Shutdown control method for granulating device

Abstract

The invention belongs to the technical field of grain feed processing equipment. The shutdown control method of the granulating device is characterized in that a temperature sensor is arranged at a discharge port of a feeder, and the control method is as follows: during normal production, the temperature of an outlet of the feeder is T1-T2; the current of the granulator main machine is I1-I2; when the temperature sensor monitors that the temperature of the outlet of the feeder is abnormally and rapidly increased, it is judged that no material exists in the to-be-granulated bin and the feeder, the feeder is closed, and a steam control valve on a steam assembly of the conditioner is closed; monitoring current data of the granulator host in real time; when it is monitored that the current of the main machine of the granulator is reduced to no-load current and is kept for 5-10 s, it is judged that the main machine of the granulator is in the no-load state, and the materials in the conditioner are completely discharged; and closing the conditioner layer by layer from top to bottom, and then closing the main machine of the granulator to finish shutdown. The automatic shutdown system is used for solving the technical problem that an existing automatic shutdown system for the granulation section cannot achieve accurate shutdown.

Description

Technical Field

[0001] The invention belongs to the technical field of grain and feed processing equipment, and in particular relates to a shutdown control method for a granulating device. Background Art

[0002] The feed pelletizing section is generally composed of a pelletizing bin, a feeder, a conditioner, a quality controller, a pelletizing machine, a steam adding system, a gear lubrication system, etc. The powdered material after crushing is temporarily stored in the pelletizing bin, and then enters the feeder, which provides the power for forward flow, and enters the conditioner. The material is mixed with steam inside the conditioner, heated and matured, and then enters the pelletizer for extrusion pelletizing.

[0003] At present, the automatic shutdown of the pelleting section in the feed industry is based on the material level signal at the bottom of the pelleting bin to be fed back that the material is exhausted, and then by setting a delay time, it is considered that after a certain delay, there is no material inside the feeder, and the feeder and steam are turned off, and then the conditioner is turned off after a delay, etc., that is, the material level at the bottom of the pelleting bin is used to trigger the material shortage signal, and the system sets a delay time to delay the stop of the feeder, conditioner and other equipment. There are two problems with this system: on the one hand, the material level signal is prone to failure and cannot provide accurate material level signals, causing steam to enter the pelleting bin and cause material supply to be blocked; on the other hand, the delayed shutdown is related to the current pellet mill capacity, and the delay time makes it difficult to accurately judge whether the material inside the feeder or conditioner has been completely discharged, resulting in material waste.

[0004] As the market competition in the feed processing industry becomes increasingly fierce, the requirements for feed processing costs are getting higher and higher. On the one hand, it is necessary to reduce the demand for personnel and achieve full automation, but the existing technology cannot provide a reliable automatic shutdown control system. Since the material level sensor under the pelletizing bin often gives false alarms, resulting in abnormal shutdowns, the market application effect is not good, and most of them still use manual shutdowns, which require operators to check in real time and cannot reduce labor costs.

[0005] In addition, the prior art is to set a shutdown delay, that is, after the material level alarm, delay for a period of time, turn off the feeder and steam, and then delay for a period of time to turn off the conditioner, main machine, etc. The delay time parameter is related to the production capacity of the pelletizer. If the production capacity is large, the delay time should be set shorter, and if the production capacity is small, the delay time should be set longer. Therefore, it is difficult to set this parameter accurately. If the delay time is set shorter than the actual required time, the material inside the feeder or conditioner will not be completely discharged, resulting in a waste of raw materials. If the delay time is set to a value longer than the actual required time, steam will enter the granulation bin to form condensed water, which will affect the material level sensor signal in the granulation bin, forming a vicious circle. Summary of the invention

[0006] The purpose of the present invention is to provide a granulation device shutdown control method to solve the technical problem that the existing granulation section automatic shutdown system cannot achieve accurate shutdown.

[0007] In order to solve the above technical problems, the present invention adopts the following technical scheme, a granulating device shutdown control method, characterized in that the granulating device comprises a granulating bin, a feeder, a conditioner, a quality preserver, and a granulator main machine, a temperature sensor is provided at the discharge port of the feeder to obtain temperature data of the discharge port of the feeder; a steam component is provided on the conditioner, and a steam control valve is provided on the steam component; The control method is: During normal production, the temperature of the feeder outlet is T1-T2; the current of the granulator main machine is I1- I2; When the temperature sensor detects that the outlet temperature of the feeder rises abnormally and rapidly, it is determined that there is no material in the granulation bin and the feeder, the feeder is closed, and the steam control valve of the conditioner is closed; Real-time monitoring of the current data of the granulator host; When it is monitored that the current of the granulator main engine drops to the no-load current and remains for 5-10s, it is determined that the granulator main engine is in a no-load state, and the material in the conditioner is drained; the conditioner is closed layer by layer from top to bottom, and then the granulator main engine is closed to complete the shutdown.

[0008] The present invention utilizes the temperature variation characteristics of the feeder outlet to judge whether there is no material in the granulation bin. If the temperature rises abnormally quickly, it is judged that there is no material in the granulation bin and the feeder, and the feeder and the steam valve are quickly closed.

[0009] The invention captures the current of the granulator host to judge whether the granulator is in a no-load state. If the granulator is in the no-load state, it means that the material in the conditioner has been completely discharged, and then the conditioner, the granulator host and other equipment are stopped.

[0010] The present invention can completely realize the automatic shutdown of the granulation section, and can ensure the stability of the shutdown signal, solve the problem of residual inside the feeder and the conditioner. At the same time, it effectively avoids the risk of steam entering the granulation bin, is more reliable, and can realize the full automation control of the granulation section.

[0011] In order to solve the technical problem of how to use a temperature sensor to monitor the abnormally rapid rise in the outlet temperature of the feeder, the present invention adopts the following technical solution: when the temperature sensor monitors that the outlet temperature of the feeder rises to T3-T4, T3=1.2 T1, T4=1.2 T2, it is determined that there is no material in the granulation bin and the feeder, the feeder is closed, and the steam control valve of the conditioner is closed.

[0012] In order to solve the technical problem of how to use the temperature sensor to monitor the abnormal rapid rise of the feeder outlet temperature, the temperature sensor detects the temperature at a time interval t, and continuously records the adjacent time intervals t1-t n The temperature difference is calculated by the average value of the temperature difference; At a certain time point t i When the temperature difference exceeds twice the average value, it is determined that there is no material in the granulation bin and the feeder, and the feeder is closed, and the steam control valve of the conditioner is closed.

[0013] At the same time, close all steam valves in the conditioner. In fact, the steam is turned off as soon as the material in the feeder is emptied. At this time, there is still a part of the tailings running in the conditioner. If the steam is completely turned off at this time, the last tailings may not be fully conditioned.

[0014] In order to solve the above technical problems, the present invention adopts the following technical solution: a plurality of steam components are sequentially arranged on the conditioner along its length direction, and each steam component is respectively provided with the steam control valve; When the temperature sensor detects that the outlet temperature of the feeder rises abnormally and rapidly, it is determined that there is no material in the pelletizing bin and the feeder, the feeder is closed, and the steam valve of the steam component closest to the feeder outlet is immediately closed, and then the delay time t is set. 延时 , from the inlet to the outlet of the conditioner, close the steam control valves of the corresponding steam components in sequence, the steam will not enter the feeder, and the tailings can continue to be heated.

[0015] In order to further solve the technical problem of how to improve the control accuracy, the present invention adopts the following technical solution: a material level sensor is arranged on the granulation bin; When the material has not reached the material level sensor, the temperature sensor performs detection at a first time interval t; When the material reaches the material level sensor, it means that the silo is about to be emptied and there is a little material being delivered in the feeder. The temperature sensor increases the detection frequency and performs detection at a second time interval t', which is smaller than the first time interval t; If the material level sensor does not detect the signal that the material level has reached the bottom, and the temperature sensor still shows an abnormal temperature rise, then the material level sensor is faulty, or an arch has formed in the silo, and the machine is shut down to achieve more precise control.

[0016] In order to solve the technical problem of how to realize the granulation device, the present invention adopts the following technical scheme: the granulation bin, the feeder, the conditioner, the quality preserver and the granulator are arranged in sequence from top to bottom.

[0017] In order to solve the technical problem of how to realize the granulating device, the present invention adopts the following technical solution: the conditioner includes at least two conditioners, the conditioner is arranged between the feeder and the quality preservation device, and the conditioner is arranged between the feeder and the granulator.

[0018] In order to solve the technical problem of the feeder outlet temperature in normal production, the present invention adopts the following technical solution. In normal production, the feeder outlet temperature T1-T2 is slightly higher than the room temperature.

[0019] In order to solve the technical problem of the outlet temperature of the feeder in normal production, the present invention adopts the following technical solution. In normal production, the outlet temperature of the feeder is 35-45°C. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic structural diagram of the granulation device of the present invention; Figure 2 It is a flow chart of the shutdown control method of the granulating device of the present invention; In the figure: 10. Granulation device; 100 silo for pelletizing; 110 material level meter; 200 feeder; 300 conditioner; 400 quality preserver; 500 pelletizing machine; 600 temperature sensor. DETAILED DESCRIPTION

[0021] The present invention will be further described below in conjunction with the accompanying drawings.

[0022] Example 1 like Figure 1 As shown, the granulation device 10 comprises a granulation bin 100, a feeder 200, a conditioner 300, a quality preserver 400, and a granulator main unit 500. A lower material level meter 110 is installed on the granulation bin 100.

[0023] In one embodiment, the granulation bin 100, the feeder 200, the conditioner 300, the quality preservation device 400, and the granulator main machine 500 are arranged in sequence from top to bottom.

[0024] In one embodiment, the number of the conditioner 300 includes at least two. The outlet of the pelletizing bin 100 is connected to the inlet of the feeder 200. The conditioner 300 is arranged between the feeder 200 and the quality preservation device 400, and the conditioner 300 is installed between the quality preservation device 400 and the pelletizing machine mainframe 500.

[0025] The conditioner 300 is provided with a steam component, and the steam component is provided with a steam control valve.

[0026] A temperature sensor 600 is installed at the discharge port of the feeder 200 to obtain temperature data of the discharge port of the feeder.

[0027] The principle of judging the material in the granulation bin by using the temperature variation characteristics of the feeder outlet: The movement process of materials in the granulating device is: granulating bin - feeder - conditioner (multi-layer) - granulator, steam is added in the conditioner on the top layer. The temperature sensor is installed at the outlet of the feeder, that is, the inlet of the conditioner on the top layer.

[0028] During normal production, the material enters the uppermost conditioner from the feeder outlet. Because the material passes through this channel, the steam added in the uppermost conditioner will not enter the feeder. The temperature there is slightly higher than the room temperature and remains stable or fluctuates slowly.

[0029] When all the materials in the pelletizing bin are finished and the materials in the feeder are finished, no more materials will enter the uppermost conditioner through this channel. The steam in the conditioner will quickly enter this channel, causing the temperature to rise abnormally quickly. By judging this phenomenon of the temperature sensor, it can be determined that there is no material in the pelletizing bin and the feeder, and the feeder and steam valve can be quickly closed.

[0030] When there is no material inside the pelletizing bin and feeder, the temperature change phenomenon needs to be compared and identified according to the actual application situation and the temperature phenomenon during normal production.

[0031] Automatic shutdown control principle of granulation section: When the temperature at the feeder outlet rises abnormally, there is no material in the feeder and the granulation bin. At this time, quickly close the steam valve and feeder.

[0032] When the pellet mill is in normal production, the current will be related to the amount of material entering the pellet mill. The more material enters the pellet mill, the higher the current will be, and vice versa. When the material in the conditioner is completely drained, that is, no material enters the pellet mill, the current of the pellet mill will drop to and stabilize at a lower current. At this time, the conditioners can be stopped layer by layer. After all the conditioners are stopped, the pellet mill will be stopped to complete the entire shutdown process.

[0033] like Figure 2 As shown, the granulation device shutdown control method, During normal production, the temperature of the feeder outlet is T1-T2; the current of the granulator main machine is I1- I2; When the temperature sensor detects that the outlet temperature of the feeder rises abnormally and rapidly, it is determined that there is no material in the granulation bin and the feeder, the feeder is closed, and the steam control valve of the conditioner is closed; Real-time monitoring of the current data of the granulator host; When it is monitored that the current of the granulator main engine drops to the no-load current and remains for 5-10s, it is determined that the granulator main engine is in a no-load state, and the material in the conditioner is drained; the conditioner is closed layer by layer from top to bottom, and then the granulator main engine is closed to complete the shutdown.

[0034] During normal production, the feeder outlet temperature T1-T2 is slightly higher than room temperature, preferably 35-45°C.

[0035] The invention captures the current of the granulator host to judge whether the granulator is in a no-load state. If the granulator is in the no-load state, it means that the material in the conditioner has been completely discharged, and then the conditioner, the granulator host and other equipment are stopped.

[0036] The present invention can completely realize the automatic shutdown of the granulation section, and can ensure the stability of the shutdown signal, solve the problem of residual inside the feeder and the conditioner. At the same time, it effectively avoids the risk of steam entering the granulation bin, is more reliable, and can realize the full automation control of the granulation section.

[0037] Example 2 When the temperature sensor detects that the outlet temperature of the feeder rises to T3-T4, T3=1.2 T1, T4=1.2T2, it is determined that there is no material in the granulation bin and the feeder, and the feeder is closed, and the steam control valve of the conditioner is closed.

[0038] Specifically: In the granulation conditioning section, the conditioning chamber temperature is generally required to be 65-80℃ according to different materials and process requirements, and the temperature at the feeder outlet will be heated to a certain extent due to the connection with the conditioner, but it will not reach the temperature in the conditioner due to the isolation of the continuously flowing material. For example, under certain processing conditions, the temperature at the feeder outlet fluctuates slowly around 40℃, may rise slowly from 35 to 45℃ for a period of time, may slowly drop from 45 to 38℃, or may fluctuate slowly around 42℃. However, as long as there is material flowing, the material will not rise rapidly in a short period of time.

[0039] In one embodiment, the temperature measured by the temperature sensor is recorded at a certain time interval, and the temperature average value is calculated. When the temperature change reaches 20%, it is determined that the temperature change is abnormal, and the steam is turned off. For example, if the average temperature of a batch of materials measured during normal production is 40°C, 48°C is set as the threshold temperature. When the temperature detected within the interval becomes 48°C, the temperature is considered abnormal and the steam is shut down.

[0040] Example 3 The temperature sensor detects the temperature at a time interval of t, and continuously records the adjacent time intervals t1-t nThe temperature difference is calculated by the average value of the temperature difference; At a certain time point t i When the temperature difference exceeds twice the average value, it is determined that there is no material in the granulation bin and the feeder, and the feeder is closed, and the steam control valve of the conditioner is closed.

[0041] Specifically, in this embodiment, the judgment is made based on the temperature change in adjacent time intervals. The time interval for the temperature sensor to detect the temperature is set to 5s, the temperature difference in adjacent time intervals is continuously recorded, and the average value of the temperature difference is recorded. When the temperature difference at a certain time point exceeds twice the average value, the steam valve is immediately closed.

[0042] Example 4 At the same time, close all steam valves in the conditioner. In fact, the steam is turned off as soon as the material in the feeder is emptied. At this time, there is still a part of the tailings running in the conditioner. If the steam is completely turned off at this time, the last tailings may not be fully conditioned.

[0043] In this embodiment, a plurality of steam components are sequentially arranged on the conditioner along its length direction, and each steam component is respectively provided with the steam control valve; When the temperature sensor detects that the outlet temperature of the feeder rises abnormally and rapidly, it is determined that there is no material in the pelletizing bin and the feeder, the feeder is closed, and the steam valve of the steam component closest to the feeder outlet is immediately closed, and then the delay time t is set. 延时 , from the inlet of the conditioner to the outlet of the conditioner, close the steam control valves of the corresponding steam components in sequence.

[0044] Specifically, the steam pipeline arranged along the length of the conditioner is controlled separately, for example, divided into one section or three sections. When the temperature changes abnormally, the steam in the part closest to the feeder outlet is immediately shut off, and then a certain delay is set to close the valves of the second and third sections. In this way, the steam will not enter the feeder and the tailings can continue to be heated.

[0045] Example 5 In this embodiment, in order to achieve more precise control, the granulation bin may retain a material level sensor. When the material has not reached the material level sensor, the temperature sensor performs detection at a first time interval t. When the material reaches the material level sensor, it means that the bin is about to be emptied. At this time, there is still a small amount of material to be transmitted in the feeder. At this time, the temperature sensor increases the detection frequency and performs detection at a second time interval t', which is smaller than the first time interval.

[0046] If the material level sensor does not detect the signal that the material level has reached the bottom, and the temperature sensor still has an abnormal temperature rise, it means that the material level sensor is faulty or an arch has formed in the silo. At this time, the shutdown procedure is still executed.

[0047] The change rule of the pellet mill load is the same as the temperature change rule. After the steam stops, the pellet mill enters the shutdown preparation stage.

[0048] In the normal production stage, the load of the pellet mill is maintained at a high level and fluctuates up and down. After entering the shutdown preparation stage, the incoming material becomes less and less, and the load decreases linearly. After the load stabilizes for a period of time after no load, the machine is shut down in the above order.

[0049] The specific load is related to the specific raw material characteristics, production capacity and other parameters, so no specific examples are given here.

[0050] The above-mentioned implementation modes are only for illustrating the technical features and concepts of the present invention, and their purpose is to enable technicians familiar with this technology in the field to understand the contents of the present invention and implement them. They cannot be used to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit and implementation modes of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for controlling the shutdown of a granulating device, characterized in that: The granulating device comprises a granulating bin, a feeder, a conditioner, a quality preservation device, and a granulating machine host. A temperature sensor is provided at the discharge port of the feeder to obtain temperature data of the discharge port of the feeder; a steam component is provided on the conditioner, and a steam control valve is provided on the steam component; The control method is: During normal production, the temperature of the feeder outlet is T1-T2; the current of the granulator main machine is I1- I2; When the temperature sensor detects that the outlet temperature of the feeder rises abnormally and rapidly, it is determined that there is no material in the granulation bin and the feeder, the feeder is closed, and the steam control valve of the conditioner is closed; Real-time monitoring of the current data of the granulator host; When it is monitored that the current of the granulator main engine drops to the no-load current and remains for 5-10s, it is determined that the granulator main engine is in a no-load state, and the material in the conditioner is drained; the conditioner is closed layer by layer from top to bottom, and then the granulator main engine is closed to complete the shutdown.

2. The granulator shutdown control method according to claim 1, characterized in that: When the temperature sensor detects that the outlet temperature of the feeder rises to T3-T4, T3=1.2 T1, T4=1.2 T2, it is determined that there is no material in the granulation bin and the feeder, and the feeder is closed, and the steam control valve of the conditioner is closed.

3. The granulator shutdown control method according to claim 1, characterized in that: The temperature sensor detects the temperature at a time interval of t, and continuously records the adjacent time intervals t1-t n The temperature difference is calculated by the average value of the temperature difference; At a certain time point t i When the temperature difference exceeds twice the average value, it is determined that there is no material in the granulation bin and the feeder, and the feeder is closed, and the steam control valve of the conditioner is closed.

4. The granulating device shutdown control method according to claim 1, characterized in that: The conditioner is provided with a plurality of steam components in sequence along the length direction thereof, and each steam component is provided with a steam control valve; When the temperature sensor detects that the outlet temperature of the feeder rises abnormally and rapidly, it is determined that there is no material in the pelletizing bin and the feeder, the feeder is closed, and the steam valve of the steam component closest to the feeder outlet is immediately closed, and then the delay time t is set. 延时 , from the inlet of the conditioner to the outlet of the conditioner, close the steam control valves of the corresponding steam components in sequence.

5. The granulator shutdown control method according to claim 3, characterized in that: A material level sensor is arranged on the granulation bin; When the material has not reached the material level sensor, the temperature sensor performs detection at a first time interval t; When the material reaches the material level sensor, it means that the silo is about to be emptied and there is a little material being delivered in the feeder. The temperature sensor increases the detection rate and performs detection at a second time interval t', which is less than the first time interval t; If the material level sensor does not detect the signal that the material level has reached the bottom, and the temperature sensor still shows an abnormal temperature rise, then the material level sensor is faulty, or an arch has formed in the silo, and the machine will shut down.

6. The granulator shutdown control method according to claim 1, characterized in that: The granulation bin, feeder, conditioner, quality preserver and granulator are arranged in order from top to bottom.

7. The granulator shutdown control method according to claim 1, characterized in that: The conditioner comprises at least two conditioners, wherein the conditioner is arranged between the feeder and the quality preserver, and the conditioner is arranged between the feeder and the granulator.

8. The granulating device shutdown control method according to claim 1, characterized in that: During normal production, the feeder outlet temperature T1-T2 is slightly higher than room temperature.

9. The granulator shutdown control method according to claim 1, characterized in that: During normal production, the feeder outlet temperature is 35-45°C.

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