The objective of this study was to optimize the mechanical oil extraction of Jatropha curcas seed... more The objective of this study was to optimize the mechanical oil extraction of Jatropha curcas seeds by increasing the efficiency of oil recovery and decreasing oil residues in press cake. The experiments were carried out with mechanical screw press type – Komet D85-1G. Four setups were created by parameter combination of two different screws (16 and 21.5 mm choke ring size), with two different press cylinders (1 and 1.5 mm bore size), three different nozzles (8, 10 and 12 mm nozzle diameter) and three rotational speeds (low, medium and high). Oil recovery reduced when rotational speed increases for all setups; highest oil was 89.4% (m/m). The oil recovery was increasing when energy input increased and decreasing when seed material throughput increased. The relations between energy input and seed material throughput followed a strict pattern, which correlated with oil recovery. This correlation can be used for determining the optimal operation parameters.
In many developing countries biomass is used as main source of energy. Cultivation of Jatropha cu... more In many developing countries biomass is used as main source of energy. Cultivation of Jatropha curcas L. can generate income and employment by producing oil and by-products. Residues generated during processing of J. curcas fruits such as fruit sheaths, seed shells and press cake residues are large potential of biomass energy sources. The object of this study was to determine the fuel properties of seed shells and press cake and monitor the combustion performance of J. curcas seed shell and press cake residues in a tilting furnace with bowl burner that was designed at Universität Hohenheim. During combustion feeding rate and air mass flow were varied in order to determine combustion performance. Temperature of flame, burning chamber and flue gas were monitored. Flue gas emissions such as CO 2 and CO were measured. For combustion of seed shells and press cake an optimum feeding rate of 30 kg/h and 15 kg/h was found, respectively. The CO 2 emissions ranged from 3 to 5 Vol. % for all e...
At the Universität Hohenheim (Stuttgart, Germany) a plant oil pressure stove 'Protos' was... more At the Universität Hohenheim (Stuttgart, Germany) a plant oil pressure stove 'Protos' was developed in cooperation with Bosch und Siemens Hausgeräte GmbH (Munich, Germany). The stove shows satisfactory performance and reliability; however, combustion deposits are formed inside the vaporizer when using plant oil as fuel. The objective of this study was to investigate the influence of total contamination content of J .curcas oil on the technical performance and formation of deposits in the plant oil pressure stove. Four test fuels with 55, 116, 638 and 1126 mg/kg of total contamination content were prepared. Combustion trials were carried out in three replicates. The results show lowest deposits for test fuel with 55 and 116 mg/kg contamination resulting in 1.46 and 1.42 g deposits per kg of consumed oil. A positive correlation between deposits and total contamination was found. Consumption of J. curcas oil was ranging from 0. 21 to 0.29 kg/h according increasing total contami...
Due to the climate change and decreasing water availability in many parts of the world, water eff... more Due to the climate change and decreasing water availability in many parts of the world, water efficient irrigation becomes more and more important to stabilize or even increase agricultural productivity. An efficient irrigation scheduling relies on soil water potential information in order to define the optimal irrigation start as well as on soil water content data to quantify the amount of soil water and thus to properly define irrigation depth. Furthermore, nutrient leaching and groundwater contamination will be reduced by controlled irrigation. Therefore, a novel dual soil sensor was developed which allows for simultaneous determination of water content and water potential at low costs suitable for distributed sensing. The soil water content measurement is realized with a dielectric measurement approach. Sensor elements are arranged on a printed circuit board, which can easily be inserted into the soil. Soil water potential data is deduced from water content measurements in porou...
Against the background of climate change and decreasing water availability in many parts of the w... more Against the background of climate change and decreasing water availability in many parts of the world, there is the need for soil moisture information to improve water efficiency in agricultural irrigation. This study presents a newly developed sensor, which measures simultaneously soil water content and correlated soil water potential. Water content is measured based on a dielectric approach (FDR, frequency domain reflectometry). Soil water potential data is obtained by water content measurements in two porous matrices. First results show precise soil permittivity measurements from which soil water content data can be deduced. Water content measurements within the matrices are robust without noise. Soil water potential within the important range for irrigation can be properly assessed with selected matrices. Together with a controller that interacts between sensor and customary irrigation control, optimal irrigation automation becomes possible.
The objective of this study was to optimize the mechanical oil extraction of Jatropha curcas seed... more The objective of this study was to optimize the mechanical oil extraction of Jatropha curcas seeds by increasing the efficiency of oil recovery and decreasing oil residues in press cake. The experiments were carried out with mechanical screw press type – Komet D85-1G. Four setups were created by parameter combination of two different screws (16 and 21.5 mm choke ring size), with two different press cylinders (1 and 1.5 mm bore size), three different nozzles (8, 10 and 12 mm nozzle diameter) and three rotational speeds (low, medium and high). Oil recovery reduced when rotational speed increases for all setups; highest oil was 89.4% (m/m). The oil recovery was increasing when energy input increased and decreasing when seed material throughput increased. The relations between energy input and seed material throughput followed a strict pattern, which correlated with oil recovery. This correlation can be used for determining the optimal operation parameters.
In many developing countries biomass is used as main source of energy. Cultivation of Jatropha cu... more In many developing countries biomass is used as main source of energy. Cultivation of Jatropha curcas L. can generate income and employment by producing oil and by-products. Residues generated during processing of J. curcas fruits such as fruit sheaths, seed shells and press cake residues are large potential of biomass energy sources. The object of this study was to determine the fuel properties of seed shells and press cake and monitor the combustion performance of J. curcas seed shell and press cake residues in a tilting furnace with bowl burner that was designed at Universität Hohenheim. During combustion feeding rate and air mass flow were varied in order to determine combustion performance. Temperature of flame, burning chamber and flue gas were monitored. Flue gas emissions such as CO 2 and CO were measured. For combustion of seed shells and press cake an optimum feeding rate of 30 kg/h and 15 kg/h was found, respectively. The CO 2 emissions ranged from 3 to 5 Vol. % for all e...
At the Universität Hohenheim (Stuttgart, Germany) a plant oil pressure stove 'Protos' was... more At the Universität Hohenheim (Stuttgart, Germany) a plant oil pressure stove 'Protos' was developed in cooperation with Bosch und Siemens Hausgeräte GmbH (Munich, Germany). The stove shows satisfactory performance and reliability; however, combustion deposits are formed inside the vaporizer when using plant oil as fuel. The objective of this study was to investigate the influence of total contamination content of J .curcas oil on the technical performance and formation of deposits in the plant oil pressure stove. Four test fuels with 55, 116, 638 and 1126 mg/kg of total contamination content were prepared. Combustion trials were carried out in three replicates. The results show lowest deposits for test fuel with 55 and 116 mg/kg contamination resulting in 1.46 and 1.42 g deposits per kg of consumed oil. A positive correlation between deposits and total contamination was found. Consumption of J. curcas oil was ranging from 0. 21 to 0.29 kg/h according increasing total contami...
Due to the climate change and decreasing water availability in many parts of the world, water eff... more Due to the climate change and decreasing water availability in many parts of the world, water efficient irrigation becomes more and more important to stabilize or even increase agricultural productivity. An efficient irrigation scheduling relies on soil water potential information in order to define the optimal irrigation start as well as on soil water content data to quantify the amount of soil water and thus to properly define irrigation depth. Furthermore, nutrient leaching and groundwater contamination will be reduced by controlled irrigation. Therefore, a novel dual soil sensor was developed which allows for simultaneous determination of water content and water potential at low costs suitable for distributed sensing. The soil water content measurement is realized with a dielectric measurement approach. Sensor elements are arranged on a printed circuit board, which can easily be inserted into the soil. Soil water potential data is deduced from water content measurements in porou...
Against the background of climate change and decreasing water availability in many parts of the w... more Against the background of climate change and decreasing water availability in many parts of the world, there is the need for soil moisture information to improve water efficiency in agricultural irrigation. This study presents a newly developed sensor, which measures simultaneously soil water content and correlated soil water potential. Water content is measured based on a dielectric approach (FDR, frequency domain reflectometry). Soil water potential data is obtained by water content measurements in two porous matrices. First results show precise soil permittivity measurements from which soil water content data can be deduced. Water content measurements within the matrices are robust without noise. Soil water potential within the important range for irrigation can be properly assessed with selected matrices. Together with a controller that interacts between sensor and customary irrigation control, optimal irrigation automation becomes possible.
Uploads
Papers by Shkelqim Karaj