Energetic relationships for crushing of soil clods

2006 ◽  
Vol 2 (1) ◽  
pp. 51-72
Author(s):  
István Patay ◽  
Virág Sándor
Keyword(s):  
Moisture Content ◽  
Specific Energy ◽  
Soil Moisture Content ◽  
Energy Requirement ◽  
Clay Content ◽  
Clay Soils ◽  
Rigid Support ◽  
Soil Plasticity ◽  
Specific Energy Requirement ◽  
The Relationship

Clod crushing is a principal problem with soils of high clay content. Therefore, there is a need for determining the conditions for clod breaking and clod crushing. The objective of the work was to develop a special purpose tool for single clod breaking both by rigid support of the clod and by a single clod supported by soil and to develop a machine for clod crushing. Furthermore, the purpose was to determine the relationship between the specific energy requirement for clod crushing in the function of soil plasticity and the soil moisture content by the means of the developed tool and machine. The main result of the experiments is summarized in a 3D diagram where the specific energy requirement for soil clod crushing is given in the function of the moisture content and the plasticity index for different clay soils.

scholarly journals Development of a Hammer Mill with Double Sieving Screens

2020 ◽  
Vol 5 (5) ◽  
pp. 617-621
Author(s):  
Oluyemisi Adebanjo Ojomo ◽  
A. J. Fawohunre
Keyword(s):  
Moisture Content ◽  
Specific Energy ◽  
Energy Requirement ◽  
Hammer Mill ◽  
Performance Indices ◽  
Dual Purpose ◽  
Specific Energy Requirement ◽  
Level Of Significance ◽  
Machine Speed ◽  
The Relationship

A hammer mill with double sieving device was designed and fabricated from locally available materials for grinding grains and other agricultural products. The conceptual design was based on the principle of design by analysis. The test carried out on the machine showed that the crushing capacity of the machine is 51.5 Kh/hr. The moisture content, machine speed and the interaction between them had significant effect on the milling power and specific energy requirement at 5 % level of significance. Milling power and specific energy requirement of the machine increased with increase in moisture content. The maximum crushing efficiency of 79.3 %, minimum milling power and specific energy requirement of 0.09 Kw and 3.04 Kwh/mg respectively were obtained at moisture content of 8 % (wb) and machine speed of 2000 rpm. Regression models that could be used to express the relationship existing between the hammer mill performance indices, product moisture content and machine speed were established. The machine has dual purpose for either electric motor or petrol engine.

scholarly journals DEVELOPMENT OF WOOD GRINDING. 3. FURTHER TESTING OF GRINDING MODELS

2021 ◽  
Vol 55 (7-8) ◽  
pp. 795-797
Author(s):  
BRUNO LÖNNBERG
Keyword(s):  
Energy Balance ◽  
Moisture Content ◽  
Specific Energy ◽  
Energy Requirement ◽  
Wood Properties ◽  
Wood Moisture Content ◽  
Critical Examination ◽  
Stone Surface ◽  
Wood Moisture ◽  
Specific Energy Requirement

"The study is the continuation of a sequence of works devoted to describing the mechanisms occurring during stone grinding of wood. This part was aimed at further testing of pressurised grinding of spruce wood, which was conducted under controlled laboratory conditions. Testing of the developed theoretical model for power ratio (Pc/Pt) versus energy specific production (Ġw/Pt) produced linears for data representing constant wood moisture content. However, the linears showed almost identical results for fresh woods, and also for drier wood, e.g. wood containing saturated fibres and air-dried wood, although one would expect some differences due to the widely varying constant moisture, from 65% to 15% moisture content. Simplification of the model resulted in (cw + X cm) ΔTp-w ≈ Pt / Ġw, and it led to specific linears, when the members as such were correlated between themselves at several constant wood moisture contents. The results were briefly as follows. Increasing wood feed rate – 0.7, 1.0 and 1.3 mm/s – decreased the specific energy requirement, while increased stone surface speed – 20 and 30 m/s – increased it. The left-hand member or the “X-factor” as named in this context, correlated with the right-hand member or the specific energy requirement and resulted in declining linears. The lower the wood moisture content – 65, 58, 44, 28 and 15% – the smaller was the linear declination, and also the difference due to stone surface speed. The application of an energy balance could be useful in searching for a working wood grinding model. Such a model would enable critical examination of wood grinding conditions. Also, it would help understanding the mechanism of various factors, such as grinding parameters, wood properties and stone burr and sharpness. It seems that there are factors that are not known well enough for further development of grinding. Shower water flow and temperature affect the stone surface temperature as known, but their significance for the energy balance or grinding mechanism are not known. Also, the thin film of pulp slurry between the stone surface and the heat activated wood layer is evidently a significant factor that is connected to the local energy transfer. "

scholarly journals Geoelectric method applied in correlation between physical characteristics and electrical properties of the soil

2017 ◽  
Vol 2 (2) ◽  
pp. 37 ◽  
Author(s):  
Antonio Marcelino Silva Filho ◽  
Carlos Leandro Borges Silva ◽  
Marco Antonio Assfalk Oliveira ◽  
Thyago Gumeratto Pires ◽  
Aylton José Alves ◽  
...  
Keyword(s):  
Electrical Resistivity ◽  
Soil Moisture ◽  
Electrical Properties ◽  
Moisture Content ◽  
Soil Compaction ◽  
Clay Content ◽  
Physical Characteristics ◽  
Soil Dynamics ◽  
Different Types ◽  
The Relationship

This paper presents the study of the relationship between electrical properties and physical characteristics of the soil. Measures of apparent electrical resistivity of the soil were made for different types of soil, varying moisture content gradually while maintaining a constant compaction, and then varying the compaction and relating it to a constant humidity. Development of a correlation surface is proposed in order to identify granulometry of the soil from moisture and compaction measurements. For the study of spatial variability, two areas were chosen to allow the change of moisture content and compaction in order to verify the measurement capacity of apparent electrical resistivity of the soil as methodology to identify change in soil dynamics. Results obtained show correlations among apparent electrical resistivity of the soil, moisture, soil compaction and clay content.

Soil Type, Soil Moisture, and Field Slope Influence the Horizontal Movement of Salmonella enterica and Citrobacter freundii from Floodwater through Soil

2016 ◽  
Vol 80 (1) ◽  
pp. 189-197 ◽  
Author(s):  
MARY THERESA CALLAHAN ◽  
SHIRLEY A. MICALLEF ◽  
ROBERT L. BUCHANAN
Keyword(s):  
Soil Moisture ◽  
Moisture Content ◽  
Soil Type ◽  
Soil Moisture Content ◽  
Clay Content ◽  
Horizontal Movement ◽  
Initial Soil Moisture ◽  
Salmonella Newport ◽  
Initial Soil ◽  
Rate Of Decline

ABSTRACT Pathogens in soil are readily mobilized by infiltrating water to travel downward through the soil. However, limited data are available on the horizontal movement of pathogens across a field. This study used a model system to evaluate the influence of soil type, initial soil moisture content, and field slope on the movement of Salmonella enterica serovar Newport across a horizontal plane of soil under flooding conditions. Three soil types of varying clay content were moistened to 40, 60, or 80% of their maximum water-holding capacities and flooded with water containing 6 log CFU/ml Salmonella Newport and Citrobacter freundii, the latter being evaluated as a potential surrogate for S. enterica in future field trials. A two-phase linear regression was used to analyze the microbial populations recovered from soil with increasing distance from the flood. This model reflected the presence of lag distances followed by a quantifiable linear decrease in the population of bacteria as a function of the distance from the site of flooding. The magnitude of the lag distance was significantly affected by the soil type, but this was not attributable to the soil clay content. The rate of the linear decline with distance from the flood zone was affected by soil type, initial soil moisture content, and soil incline. As the initial soil moisture content increased, the rate of decline in recovery decreased, indicating greater bacterial transport through soils. When flooding was simulated at the bottom of the soil incline, the rate of decline in recovery was much greater than when flooding was simulated at the top of the incline. There was no significant difference in recovery between Salmonella Newport and C. freundii, indicating that C. freundii may be a suitable surrogate for Salmonella Newport in future field studies.

Effect of Temperature and Moisture on Aminocyclopyrachlor Soil Half-Life

2013 ◽  
Vol 27 (3) ◽  
pp. 552-556 ◽  
Author(s):  
Katie L. Conklin ◽  
Rodney G. Lym
Keyword(s):  
Moisture Content ◽  
Great Plains ◽  
Soil Moisture Content ◽  
Organic Matter Content ◽  
Clay Content ◽  
Matter Content ◽  
Effect Of Temperature ◽  
Northern Great Plains ◽  
Invasive Weeds ◽  
Crop Species

Aminocyclopyrachlor will control a variety of invasive weeds but may injure sensitive plant species if seeded into treated soil too soon after application. Aminocyclopyrachlor 50% dissipation time (DT50) ranged from 3 to > 112 d in four soils from the Northern Great Plains. The DT50was dependent on several factors including soil type, moisture content, and temperature. Across four different soil textures, aminocyclopyrachlor dissipation generally increased as soil moisture content increased, but moisture had less of an impact in sandy soils. Aminocyclopyrachlor dissipation also increased as temperature increased in the four soils. The most rapid dissipation occurred in soils with higher clay content, which also had the highest organic matter content of the soils evaluated, and an average DT50of less than 20 d. Seeding sensitive pasture, range, or crop species after aminocyclopyrachlor applications should be done with caution since the herbicide has potential for long persistence in the soil.

scholarly journals HUBUNGAN KETERSEDIAAN AIR TANAH DAN SIFAT-SIFAT DASAR FISIKA TANAH

2004 ◽  
Vol 6 (2) ◽  
pp. 46-50
Author(s):  
Kukuh Murtilaksono ◽  
Enny Dwi Wahyuni
Keyword(s):  
Organic Matter ◽  
Soil Moisture ◽  
Moisture Content ◽  
Soil Moisture Content ◽  
Organic Matter Content ◽  
Clay Content ◽  
Total Porosity ◽  
Field Capacity ◽  
Sand Content ◽  
Wilting Point

This research was conducted to study relationship between soil moisture content and soil physical characteristics that affected the moisture.The soil samples were collected from 22 scattered sites of West Java and Central Java. Analysis of soil physical properties (texture, bulk density, particle density, total porosity and soil moisture retention) and soil chemical property (organic matter) was conducted at the laboratory of Department of Soil Sciences, Faculty of Agriculture, Bogor Agricultural University. Analysis of simple linier regression was applied to know the correlation between soil moisture content and other basic soil physical properties.Availability of soil moisture (pF 4.20 – pF 2.54) significantly correlated with organic matter, total porosity, and micro pores. The higher organic matter content as well as total porosity and micro pores the higher available soil moisture. Soil moisture of field capacity significantly correlated with clay content, sand content, micro and macro pores. The higher clay content and micro pores the higher soil moisture of field capacity. In the contrary, the higher macro pores and sand content the lower the field capacity. Soil moisture of wilting point significantly correlated with clay content and macro pores. The higher clay content the higher the wilting point, while the higher macro pores the lower soil moisture of wilting point. Keywords : Available soil water, field capacity, organic matter, soil pores, wilting point

Convective and microwave drying characteristics, energy requirement and color retention of dehydrated nettle leaves (Urtica diocia L.)

2017 ◽  
Author(s):  
Fuat Lule ◽  
Turhan Koyuncu
Keyword(s):  
Moisture Content ◽  
Air Temperature ◽  
Energy Requirement ◽  
Color Difference ◽  
Microwave Drying ◽  
Convective Drying ◽  
Drying Time ◽  
Drying Characteristics ◽  
Color Retention ◽  
Specific Energy Requirement

In this research, convective and microwave drying characteristics, energy requirement and color changes of nettle leaves (Urtica diocia L.) were reported. Samples of freshly harvested nettle leaves were dehydrated under three air temperatures of 50 °C, 60 °C and 70 °C and at three microwave power levels of PL-1, PL-2 and PL-3. Selected drying air velocity was 0.30 m/s for all temperatures. This is coming from the fact that it was understood from the preliminary studies that the temperature less than 50 °C and the air speed more than 0.30 ms-1 increase the drying time and energy requirement, extremely for these products. Nettle leaves were dehydrated from the initial moisture content of 320 (percentage dry basis) to a final moisture content of 7 % to 9 %. During convective drying experiments, product were weighted automatically by the balance per (5 to10) min. Data were transferred to the computer and processed by a software. During microwave drying, the product were weighted and data recorded manually per (15 to 60) min. The influence of drying method, drying air temperature and microwave power level have also been studied. Hunter L, a, b values system was also used to evaluate changes in total color difference (DE) on dried products. The results showed that convective drying air temperature and microwave oven power levels influenced the total drying time, total energy requirement, specific energy requirement and color difference for nettle leaves. The minimum specific energy requirement were determined as 6.95 kWhkg-1 and 23.63 kWhkg-1 for 70 °C and PL-2 respectively. 70 °C drying air temperature and PL-3 was found to yield better quality product in terms of color retention of Hunter L, a, b and DE. As a result, to reduce drying energy consumption and to keep better color retention, convective drying can be recommended for this application.

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