JP3213240U - Continuous grain dryer - Google Patents

Abstract

The present invention provides a continuous grain drying apparatus that improves drying capacity and quickly discharges dried grains to improve drying efficiency. A drying machine main body including a storage unit, a drying unit, a tempering unit, and a cooling unit, a grain discharging mechanism installed at the bottom of the cooling unit, and a grain discharging mechanism. A hot air oven 10 connected to the dryer main body through a hot air duct 8 and a grain elevator 18 installed on one side of the dryer main body. And a grain supply hopper 13 installed at the bottom of the grain elevator, and a grain supply pipe 22 installed between the grain elevator and the storage unit, and the grain to be dried is put into the grain supply hopper, and the grain elevator After transporting to the top of the device through the grain supply pipe, put it into the dryer body, pass through the drying part, tempering part and cooling part in order from the storage part, and finally pass through the grain discharge mechanism Let dry It is formed. [Selection] Figure 4

Description

The present invention relates to the field of grain drying, and more particularly to a continuous grain drying apparatus.

Grain drying is very important because the main purpose is to keep the drying process stable and to remove moisture in the grain with the lowest drying cost and energy consumption. .

In the conventional grain drying process, it is common to detect moisture by online methods such as capacitance method or resistance method, but recently, in China, online detection of moisture based on weight. And new research and trends on control have emerged.

The principle of on-line moisture detection by the resistance method is to indirectly measure grain moisture based on the relationship between grain moisture and its resistance value. The higher the moisture, the lower the resistance, and the lower the moisture, the lower the resistance. It is expensive. Circulating grain dryers usually perform on-line detection using a resistance moisture sensor mounted on the side wall of the elevator elevator, and the grains dropped from the elevator buckets are Falling continuously on a pair of relatively rotating rollers, the grain is crushed as it passes through the roller, and at the same time, the resistance change curve of the material between the roller electrodes is measured, and the resistance change of a given number of grains The curve eigenvalues are extracted and dynamically statistically calculated to obtain the average value. Based on the relationship between the average value and the moisture (corrected), the moisture value of the grain is obtained, and finally, based on the moisture value. Target control or process control during grain drying process. Famous dryer production companies such as Kaneko Agricultural Machinery Co., Ltd. in Japan, Sankusha in Taiwan, and Satake Nihonsha all use online moisture detectors based on these principles. Nagatomo has developed an on-line moisture detector based on the principle of resistance method in a Chinese application with disclosure number CN1963478 A. The disadvantages of online moisture detection by the resistance method are as follows. 1. If the moisture of the grain is uneven and a large number of blue immature grains and immature grains are contained, the error of the detection value becomes large. 2. The structure is complicated and failures often occur. 3. If there are foreign objects such as stones in the material, the roller is likely to be clogged or damaged. 4. Applicable only to grains with similar traits and grain sizes, such as rice and wheat, etc. When the grain type changes, the sensor needs to be changed greatly. 5. It is damage detection. 6. Low moisture detection accuracy for high moisture grains.

The principle of on-line moisture detection by capacitance method is to indirectly measure grain moisture based on the relationship between grain moisture and capacitance method, the higher the moisture, the greater the capacitance. The lower the moisture, the smaller the capacitance. Conventionally, when using an electrostatic grain moisture sensor, an automatic grain dryer generally attaches a cylinder having a certain capacity to the grain flow inside or at the outlet of the tempering part of the circulating grain dryer, The change in moisture content is measured based on the fact that the dielectric properties differ for different grain moisture due to the grain flowing through the capacitance plate. Moisture is detected and then a secondary instrument or master computer is used to adjust the control for grain drying based on the grain moisture value. Domestic companies such as Changchun Yoshida Science Equipment Co., Ltd. and Shanghai Lingzhou Co., Ltd. produce such online moisture detectors. The disadvantages are as follows. 1. Installation and maintenance are inconvenient. 2. Detection accuracy depends on environment, grain temperature and humidity, grain density, grain flow rate. 3. When the content of foreign matter in grain is high, the error of monitoring detection is large.

The principle of online moisture detection by the gravimetric method is based on the method of performing moisture detection based on the fact that the weight of materials with different moisture contents per unit volume is different, or based on weight loss under conditions where the initial moisture is known. This is a method for calculating the moisture of grains online in real time. While the weight detection method has the advantage of high accuracy and excellent stability, it has the disadvantage of being inconvenient and difficult to eliminate dynamic errors. In Chinese application No. 2013106682977.8, named online moisture monitoring method for grain circulation drying based on total weight detection and its system, a real-time online detection method by weight detection is disclosed.

The present invention improves the drying capacity of the dryer by providing a plurality of drying units and tempering units inside the dryer, and a grain discharge mechanism is installed at the bottom of the cooling unit, so that the dried grains Develop a continuous grain drying device that quickly discharges and improves drying efficiency.

The technical proposal provided by the present invention is as follows.

Continuous grain drying equipment
A dryer body including a storage unit, a drying unit, a tempering unit, and a cooling unit communicating in order from top to bottom;
A grain discharge mechanism installed at the bottom of the cooling unit;
A dryer base installed at the bottom of the grain discharge mechanism;
A hot air oven connected to the dryer body by a flexible connection method,
A grain elevator installed on one side of the dryer body;
A grain transport pipe installed between the grain elevator and the storage unit;
A dryer total weight sensor disposed on the bottom end of the column of the dryer body base or on the column.

Preferably, the grain discharge mechanism comprises:
An upper support frame that is a rectangular frame;
A lower support frame installed below the upper support frame and having a side length smaller than the side length of the upper support frame;
A grain conveying plate connecting the upper support frame and the lower support frame;
A grain discharging wheel, which is installed between the grain conveying plates and is a rotary wheel with blades.

Preferably, the rotating wheel has six blades.

Preferably, the top of the grain elevator is higher than the top of the reservoir.

Preferably, the dryer base is
A base column that supports the dryer body;
A conical hopper for collecting grains, which is installed inside the base column, connected to a conveyor, and transports dried grains to the outside of the machine;

Preferably, the hot air furnace is a coal fired hot air furnace, an oil fired hot air furnace, or a gas fired hot air furnace.

Preferably, further, a level sensor attached to the top of the dryer body,
A temperature / humidity probe unit is provided at the top of the dryer main body and located below the level sensor.

Preferably, the temperature / humidity probe unit includes a plurality of temperature sensor probes and a plurality of humidity sensor probes.

The present invention improves the drying capacity of the dryer by providing a plurality of drying units and a tempering unit inside the dryer, and provides a grain discharge mechanism at the bottom of the cooling unit, so that the dried grains can be removed. Develop a continuous grain drying device that discharges quickly and improves drying efficiency.

The online moisture detection system for continuous grain drying provided by the present invention has advantages such as simple configuration, easy installation, easy operation, high anti-interference ability, and excellent environmental compatibility. Suitable for continuous drying of crops such as wheat, avoiding the main deficiencies of moisture detection by the prior art.

It is a schematic diagram of the online moisture monitoring method of a continuous grain dryer. It is an equivalent graph of the operation | work of a continuous grain dryer. It is a block diagram of the system of a continuous grain dryer. It is a structure schematic diagram of a continuous grain dryer. It is a circuit schematic diagram of a continuous grain dryer.

Hereinafter, the present invention will be described in more detail with reference to the drawings so that those skilled in the art can implement it with reference to the specification.

As shown in FIG. 3-4, the continuous grain drying apparatus of the present invention includes a dryer body 1, a hot air duct 8, a hot air machine 9, a cold air machine 6, a hot air furnace 10, a grain elevator 18, and a dryer total weight sensor. A unit 7, a signal detection conversion unit 12, a control / display unit 11, a temperature / humidity probe unit 20, a level sensor 21, and a grain supply pipe 22 are provided.

When performing the drying operation, the grain to be dried is transported into the drying body 1 and the dryer total weight sensor unit 7 is installed on the bottom end of the base column of the dryer body 1 or on the column. 7 and the signal detection conversion unit 12 are connected, and the signal detection conversion unit 12 and the control / display unit 11 are connected. The dryer total weight sensor unit 7 detects the total weight of the dryer main body 1 and the grain, transmits a detection signal to the signal detection conversion unit 12, and displays it on the screen by the control / display unit 11.

The hot air fan 9 is connected to the hot air furnace 10, the hot air furnace 10 is connected to the dryer main body 1 via the hot air duct 8, and the grain elevator 18 is connected to the top of the dryer main body 1 via the grain supply pipe 22. Yes. The level sensor 21 includes an upper level sensor and a lower level sensor, and is attached to the upper part of the dryer main body 1. The temperature / humidity probe unit 20 is attached to the upper part of the dryer main body 1, and Located on the bottom side.

As shown in FIG. 3, the dryer main body 1 includes a storage unit 2, a drying unit 3, a tempering unit 4, and a cooling unit 5 in order from top to bottom. A grain discharge mechanism 6 and a dryer base 16 are installed below the cooling unit 5. Preferably, the level sensor 21 and the temperature / humidity probe unit 20 are attached to the reservoir 2. Preferably, the temperature / humidity probe unit 20 includes a plurality of humidity probes and a plurality of temperature probes. The storage unit 2 plays a role of temporarily storing the grains in the dryer before putting them in the drying unit 3 and drying them. Below the storage unit 2 is a tempering unit 4. Preferably, in order to improve the drying capacity and drying speed of the dryer, a plurality of drying units 3 and tempering units 4 are provided inside the dryer, and the grains are subjected to multi-stage drying and tempering, When entering the cooling section 5 and satisfying moisture requirements for the grain, it is cooled and enters the grain discharge mechanism 15 and is discharged from the cone hopper for collecting grains in the dryer base 16 to the discharge grain conveyor 14 and transported to the grain storage location. Thus, the grain drying process is completed, and when the grain position is lower than the position of the lower level sensor, a new grain to be dried is supplied.

By detecting the moisture or moisture change rate of the grain, the grain discharge rate and / or drying temperature is manually adjusted or automatically adjusted to match the grain moisture change and the grain discharge rate and / or drying temperature, After passing through the drying section, tempering section, and cooling section of the dryer, it falls within the moisture threshold range. As a non-limiting illustrative example, a low grain moisture drying rate reduces the grain discharge rate and / or increases the drying temperature, and a too high grain moisture drying rate increases the grain discharge rate. And / or reduce the drying temperature. Preferably, a conventional PID control method can be used as a measure for automatically controlling the grain discharge rate and / or drying temperature.

As shown in FIG. 3, the hot air fan 9 and the hot air duct 8 are connected in a flexible connection form, and the hot air duct 8 and the dryer main body 1 are connected in a flexible connection form. Preferably, the hot air duct 8 and the flange of the dryer main body 1 are integrally connected by a heat insulating flexible connector. Thus, the influence on the detection accuracy of the weighing sensor unit 7 due to the vibration of the hot air fan 9 is avoided. Preferably, here, a coal-fired hot stove may be used as a heat source, and the drying medium may be provided by an oil or gas-fired hot stove.

As shown in FIG. 4, when the dryer is activated, the grains enter the grain supply hopper 13 and are transported from the bottom to the top by the grain elevator 18 to the top of the dryer body 1, and the elevator 18 and the dryer body. 1 is uniformly sprinkled in the dryer main body 1 through the grain supply pipe 22 between 1 and moved downward by using gravity, respectively, through the storage unit 2, the drying unit 3, and the tempering unit 4, After performing multi-stage drying and tempering, the cooling unit 5 is entered, then the six-sheet impeller grain discharging mechanism 15 is discharged, and the grain discharging mechanism 15 discharges while controlling the grain discharging speed, and then the discharged grain conveyor. 14 through a grain storage silo or grain transport vehicle. On one side where the duct of the dryer main body 1 is attached, the heat medium is blown into the dryer by a wind blow method to dry the grains. Wet exhaust obtained by heat and mass transfer of the heat medium and the grain to be dried is discharged from the moisture outlet 17. The drying process is completed by performing multi-stage drying of the grain in the dryer and discharging the grain through the grain discharging mechanism 15 and the discharging grain conveyor 14.

Preferably, the grain discharging mechanism includes an upper support frame that is a rectangular frame, a lower support frame that is installed below the upper support frame and has a side length smaller than a side length of the upper support frame, and the upper support frame. A grain conveying plate for connecting the lower support frame; and a grain discharging wheel which is installed between the grain conveying plates and is a blade, preferably a rotating wheel with six blades.

Preferably, when performing the drying operation, the grain elevator 18 and the discharge grain conveyor 14 operate simultaneously in a balanced manner to cooperate with the level sensor 21 to keep the grain weight in the dryer constant or within a small range. .

As shown in FIGS. 3 and 4, the dryer weighing sensor unit 7 includes a plurality of weighing sensors attached to the bottom end of the column of the dryer base 16 or on the column. The mounting method of the weighing sensor can be determined according to the sensor type. When the grain weight in the dryer main body 1 changes, the change in weight applied to the column of the dryer base is converted into a voltage signal by the weight sensor unit, and the voltage signal is transmitted to the signal detection conversion unit 12.

As shown in FIG. 5, the signal detection conversion unit 12 collects voltage signals and performs analog / digital conversion. The unit includes a filtering amplification circuit, an analog / digital conversion circuit, a watchdog circuit, an MCU signal processing device, and an RS485 serial communication circuit.

In order to eliminate noise and amplify the signal, a filtering amplifier circuit is installed in the front part. Next, the analog signal is connected to an analog / digital conversion circuit to convert the analog signal into a digital signal receivable by the master computer. Further, the MCU signal processing circuit and the analog / digital conversion circuit are connected to process the received digital signal. Connect the watchdog circuit and MCU circuit to prevent program lock and loss. Finally, the processed signal is transmitted to the control / display unit 11 via the RS485 serial communication circuit.

Here, the noise of the voltage signal is filtered by the filtering amplifier circuit, so that the interference signal is removed and the effective signal value is amplified. Since the voltage signal subjected to the filtering amplification process is still an analog quantity and cannot be received by the master computer, the signal is converted into a digital signal that can be received by the master computer by the analog / digital conversion circuit. The digital signal is calculated via an MCU signal processing circuit. The MCU signal processing circuit is a single chip microcomputer signal processing circuit.

The temperature / humidity probe unit 20 transmits the temperature / humidity of the environment and the temperature / humidity signal in the dryer main body 1 to the MCU signal processing circuit. Preferably, a system ST800 temperature / humidity probe unit can be used as the temperature / humidity probe unit 20. By connecting the signal of the level indicator 21 and the signal detection conversion unit 12, the height of the grain in the dryer main body 1 is determined, and the operation of the grain elevator 18 is controlled based on this height. Preferably, an infrared laser type level sensor or a rotational resistance type level switch can be used as the level indicator 21.

When the MCU is running, software execution failure or program to prevent the infinite loop of the system from occurring due to problems such as program loss, memory failure, external interference or misoperation. A watchdog circuit whose basic function is to initialize a program when a failure occurs has been added. Thus, when such interference occurs in the system, the operational stability of the device itself can be greatly improved by resetting immediately. In that case, a digitized and stable calculated signal is transmitted to the control and display unit 11.

The online moisture detection method in the continuous grain drying process includes the following steps.

Initialization: The initial moisture value M ₀ , the heat medium temperature T, and the initial grain discharge rate G _g of the grain to be dried are input and stored in the control / display unit of the dryer.

Tare Detection: with no grain in the interior of the dryer and weighing sensor unit attached to a lower portion of the dryer, by detecting the tare W _b, are read and stored.

Activation of grain supply operation with level double control: The grain supply to the dryer is activated manually or automatically, the grain to be dried is transported into the dryer, and the grain in the dryer is at the position of the upper level sensor. When it reaches, the grain supply is automatically stopped, and when the grain in the dryer is lower than the position of the lower level sensor, the grain feeder is activated.

Heat source supply and grain discharge device activation: Heat medium supply blower and grain discharge device are activated according to a certain time interval and order.

Real-time detection of total weight and level: At regular intervals, the total weight W _j and level height H _j are detected in real time, read and stored, and the volume V _j and volume weight ρ _j are calculated. Or when the grain fed to the dryer with two levels controlled reaches an upper level, the initial total weight W ₀ (weight at the upper level) and the initial level height H ₀ are determined. Next, during the period when the feeding process is not activated, the real-time total weight W _j is continuously detected, read and stored, and the level height H is set using the set dry grain discharge rate G _{g. j} , volume V _j and volume weight ρ _j are calculated.

Using the conversion relationship between the moisture and the volume weight, the real-time average moisture value M _j of the grain inside the dryer is calculated and displayed.

Hereinafter, the average moisture detection will be described with reference to FIG. 2, and a dryer having various forms regardless of the number of the forward flow, the reverse flow, the cross flow, or the mixed flow, and the number of drying sections and tempering sections is illustrated in FIG. 1. The model corresponding to the structure shown can be simplified, and the drying body can be divided into n thin layers from top to bottom. The more thin layers, the larger the n value and the higher the accuracy of calculation. .

By installing a total weight detection sensor unit on the bottom base of the dryer and a switch type or continuous level sensor on the top of the dryer, the grain weight and level height inside the dryer can be detected in real time, and further the dryer The volume weight of the internal grain is calculated, and then the average moisture is calculated based on the relationship between the prepared grain moisture and the grain volume weight. Alternatively, the average grain moisture may be calculated based on the moisture conversion relationship using the known grain initial moisture and the detected total grain weight.

Real-time total weight W _j and level of internal grain dryer height H _j and detected continuously, read recorded and, calculated or detected and real-time volume V _i and the volumetric weight [rho _j Grain Further, the real-time average moisture value M _j of the internal grain of the dryer is calculated and displayed based on the following formula. Preferably, in order to achieve more accurate detection accuracy, the batch feed is automatically controlled using two level meters in the course of wet grain entering the dryer, while the grain is not being fed ( Measure grain total weight and height).

In the table, “B ₁ C ₁ ; B ₂ C ₂ ;... B _L C _L ” is obtained by testing under the conditions of a specific variety of grain, a specific dryer model number, and a specific drying process. It is a set of data on the relationship between moisture and volume weight of cereals.

Application example of cross-flow multi-layer continuous drying process for corn, wheat and rice in Tohoku area.

In Table 2, the coefficients of the formula in the first column are applicable when the average moisture of the corn inside the dryer is lower than 23% and include the general work situation for the corn (moisture when entering the dryer) If the condition is not satisfied, the temperature or grain discharge rate is to be adjusted manually.

Preferably, when using the data in Table 3, the fitting may be performed by linear or nonlinear interpolation. Columns 1 and 2 are applicable when the average moisture content of the internal corn of the dryer is lower than 23%, and includes general work conditions for corn (when the moisture content in the dryer is about 30%) Is the normal working situation), if the conditions are not met, it is to manually adjust the temperature or grain discharge rate.

The online moisture detection system for continuous grain drying provided by the present invention has advantages such as simple configuration, easy installation, easy operation, high anti-interference ability, and excellent environmental compatibility. Suitable for continuous drying of crops such as wheat, avoiding the main deficiencies in prior art moisture detection.

Although the embodiments of the present invention have been disclosed above, the present invention is not limited to the uses shown in the specification and the embodiments, and can be used in various fields suitable for the present invention. Thus, the present invention is not limited to the specific details and examples of figures described herein, unless it departs from the general concept limited by the claims and the equivalents.

Claims (8)

A continuous grain dryer,
A dryer body including a storage unit, a drying unit, a tempering unit, and a cooling unit communicating in order from top to bottom;
A grain discharge mechanism installed at the bottom of the cooling unit;
A dryer base installed at the bottom of the grain discharge mechanism;
A hot air oven connected to the dryer body by a flexible connection method,
A grain elevator installed on one side of the dryer body;
A grain transport pipe installed between the grain elevator and the storage unit;
A continuous grain drying apparatus comprising a dryer total weight sensor disposed on a bottom end of the column of the dryer main body base or on the column. The grain discharge mechanism is:
An upper support frame that is a rectangular frame;
A lower support frame installed below the upper support frame and having a side length smaller than the side length of the upper support frame;
A grain conveying plate connecting the upper support frame and the lower support frame;
The continuous grain drying apparatus according to claim 1, further comprising a grain discharge wheel that is installed between the grain conveying plates and is a rotary wheel with blades. The continuous grain drying apparatus according to claim 2, wherein the rotating wheel has six blades. The continuous grain drying apparatus according to claim 1, wherein a top of the grain elevator is higher than a top of the storage unit. The dryer base is
A base column that supports the dryer body;
The continuous grain drying apparatus according to claim 1, further comprising a conical hopper for collecting grains, which is installed inside the base column and is connected to a conveyor and transports dried grains to the outside of the machine. The continuous grain drying apparatus according to any one of claims 1 to 5, wherein the hot air furnace is a coal fired hot air furnace, an oil fired hot air furnace, or a gas fired hot air furnace. A level sensor attached to the top of the dryer body,
The continuous grain drying apparatus according to claim 6, further comprising a temperature and humidity probe unit attached to an upper portion of the dryer main body and positioned below the level sensor. The continuous grain drying apparatus according to claim 7, wherein the temperature and humidity probe unit includes a plurality of temperature sensor probes and a plurality of humidity sensor probes.