Plant Nutrition, Soil Fertility and Fertilizers
Narges Sousaraei; Mojtaba Barani Motlagh; Seyed Alireza Movahedi Naeini
Abstract
Introduction: When the supply of micronutrients needed by the plant is insufficient, not only the yield of the product but also the quality of plant products are affected. Application of organic amendments is one of the ways to increase the nutrients such as zinc uptake by plants for. Biochar can be ...
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Introduction: When the supply of micronutrients needed by the plant is insufficient, not only the yield of the product but also the quality of plant products are affected. Application of organic amendments is one of the ways to increase the nutrients such as zinc uptake by plants for. Biochar can be used as a raw material for the preparation and synthesis of mineral or metal composites due to its high specific surface area, porous structure and oxygen bonding groups on its surface. In these composites, biochar is used as a good porous structure to support and host metals. Biochar can have a significant impact on soil properties, the availability of nutrients, and the dynamics of the nutrients in arid and semi-arid soils, Depending on the feedstock and pyrolysis conditions However, very limited studies have examined biochar use as a nutrient carrier in the synthesis of organic-mineral compounds. Therefore, the present study was done to investigate the efficiency of zinc-enriched biochar pellets using two pre-pyrolysis and post- pyrolysis methods, and their effect on some physiological traits (chlorophyll a, b and total) and bioavailability of zinc in soil and plant.Materials and Methods: A zinc deficiency Soil was collected from 0-30 cm depth under arable lands of Seyed Abad located in Azadshahr township, Golestan Province, Iran. To achieve the objectives of this study, a factorial experiment in a completely randomized design with three replications and 18 treatments (54 pots in total) was performed in the greenhouse of Gorgan University of Agricultural Sciences and Natural Resources. Factors included three types of zinc fertilizers (zinc sulphate, zinc-rich biochar prepared using pre-pyrolysis and post-pyrolysis methods) in three levels (0, 10 and 20 mg kg-1 zinc) and foliar spraying (distilled water and 3:1000 zinc). Zinc foliar spraying was done during the 6-10 leaf stage in the early hours of the morning before sunrise. Irrigation and weeding operations were performed manually. At the end of the growing period (vegetative and reproductive), some physiological traits (chlorophyll a, b, total and carotenoid), concentration and zinc uptake in shoots in the two stages of flag leaf emergence and seed maturity, and available concentration of zinc in the soil after wheat plant harvest were measured. The statistical results of the data were analyzed using SAS software and LSD test (at 5% level) was used for comparing the mean values.Results and Discussion: Based on the results, the interaction of type and levels of treatments was significant on all the studied traits at P<0.01, except for carotenoid. The means comparison showed that both zinc-enriched biochar pellets and zinc sulfate increased physiological traits in wheat plants. The highest amount of chlorophyll a, b, and total was obtained with an average of 4.99, 3.36, and 8.35 mg g-1 of fresh weight of the plant from the treatment of a pre-pyrolysis pellet with a concentration of 20 mg kg-1 with zinc sulfate foliar spraying, respectively. The highest zinc uptake in both the flag leaf emergence and seed maturity stages was obtained with an average of 120.33 and 86.62 mg kg-1 of dry weight of the plant from the pre and post-pyrolysis pellet treatment with a concentration of 20 mg/kkg with zinc sulfate foliar spraying, which had an increase of 20 mg kg-1 of zinc sulfate foliar spraying, respectively, equivalent to 27.69 and 30%. The pre-pyrolysis pellet treatment with 20 mg kg-1 zinc and zinc sulfate foliar spraying gave the most zinc extracted with DTPA, at an average of 3.41 mg kg-1. This was compared to the 10 mg kg-1 and 0 mg kg-1 pre-pyrolysis biochar pellet treatments, which gave an average of 2.39 mg kg-1 and 0.92 mg kg-1, respectively, which is an increase of 29.91 and 73.02 percent. The amount of DTPA extractable Zn with the amount of chlorophyll a (r = 0.87**), chlorophyll b (r = 0.81**), total chlorophyll (r = 0.87**), and carotenoids (r = 0.89**) had a positive and significant correlation. The results showed that between DTPA extractable Zn with zinc concentration (r = 0.91**) and zinc uptake (r = 0.90**) in the stage of flag emergence and zinc concentration (r = 0.87**) and zinc uptake (r = 0.86**) in the stage of seed maturity in the wheat plant, there was a positive and significant correlation.Conclusions: In general, the results showed that the positive role of biochar-zinc pellets in increasing the concentration and zinc uptake in wheat plants. Nevertheless, supplemental zinc foliar application with biochar pellets rich in zinc in the amount of 20 mg kg-1 in the form of post-pyrolysis had the greatest effect on the physiological characteristics and Zn bioavailability for wheat plants.
Post Harvesting Technology
Reza Tabatabaeekoloor; shaban ghavami jolandan
Abstract
Introduction: Fuel pellets are one of the uses of biomass, which are made from agricultural waste, plant residue, and animal excrement. They produce more energy per unit volume. Various factors are effective in the pelleting process. Having information about them helps to optimize the pelleting process ...
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Introduction: Fuel pellets are one of the uses of biomass, which are made from agricultural waste, plant residue, and animal excrement. They produce more energy per unit volume. Various factors are effective in the pelleting process. Having information about them helps to optimize the pelleting process and to understand the compression mechanism and the design of compacting equipment. Materials and Methods: Olive pomace raw material for making pellets was obtained from an olive processing factory in Rudbar city in Gilan province. The prepared materials were transferred to the laboratory in the necessary amount in nylon bags and dried in the oven at 105 degrees Celsius for 24 hours. The dried samples were powdered by a laboratory grinder and then passed through sieves in the range of 0.6-1.5 mm and used to make pellets. Before making pellets, the initial moisture content of the samples was obtained using the drying method. First, pre-tests were conducted to make pellets and the moldability and strength of the samples were checked. A palletization mechanism was used to compress the pellet. This system was designed and built in biosystem mechanics of Sari University of Agricultural Sciences and Natural Resources. The material was placed inside a steel mold with a cylinder inner diameter of 8.05 mm and a height of 150 mm with a blocked end. A piston with a diameter of 8 mm connected to the driving arm of the tension-compression test machine was used to compress the material. Loading by a piston with a quasi-static speed of 6 mm per minute is compressed. In this research, the effect of particle size treatments (600-900, 900-1200 and 1200-1500 μm), compaction pressure (75, 150 and 225 MPa) and temperature (50, 70 and 90 ͦC) on the density, strength and durability of the pellet were investigated.Results and Discussion: The results indicated that the main effects of all three mentioned treatments on the strength, density and durability of the pellet are significant. Also, the mutual effects of some treatments are also significant on these characteristics. The interaction effect of particle size and compaction pressure on pellet compressive strength is significant at 5% level. With the increase in particle size, the pellet strength increased first, and then with the further increase in particle size, the pellet strength decreased slightly. On the other hand, with the increase in compression pressure, the pellet resistance increased. Pellet density is an important factor for storage and transportation as well as combustion efficiency. The mutual effect of compression pressure and particle size on pellet density is significant. Changes in pellet density were obtained in the range of 1.015 to 1.350 grams per cubic centimeter. The usual and recommended density for pellets made from agricultural and forest residues should be more than 0.8 grams per cubic centimeter. The interaction effect of compaction pressure and temperature on pellet durability is significant. The range of durability changes for pellets is between 81 and 95 percent. Increasing compaction pressure significantly improved the stability of the pellets, which indicates the role of compaction in bonding between particles and creating bridges for greater particle strength. The highest pellet strength was obtained in the combination of particle size of 900-1200 micrometers, temperature of 90 degrees Celsius and compaction pressure of 225 MPa. The highest density was obtained at a particle size of 600-900 and a compression pressure of 225 MPa and the best stability at a compression pressure of 150 MPa and a temperature of 90 degrees Celsius. In general, the physical and mechanical properties of the pellet were affected by all three factors: particle size, temperature and compaction pressure.Conclusion: The results of this research showed that all three factors of particle size, compaction pressure and temperature have a significant effect on the physical and mechanical properties of pellets such as density, strength and durability. Choosing the right particle size plays an important role in making the pellet stronger. The temperature of the die during pelleting is also very important in the bonding of the pellet particles because at the right temperature, the bonding between the bridges strengthens the connection of the particles and as a result increases the strength and durability of the pellet. In general, the results of the research showed that to make pellets from olive processing factory waste, a suitable combination of particle size parameters, compaction pressure and die temperature is needed to make pellets with high strength and durability.
Energy and Renewable Energies
Ahmadreza Abdollahpour; Reza Tabatabaee; Jafar Hashemi
Abstract
Introduction: Agricultural residues and wastes are the main source of biomass for use in bioenergy production and animal and poultry feed production industries. These biomasses in their original form have a large volume and low energy (per unit volume) and require a lot of space and extensive movement. ...
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Introduction: Agricultural residues and wastes are the main source of biomass for use in bioenergy production and animal and poultry feed production industries. These biomasses in their original form have a large volume and low energy (per unit volume) and require a lot of space and extensive movement. Therefore, one of the methods of optimal use of these biomasses is to transform them into pellets, which have more mass and energy per unit volume and enable their easier use and transportation. Currently, biomass has the fourth place in energy supply after oil, natural gas and coal and provides approximately 14% of the world's energy needs. The use of biomass, especially in European Union countries, as an attractive source for replacing fossil fuels is developing and expanding. The use of biomass as fuel has significantly reduced the amount of environmental pollutants, so that the amount of CO2 absorbed from the atmosphere during biomass growth is similar to the amount produced during combustion, followed by a net cycle of production. Materials and Methods: The raw materials for making pellets were prepared from spruce wood sawdust (collected from a sawmill in Sari) as well as corn stalk and soybean residues in the fields of Dasht Naz in Sari. The desired materials were transferred to the laboratory in the necessary amount and kept at ambient temperature until the experiments. The samples were first crushed into 20 mm sizes and then powdered using a grain mill (Mehr Tehiz company, Iran) and passed through 18 mesh sieves in the range of 1 mm to make pellets. A palletization mechanism was used to compress the pellet. This system was designed and built in biosystem mechanics of Sari University of Agricultural Sciences and Natural Resources. The material was placed inside a steel mold with a cylinder inner diameter of 8.05 mm and a height of 150 mm with a blocked end. A piston with a diameter of 8 mm connected to the driving arm of the tension-compression test machine was used to compress the material. Loading by a piston with a quasi-static speed of 5 mm per minute is compressed to a pressure of 1300 N.Results and Discussion: In this research, the mechanical and thermal properties of pellets made from the combination of spruce sawdust and corn and soybean residues were evaluated. In the present study, the effect of four combinations of agricultural and forest materials at two moisture levels (12% and 18% based on fresh weight) on the indices of density, compressibility, Hausner ratio, strength and calorific value of the produced pellets were investigated and evaluated. it placed. The results showed that the pellet density at 18% humidity was lower than the density at 12% humidity. The highest density related to the combination of 60% spruce wood sawdust-40% corn stalks was obtained with a value of about 149 kg/m3 and the lowest value related to 100% soybean stalks was about 110 kg/m3. Also, the ratio of Hanser and CI in the combined pellets that have a higher percentage of sawdust and also in the combination of sawdust with corn stalks are within the permissible range. The highest pellet strength was 23.8 N/cm corresponding to 100% sawdust at 18% humidity and the lowest was 15.4 N/cm corresponding to 100% soybean stalk at 12% humidity. The calorific value of the pellets is in the range of 14.37 to 18.52 MJ/kg, which is the minimum value for the pellet made from 100% soybean stalk at 18% humidity and the maximum value for the pellet made from 100% fir wood sawdust and It was obtained at a humidity of 12%. Therefore, the use of agricultural wastes and their proper combination is a good option for the production of biofuels due to their density and strength.Conclusion: The type of biological waste and moisture percentage affect the physical and mechanical properties of the produced pellets. In general, the combination of spruce wood sawdust with corn stalks and soybean improved the mechanical and thermal properties of the pellet. Hanser's ratio and compressibility in the combined pellets that have a higher percentage of sawdust and also in the combination of sawdust with corn stalks are within the standard range. Also, in the compositions that have a higher proportion of spruce wood sawdust and lower moisture, the density and strength factors of the pellet increase. The highest and lowest calorific values were obtained in a higher ratio of sawdust and a higher ratio of corn, respectively. Therefore, it is possible to make pellets from the waste of garden and agricultural products that have good density and strength and high calorific value.
