Journal of Agricultural Engineering 2018-07-13T09:09:12+02:00 Paola Granata Open Journal Systems <p>The<strong> Journal of Agricultural Engineering (JAE) </strong>is the official journal of the<a href=""><strong> Italian Society of Agricultural Engineering &nbsp;</strong></a>supported by University of Bologna, Italy. The subject matter covers a complete and interdisciplinary range of research in engineering for agriculture and biosystems.</p> The use of disc stack centrifuge in the virgin olive oil industry 2018-07-13T09:09:11+02:00 Giacomo Costagli The disc stack centrifuge (DSC) in the virgin olive oil (VOO) industry is widely used for oil purification at a final stage of extraction process. The obtained oil should be commercialized directly as turbid or sent to settling and/or filtration. Despite technology is strongly consolidated, few literature is available on the effect of DSC on efficiency and quality of VOO, specially compared with alternative methods. Alternative technologies to DSC like settling or direct filtration are suitable only for very small production scale. Application of advanced technology already available for DSC like hermetic design is applicable also to VOO but more research is necessary to establish effect on quality and cost/benefit ratio. Improvement of installation module and a more appropriate use of DSC on VOO industry are recommended to reduce water consumption and consequent loss of VOO quality. 2018-07-09T12:40:33+02:00 ##submission.copyrightStatement## Mechanical distribution of beneficial arthropods in greenhouse and open field: A review 2018-07-13T09:09:11+02:00 Rita Papa Giuseppe Manetto Emanuele Cerruto Sabina Failla In the last decades, political policies and collective consciousness focused on the importance of sustainable food and environmentally friendly approaches in agriculture. Distribution of beneficial organisms is a very important factor in integrated pest management, and mechanical release could improve application uniformity as well as reduce costs and working time. Several mechanisation experiences have been carried out through the years, however none of them has still found a massive application in common agricultural practices. This review paper analyses all the efforts made in this direction, by evaluating main strengths and weakness points of manually brought, tractor mounted, or aerial mechanical devices. In this way development opportunities can be identified, in a field that could achieve a substantial role in food production and agricultural activities while respecting the environment and human health. 2018-02-27T00:00:00+01:00 ##submission.copyrightStatement## Multibody model of fruit harvesting trucks: comparison with experimental data and rollover analysis 2018-07-13T09:09:11+02:00 Stefano Melzi Edoardo Sabbioni Michele Vignati Maurizio Cutini Massimo Brambilla Carlo Bisaglia Eugenio Cavallo Fruit harvesting trucks are used to easy and speed-up the work of agricultural operators. These vehicles are provided with a moving cargo bed, which can be raised up to 3 meters from the ground so that workers are closer to the plants top. Due to factors like height of centre of gravity and operation on soft and irregular soil, these vehicles present several safety issues. This research, carried out inside a project funded by INAIL (Italian National Institute for Insurance against Accidents at Work), analysed the stability of fruit harvesting trucks with particular focus on rollover risk. Experimental tests were carried out to characterise the response of these vehicles. Multibody models of two trucks were then developed and used to determine the rollover angle along a generic direction considering the effect of vehicle configuration and of tire-soil stiffness. 2018-07-09T12:40:34+02:00 ##submission.copyrightStatement## Performance evaluation of a cabinet solar dryer for drying red pepper in Bangladesh 2018-07-13T09:09:11+02:00 Muhammad Zakaria Hossain Md Masud Alam Md Faruq Bin Hossain MSH Sarker Md Abdul Awal Nusrat Jahan A cabinet type solar dryer was designed and fabricated over a collector and dryer area of 4.00 m<sup>2</sup> and 7.5 m<sup>2</sup> respectively for the geographical condition of Bangladesh. Red pepper was used to test the performance of the dryer. The upper tray and lower tray pepper drying needed 36 and 41 h to reduce moisture from 73% (wet basis) to 10% (wet basis) respectively and found 9 kg dried pepper from 30 kg fresh red ripe pepper. In contrast, open sun drying needed 85 h to reduce moisture from 73% (wet basis) to 11% (wet basis) and produced 2.43 kg dried pepper from 8 kg red ripe pepper. The average global radiation was about 133 W/m<sup>2</sup> while the flux incidence and flux absorbed on collector was about 128 W/m<sup>2</sup> and 103 W/m<sup>2</sup> respectively. The average collector and dryer efficiency was about 48% and 34% respectively. The average exergy efficiency was obtained 63%. The average rate of top, bottom and side collector loss was 37 W/m<sup>2</sup>, 20 W/m<sup>2</sup> and 3 W/m<sup>2</sup> respectively. The upper tray, lower tray and open sun pepper seed germination was 76%, 81% and 85% respectively (P≥0.01). The redness value of lower tray pepper (a*=27.1) was higher followed by upper tray (a*=24.7) and open sun pepper powder (a*=21.1), which means direct exposure of sunlight diminishes the quality of pepper colour. The redness value of fabricated solar drying was significantly (P≤0.01) higher than that of open sun drying. 2018-07-09T12:40:34+02:00 ##submission.copyrightStatement## Experimental determination of highly dynamic forces during wood trunk comminution with a drum chipper 2018-07-13T09:09:11+02:00 Philip Pichler Martin Leitner Florian Grün Christoph Guster Using large wood chips for heating systems in industrial applications is becoming popular. As a result, the requirements of the machinery that produces these large wood chips have increased, especially on the chipping tools and on the surrounding supportive components. This paper evaluates the acting main forces on a chipping drum that produces large wood chips via field and laboratory-based experimental measurements. In this study, a variety of strain gauges are applied to selected areas of the rotating chipping drum to measure localised strain conditions during wood-stem cutting. Four different wood species were investigated for comparison. Furthermore, the influence of sharp and dull knives is analysed. With the aid of experimental measurements and analysis on a laboratory scale, linear models are developed to determine the chipping force, which is cutting depth-dependent, for a variety of wood species. Testing parameters for such models are proposed via load spectra. The variability of the acting force value is evident. The maximum load on the drum affects at 10% of the time of a single cut. The largest applied forces are between 1.6 and 1.8 higher than the calculated average force. The commuting hornbeam sample exhibits the highest resistance against chipping compared to the three-other species. Additionally, a change in the load is easily recognised in the field test when utilising dull chipping blades. A reconstruction of the alternate load direction is based on laboratory testing. 2018-01-11T00:00:00+01:00 ##submission.copyrightStatement## Field studies on the soil loss reduction effectiveness of three biodegradable geotextiles 2018-07-13T09:09:12+02:00 Flavia Tauro Paolo Cornelini Salvatore Grimaldi Andrea Petroselli Biodegradable geotextiles have the potential to significantly reduce soil loss and ensure slope stability in areas at risk. Here, we focus on three biodegradable textiles (namely, jute net, jute mat, and wool mat), and study their response in terms of soil loss to diverse precipitation events (average rainfall intensity from 3.7 mmh<sup>−1</sup> to 70 mmh<sup>−1</sup> and duration from 0.5 h to 11.6 h). Experiments are conducted in an ad hoc developed outdoor steep slope (more than 60%). Soil loss reduction from the treatments is found to be very remarkable (up to 98%), thus supporting the potential of natural materials for soil conservation. Also, experimental findings confirm that the maximum intensity of rainfall events plays an important role in driving soil erosion. 2018-02-19T00:00:00+01:00 ##submission.copyrightStatement## Physical and gas permeation properties of five-layer polyethylene film used as greenhouse roof 2018-07-13T09:09:12+02:00 Abdelkader Dehbi Boulos Youssef Abdel-Hamid I. Mourad Corinne Chappey Pietro Picuno Dina Statuto The effect of sand wind ageing simulation performed under different conditions for a five-layer film consisting of polyethylene, poly-vinyl-acetate and various additives has been investigated. The mechanical properties of the five-layer films after several treatments were evaluated, together with their surface morphology - analysed by using Fourier transform infrared and contact angle - and gas permeation properties. The experimental analysis indicated that these treatments had a significant influence on the surface of the film only. An attempt has been done to compare the properties of the five-layer films with the monolayer and tri-layer films with or without air bubble under similar conditions. 2018-02-27T00:00:00+01:00 ##submission.copyrightStatement## Limiting factors for anaerobic digestion of olive mill wastewater blends under mesophilic and thermophilic conditions 2018-07-13T09:09:12+02:00 Demetrio Antonio Zema Giovanni Zappia Souraya Benalia Giuseppe Zimbalatti Enzo Perri Elena Urso Vincenzo Tamburino Bruno Bernardi Experimental trials of anaerobic digestion of olive mill wastewater (OMW) blended with other agro-industrial by-products were carried out to evaluate biogas production and sensitivity of the process to inhibiting compounds. Blends containing different percentages of OMW, digested liquid manure, and citrus peel were subjected to a batch anaerobic digestion process under both mesophilic and thermophilic conditions. The results showed that blends with percentages of OMW higher than 20% (v/v) had low methane yields due high concentrations of polyphenols (PPs) and/or volatile fatty acids (concentrations above 0.8 g kg<sup>–1</sup> and 2.4 g L<sup>–1</sup>, respectively). The addition of other substrates such as citrus peel may have induced synergic inhibiting effects of PPs and essential oils (EO) on microbial growth. Thermophilic processes were more sensitive to these inhibiting compounds than mesophilic processes. The results of this study suggest that reducing PPs and EO concentrations in blends subject to anaerobic digestion below the inhibiting concentrations of 0.6 g L<sup>–1</sup> and 0.5 g kg<sup>–1</sup>, respectively, is suitable. Additionally, it is advisable to maintain the volatile fatty acids content below 2 g L<sup>–1</sup> to avoid its evident toxic effects on the growth of microorganisms in biochemical processes. 2018-02-19T00:00:00+01:00 ##submission.copyrightStatement##