Manure Particles Research Articles

Wheat straw biochar as an additive in swine manure Composting: An in-depth analysis of mixed material particle characteristics and interface interactions

In recent research, biochar has been proven to reduce the greenhouse gases and promote organic matter during the composting. However, gas degradation may be related to the microstructure of compost. To investigate the mechanism of biochar additive, composting was performed using swine manure, wheat straw and biochar and representative solid compost samples were analyzed to characterize the mixed biochar and compost particles. We focused on the microscale, such as the particle size distributions, surface morphologies, aerobic layer thicknesses and the functional groups. The biochar and compost particle agglomerations gradually became weaker and the predominant particle size in the experiment group was < 200 μm. The aerobic layer thickness (Lp) was determined by infrared spectroscopy using the wavenumbers 2856 and 1568 cm−1, which was 0–50 μm increased as composting proceeded in both groups. The biochar increased Lp and facilitated oxygen penetrating the compost particle cores. Besides, in the biochar-swine manure particle interface, the aliphatic compound in the organic components degraded and the content of aromaticity increased with the composting process, which was indicated by the absorption intensity at 2856 cm−1 decreasing trend and the absorption intensity at 1568 cm−1 increasing trend. In summary, biochar performed well in the microscale of compost pile.

ЭКСПЕРИМЕНТАЛЬНЫЕ ИССЛЕДОВАНИЯ ПРОЦЕССА ПЕРЕМЕШИВАНИЯ ЖИДКОГО НАВОЗА МИКСЕРОМ С КОНИЧЕСКИМ КОЖУХОМ

Mixing in various industries is widely used to obtain homogeneous media in composition, as well as to intensify the processes of mass and heat transfer. So, in livestock, various types of equipment are used to mix liquid manure stored in a manure storage facility. The mixing method and equipment used for its implementation’s choice is due to the aggregate state of the manure mass stored in the manure storage. Most of the currently existing the liquid manure mixing equipment works mainly in stationary regime, at working bodies’ constant angular velocity. At this manure mass volume method of influencing on the manure storage, there are zones in which the mixed media’s flow rate is low, and manure particles do not participate in their movement, and therefore mixing quality is deteriorated. The a mixer with an agitator’s experimental studies results that are encircled by a conical casing, are presented. A mixer is used on farms to mix liquid manure in order to a homogeneous consistency obtaining. This specified unit’s working body is a stirrer, that in depending on its design, can have from two till four blades. However, this stirrer elements’ design already have an upper, its operational capabilities’ limit is well known. In order forming homogeneous manure mass’s unit cost reducing, the flow transported power for stirrer blades possibility increasing was studied. For this task’s performing, a conical casing along the blades’ outer radius was installed. Based on this experimental studies to solve energy saving and stored manure mixing intensification’s problems, the conical mixer’s casing optimal parameters have been determined. The experimental studies’ results of manure mixer with a conical casing’s technical parameters are presented. The dependences of liquid manure mixing process energy intensity on casing nozzle diameter, mixer relative inclination outlet’s angle to the horizontal plane and the number of stirrer’s revolutions are determined.

Leaching of Sulfadiazine and Florfenicol in an Entisol of a Chicken-Raising Orchard: Impact of Manure-Derived Dissolved Organic Matter

Antibiotic pollution from manured farmland soils is a major public concern, and their potential interaction with manure particles and/or manure–dissolved organic matter (DOM) often complicates their leaching behaviour. This study investigated the leaching of sulfadiazine (SDZ) and florfenicol (FFC) with manure-DOM in undisturbed field lysimeters and repacked soil columns under natural and simulated rainfall conditions. The results showed that manure-DOM reduced SDZ mass flux, but soil hydrological processes and heavy rainfall events led to accelerated leaching. FFC was more prone to leaching in a manured plot (0.48 µg m−2 h−1) compared to the control (0.12 µg m−2 h−1), suggesting DOM facilitated transport of FFC in the field lysimeter study via cotransport mechanisms favored by abundant macropores in the study site. In contrast, SDZ and FFC mobility were reduced in repacked soil columns under manure-DOM conditions, suggesting complexation and adsorption in matrix pores. Two kinetic site models and two-site nonequilibrium adsorption models revealed the existence of nonequilibrium conditions and kinetic sorption processes in the repacked column. FFC exhibited lower leaching potential compared to SDZ in both the repacked column and natural field conditions. Redundancy analyses revealed that FFC had a close relationship with humic-like components (C1 and C3), but SDZ was more related to the protein-like components (C2) of DOM. The presence of manure-DOM may decrease the ecological risks of highly mobile antibiotics under matrix flow through complexations and adsorption. However, a similar scenario in macroporous flow under heavy rainfalls may lead to accelerated leaching.

Nano and micro manure amendments decrease degree of phosphorus saturation and colloidal phosphorus release from agriculture soils

The manure fertilizer increases the phosphorus (P) saturation of soils and the colloidal P release to water bodies. Manure of different particle-sizes may have different effects on colloidal P release by soil, and to date there is limited knowledge on colloidal P release from soils amended with different size manures. We produced sheep micro- (SMicro) and nano-manure (SNano), and poultry micro- (PMicro), nano-manure (PNano) from bulk samples by wet fractionation method. The fractionation reduced the P contents of micro- and nano-manures, and enriched them in ash and calcium, iron (Fe), magnesium, and aluminum (Al) phosphate minerals compared with the bulk manures. The degree of P saturation (DPS) in Anthorsol and Cambisol was decreased (SMicro, 17.6 and 17.2 %; SNano, 14.5 and 13.3 % and PMicro, 19.0 and 19.7 mg kg−1; PNano, 17.0 and 14.3 mg kg−1) and released less colloidal P (SMicro, 3.12 and 3.78 mg kg−1; SNano, 3.01 and 3.56 mg kg−1 and PMicro, 3.34 and 3.92 mg kg−1; PNano, 3.21 and 3.65 mg kg−1) than the soils receiving the bulk manures. The decrease in colloidal P was correlated with less DPS in both soils amended with micro and nano manures. That is, the only measurable effect of manure particle size on colloidal P release from the amended soils was due to chemical fractionation during separation of the size fractions. It was suggested that nano and micro manures were the effective approach to reduce colloidal P release from manure amended soils.

Effects of solid manure particle fractionation on transport, retention, and release of Escherichia coli

Understanding the effect of manure particle fractionation on transport, retention, and release of bacteria plays a critical role in manure management and environmental policies that address soil and water bacterial pollution. Compared to soil particle size, there is less understanding of the importance of solid manure particle size and fractionation on bacterial fate and transport in soils. Four different cow manure particle sizes (0.25, 0.5, 1, and 2 mm) were used to investigate Escherichia coli fate in a saturated loamy sand soil. Leaching experiments were performed for up to 20 pore volumes. Preferential transport of chloride mitigated as manure particle size increased. The larger manure fractions (1 and 2 mm) showed greater heterogeneity in bacteria transport and release; smaller manure fractions (0.25 and 0.5 mm) had a greater bacteria retention with retarded release. Bacteria release was associated with transport and re-entrainment of manure particles through soil columns. The results highlighted the contribution of fine and transported particles as of primary importance for retention near the surface and transporting bacteria in soil. Similar retention shapes ( i.e., exponential) for different fractions illustrated the similarity of manure source, where greater retention was observed at 0 − 3 cm depth for the smallest (0.25 mm) and largest (2 mm) manure fractions. The findings also highlighted the dependency of bacteria transport, retention, and release on manure physical fractionation, which should be considered in managing soil and manure practices in the field. • The more heterogeneous manure fractions, the greater bacteria transport and release. • The smaller manure particles, the greater bacteria retention and retarded release. • The greater re-entrainment of manure particles, the greater bacteria release.

Differences in the sediment composition of wind eroded sandy soils before and after fertilization with poultry manure

Wind erosion is known to be a gradual process of soil degradation on arable lands. Poultry manure fertilization is a common practice to improve physical, chemical and biological soil properties, and is thus an essential part to maintain soil fertility. Shortly after incorporation, poultry manure and soil particles are loosely adjacent without any bonding. This supposedly affects the susceptibility of soils to wind erosion and influence the physical and chemical composition of the wind-eroded sediment. Wind tunnel experiments were conducted with three wind speeds (8, 11, 14 m s−1) and four sandy soils, each fertilized with poultry manure in a common rate of 6 t ha−1. Incorporation of manure in the soils changed the particulate organic matter (POM) composition resulting in increased median particle diameters, carbon contents and hydrophobicity. Wind erosion caused a preferred release of manure particles already at wind speeds close above the threshold of 7 m s−1 with the greatest sorting effects in size, shape, and density of the particles. Thus, wind erosion immediately leads to losses of the added organic material. At higher wind speeds the sediment composition rather corresponds to the entire soil or soil-manure mixtures. Depending on the wind speed and total soil loss, potential manure losses between 101 and 854 kg ha−1 were accounted, which are 1.7–14% of the fertilization rate. The results indicate a risk of substantial loss or redistribution of poultry manure by wind erosion immediately after incorporation.

Effects of Mechanical Refining on Anaerobic Digestion of Dairy Manure.

Mechanical refining (MR) is a cost-effective pretreatment in biochemical conversion processes that is employed to overcome biomass recalcitrance. This work studied the effects of MR on biogas and methane produced by the anaerobic digestion (AD) of dairy manure. The cumulative gas volume and yield from the AD of manure refined at 6k revolutions increased by 33.7 and 7.7% for methane and by 32.0 and 6.4% for biogas, respectively, compared to the unrefined manure. This enhancement was reached by increasing manure solubilization, reducing particle size, and achieving external fibrillation and internal delamination of fibers in manure. However, the highly refined manure (subjected to 60k revolutions) exhibited methane and biogas yields that were reduced by 9.5 and 1.5%, respectively. This decrease was observed because the pore structure was ruptured, and finely ground manure particles were aggregated together at high revolutions (60k), thereby inhibiting the release of organic matter from the manure. Therefore, this study indicates that the MR for pretreatment of dairy manure could have great potential for significantly enhancing AD of dairy manure. Further studies will include optimization of conditions of mechanical refining (i.e., mechanical intensity, process time), a continuous AD of dairy manure pretreated by the MR, and scale-up with cost evaluation.

Определение вероятности проскока частиц навоза через слои ферромагнитных элементов в аппаратах вихревого слоя

Theoretical dependences are presented for determining the probability of penetration of manure particles through the layers of rotating ferromagnetic elements in the vortex layer device taking into account their number and geometrical dimensions, and parameters of the working area.

Effects of pyrolysis temperature and reaction time on the performance of swine-manure-derived bio-binder

Swine-manure-derived bio-binder can solve the problem of environmental pollution caused by the accumulation of solid waste from swine manure, and realize the replacement of asphalt by sustainable road construction materials. The main purpose of this study is to study the influence of pyrolysis conditions on the performance of swine-manure-derived bio-binder, the swine manure particles were cracked at 5 pyrolysis temperatures and 2 reaction times. Ten kinds of swine-manure-derived bio-oil were prepared, and 15% bio-oil were used to partially replace petroleum asphalt to prepare corresponding bio-binder. The effects of pyrolysis conditions on the penetration, softening point, ductility, water absorption and the rheological properties of bio-binder were tested. The results show that the maximum bio-oil yield of 1 s reaction time at 550 °C pyrolysis temperature was 45.1%. The high temperature stability of bio-binder is better than that of virgin asphalt. The high temperature stability of bio-binder gradually decreases with the pyrolysis temperature and reaction time of bio-oil. The fatigue performance and low-temperature crack resistance of the bio-binder are poorer than that of virgin asphalt on the low pyrolysis temperature, but those performances will be gradually improved with the pyrolysis temperature. The low-temperature crack resistance of the binder can be improved by prolonging the cracking reaction time under a certain pyrolysis temperature. Considering the yield of bio-oil and the performance of bio-binder comprehensively, the swine-manure-derived bio-oil at a pyrolysis temperature of 550 °C and a reaction time of 1 s is the most suitable for the preparation of bio-binder.

Airborne bacterial emission fluxes from manure-fertilized agricultural soil.

This is the first study to quantify the dependence on wind velocity of airborne bacterial emission fluxes from soil. It demonstrates that manure bacteria get aerosolized from fertilized soil more easily than soil bacteria, and it applies bacterial genomic sequencing for the first time to trace environmental faecal contamination back to its source in the chicken barn. We report quantitative, airborne emission fluxes of bacteria during and following the fertilization of agricultural soil with manure from broiler chickens. During the fertilization process, the concentration of airborne bacteria culturable on blood agar medium increased more than 600000-fold, and 1m3 of air carried 2.9×105 viable enterococci, i.e. indicators of faecal contamination which had been undetectable in background air samples. Trajectory modelling suggested that atmospheric residence times and dispersion pathways were dependent on the time of day at which fertilization was performed. Measurements in a wind tunnel indicated that airborne bacterial emission fluxes from freshly fertilized soil under local climatic conditions on average were 100-fold higher than a previous estimate of average emissions from land. Faecal bacteria collected from soil and dust up to seven weeks after fertilization could be traced to their origins in the poultry barn by genomic sequencing. Comparative analyses of 16S rRNA gene sequences from manure, soil and dust showed that manure bacteria got aerosolized preferably, likely due to their attachment to low-density manure particles. Our data show that fertilization with manure may cause substantial increases of bacterial emissions from agricultural land. After mechanical incorporation of manure into soil, however, the associated risk of airborne infection is low.

Relationship between the particle size and nutrient distribution of feces and nutrients in pigs and dairy cows and the efficiency of solid-liquid separation

In this paper, pig and dairy manure were used as materials, and the particle size distribution of pig and dairy manure was analyzed according to different particle sizes of <0.15, 0.15-0.5, 0.5-1.0 and> 1.0mm. At the same time, NPK in four different particle sizes were analyzed. The nutrient content was solid-liquid separated by using XY-type spiral livestock and poultry manure solid-liquid separators under 0.5 and 1.0mm sieve screens. The mechanical solid-liquid separation was used to analyze the solids and nutrients of the corresponding particle size feces. Recovery efficiency. The results show that the particle size distribution of pig and cow manure is mainly <0.15mm small particles. Such small particles account for 57.99% -68.34% of the weight of the manure. The particle size of dairy manure particles is larger than that of pig manure. Less than fattening pigs and lactating cow feces. Nearly 80% of N, P, and K nutrients in pig and dairy manure are water-soluble or exist in small particles <0.15mm. The percentage of N and P nutrient recovery from solids and solids obtained from mechanical solid-liquid separation of feces is higher than the proportion of fecal particles and nutrients from the corresponding screen pore size. %, N, P nutrient recovery rates were 7.14-19.71, 7.38-21.18%, respectively.

Experimental study of the ignition and combustion characteristics of cattle manure under different environmental conditions

This paper investigates the ignition and combustion characteristics of cattle manure particles under different environmental conditions, and analyses the ash produced by combustion. The cattle manure particles were fixed in a vertical heating furnace, and a thermocouple and camera recorded the internal temperature and combustion process of the particles. The environmental temperature of the combustion chamber was set at 873, 973 and 1073 K, and the oxygen concentrations were 10–80%; the gas flow rate was set to 10, 20 and 30 L/min, respectively. The experimental results show that the effect of environmental temperature on the ignition and combustion of cattle manure particles is most obvious. Under most circumstances, the volatile matter begins to ignite before the particulate matter. As the environmental temperature and oxygen concentration increase, the condition of ignition and combustion were improved, and the internal ignition temperature, ignition delay and volatile combustion time were reduced. In addition, thermogravimetric experiments on powdered cattle manure were also carried out at four heating rates, and four peaks were presented in the derivative thermogravimetric (DTG) curve, corresponding to four different stages of cattle manure combustion.

A new extraction procedure to abate the burden of non-extractable antibiotic residues in manure

Through agricultural soil fertilization using organic manure, antibiotic residues can accumulate in the environment. In order to assess the risks of environmental pollution by veterinary drugs, monitoring of manure for antibiotic residues is necessary. As manure is a complex matrix, extraction of antibiotics proved to be challenging. In this study, 24 extraction solvents were assessed for the extraction of residues from manure representing ten antibiotics from the antibiotic classes tetracyclines, quinolones, macrolides, lincosamides and sulfonamides. Especially for the tetracyclines and quinolones the extraction solvent selection is critical, due to high fractions of non-extractable residues especially when using aqueous solvents (62–77% and 90–95% respectively when using milli-Q water). In contrast, sulfonamides can effectively be extracted with aqueous solvents. Overall, 0.125% trifluoroacetic acid in acetonitrile in combination with McIlvain-EDTA buffer proved to be the most effective extraction solvent. A longitudinal study pointed out that most antibiotics bind to solid manure particles instantaneously after addition. Trimethoprim is an exception, but because by using the optimal extraction solvent, the optimum fraction of bound residues is desorbed, this does not hamper quantitative analysis when using spiked manure quality control samples. Based on these new insights, the current in-house multi-residue LC-MS/MS method for manure analysis, containing 48 antibiotics, was revised, additionally validated and applied to 34 incurred manure samples.

Characterization and Impact of Cattle Manure Particle Size on Physical Properties of Sandy Soils

Sandy soils have poor physical properties, which cause them to drain quickly and not hold water well; however, with the addition of cattle manure, sandy soil can be improved. Therefore, experiments were conducted to investigate the characterization and impact of different particle sizes of cattle manure (CMS) on improving some physical properties of sandy soil and thus the yield of lettuce. Cattle manure was ground to powder and was sieved with three different Particle sizes 4.76-2 (CMS1), 2-0.8 (CMS2), 0.8-0.4 (CMS3) mm. Some physical properties were measured for different Particle sizes of manure. A batch of sorption experiments was carried out to study the role of different Particle sizes of manure on adsorption of N, P and K from aqueous solution. Two experiments were carried out on sandy soil (pots and field) to study the impact of adding CMS (5 ton/fed) to enhance some physical properties of sandy soil. The results indicated that the physical properties of cattle manure changed based on particle size fractionation, where Bulk density and saturated water holding capacity increased as particle size decreased, while porosity reduced as particle size decreased. The results of the sorption parameters of N, P and K on different particle sizes of manure indicated that maximum sorption occurred on CMS 3 for both P and K according to Langmuir and Freundlich sorption models. Two experiments showed that CMS had affected significantly the total porosity (TP), bulk density (Bd), slowly drainable pores (SDP), water holding pores and (WHP) available water (AW) in comparison to control. The CMS had a slight effect on Quickly-drainable pores (QDP) and fine capillary pores (FCP) as compared to the control in both experiments. Fresh weight, dry weight and number of leaf lettuce increased significantly with decreasing particle sizes of cattle manure as compared to control.

Spatial nitrifications of microbial processes during composting of swine, cow and chicken manure.

Composting is a widely-used method to recycle the nutrients in livestock manure for agriculture. The spatial stratifications of microbial processes inside the manure particle that determine organic and nitrogen transformation are virtually unclear. Here, we show the evolution of the interior microenvironment of swine, cow and chicken manure by using microelectrodes during forced-aeration composting. Composting has generally been regarded as an aerobic bioprocess, however, the long-existing of a large anoxic zone inside these manures was confirmed during the active phase in this study. The profile of the oxidation–reduction potential dramatically decreased first and then gradually increased. The spatial difference in the ammonia concentration was not significant, but nitrate concentration continuously decreased with depth. The anoxic condition within the manure particle was demonstrated to be a primary cause of the severe ammonia emission and the long composting period. These founding provided a new insight toward “aerobic” composting process and a sound foundation for the development of efficient composting technology.

Transformation of organic matters in animal wastes during composting

The transformation of organic matters in swine, cow and chicken manures was compared and evaluated using elemental analysis, FTIR, 13C NMR, pyrolysis/GC/MS, Biolog and multiple fluorochrome over 60 days composting. The results revealed that cow manure exhibited the greatest C/N and aromaticity, whereas chicken manure exhibited the highest nitrogen and sulfur contents. O-alkyl-C was predominant carbon structure in the three manures. Alkyl-C and carboxyl-C were decomposed dramatically in initial 10 days, and mineralization of O-alkyl-C dominated the curing stage. During pyrolysis of chicken, cow, and swine manures, the majority products were fatty acids, phenols and cholestene derivatives, respectively, however, phenols and cholestene derivatives were strongly reduced in the mature manures. Furthermore, microorganisms in the raw cow, chicken and swine manure demonstrated the highest degradation capabilities for carbohydrates, lipids and amino acids, respectively. Spatial differences in the contents of solid organics in the manure particles were negligible through detection by multiple staining methods during composting.

Mechanism and kinetics of organic matter degradation based on particle structure variation during pig manure aerobic composting

Characterization of the dynamic structure of composting particles may facilitate our understanding of the mechanisms of organic matter degradation during pig manure–wheat straw aerobic composting. In this study, changes in the size, shape, pores, chemical compositions, and crystal structures of pig manure particles during composting were investigated. The results showed that the median diameter (D50) decreased exponentially, while the particle aspect ratio and sphericity were unchanged, suggesting that particles were degraded uniformly along different radial directions. Pores had a mean diameter of 15–30μm and were elliptical. The particle porosity increased linearly mainly because of hemicellulose degradation. Furthermore, the influence of particle structure variation on the first order rate constant (k) of organic matter degradation was corrected, which may facilitate the optimization of operation conditions. The k value was proportional to the reciprocal of D50 according to the specific surface area of particles, and it decreased with increased porosity due to the stabilized chemical compositions and crystal structures of particles. However, the applicability of these data to other composting materials should be verified.

Characterization of the Dynamic Thickness of the Aerobic Layer during Pig Manure Aerobic Composting by Fourier Transform Infrared Microspectroscopy

A new method for characterizing the aerobic layer thickness in pig manure based on Fourier transform infrared microspectroscopy (FTIRM) is presented to improve the anaerobic/aerobic co-process mechanism, to ensure adequate oxygen supply and, thus, minimize methane emissions during aerobic composting. Freeze-dried manure particles were microtomed into 10 μm thick sections; the spectral range, spectral resolution, and pixel dimensions in the transmission spectra were 4000-650 cm(-1), 16 cm(-1), and 6.25 × 6.25 μm, respectively. A mean spectrum of 16 scans was used for the second-derivative analysis with nine smoothing points. This is the first attempt at determining the oxidation profile of composting particles according to the radial variations in second-derivative spectra at 2856 and 1568 cm(-1), which are attributed to the reactants and products of the oxidation, respectively. In addition, an intermediate area is detected between the aerobic layer and anaerobic core. The experimental values of the aerobic layer thickness are consistent with the estimates, and an exponential increase is observed, which is influenced by multiple dynamic factors. However, the contribution of each factor to dynamic variations in the aerobic layer thickness should be investigated using available methods.

Optimal Physical Pretreatment Conditions for the Release of Carbohydrate and Protein from Dairy Manure

Various physical factors including particle size, pH, temperature and so on may influence the release of organic materials from dry dairy manure. The effect of these factors on release of protein and carbohydrate was investigated in this study using Box-Behnken Experimental Design with three factors (particle size, temperature and pH) at three levels. Test results suggested that particle size of 0.15-0.25 mm accounted for almost half of the dry manure particles and the optimum condition for release of protein and carbohydrate were pH 2, particle size 1.0-1.4 mm under reaction temperature of 90 oC, under which the protein and carbohydrate release rates could reach 1570.57 and 2813.29 mg l-1, respectively. The degree to which these factors affected organics release was in the order from high to low of temperature &gt; particle size &gt; pH.

Relationships Between Manure Particle and E. coli Transport from Direct Fecal Deposits Under Steady-State Flows

Pathogens are the leading cause of water quality impairments as defined by the US Environmental Protection Agency and their transport within water bodies is poorly understood. Because of this, watershed-scale, water quality models often have poor bacterial prediction capabilities. To improve the understanding of in-stream bacterial transport, a cow pie was deposited in a recirculating flume with flows ranging from 0.0102 to 0.0176 m3 s−1. Water samples were collected and analyzed for Escherichia coli concentration, E. coli attached fraction, and turbidity. E. coli concentrations ranged from 4.72 × 103 to 1.70 × 105 CFU 100 mL−1 and turbidity ranged from 1.93 to 369 NTU over both locations and all times. The percentage of E. coli attached to particles ranged from an average of 2.9 to 31 % downstream of the fecal deposition point. Spearman correlation analysis demonstrated that bacteria concentrations were significantly related with water depth (ρ = 0.128, p = 0.018), and the concentration of attached bacteria was significantly correlated with both the total concentration of E. coli (ρ = 0.4081, p = 0.009) and turbidity (ρ = 0.3627, p = 0.0214). This analysis is useful to indicate parameters that should be considered when monitoring or predicting bacteria transport in streams.