Revista Engenharia na Agricultura - Reveng

Quality of soy bean grain stored in bag silo

2020-12-10T15:16:25-03:00

Because of the rise in the use of bag silo in the last harvests due to the lack of static capacity in Brazil, the storage of grain in type of structure is currently seen as a solution to our storage deficit. Thus, the importance of maintaining the quality of grains for commercialization in these systems is considered. The objective of this experiment was to evaluate the quality of soybean grain stored in a silo bag, in the region of Dourados, State of Mato Grosso do Sul, Brazilian Central-West. The experiment was carried out in a cooperative, where soybean grain stored in silo bag are collected. The product had been received, processed at the end of the summer harvest and previously stored in metallic silos, and then transferred to the silo bags upon reception of the winter harvest. Thus, soybeans with an average water content of 11% w.b. were packed in bags composed of high-density polyethylene and hermetically sealed over a total period of 125 days, with collections of data on temperature and air relative humidity and grain sampling every 40 days. The collected samples were subjected to plant classification and analyses of water content, water activity, protein, lipids and color parameters were also performed. Na average rise of 5° C was observed in the temperature and 14% for air relative humidity which resulted in the of moldy and fermented grains after 125 days in the bags. The storage period factor was significant (p <0.05) in the variables of water content, color and oil. It was concluded that for soybeans the storage period in hermetic bags influences the quality of the grains and the internal environmental conditions in these structures are influenced by the convective microcurrents observed in the different positions inside the silo bag.

Physiological quality of mechanically harvested chickpea seeds

2021-01-08T11:20:04-03:00

Our objective was to evaluate the occurrence of mechanical damage in chickpea seeds with the combination of two harvester speeds (2.5 and 3.5 km.h-1) and three adjustments for rotor rotation speeds (500, 700, and 850 rpm). Harvesting was carried out in a seed production field. Seeds were evaluated for purity, germination (G), first count (FC), germination speed index (GSI), hypochlorite, electrical conductivity, and tetrazolium tests. There was an effect of harvester speeds on seed physiological quality for the first count (FC), germination (G), germination speed index (GSI), especially when combining with high rotor rotation speed. In these cases, the speed of 2.5 km.h-1 resulted in lower values. This harvester speed also had worse results when combining with 850 rpm for purity and hypochlorite tests. The tetrazolium test was not efficient in identifying differences in seed quality. There was no significant interaction between harvester speeds and rotor rotation speeds for the conductivity test. Evaluating the harvester speed’s isolated effect (3.5 km.h-1), we identified problems in seed vigor due to the higher value of exudates in the electrical conductivity test. Low harvester speed (2.5 km.h-1) associated with high rotor rotation speeds (700 and 850 rpm) causes a reduction of the physical and physiological quality of seeds.

Performance of hydraulic ram built with different volumes of air chamber

2020-10-14T01:46:04-03:00

To capture surface water and groundwater, in most cases, electrical or fuel energy is required to drive a motor pump. This work aims to evaluate and compare the hydraulic characteristics of a hydraulic ram built with different volumes of PVC air chambers, according to its efficiency and economy. The study was developed at the Federal Rural University of the Amazon. Calibrated tanks and a stopwatch were used to obtain the supply flow, wasted water and repression volume. Four treatments were performed with 25% (125 L), 50% (250 L), 75% (375 L) and 100% (500 L) of raw material. For treatments with different volumes of air chambers, PVC tubes of 10, 20, 30, 40 and 50 cm in length were used. The experiment was a completely randomized design, carrying out the analysis of variance, Pearson correlation coefficient and the Tukey test for comparison among averages. There is a strong tendency to increase the repression volume and wasted when the volume of the air chamber is increased. The 0.250 L air chamber presented relevant results. In addition, it was demonstrated that with the increase in the volume of the air chamber, there was an increase in performance.

Evaluation of the performance of covered lagoon digester in terms of the solids loading

2020-12-18T19:17:27-03:00

The use of anaerobic digesters to convert residual biomass for energy use and nutrient recovery has been increasingly indicated by the operational simplicity and added value of the treatment by-products. However, the levels of solids present in the influents to be treated directly influence the operation and management of the system. Thus, the objective of the study was to evaluate the performance of covered lagoon digesters in terms of the solids loading in the swine wastewater treatment system. The study was performed in a farm located in Zona da Mata Mineira. The monitoring took place from September 2018 to August 2019. The influent flow of waste was estimated based on the analysis of monthly water consumption on the farm. The collection and sampling took place weekly, the influents and effuents were analyzed in terms of the solids loading of total solids (TS) and volatiles solids (VS). The mean total flow distributed to the two digesters was 102.3 m³.d-1, with a mean hydraulic retention time (HRT) of 24.5 days. The results ranged from 1.14 to 2.83% for TS at the start of treatment. In most of the monitored months, anaerobic digesters were being fed with organic overload in terms of VS, which consequently affected the efficiency of the system, which were 33.6% for TS and 39.5% for VS.