Research in Agricultural Engineering, 2020 (vol. 66), issue 2

Influence of magnetised irrigation water on the fertigation process and potato productivityOriginal Paper

Harby Mostafa

Res. Agr. Eng., 2020, 66(2):43-51 | DOI: 10.17221/1/2020-RAE  

An experiment was conducted for two seasons on a farm in the Mit Kenana village, Qalyobia, Egypt. The aim was to study the influence of a magnetised water technology on the fertilisers during irrigation (fertigation) and its impact on the water, soil as well as the yield and yield components for potatoes. The experiment included: Normal water (NM), magnetic water (MW), adding fertiliser before (FMW) and after magnetism (MWF). The results indicated that irrigation with magnetised water and then adding fertiliser (MWF) had a positive significant effect on the water and soil properties, the tuber engineering parameters improved and the potato productivity...

Uncertainty estimation of the mean specific heat capacity for the major gases contained in biogasOriginal Paper

P. Trávníček, I. Vitázek

Res. Agr. Eng., 2020, 66(2):52-59 | DOI: 10.17221/4/2020-RAE  

The paper is focused on the uncertainty estimation of the mean isobaric and isochoric specific heat capacity calculation. The differences in the data among the individual sources for the technical calculation are presented in the first part of the paper. These differences are discussed in this paper. Research of scientific work with listed values of measurement uncertainties has been carried out in the second part of the paper. Furthermore, mathematical models were calculated which describe the dependence of the specific heat capacities and temperature. The maximal error models were carried out. Two approaches were used for the calculation of the mean...

Evaluation of the stress state of a cultivator blade in production and operationOriginal Paper

Tamara Skoblo, Ivan Rybalko, Aleksandr Tihonov, Taras Maltsev

Res. Agr. Eng., 2020, 66(2):60-65 | DOI: 10.17221/8/2020-RAE  

The aim of the work was to determine the quality of a new and used cultivator blade to assess the condition of the metal with the development of rejection norms of its variability in a magnetic parameter - coercive force using various types of equipment - coercimeters. The new cultivator blade shows the highest level of coercive force that is characteristic of its right and left parts and its decrease occurs towards the toe. After operation, variability is noted, characterised by both an increase and a decrease in the indicators of the coercive force. Rejection norms of the metal state, which determine the possibility of restoring a worn cultivator...

Effectiveness of an evaporative charcoal cooler for the postharvest preservation of tomatoes and kalesOriginal Paper

Erick Kiplangat Ronoh, Christopher Luchebeleli Kanali, Samuel Njuguna Ndirangu

Res. Agr. Eng., 2020, 66(2):66-71 | DOI: 10.17221/52/2019-RAE  

The preservation of fresh produce can provide rural households with better diets all-year round and income by reducing their deterioration. Promotion of low-cost temporary storage technologies requires evidence of their effectiveness to attain conducive conditions. Therefore, this study was conducted to assess the effectiveness of an evaporative charcoal cooler for the preservation of tomatoes and kales. The cooler microclimate and outdoor conditions were investigated by measuring the air temperature and relative humidity. During the study period, the maximum temperature difference between the cooler and the outdoors was found to be 9.2 °C while...

Assessment of a submerged membrane bioreactor with composite ceramic filters for cassava wastewater treatmentOriginal Paper

Nurudeen Samuel Lawal, Kolawole Ogedengbe, Olukayode Omotayo Smith Ojo, Abubakre Adeyanju Odufowokan

Res. Agr. Eng., 2020, 66(2):72-79 | DOI: 10.17221/109/2018-RAE  

Cassava processing activity is characterised by the generation of an enormous quantity of toxic wastewater with detrimental effects on the environment if disposed of without adequate treatment. To alleviate this concern, lab-scaled cylindrical-shaped composite ceramic filters produced from rice husk and clay mixed with equal proportions of activated carbon, kaolin and sherd powder were produced and assessed in a membrane bioreactor. The permeate obtained from the filter with 2.39% rice husks, 0.95% activated carbon, 0.80% kaolin, 0.40% sherd powder and 95.47% clay gave the optimum pollutant removal efficiency. The average removal efficiencies of the...