RU2796359C1 - Method for drying breeder soybean seeds and device for its implementation - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: invention is related to drying equipment, and can be applied by agricultural institutions engaged for selection and seed production. The method includes placing the seeds in fabric bags, blowing them from two opposite sides with a heat carrier with a temperature of 45±2°C, control of the relative humidity of the coolant. When the relative humidity of the coolant reaches 55%, the process of exchanging the coolant with the surrounding air is carried out for 4 minutes every 30 minutes of drying the seeds in cycles until relative humidity of the coolant of 27% is stable for 1-2 hours, after which the process of cooling the seeds is carried out by blowing the bags with seeds in ambient air to ambient temperature. The device contains two identical sections connected by a common partition. Each section includes an air chamber in form of a rectangular parallelepiped, three drying compartments, three doors, a heat generator, a fan, a coolant supply diffuser, a distributor cone, three vertical air corridors, each of which is formed by one of the walls of the air chamber and a door of the drying compartment, an exhaust duct, heat exchange damper, air duct to return coolant to the heat generator, angular adapter, air inflow damper, coolant return damper, interlocked damper and damper drives using a cable system, coolant temperature and humidity sensors, control panel, microprocessor, and each drying compartment includes a bin installed in the air corridor at the same distance from the wall of the air chamber and from the door for placing bags with seeds in it, the back side of the bin is made in form of a frame with a system of vertical rods made of profiled rolled products, and the front side is made in form of a frame with horizontally located folding loading and unloading lattice windows mounted on rails fixed on the frame.

EFFECT: group of inventions provides a drying environment that prevents cracking of seeds and preserves their selective qualities.

2 cl, 8 dwg, 1 ex

Description

SUBSTANCE: group of inventions relates to agriculture, namely to drying equipment, and can be applied in agricultural establishments engaged in selection and seed-growing activities.

Drying is one of the most important seed conservation measures. The drying process of seeds consists in the transfer of moisture by them to a drying agent, which can absorb moisture only in vapor form. Therefore, the necessary conditions for drying are the evaporation of water in the seeds and a higher water vapor pressure in the seeds than in the drying agent. Each culture has its own characteristics of drying. So, due to the high protein content, legumes do not give off water well, dry unevenly, which causes cracking of the shell, because. when drying legumes, their surface quickly dehydrates, and the central part of the seeds remains moist. Soy is a very interesting, capricious and complex crop. Soybean seeds must be dried so that the rate of evaporation of moisture from the surface of the grain does not exceed the rate of movement of moisture from the center of the grain to its surface, otherwise cracking of the grains will follow, because its seeds slowly release moisture (0.3-0.5% / hour) and very easily damaged by mechanical impact. The shell of the soybean dries out faster than the kernel with the cotyledons and germ, decreases in volume, and is easy to break under the pressure of the still wet kernel. And breeding soybean seeds should not even have microcracks on the shell at all. The maximum drying temperature for them is not higher than 45°C. Even at this temperature, soybeans can crack if the required % moisture removal per pass is exceeded. Soybean seeds are considered dry with a moisture content not higher than 12%, and for breeding seeds - not lower than 12-14%, so as not to "kill" the germ in the seed.

The prior art method of drying sunflower seeds by blowing the seeds with air while maintaining the temperature of the seeds 65-75°C to obtain a final moisture content of 7.0-7.5%. Blowing is carried out in two stages: at the first - at an air temperature of 500-600 ° C for 25-30 seconds, and at the second - at an air temperature of 100-175 ° C until the final humidity is obtained (A.S. USSR No. 1007635, A23B 9/00, F26B 3/02).

The disadvantage of this method is the inefficiency for drying soybean seeds.

A known method of drying sunflower seeds, which is an improvement of the invention according to AS. No. 1007635 and including three stages of drying: at the first stage, the seeds are heated to a temperature of 65-75°C for 25-30 seconds in a stream of hot air with a temperature of 500-600°C. Then it is dried to a final moisture content of 7-7.5% at a temperature of 100-175°C and cooled with cold air at a temperature of 10-15°C in a fluidized state with a cooling rate of 0.6-0.7°C to ambient temperature (a .s USSR No. 1512549, A23V 9/00, A26V 3/02).

The disadvantage of this method is the inefficiency for drying soybean seeds.

A known method of drying granular-fibrous materials, mainly cotton seeds and soybeans, including blowing a layer of seeds for 5 minutes with a hot coolant with a temperature of 105-110 ° C at a material fluidization number of 0.4-0.8, providing an increase in the volume of the layer by 1, 1-1.7 times relative to the original, with a layer porosity of 0.6 - 0.85 to a final moisture content of 7-10% (A.S. USSR No. 1696823, F26B 17/10).

The disadvantage of this method is the inefficiency for drying breeding soybean seeds.

A known method of drying seeds of grain crops, including passing them through a layer of a drying agent, which is used as an ozone-air mixture, with an ozone concentration in the ozone-air mixture of 2-10 mg/cm ³ (AS USSR No. 1095899, A01F 25/08).

The disadvantage of this method is the inefficiency for drying breeding soybean seeds, because. passing a drying agent through a layer of seeds, and even more so with the use of ozone, which intensifies the drying process, leads to a sharp uneven drying of seeds, to shrinkage and cracking of soybean grains due to the “rapid” removal of moisture per pass.

From the prior art, a plant for heat treatment of bulk materials - sunflower seeds, soybeans and other crops, containing series-connected chambers of a clamped fluidized bed with a gas distribution grate, a gas duct and an unloading chute, and placed between the chambers hoppers for depositing material, with the grate of each chamber above the chute has a window communicating the over-lattice zone with a box to form a separation zone (AS USSR No. 709933, F26B 17/10).

The disadvantage of this installation is its bulkiness and seed injury, which is unacceptable for breeding material.

Known chamber dryer - for drying cereals, legumes, oilseeds and other crops, containing a drying chamber, a slatted bottom with a cross-section in the form of a triangle with its apex up, and placed under the bottom of the air distribution channel, and above the bottom - guide elements made in the form a two-section grid, the lower section of which has the shape of a bottom and is located from it with a gap, and the upper section is installed at an angle to the bottom with the formation of an extension towards the top of the bottom. In addition, there is a corrective device in the upper part of the chamber, a guide pipe, an air inlet pipe, an air heater, a reflector screen, unloading valves, and other elements. (A.S. USSR No. 761801, F26B 9/06).

The disadvantage of this dryer is the complexity of the design and inefficiency for breeding soybean seeds.

Known chamber dryer for heat-sensitive materials - legumes, grains, oil seeds, corn cobs, containing chambers with sections for loading and unloading material and a distribution corridor divided into compartments connected through valves to the combustion unit, connected in turn to the collection chamber of the spent coolant and the collector , between which a branch pipe is installed that communicates with the atmosphere, the collector is equipped with gates and throttle valves and is connected to the windows of the furnace block, and pipelines for air suction are connected from the sections for loading and unloading material to the windows of the furnace block (A.S. USSR No. 956940, F26B 9 /06).

The disadvantage of the known dryer is the complexity of the design and its inefficiency for breeding soybean seeds.

Known chamber dryer for agricultural products - corn on the cob, leguminous crops and oilseeds, containing two rows of chambers with sloping ventilated bottoms, upper and lower coolant supply windows, blocked by rotary valves, loading and unloading hatches and a distribution corridor for the coolant connected to end walls of each row of chambers and divided by vertical partitions into a central compartment with on-off valves for fresh and exhaust coolant and two side compartments with multi-position double-sided valves for alternately connecting the compartments to the heat generator and the atmosphere (A.S. No. 1015207, F26B 9/06).

The disadvantage of this dryer is the complexity of the design and injury to the seeds, because. the dried material is unloaded from the chambers through hatches, and then reloaded through other hatches for alternately connecting the compartments to the heat generator and the atmosphere.

Known dryer for cereals and leguminous crops, including a drying chamber, an air duct for a drying agent, a loading and unloading device, a gas distribution grate, a diaphragm installed above the grate, consisting of two parts, one of which is movable in a horizontal and vertical plane, and an unloading the device is located between the diaphragm and the gas distribution grille. The grain passes through the open holes of the diaphragm and fills the space between it and the gas distribution grate, under which the drying agent of the required temperature is supplied by the fan. After the grain acquires the required final moisture, the movable part of the diaphragm moves and closes its holes, while the unloading device opens (AS USSR No. 1161800, F26B 9/06).

The disadvantage of this dryer is seed injury.

Known chamber dryer for dispersed materials, which can be used in microbiological, food, chemical and other industries, containing a boot device, a drying chamber, the body of which is made in the form of a rectangular parallelepiped, on the frame of which between the trolleys with trays for wet material installed canopies dividing the chamber space into three zones located one above the other, along which the drying agent moves in succession, and the fresh air heated in the external heater is sucked in by the fan and fed to the bottom of the chamber, where it moves, changing direction twice and heating twice in the intermediate heaters, and part of the exhaust air is directed to mixing with fresh air into the mixing chamber with the help of a gate, and the exhaust air is removed through a dust cleaning system consisting of an acoustic installation and a cyclone (Patent No. 2305236, F26B 9/06).

The disadvantage of this dryer is that it cannot provide the minimum necessary selection of seed moisture per unit time in order to maintain their germination in full, which is necessary for breeding soybean seeds.

A known dryer for heat-sensitive materials - for seed corn on the cob, containing chambers with perforated bottoms, a distribution corridor located between them, divided by a horizontal partition into compartments connected to a fan and atmosphere, and rotary valves that change the direction of movement of the coolant in the chambers to the opposite, when In this case, the compartments are connected to the fan by means of a diffuser with windows on the side surface and with dividing frames inside, adjacent to the partition on one side, and the valves blocking the windows and frame receptions are pivotally mounted on the walls of the diffuser and connected by adjustable length rods (A.S. USSR No. 523257, F26B 9/06).

The disadvantage of this dryer is the complexity of the design and inefficiency for drying breeding soybean seeds.

Known chamber grain dryer containing chambers with perforated bottoms, a distribution corridor between them for the coolant, divided by a horizontal partition into the upper and lower sections. The corridors are connected to the furnace by means of a diffuser, inside which rotary valves are installed - upper and lower, interconnected by rods with couplings for length regulation. Above them, a collection chamber for the spent coolant is formed, on the walls of which there are windows for returning the spent coolant to the furnace through pipelines with autonomous louvre dampers. Above and below the windows there are exhaust windows for ejection of the spent coolant to the outside, which are periodically blocked by gates moving upwards in guides by means of a block-cable system, downwards - under the action of their own weight. The valves move up from the electric winch, and down - under the action of their own weight and the weight of overweight cargoes. Louvre dampers are driven from a common actuator. A fan is installed in the furnace. Outside air enters the furnace through the shutters, and the exhaust heat carrier is supplied to the prechamber zone. There are openings on both sides of the diffuser, covered by segments attached to the valves. On each side of the collection chamber, the gates are interconnected by adjusting rods designed to regulate the degree of opening and closing of the exhaust windows. The dampers are controlled by relative humidity sensors of the exhaust coolant (AS USSR No. 1109565, F26B 9/06, 1984).

The disadvantage of the known grain dryer is the complexity of the design and inefficiency for drying breeding soybean seeds.

As can be seen from the above level of technology, the disadvantages of existing methods and devices for drying seeds are their inefficiency for drying soybean seeds, and especially soybean breeding seeds, which are very easily damaged by mechanical stress and can crack the shell if the rate of evaporation of moisture from the bean shell is exceed the rate of movement of moisture from the center of the grain to the surface.

The task of the claimed group of inventions is to create an effective technology for drying selective soybean seeds.

The goal is to create a simple design of the dryer, which implements a mild drying mode, ensuring uniform drying with smooth removal of moisture, preventing cracking of soybean grains, as well as their mechanical damage.

The technical result of the claimed method of drying breeding soybean seeds is ensured by the fact that the seeds are placed in fabric bags and blown with air at a temperature of 45 ± 2 ° C from two opposite sides of the bags, controlling the relative humidity of the coolant, while when the relative humidity of the coolant reaches 55%, the process is carried out exchange of the coolant with the ambient air for 4 minutes every 30 minutes of drying in cycles until a stable relative humidity of the coolant equal to 27% is reached for 1 ... environment.

Exploring the state of the art in the process of conducting a patent search for all types of information publicly available in the press, we have not identified technical solutions that are close in essence to the claimed method of drying breeding soybean seeds.

As a result of our research on the study of the drying process of breeding soybean seeds on a specially designed prototype dryer, which allows drying operations under various modes, the declared drying operations and their modes were identified, allowing to achieve the goal and solve the problem.

Thus, placing seeds in fabric bags with their subsequent blowing with a coolant excludes direct contact of seeds with loading and unloading chutes, with a slatted bottom, with diaphragms, with walls of drying sections and with other various structural elements of known dryers - depending on the type of their designs. And this saves breeding seeds from mechanical injury, which leads to micro- and macrocracks in the seed coats and the surface tissues of the cotyledons and axial organs of the embryos directly under the shell - the embryonic root, which leads to their death, which is extremely undesirable in breeding work.

Blowing the bags with seeds from two opposite sides provides the possibility of a milder drying mode - at a coolant temperature of 45 ± 2 ° C, a smoother removal of seed moisture, a more productive drying process that ensures the absence of seed cracking, which is very important in breeding.

This is explained by the fact that when blowing bags with seeds from two opposite sides of the bags, the removal of moisture from the entire volume of seeds will be smoother and at the same time more productive than when blowing the same volume of seeds with a coolant.

The exchange of the heat carrier with the ambient air for 4 minutes every 30 minutes of drying in cycles after the heat carrier moisture reaches 55% and until it reaches a stable, within 1–2 hours, heat carrier moisture equal to 27%, ensures a smooth decrease in seed moisture (0.3 ...0.5% per one hour of drying), which eliminates the excess of the rate of evaporation of moisture from the surface of soybean grain over the rate of movement of moisture from the center of the grain to its surface, and therefore does not lead to micro- and macrocracks on the grain shell, which is valuable for breeding soy seeds.

The claimed method of drying breeding soybean seeds is illustrated by drawings: in Fig. 1 shows a graph of changes in the moisture content of the coolant in the process of drying breeding soybean seeds; in fig. 2 - graph of changes in seed moisture depending on the moisture content of the coolant; in fig. 3 shows a graph of changes in the specific moisture removal of seeds per hour.

The technical result of the proposed device for drying breeding soybean seeds is achieved due to the fact that it contains a housing, two identical sections connected by a common partition, each section includes an air chamber in the form of a rectangular parallelepiped, three drying compartments, three doors, a heat generator, a fan, a diffuser coolant supply, coolant cone-distributor, three vertical air corridors, each of which is formed by one of the walls of the air chamber and the door of the drying compartment, an exhaust duct, a heat exchange damper, an air duct for returning the coolant to the heat generator, an angular adapter, an air inflow damper, a coolant return damper, interlocked gate and damper drives using a cable system, heat carrier temperature and humidity sensors, a control panel, a microprocessor, while each drying compartment includes a lattice bin installed in the air corridor at the same distance from the air chamber wall and from the compartment door for placing handbags with seeds, the rear side of which is made in the form of a frame with a system of vertical rods made of profiled rolled products, and the front side is in the form of a frame with horizontally located folding lattice loading and unloading windows mounted on guides fixed on the frame.

The solution is further explained with reference to the drawings. In FIG. 4 schematically shows a two-section chamber dryer with one door removed (front view); in fig. 5 - internal arrangement of dryer sections (front view); in fig. 6 is section A-A in FIG. 5; in fig. 7 - internal arrangement of the drying compartment; figure 8 - bin drying compartment.

The device for drying selective soybean seeds contains a housing 1, two sections 2 connected by a common partition 3, each section includes an air chamber 4, three drying compartments 5, three doors 6 drying compartments, a heat generator 7 with a fan, a diffuser 8 for supplying a coolant, a distribution cone 9 coolant, three vertical air corridors 10, each of which is formed by one of the walls 11 of the air chamber and the door of the drying compartment, an exhaust hood 12, a heat exchange damper 13, an air duct 14 for returning the coolant to the heat generator, an angular adapter 15, an air inlet damper 16, a damper 17 return of the coolant to the heat generator, interlocked drives 18,19, respectively, of the gate and dampers using a cable system 20, sensors 21 for the temperature and humidity of the coolant, a control panel 22, a microprocessor 23, three lattice bins 24 for bags with seeds, a frame 24 bins, folding loading unloading windows 25 bins, guides 26 windows.

A device for drying breeding soybean seeds operates as follows. The operator opens the door 6 of one of the three drying compartments 5, opens the loading and unloading windows 25 in turn, starting from the bottom of the drying compartment, puts soybean seeds through the windows with an initial moisture content, for example 30%, in fabric bags into the bin 24, filling it by 80 ... 90 % of its volume and sequentially closing the windows from the bottom up of this compartment. It closes the compartment door and does the same with the other two compartments of both sections of the dryer, then from the control panel 22 it turns on the heat generator 7.

The drying process begins with heating the air with a heat generator 7 to a temperature of 45±2°C. In this case, the gate 13 and the air intake damper 16 are in the closed position, and the coolant return damper 17 is in the open position. Heated air with a fan (not shown in the drawing) through the diffuser 8 enters the air corridors 10. Rising up, it heats the bags with seeds, which are filled with lattice bins 5, on both sides of the bags. Next, the coolant enters the exhaust duct 12 and through the coolant return air duct 14 through the corner adapters 15 returns to the heat generator 7, making a closed circulation in the internal volume of the sections, taking moisture from the seeds. The microprocessor 23, connected to the temperature and humidity sensors 21 of the heat carrier and to the actuators (not shown in the drawing), analyzes the parameters of the drying process and sets the optimal mode by acting on the actuators of the dryer elements with control signals. So, with an increase in the relative humidity of the coolant above the values \u200b\u200ballowable for soybeans (55%), the drives 18, 19 of the gate 13 and dampers 16, 17, respectively, automatically operate, the gate 13 and the damper 16 of the air intake open and the damper 17 of the air return closes. An air exchange process takes place, in which the moisture content of the coolant decreases within 4 minutes, after which the gate 13 and damper 16 are closed, and the damper 17 opens. The coolant heats up within 30 minutes. The process of air exchange occurs cyclically according to a given program automatically: air exchange lasts for 4 minutes every 30 minutes of heating the coolant, which ensures a smooth removal of seed moisture not higher than 0.5% per hour, preventing their cracking (Fig. 1). The end of the drying process is set by a program that turns off the heat generator and opens the gate 13 and dampers 16.17 upon reaching a stable, within 1 ... more than 0.5% (Fig. 3). At the same time, the fan continues to work, the sections are ventilated with outside air to the ambient temperature with a decrease in the temperature and humidity of the seeds in the bags.

Example.

In a particular case of the implementation of the invention, a chamber dryer was made for drying breeding soybean seeds with the following technical characteristics: the number of sections - 2 pcs, the number of drying compartments with bins in the chamber - 6 pcs, the capacity of the chamber for soybean seeds - 200 kg, the weight of the seeds in one bag - from 1.5 kg to 4 kg, thickness of the lattice bin - 60 mm, air temperature in the chamber - 45±2°C, air circulation in the chamber - 390 m ³ /h, dimensions of the dryer: length - 1600 mm, width -860 mm, height - 1950 mm, weight - 270 kg, maximum power consumption - 6.5 kW, partial power consumption - 3.5 kW.

Drying of soybean seeds was carried out according to the claimed method (Fig. 1) to a final seed moisture content of 14% (Fig. 2 and Fig. 3) at which the quality of breeding soybean seeds is maintained, due to the smooth removal of seed moisture, not more than 0.5% per hour.

Thus, the claimed group of inventions offers an effective technology for drying breeding soybean seeds, including a simple dryer design that performs a mild drying mode with a smooth removal of seed moisture, preventing cracking and mechanical damage.

The features of the claimed inventions are necessary and sufficient to carry out the drying of breeding soybean seeds while maintaining their breeding quality in a soft mode while ensuring a specific moisture removal of not more than 0.5% per hour, i.e. to achieve the goal and solve the problem.

Claims (2)

1. A method for drying soybean breeding seeds, characterized in that the seeds are placed in fabric bags and blown with air at a temperature of 45 ± 2 ° C from two opposite sides of the bags, controlling the relative humidity of the heat carrier, while when the heat carrier humidity reaches 55%, the exchange process is carried out coolant with ambient air for 4 minutes every 30 minutes of drying the seeds in cycles until a stable relative humidity of the coolant equal to 27% is reached for 1-2 hours, after which the seeds are cooled by blowing with ambient air to the ambient temperature. 2. Chamber dryer of breeding soybean seeds placed in fabric bags, characterized in that it contains a body, two identical sections connected by a common partition, each section includes an air chamber in the form of a rectangular parallelepiped, three drying compartments, three doors, a heat generator, a fan, coolant supply diffuser, coolant cone-distributor, three vertical air corridors, each of which is formed by one of the walls of the air chamber and the door of the drying compartment, exhaust hood, heat exchange damper, coolant return air duct to the heat generator, angular adapter, air inlet damper, coolant return damper , interlocked gate and damper drives using a cable system, heat carrier temperature and humidity sensors, a control panel, a microprocessor, while each drying compartment includes a lattice bin installed in the air corridor at the same distance from the air chamber wall and from the door for placing handbags with seeds, the rear side of which is made in the form of a frame with a system of vertical rods made of profiled rolled products, and the front side is in the form of a frame with horizontally located folding lattice loading and unloading windows mounted on guides fixed on the frame.

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