342 research outputs found
An investigation into the fertilizer particle dynamics off-the-disc
The particle size range specifications for two biosolids-derived organomineral fertilizers (OMF) known as OMF10 (10:4:4) and OMF15 (15:4:4) were established. Such specifications will enable field application of OMF with spinning disc systems using conventional tramlines spacing. A theoretical model was developed, which predicts the trajectory of individual fertilizer particles off-the-disc. The drag coefficient (Cd) was estimated for small time steps (10-6 s) in the trajectory of the particle as a function of the Reynolds number. For the range of initial velocities (20 to 40 m s-1), release angles (0Ă° to 10Ă°) and particle densities (1000 to 2000 kg m-3) investigated, the analysis showed that OMF10 and OMF15 need to have particle diameters between 1.10 and 5.80 mm, and between 1.05 and 5.50 mm, respectively, to provide similar spreading performance to urea with particle size range of 1.00 to 5.25 mm in diameter. OMF10 and OMF15 should have 80% (by weight) of particles between 2.65 and 4.30 mm, and between 2.55 and 4.10 mm, respectively. Due to the physical properties of the material, disc designs and settings that enable working at a specified bout width by providing a small upward particle trajectory angle (e.g., 10Ă°) are preferred to high rotational velocities. However, field application of OMF with spinning discs applicators may be restricted to tramlines spaced at a maximum of 24 m; particularly, when some degree of overlapping is required between two adjacent bouts. The performance of granular fertilizers can be predicted based on properties of the material, such as particle density and size range, using the contour plots developed in this study
Pathways for Nutrient Loss to Water; Slurry and Fertilizer Spreading
End of project reportThere are almost 150,000 farms in Ireland and these contribute substantial quantities of N and P to inland and coastal waters. Some of these nutrients are carried from wet soils by overland flow and by leaching from dry soils. Farm practice can reduce the loss from farms by judicious management of nutrients. Improvements are required to diminish export of nutrients without impairing operations on the farm. Literature regarding nutrient loss from agriculture was reviewed in this project and maps were prepared to predict best slurry spreading times around Ireland. Two further maps were prepared to show slurry storage requirement on farms
Research into engineering and operation parameters of mineral fertiliser application machine with new fertiliser spreading tools
Received: February 13th, 2021 ; Accepted: April 15th, 2021 ; Published: April 19th, 2021 ; Correspondence: [email protected] output capacity of the machine for top spreading the soil with solid mineral
fertilisers can be raised by means of increasing its working width. The authors have carried out
field trials and field experiment investigations with the MVU-8 granulated mineral fertilizer
spreading machine equipped with two prototype units of the centrifugal fertiliser spreading tool,
in which the axis can be tilted at different angles to the vertical line. In accordance with the results
of the completed investigations, it has been established that setting the axial tilt angle of the
centrifugal operating device in the fertiliser spreading tool within the range of 25â30° provides
for achieving a productivity of the combined tractor-implement unit for applying mineral
fertilisers at a level of 35â40 ha per working shift hour. The best performance in the fertiliser
application with regard to both the working width and the fertiliser placing distribution uniformity
is ensured at angles of inclination of the disc in the fertiliser spreading tool with respect to the
horizontal plane within the range of 25â30°. At these angles, the uneven distribution of the
fertiliser over the working width is equal to 19.2%, the uneven distribution of the fertiliser along
the unitâs line of travel is equal to 8.9%, while the deviation in the dosage of the applied fertilisers
from the set value is equal to 7.5%
Research into engineering and operation parameters of mineral fertiliser application machine with new fertiliser spreading tools
The output capacity of the machine for top spreading the soil with solid mineral fertilisers can be raised by means of increasing its working width. The authors have carried out field trials and field experiment investigations with the MVU-8 granulated mineral fertilizer spreading machine equipped with two prototype units of the centrifugal fertiliser spreading tool, in which the axis can be tilted at different angles to the vertical line. In accordance with the results of the completed investigations, it has been established that setting the axial tilt angle of the centrifugal operating device in the fertiliser spreading tool within the range of 25â30° provides for achieving a productivity of the combined tractor-implement unit for applying mineral fertilisers at a level of 35â40 ha per working shift hour. The best performance in the fertiliser application with regard to both the working width and the fertiliser placing distribution uniformity is ensured at angles of inclination of the disc in the fertiliser spreading tool with respect to the horizontal plane within the range of 25â30°. At these angles, the uneven distribution of the fertiliser over the working width is equal to 19.2%, the uneven distribution of the fertiliser along the unitâs line of travel is equal to 8.9%, while the deviation in the dosage of the applied fertilisers from the set value is equal to 7.5%
PredviÄanje kotrljanja Äestice Äubriva duĆŸ lopatice centrifugalnog rasipaÄa sa diskom
The paper analyzes the motion of idealized spherical homogeneous fertilizer particle along the straight vane attached to flat rotating disc. The analysis, based on the assumption on the pure rolling of the particle along the vane (without sliding), has been performed in the non-inertial reference coordinate system, which rotates together with the spreader disk. The particle motion along the vane is described by hyperbolic cosine function, which is the solution of the ordinary in-homogenous secondorder differential equation having constant coefficients. Solution of this kind represents an approximation of the real motion of fertilizer particle along the radial vane fixed to horizontal disc rotating at constant angular velocity. However, it can be very useful for optimization of centrifugal spreader design and working parameters, as well as for further analysis of the whole fertilizer spreading process that also includes particle flight.U radu je analizirano kretanje idealizovane, loptaste, homogene Äestice mineralnog Äubriva duĆŸ radijalne lopatice postavljene na rotirajuÄem disku centrifugalnog rasipaÄa Äubriva. Analiza, zasnovana na pretpostavci o kotrljanju Äestice duĆŸ lopatice bez klizanja, izvedena je u neinercijalnom referentnom koordinatnom sistemu koji rotira zajedno sa diskom za rasipanje Äubriva. Kretanje Äestice duĆŸ lopatice je opisano hiperboliÄnom kosinusnom funkcijom, koja predstavlja reĆĄenje obiÄne homogene diferencijalne jednaÄine drugog reda sa konstantnim koeficijentima, koja opisuje dinamiku Äestice. ReĆĄenje ove vrste predstavlja aproksimaciju stvarnog kretanja Äestice Äubriva duĆŸ lopatice diska koji rotira konstantnom ugaonom brzinom. MeÄutim, moĆŸe biti veoma korisno za optimizaciju dizajna centrifugalnog rasprĆĄivaÄa i njegovih radnih parametara, kao i za dalju analizu Äitavog procesa rasipanja Äubriva koji obuhvata i let Äestice u vazduhu po napuĆĄtanju lopatice
Characterisation of organomineral fertilisers derived from nutrient-enriched biosolids granules
Organomineral fertilisers (OMFs) were produced by coating biosolids granules with urea and potash. Two OMF formulations with Nâ:âP2O5â:âK2O compositions: 10â:â4â:â4 (OMF10) and 15â:â4â:â4 (OMF15) were developed for application in grassland and arable crops. Routine fertiliser analyses were conducted on four batches of OMF and biosolids granules and compared with a sample of urea to determine key physical and chemical properties of the materials which affect handling and spreading, soil behaviour, and fertiliser value. Bulk and particle densities were in the range of 608 to 618âkgâmâ3, and 1297 to 1357âkgâmâ3, respectively. Compression tests showed that OMF particles undergo deformation followed by multiple failures without disintegration of the granules when vertical load was applied. Static particle strength was between 1.18 and 4.33âNâmmâ2 depending on the particle diameter. The use of a model for fertiliser particle distribution studies showed that OMF granules should be between 1.10 and 5.50âmm in diameter with about 80% of the particles in the range of 2.25 to 4.40âmm to enable application at 18âm tramline spacing. This research utilises novel technology to improve the fertiliser value of biosolids, reduce disposal costs, and deliver a range of environmental benefits associated with recycling
Kimberley Research Station progress report, 1964 : soil fertility and plant nutrition
BEFORE 1963, very little work, other than that described in Burvill\u27s original report, had been done on the analysis of Ord soils, nor had their fertility status been clearly defined
Kimberley Research Station progress report, 1964 : cotton
SINCE 1960 cotton has occupied the prominent place in the Station\u27s research programme.
Considerable progress has been made in all aspects of cotton culture (Thomson and Basinski 1962b; Thomson 1962.
Kimberley Research Station progress report, 1964 : introduction
THE Ord Irrigation settlement has recently planted its second commercial crop of cotton.
Research and planning toward the development project has been systematic over the last 20 years and has included hydrological surveys and dam-site investigations by the Public Works Department soil and topographical surveys by both the Department of Agriculture and C.S.I.R.O., and concerning farming methods both by research station investigations and by pilot farming
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