342 research outputs found

    An investigation into the fertilizer particle dynamics off-the-disc

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    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 (0° to 10°) 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., 10°) 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

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    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

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    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 25–30° provides for achieving a productivity of the combined tractor-implement unit for applying mineral fertilisers at a level of 35–40 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 25–30°. 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 unit’s 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

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    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 25–30° provides for achieving a productivity of the combined tractor-implement unit for applying mineral fertilisers at a level of 35–40 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 25–30°. 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 unit’s 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%

    Predviđanje kotrljanja čestice đubriva duĆŸ lopatice centrifugalnog rasipača sa diskom

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    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 čestice mineralnog đubriva duĆŸ radijalne lopatice postavljene na rotirajućem disku centrifugalnog rasipača đubriva. Analiza, zasnovana na pretpostavci o kotrljanju čestice duĆŸ lopatice bez klizanja, izvedena je u neinercijalnom referentnom koordinatnom sistemu koji rotira zajedno sa diskom za rasipanje đubriva. Kretanje čestice duĆŸ lopatice je opisano hiperboličnom kosinusnom funkcijom, koja predstavlja reĆĄenje obične homogene diferencijalne jednačine drugog reda sa konstantnim koeficijentima, koja opisuje dinamiku čestice. ReĆĄenje ove vrste predstavlja aproksimaciju stvarnog kretanja čestice đubriva duĆŸ lopatice diska koji rotira konstantnom ugaonom brzinom. Međutim, moĆŸe biti veoma korisno za optimizaciju dizajna centrifugalnog rasprĆĄivača i njegovih radnih parametara, kao i za dalju analizu čitavog procesa rasipanja đubriva koji obuhvata i let čestice u vazduhu po napuĆĄtanju lopatice

    Characterisation of organomineral fertilisers derived from nutrient-enriched biosolids granules

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    Organomineral fertilisers (OMFs) were produced by coating biosolids granules with urea and potash. Two OMF formulations with N : P2O5 : K2O compositions: 10 : 4 : 4 (OMF10) and 15 : 4 : 4 (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 618 kg m−3, and 1297 to 1357 kg m−3, 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 4.33 N mm−2 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 5.50 mm in diameter with about 80% of the particles in the range of 2.25 to 4.40 mm to enable application at 18 m 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

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    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

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    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

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    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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