig Slurry to soil
European Journal of Agronomy, 2002Co-Authors: Peter Sorensen, Maurice AmatoAbstract:A significant proportion of ammonium-N in pig Slurry is immobilised during microbial decomposition of organic matter in the Slurry soon after application to soil. Immobilisation and remineralisation of N influence the fertiliser value of Slurry N and the amount of organic N that is retained in soil. We studied the immobilisation and remineralisation of 15N-labelled pig Slurry NH4-N after application in the field through three growing seasons under temperate conditions. Effects of Slurry distribution (incorporation, injection, surface-banding), soil type and soil tillage on the plant utilisation of labelled NH4-N from Slurry were studied and compared to the utilisation of 15N-labelled mineral fertiliser. Residual N effects of the pig Slurry in the 2 years following the application were also measured by comparing plant N uptake in plots that initially received Slurry or only mineral fertiliser N. The initial immobilisation of Slurry N was significantly influenced by the Slurry distribution in soil. More N was immobilised when the Slurry was mixed with soil, but the remineralisation rate (% crop removal of residual 15N) in the following years was not significantly influenced by the initial Slurry distribution. Surface-banding of Slurry resulted in significant volatilisation losses and less residual 15N retained in soil. After 2.5 years the recovery of labelled N in soil was 41-45% for Slurry mixed with soils, 38-43% for injected Slurry, 22-34% for surface-banded Slurry and 25% for mineral fertiliser N. Thus, more N was immobilised after Slurry incorporation than after mineral fertiliser application, but the remineralisation rate (% crop removal of residual 15N) in the following years was nearly similar for fertiliser-and Slurry-derived N. The remineralisation rate was lowest in the soil containing the most clay, but was not significantly influenced by soil tillage. It is concluded that a significant part of the organic N retained in soil after pig Slurry application is derived from the immobilised ammonium-N and will be slowly released over many years. The contribution of immobilised N to the residual N effect of pig Slurry is relatively low, but consistent in the first years after Slurry application. © 2002 Elsevier Science B.V. All rights reserved.
Anders Dalsgaard - One of the best experts on this subject based on the ideXlab platform.
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Viability of Ascaris suum eggs in stored raw and separated liquid Slurry.
Parasitology, 2012Co-Authors: Kiran Kumar Katakam, Allan Roepstorff, Olga Popovic, Niels C. Kyvsgaard, Stig Milan Thamsborg, Anders DalsgaardAbstract:Separation of pig Slurry into solid and liquid fractions is gaining importance as a way to manage increasing volumes of Slurry. In contrast to solid manure and Slurry, little is known about pathogen survival in separated liquid Slurry. The viability of Ascaris suum eggs, a conservative indicator of fecal pollution, and its association with ammonia was investigated in separated liquid Slurry in comparison with raw Slurry. For this purpose nylon bags with 6000 eggs each were placed in 1 litre bottles containing one of the two fractions for 308 days at 5 °C or 25 °C. Initial analysis of helminth eggs in the separated liquid Slurry revealed 47 Ascaris eggs per gramme. At 25 °C, egg viability declined to zero with a similar trend in both raw Slurry and the separated liquid Slurry by day 308, a time when at 5 °C 88% and 42% of the eggs were still viable in separated liquid Slurry and raw Slurry, respectively. The poorer survival at 25 °C was correlated with high ammonia contents in the range of 7.9-22.4 mM in raw Slurry and 7.3-23.2 mM in liquid Slurry compared to 3.2-9.5 mM in raw Slurry and 2.6-9.5 mM in liquid Slurry stored at 5 °C. The study demonstrates that at 5 °C, A. suum eggs have a higher viability in separated liquid Slurry as compared to raw Slurry. The hygiene aspect of this needs to be further investigated when separated liquid Slurry is used to fertilize pastures or crops.
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transport of cryptosporidium parvum oocysts in soil columns following applications of raw and separated liquid slurries
Applied and Environmental Microbiology, 2012Co-Authors: Heidi Huus Petersen, Heidi L Enemark, Annette Olsen, M Mostofa G Amin, Anders DalsgaardAbstract:The potential for the transport of viable Cryptosporidium parvum oocysts through soil to land drains and groundwater was studied using simulated rainfall and intact soil columns which were applied raw Slurry or separated liquid Slurry. Following irrigation and weekly samplings over a 4-week period, C. parvum oocysts were detected from all soil columns regardless of Slurry type and application method, although recovery rates were low (<1%). Soil columns with injected liquid Slurry leached 73 and 90% more oocysts compared to columns with injected and surface-applied raw slurries, respectively. Among leachate samples containing oocysts, 44/72 samples yielded viable oocysts as determined by a dye permeability assay (DAPI [4',6'-diamidino-2-phenylindole]/propidium iodide) with the majority (41%) of viable oocysts found in leachate from soil columns with added liquid Slurry. The number of viable oocysts was positively correlated (r = 0.63) with the total number of oocysts found. Destructively sampling of the soil columns showed that type of Slurry and irrigation played a role in the vertical distribution of oocysts, with more oocysts recovered from soil columns added liquid Slurry irrespective of the irrigation status. Further studies are needed to determine the effectiveness of different Slurry separation technologies to remove oocysts and other pathogens, as well as whether the application of separated liquid Slurry to agricultural land may represent higher risks for groundwater contamination compared to application of raw Slurry.
Muthanna H Aldahhan - One of the best experts on this subject based on the ideXlab platform.
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anaerobic digestion of animal waste waste strength versus impact of mixing
Bioresource Technology, 2005Co-Authors: Khursheed Karim, Thomas K Klasson, Rebecca Hoffmann, Muthanna H AldahhanAbstract:We studied the effect of mode of mixing (biogas recirculation, impeller mixing, and Slurry recirculation) and waste strength on the performance of laboratory scale digesters. The digesters were fed with 5% and 10% manure Slurry, at a constant energy supply per unit volume (8 W/m3). The experiments were conducted in eight laboratory scale digesters, each having a working volume of 3.73 L, at a controlled temperature of 35+/-2 degrees C. Hydraulic retention time (HRT) was kept constant at 16.2 days, resulting in a total solids (TS) loading rate of 3.08 g/Ld and 6.2 g/Ld for 5% and 10% manure Slurry feeds, respectively. Results showed that the unmixed and mixed digesters performed quite similarly when fed with 5% manure Slurry and produced biogas at a rate of 0.84-0.94 L/Ld with a methane yield of 0.26-0.31 L CH4/g volatile solids (VS) loaded. This was possibly because of the low solids concentration in the case of 5% manure Slurry, where mixing created by the naturally produced gas might be sufficient to provide adequate mixing. However, the effect of mixing and the mode of mixing became prominent in the case of the digesters fed with thicker manure Slurry (10%). Digesters fed with 10% manure Slurry and mixed by Slurry recirculation, impeller, and biogas recirculation produced approximately 29%, 22% and 15% more biogas than unmixed digester, respectively. Deposition of solids inside the digesters was not observed in the case of 5% manure Slurry, but it became significant in the case of 10% manure Slurry. Therefore, mixing issue becomes more critical with thicker manure Slurry.
Naoyuki Kayukawa - One of the best experts on this subject based on the ideXlab platform.
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Characteristics of microencapsulated PCM Slurry as a heat-transfer fluid
AIChE Journal, 1999Co-Authors: Yasushi Yamagishi, Alexander T. Pyatenko, Hiromi Takeuchi, Naoyuki KayukawaAbstract:The hydrodynamic and heat-transfer characteristics of Slurry containing microencap- sulated phase-change materials MCPCMs were investigated experimentally for use as a heat-transfer fluid. Pressure drop and local convective heat-transfer coefficients of the Slurry flows in a circular tube with uniform heat flux were measured. Slurries consisting of ()octadecane C H contained in 2 ? 10- 18 38 ? m-dia. microcapsules and pure water were used. The particle ®olume fractions in the Slurry were ®aried up to 0.3. Results showed that increases in particle ®olume fractions caused the Slurry flow structure to change from turbulent to laminar, and the pressure-drop reduction of the Slurry flow relative to a single-phase water flow was under the same low-rate conditions. The heat-transfer performance of the Slurry also depended on the change in flow structure. When the MCPCMs melted, the local heat-transfer coefficients for turbulent Slurry flows increased relative to those for nonmelting Slurry. This phenomenon was influenced by the MCPCM fraction, the degree of turbulence, and the heating rate at the tube wall. The experimental data will be useful in the design of thermal-energy transportation sys- tems using MCPCM Slurry.