Abnormal combustion monitoring system

Abstract

This system provides an abnormal combustion monitoring system for multiple grain dryers that can quantitatively monitor abnormal combustion in the furnace without relying on the operator's intuition, while keeping costs down. [Solution] The abnormal combustion monitoring system 1 comprises first to eighth inlet pipes 4A to 4H, a measuring tube 5, a gas concentration measuring unit 6, first to eighth on-off valves 7A to 7H, and a control panel 8. This allows for quantitative monitoring of abnormal combustion in the furnace for the first to eighth grain dryers 2A to 2H, without relying on the operator's judgment, while suppressing cost increases.

Description

Technical Field

[0001] The present invention relates to an abnormal combustion monitoring system for monitoring abnormal combustion of a furnace that occurs when drying grains in a grain dryer with hot air from a furnace.

Background Art

[0002] Generally, the drying operation of grains (such as rice and wheat) in a grain drying facility is carried out by a grain dryer. The built-in furnace warms the outside air, and the heated hot air is sent to the grains for drying. Note that fossil fuel (kerosene) is mainly used as the fuel for the furnace. Since the furnace of a newly installed grain dryer is initially adjusted by the manufacturer to achieve complete combustion in accordance with the exhaust side resistance that varies for each facility before the start of use, the operator of the facility can use the grain dryer with confidence.

[0003] However, the furnace of a grain dryer is likely to cause incomplete combustion as it deteriorates over time. It may also occur due to external factors such as deficiencies in peripheral equipment of the grain dryer. When incomplete combustion occurs in the furnace, unburned kerosene (unburned gas) is mixed into the hot air sent to the grains. If this adheres to the grains, the grains will have an odor and are called so-called "off-odor rice," leading to deterioration in quality. Therefore, the operator must regularly check the combustion state of the furnace of the grain dryer during the drying operation. The check for abnormal combustion of the furnace of the grain dryer during the drying operation is carried out by the operator visually observing the state of the flame, or by smelling whether there is an abnormal odor in the hot air sent to the grains, the exhaust after passing through the grains, or the grain sample taken out during drying. The implementation of the check for abnormal combustion of the furnace is carried out by the operator patrolling the grain dryer at regular time intervals.

[0004] As mentioned above, abnormal combustion checks in the furnace of grain dryers during the drying process are judged by the operator using their sight and smell, but there are individual differences in their perception, and quantitative judgments cannot be made. Furthermore, abnormal combustion checks in the furnace are carried out by operators patrolling the grain dryers at regular intervals, so the checks are only fragmentary. In addition, abnormal combustion checks in the furnace conducted by grain dryer manufacturers are performed using equipment that can analyze the gas components of the combustion gases from the furnace, i.e., in the hot air or exhaust, but such gas component analysis equipment is expensive, making it costly for grain dryers that have multiple units installed.

[0005] Currently, the carbon monoxide (CO) concentration generated during incomplete combustion in the furnace is measured using a relatively inexpensive and easy-to-use portable measuring instrument. However, due to the nature of this instrument, the probe cannot withstand continuous use for long periods, and measurement errors accumulate and increase. Therefore, it is necessary to measure multiple grain dryers one by one at certain time intervals, which is inefficient.

[0006] Furthermore, Patent Document 1 describes a drying control device for a grain dryer that can reliably detect abnormal combustion by determining, for example, whether or not there is an abnormality in the combustor based on the pump drive signal. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Application Publication No. 9-196562 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] However, even the drying control device described in Patent Document 1 is prohibitively expensive for grain dryers that have multiple units installed, making its adoption difficult.

[0009] The present invention has been made in view of these points, and aims to provide an abnormal combustion monitoring system that can quantitatively monitor abnormal combustion in furnaces of multiple grain dryers without relying on the operator's judgment, while suppressing cost increases. [Means for solving the problem]

[0010] As a means to solve the above problems, the present invention, as described in claim 1, is an abnormal combustion monitoring system for monitoring abnormal combustion in a furnace that occurs when drying grain in a grain dryer with hot air from the furnace, and is characterized by comprising: a plurality of inlet pipes into which combustion gases from the furnaces of a plurality of grain dryers each flow in; a measuring pipe to which the plurality of inlet pipes converge; a gas concentration measuring unit communicating with the measuring pipe to measure the component concentration of the combustion gases from the furnaces of each grain dryer; on-off valves for opening and closing each of the plurality of inlet pipes; and a control panel that controls the opening and closing of each on-off valve corresponding to each grain dryer, and sequentially guides the combustion gases from the furnaces of each grain dryer to the gas concentration measuring unit via the corresponding inlet pipes and measuring pipes.

[0011] In the invention of claim 1, control from the control panel opens only the on-off valve of the inlet piping into which combustion gas from the furnace of one of the multiple grain dryers flows, and closes all the on-off valves of the inlet piping corresponding to the remaining grain dryers. As a result, the combustion gas flow path of one grain dryer (including the corresponding inlet piping and measuring tube) is connected to the gas concentration measuring unit. The gas concentration measuring unit then measures the component concentration of the combustion gas from the furnace of that grain dryer. Subsequently, control from the control panel opens only the on-off valve of the inlet piping into which combustion gas from the furnace of the next grain dryer flows, connecting the combustion gas flow path of the next grain dryer (including the corresponding inlet piping and measuring tube) to the gas concentration measuring unit. The gas concentration measuring unit then measures the component concentration of the combustion gas from the furnace of that next grain dryer.

[0012] In this way, the control panel sequentially connects the combustion gas flow path of a specific grain dryer among several grain dryers to a gas concentration measurement unit, and the gas concentration of the combustion gas components from the furnace of that specific grain dryer is measured by the gas concentration measurement unit. If there is an abnormality in the combustion gas component concentration from the furnace of a specific grain dryer, the operator is notified of the abnormality by an alarm or other means. This makes it possible to quantitatively monitor abnormal combustion in the furnaces of multiple grain dryers without relying on the operator's judgment, while suppressing cost increases.

[0013] The invention described in claim 2 is characterized in that, in the invention of claim 1, the measuring tube has the function of taking in outside air into the gas concentration measuring unit. In the invention of claim 2, by controlling the on / off valves of each inlet pipe with a control panel, the gas suction pump built into the gas concentration measuring instrument of the gas concentration measuring unit is activated, allowing fresh air from outside to reach the sensor part of the gas concentration measuring instrument of the gas concentration measuring unit through the measuring tube, thereby cleaning the sensor part. This improves the measurement accuracy of the gas concentration measuring instrument.

[0014] The invention described in claim 3 is characterized in that, in the invention of claim 1, the inlet pipe is provided with a condensation trap for capturing condensation that occurs on the inner wall surface of the inlet pipe. As a prerequisite, condensation occurs on the inner wall surface of the inflow pipe due to the temperature difference between the inside (combustion gas) and the outside air. This condensation can cause malfunction of the sensor part of the gas concentration measuring instrument in the gas concentration measuring unit. In view of this situation, the invention of claim 3 can capture the condensation that has formed on the inner wall surface of the inflow pipe with a condensation trap and discharge it to the outside, thereby solving the above-mentioned problem.

[0015] The invention described in claim 4 is characterized in that, in the invention of claim 1, the gas concentration measuring unit includes a dust filter, a flow meter, and a gas concentration measuring device. In the invention of claim 4, the gas concentration measuring unit is equipped with a dust filter and a flow meter in addition to the gas concentration measuring instrument, thereby improving the measurement accuracy of the gas concentration measuring instrument.

[0016] The invention described in claim 5 is characterized in that, in the invention of claim 1, the plurality of grain dryers are arranged in parallel, and the gas concentration measuring unit is placed at approximately the center of each arranged grain dryer. The invention of claim 5 ensures the flow rate of combustion gas necessary for measurement by the gas concentration measuring instrument of the gas concentration measuring unit, and while ensuring the measurement accuracy of the gas concentration measuring instrument, it becomes possible to arrange approximately twice the number of grain dryers relative to the pump capacity of the gas suction pump of the gas concentration measuring instrument, making it efficient.

[0017] The invention described in claim 6 is characterized in that, in the invention of claim 1, the gas concentration measuring unit is configured to issue an alarm when the component concentration of the combustion gas from the furnace of each grain dryer shows an abnormality. In the invention of claim 6, when abnormal combustion occurs in the furnace of each grain dryer, the operator can quickly recognize the abnormality and then promptly perform appropriate maintenance procedures.

[0018] The abnormal combustion monitoring system according to the present invention allows for quantitative monitoring of abnormal combustion in a furnace, without relying on the operator's intuition, while suppressing cost increases. [Brief explanation of the drawing]

[0019] [Figure 1] Figure 1 is a schematic side view of a grain dryer in which an abnormal combustion monitoring system according to an embodiment of the present invention is employed. [Figure 2] Figure 2 is a schematic diagram of an abnormal combustion monitoring system according to an embodiment of the present invention, which includes multiple grain dryers. [Figure 3] Figure 3 is a front view showing the first to eighth condensation traps of an abnormal combustion monitoring system according to an embodiment of the present invention. [Figure 4] FIG. 4 is a flowchart showing the operation of the abnormal combustion monitoring system according to an embodiment of the present invention.

Embodiments for Carrying Out the Invention

[0020] Hereinafter, embodiments for carrying out the present invention will be described in detail based on FIGS. 1 to 4. Referring to FIG. 2, the abnormal combustion monitoring system 1 according to an embodiment of the present invention is particularly provided in grain drying equipment in which a plurality of, for example, eight grain dryers 2A to 2H (a total of eight) are installed, and monitors abnormal combustion of the furnace 18 when drying the grain in the first to eighth grain dryers 2A to 2H with hot air from the furnace 18 (see FIG. 1).

[0021] The abnormal combustion monitoring system 1 according to the present embodiment, referring to FIG. 2, includes first to eighth inflow pipes 4A to 4H into which combustion gases from the furnaces 18 of the first to eighth grain dryers 2A to 2H respectively flow, a measurement pipe 5 to which the first to eighth inflow pipes 4A to 4H are connected (gathered), a gas concentration measurement unit 6 that is connected to the measurement pipe 5 and measures the component concentrations of the combustion gases from the furnaces 18 of the first to eighth grain dryers 2A to 2H, first to eighth on-off valves 7A to 7H that respectively open and close the first to eighth inflow pipes 4A to 4H to allow and block the flow of the combustion gas, and a control panel 8 that controls the opening and closing of the first to eighth on-off valves 7A to 7H corresponding to the first to eighth grain dryers 2A to 2H, and guides the combustion gas from the furnaces 18 of the first to eighth grain dryers 2A to 2H to the gas concentration measurement unit 6 sequentially through the corresponding first to eighth inflow pipes 4A to 4H and the measurement pipe 5.

[0022] In the present embodiment, referring to FIG. 2, the first to eighth grain dryers 2A to 2H are arranged in parallel (in a row) with an interval between them, and eight are arranged. A gas concentration measurement unit 6, which will be described in detail later, is arranged between the fourth grain dryer 2D and the fifth grain dryer 2E. In FIG. 2, there is a large space between the fourth grain dryer 2D and the fifth grain dryer 2E, but this is provided for convenience of explanation. In actuality, the first to eighth grain dryers 2A to 2H are arranged, for example, at equal intervals.

[0023] Referring to Figure 1, the first to eighth grain dryers 2A to 2H each consist of a storage tower 15 for storing grain and a drying tower 16 located below the storage tower 15 for drying the grain. The first to eighth grain dryers 2A to 2H are also equipped with a downstream blower 17 and an upstream furnace 18. Outside air drawn in from the upstream side of the furnace 18 by the blower 17 is heated in the furnace 18 to become hot air, which is then guided through a hot air duct 19 to the drying tower 16, where the grain inside the drying tower 16 is dried. The hot air that has dried the grain in the drying tower 16 passes through the blower 17 and is then discharged outside the machine through an exhaust duct 20. The grain is fed into the first to eighth grain dryers 2A to 2H via a dryer input conveyor 21, sent from the storage tower 15 to the drying tower 16, and dried as described above. The grain is then discharged to the discharge conveyor 23 by the discharge device 22, lifted by the circulating elevator 24, and then fed back into the 1st to 8th grain dryers 2A to 2H via the circulating conveyor 25. This process is repeated several times to dry the grain to a predetermined moisture content. Once the drying is complete, the grain is discharged out of the machine via the dryer discharge conveyor 26.

[0024] Referring to Figures 1 and 2, the first to eighth inlet pipes 4A to 4H are connected to the hot air ducts 19 of the first to eighth grain dryers 2A to 2H, respectively. In this embodiment, the first to eighth inlet pipes 4A to 4H are connected to the hot air ducts 19 of the first to eighth grain dryers 2A to 2H, respectively. However, for example, the first to eighth inlet pipes 4A to 4H can be connected to the combustion gas flow path from the furnace 18 within the first to eighth grain dryers 2A to 2H, such as the furnace 18 of the first to eighth grain dryers 2A to 2H. The first to eighth condensation traps 30A to 30H are located on the first to eighth grain dryer 2A to 2H side of the first to eighth inlet pipes 4A to 4H. In addition, the first to eighth on-off valves 7A to 7H are located on the measuring pipe 5 side of the first to eighth inlet pipes 4A to 4H, which will be described later. Referring also to Figure 3, the first to eighth condensation traps 30A to 30H capture and store condensation that forms on the inner wall surface of the first to eighth inlet pipes 4A to 4H due to the temperature difference between the inside (combustion gas) and the outside air, and discharge it to the outside at an appropriate time.

[0025] Referring to Figures 2 and 3, the first to eighth condensation traps 30A to 30H each include a storage tank 32 for collecting condensation from the first to eighth inlet pipes 4A to 4H, a drain hole 33 extending vertically from the storage tank 32, and an on-off valve 34 (solenoid valve) for opening and closing the drain hole 33. The opening and closing of the on-off valve 34 of the first to eighth condensation traps 30A to 30H is controlled by the control panel 8.

[0026] The opening and closing of the first to eighth on-off valves 7A to 7H are controlled by the control panel 8. Referring to Figure 2, the first to eighth inlet pipes 4A to 4H are each connected to the measuring pipe 5. The measuring pipe 5 extends along the arranged first to eighth inlet pipes 4A to 4H. The measuring pipe 5 has a branch inlet pipe 37 that branches off from its middle section, and this branch inlet pipe 37 is connected to the gas concentration measuring unit 6. The first to eighth inlet pipes 4A to 4H are connected to the gas concentration measuring unit 6 via the measuring pipe 5 and the branch inlet pipe 37. Both longitudinal ends of the measuring pipe 5 are open as fresh air inlets. In short, the measuring pipe 5 has the function of taking in outside air (fresh air) to the gas concentration measuring unit 6. Air inlet on-off valves 39A and 39B (solenoid valves) are located at each fresh air inlet of the measuring pipe 5. The opening and closing of the air inlet valves 39A and 39B are controlled by the control panel 8.

[0027] As in this embodiment, when the suction path from the gas concentration meter 44 of the gas concentration measurement unit 6 to the first or eighth grain dryer 2A or 2H is long, the ninth condensation trap 30I is placed in the branch inlet pipe 37. However, if there are only about two grain dryers, it is not necessary to provide the ninth condensation trap 30I. The configuration and operation of the ninth condensation trap 30I are the same as those of the first to eighth condensation traps 30A to 30H described above. The on / off valve of the ninth condensation trap 30I (not shown in the figure but referred to as reference numeral 34 and described below) is also controlled by the control panel 8. The gas concentration measurement unit 6 includes a dust filter 42, a flow meter 43, and a gas concentration meter 44. These dust filter 42, flow meter 43, and gas concentration meter 44 are in communication with each other. The branch inlet pipe 37 is in communication with the dust filter 42. The dust filter 42 removes dust and debris contained in the combustion gases and fresh air that flow in through the branch inlet pipe 37.

[0028] The flow meter 43 measures the flow rate of combustion gas flowing in from the hot air duct 19 (furnace 18) of the first to eighth grain dryers 2A to 2H via the first to eighth inlet pipes 4A to 4H, the measuring pipe 5, and the branch inlet pipe 37. While the abnormal combustion monitoring system 1 according to this embodiment is operating, the operator can visually check the measurement value of the flow meter 43 to confirm that a predetermined flow rate of combustion gas necessary for measurement is flowing into the gas concentration meter 44. The gas concentration meter 44 measures the component concentration of combustion gas flowing in from the hot air duct 19 (furnace 18) of the first to eighth grain dryers 2A to 2H via the first to eighth inlet pipes 4A to 4H, the measuring pipe 5, and the branch inlet pipe 37 at a predetermined flow rate. The gas concentration meter 44 is equipped with an alarm generating means 46 that issues an alarm if the component concentration of the combustion gas from the hot air duct 19 (furnace 18) of the first to eighth grain dryers 2A to 2H shows an abnormal value. The ON / OFF state of the gas concentration meter 44 is controlled by the control panel 8.

[0029] Furthermore, the gas concentration measuring instrument 44 has a built-in gas suction pump 48. The gas suction pump 48 has the pumping capacity to draw combustion gas from the hot air ducts 19 (furnaces 18) of the first to eighth grain dryers 2A to 2H. In other words, the gas suction pump 48 has the pumping capacity to draw a predetermined flow rate that allows the gas concentration measuring instrument 44 to measure the component concentration of the combustion gas from the hot air ducts 19 of the first to eighth grain dryers 2A to 2H. To put it another way, the pumping capacity of the gas suction pump 48 is set by converting it into the total length obtained by adding the lengths of the branch inlet pipe 37, measuring pipe 5, and the first or eighth inlet pipe 4A or 4H to the first or eighth grain dryer 2A or 2H located furthest from the gas concentration measuring unit 6. The number of first to eighth grain dryers 2A to 2H can be set based on the pumping capacity of the gas suction pump 48.

[0030] In this embodiment, the gas concentration measuring unit 6 is positioned between the fourth grain dryer 2D and the fifth grain dryer 2E, allowing for approximately twice the number of first to eighth grain dryers 2A to 2H relative to the pumping capacity of the gas suction pump 48. The control panel 8 controls the ON / OFF operation of the gas concentration measuring instrument 44 of the gas concentration measuring unit 6, the opening and closing operation of the first to eighth on-off valves 7A to 7H located in the first to eighth inlet pipes 4A to 4H, the opening and closing operation of the air inlet on-off valves 39A and 39B of the measuring tube 5, and the opening and closing operation of the on-off valves 34 provided in the first to ninth condensation traps 30A to 30I. Detailed control of the control panel 8 will be explained when describing the operation of the abnormal combustion monitoring system 1 according to this embodiment.

[0031] Next, the operation of the abnormal combustion monitoring system 1 according to this embodiment will be explained based on Figure 4, with reference to Figures 2 and 3 as appropriate. First, the control panel 8 activates the gas concentration measuring instrument 44 of the gas concentration measuring unit 6 to start operation. Next, an initial cleaning step S0C is performed to clean the sensor part (not shown) of the gas concentration meter 44, as well as the branch inlet pipe 37, the measuring pipe 5, and the first to eighth inlet pipes 4A to 4H. Specifically, in the initial cleaning step S0C, the control panel 8 controls the first to eighth on-off valves 7A to 7H of the first to eighth inlet pipes 4A to 4H, which are connected to the hot air duct 19 of the first to eighth grain dryers 2A to 2H. In addition, the air inlet on-off valve 39A on one longitudinal end of the measuring pipe 5 (towards the first to fourth grain dryers 2A to 2D) is opened, and the air inlet on-off valve 39B on the other longitudinal end (towards the fifth to eighth grain dryers 2E to 2H) is closed.

[0032] Then, the gas suction pump 48 of the gas concentration measuring instrument 44 of the gas concentration measuring unit 6 draws in outside air (fresh air) from the fresh air inlet, which is open at one end of the measuring tube 5 in the longitudinal direction → measuring tube 5 → branch inlet pipe 37 → dust filter 42 of the gas concentration measuring unit 6 → flow meter 43 → gas concentration measuring instrument 44. In this way, the sensor part of the gas concentration measuring instrument 44 can be cleaned by the outside air (fresh air).

[0033] After a certain period of time, the air inlet valve 39A at one end of the measuring tube 5 in the longitudinal direction (towards the 1st to 4th grain dryers 2A to 2D) is closed, and the air inlet valve 39B at the other end in the longitudinal direction (towards the 5th to 8th grain dryers 2E to 2H) is opened. Then, the gas suction pump 48 of the gas concentration measuring instrument 44 of the gas concentration measuring unit 6 draws in outside air (fresh air) from the fresh air inlet at the other end of the measuring tube 5 in the longitudinal direction → measuring tube 5 → branch inlet pipe 37 → dust filter 42 of the gas concentration measuring unit 6 → flow meter 43 → gas concentration measuring instrument 44. This allows the sensor part of the gas concentration measuring instrument 44 to be cleaned by the outside air (fresh air). At this time, the control panel 8 opens the on-off valves 34 of the first to ninth condensation traps 30A to 30I, emptying the storage tanks 32 of the first to ninth condensation traps 30A to 30I.

[0034] Next, an abnormal combustion determination step S1 is performed to determine whether or not abnormal combustion is occurring in the combustion gas from the furnace 18 of the first grain dryer 2A, one of the first to eighth grain dryers 2A to 2H. The first grain dryer 2A is located on the far right in Figure 2. Specifically, the control panel 8 opens the first on-off valve 7A of the first inlet pipe 4A, which communicates with the hot air duct 19 of the first grain dryer 2A, and closes all of the second to eighth on-off valves 7B to 7H of the second to eighth inlet pipes 4B to 4H, which communicate with the hot air ducts 19 of the remaining second to eighth grain dryers 2B to 2H, respectively. In addition, the on-off valves 34 of the first to ninth condensation traps 30A to 30I are closed. Furthermore, the air inlet on-off valves 39A and 39B of the measuring tube 5 are closed. As a result, the hot air duct 19 of the first grain dryer 2A and the gas concentration measuring unit 6 are connected via the first inlet pipe 4A and the measuring tube 5.

[0035] Next, the combustion gas from the furnace 18 of the first grain dryer 2A is drawn in by the gas suction pump 48 of the gas concentration measuring instrument 44, and guided through the hot air duct 19 → first inlet pipe 4A → measuring pipe 5 → branch inlet pipe 37 to the gas concentration measuring unit 6. In the gas concentration measuring unit 6, the combustion gas from the hot air duct 19 of the first grain dryer 2A is guided through the dust filter 42 and flow meter 43 to the gas concentration measuring instrument 44. Note that when the combustion gas from the hot air duct 19 of the first grain dryer 2A passes through the dust filter 42, dust and debris contained in the combustion gas are removed. The operator also confirms that the combustion gas from the first grain dryer 2A has passed through the flow meter 43 and that the required flow rate of combustion gas for measurement is flowing into the gas concentration measuring instrument 44 by visually checking the measurement value of the flow meter 43.

[0036] Then, the gas concentration meter 44 measures the component concentration of the combustion gas from the hot air duct 19 of the first grain dryer 2A, and the process proceeds to the next step S1C. If the measurement result from the gas concentration meter 44 is determined to be an abnormal value, an alarm is issued by the alarm generating means 46. After that, the operator stops the drying process of all the first to eighth grain dryers 2A to 2H, and performs maintenance work, etc., in particular, to ensure that the combustion gas from the furnace 18 of the first grain dryer 2A becomes normal.

[0037] Next, a primary cleaning step S1C is performed to clean the sensor part of the gas concentration meter 44, as well as the branch inlet pipe 37, the measuring pipe 5, and the first to fourth inlet pipes 4A to 4D. Specifically, in the primary cleaning step S1C, the control panel 8 controls the first to eighth on-off valves 7A to 7H of the first to eighth inlet pipes 4A to 4H to close them all. In addition, the air inlet on-off valve 39A on one longitudinal end of the measuring pipe 5 (towards the first to fourth grain dryers 2A to 2D) is opened, and the air inlet on-off valve 39B on the other longitudinal end (towards the fifth to eighth grain dryers 2E to 2H) is closed.

[0038] Then, the gas suction pump 48 of the gas concentration measuring instrument 44 of the gas concentration measuring unit 6 draws in outside air (fresh air) from the fresh air inlet on one longitudinal end of the measuring tube 5 → measuring tube 5 → branch inlet pipe 37 → dust filter 42 of the gas concentration measuring unit 6 → flow meter 43 → gas concentration measuring instrument 44, and the outside air (fresh air) cleans the sensor part of the gas concentration measuring instrument 44. At the same time, the control panel 8 opens only the on-off valves 34 of the first to fourth and ninth condensation traps 30A to 30D and 30I. Then, the condensation that had accumulated in the storage tanks 32 of the first to fourth and ninth condensation traps 30A to 30D and 30I, in particular the condensation that had accumulated in the storage tank 32 of the first condensation trap 30A, falls to the outside through the drain hole 33.

[0039] Next, an abnormal combustion determination step S2 is performed to determine whether or not abnormal combustion is occurring in the combustion gas from the furnace 18 of the second grain dryer 2B. The second grain dryer 2B is located second from the right end in Figure 2. Specifically, the control panel 8 closes the air inlet valves 39A and 39B of the measuring tube 5. In addition, all the on-off valves 34 of the first to ninth condensation traps 30A to 30I are closed. Furthermore, only the second on-off valve 7B of the second inflow pipe 4B, which communicates with the hot air duct 19 of the second grain dryer 2B, is opened. As a result, the hot air duct 19 of the second grain dryer 2B and the gas concentration measuring unit 6 are connected via the second inflow pipe 4B and the measuring tube 5. Then, the combustion gas from the furnace 18 of the second grain dryer 2B is guided to the gas concentration measurement unit 6 via the hot air duct 19 → second inlet pipe 4B → measuring pipe 5 → branch inlet pipe 37, where the component concentration of the combustion gas from the hot air duct 19 of the second grain dryer 2B is measured by the gas concentration measuring instrument 44, and the process proceeds to the next step S1C. If the measurement result by the gas concentration measuring instrument 44 is determined to be an abnormal value, an alarm is issued by the alarm generating means 46.

[0040] Next, the primary cleaning step S1C is performed again. The specific steps of this primary cleaning step S1C have been described above, so their explanation is omitted here. In the subsequent abnormal combustion steps S3 to S8, the combustion gas from the hot air ducts 19 of the third to eighth grain dryers 2C to 2H is sequentially guided to the gas concentration measuring instrument 44 of the gas concentration measuring unit 6 via the third to eighth inlet pipes 4C to 4H, the measuring pipe 5, and the branch inlet pipe 37 to determine whether or not abnormal combustion is occurring. Basically, the same steps as the abnormal combustion determination step S1 for the furnace 18 of the first grain dryer 2A and the abnormal combustion determination step S2 for the furnace 18 of the second grain dryer 2B described above are performed. The primary cleaning step S1C is performed between the abnormal combustion determination step S1 for the furnace 18 of the first grain dryer 2A and the abnormal combustion determination step S2 for the furnace 18 of the second grain dryer 2B, between the abnormal combustion determination step S2 for the furnace 18 of the second grain dryer 2B and the abnormal combustion determination step S3 for the furnace 18 of the third grain dryer 2C, between the abnormal combustion determination step S3 for the furnace 18 of the third grain dryer 2C and the abnormal combustion determination step S4 for the furnace 18 of the fourth grain dryer 2D, and between the abnormal combustion determination step S4 for the furnace 18 of the fourth grain dryer 2D and the abnormal combustion determination step S5 for the furnace 18 of the fifth grain dryer 2E.

[0041] On the other hand, the secondary cleaning step S2C is performed between the abnormal combustion determination step S5 for the furnace 18 of the fifth grain dryer 2E and the abnormal combustion determination step S6 for the furnace 18 of the sixth grain dryer 2F, between the abnormal combustion determination step S6 for the furnace 18 of the sixth grain dryer 2F and the abnormal combustion determination step S7 for the furnace 18 of the seventh grain dryer 2G, between the abnormal combustion determination step S7 for the furnace 18 of the seventh grain dryer 2G and the abnormal combustion determination step S8 for the furnace 18 of the eighth grain dryer 2H, and between the abnormal combustion determination step S8 for the furnace 18 of the eighth grain dryer 2H and the continuous operation feasibility determination step S9, which will be described later.

[0042] In the secondary cleaning step S2C, the air inlet valve 39B on the other end of the measuring tube 5 in the longitudinal direction (towards grain dryers 2E to 2H) is opened, and the air inlet valve 39A on one end of the measuring tube 5 in the longitudinal direction (towards grain dryers 2A to 2D) is closed. Then, the gas suction pump 48 of the gas concentration measuring instrument 44 of the gas concentration measuring unit 6 draws in outside air (fresh air) from the fresh air inlet on the other end of the measuring tube 5 in the longitudinal direction → measuring tube 5 → branch inlet pipe 37 → dust filter 42 of the gas concentration measuring unit 6 → flow meter 43 → gas concentration measuring instrument 44, and the sensor part of the gas concentration measuring instrument 44 is cleaned by the outside air (fresh air). At the same time, the control panel 8 controls the opening of the valves 34 of the 5th to 9th condensation traps 30E to 30I. Then, the condensation that had accumulated in the storage tanks 32 of the 5th to 9th condensation traps 30E to 30I drips out through the drain holes 33.

[0043] In this series of processes, abnormal combustion detection steps S1 to S8 are sequentially performed on the furnaces 18 of the first to eighth grain dryers 2A to 2H, and a primary or secondary cleaning step S1C or S2C is performed between the abnormal combustion detection steps S1 to S8 for the furnaces 18 of the first to eighth grain dryers 2A to 2H. If no abnormal combustion is detected for the furnace 18 of a particular grain dryer 2A to 2H, the abnormal combustion detection steps S1 to S8 for the furnaces 18 of the first to eighth grain dryers 2A to 2H and the primary or secondary cleaning step S1C or S2C are performed consecutively.

[0044] Furthermore, after the abnormal combustion determination step S8 for the furnace 18 of the 8th grain dryer 2H, a secondary cleaning step S2C is performed and completed. Then, the control panel 8 controls the system to perform a continuous operation feasibility determination step S9. If the continuous operation feasibility determination step S9 determines that continuous operation is permitted (Yes), the system returns to the abnormal combustion determination step S1 for the furnace 18 of the 1st grain dryer 2A, and the series of processes described above (steps S1-S9, S1C, and S2C) are repeated. This embodiment is used when the series of processes (steps S1-S9, S1C, and S2C) are to be repeatedly performed continuously while the 1st to 8th grain dryers 2A-2H are in operation. On the other hand, if the continuous operation feasibility determination step S9 determines that continuous operation is not permitted (No), the series of processes (steps S1-S9, S1C, and S2C) can be terminated. In this embodiment, abnormal combustion is determined sequentially for the furnaces 18 of the first to eighth grain dryers 2A to 2H in the abnormal combustion determination steps S1 to S8, but the order is not limited to this.

[0045] As described above, the abnormal combustion monitoring system 1 according to this embodiment includes, in particular, first to eighth inlet pipes 4A to 4H into which combustion gases from the furnaces 18 of the first to eighth grain dryers 2A to 2H respectively flow; a measuring pipe 5 through which the first to eighth inlet pipes 4A to 4H are connected (combined); a gas concentration measuring unit 6 communicating with the measuring pipe 5 to measure the component concentrations of the combustion gases from the furnaces 18 of the first to eighth grain dryers 2A to 2H; first to eighth on-off valves 7A to 7H that open and close the first to eighth inlet pipes 4A to 4H respectively; and a control panel 8 that controls the opening and closing of the first to eighth on-off valves 7A to 7H corresponding to the first to eighth grain dryers 2A to 2H, and sequentially guides the combustion gases from the furnaces 18 of the first to eighth grain dryers 2A to 2H to the gas concentration measuring unit 6 via the corresponding first to eighth inlet pipes 4A to 4H and measuring pipe 5.

[0046] Then, under control from the control panel 8, the gas concentration measuring unit 6 is sequentially connected to a specific unit among the 1st to 8th grain dryers 2A to 2H, for example, the 1st grain dryer 2A's hot air duct 19, and the gas concentration measuring unit 6 measures the component concentration of the combustion gas from the furnace 18 of the 1st grain dryer 2A. If the component concentration of the combustion gas from the 1st grain dryer 2A is abnormal, the alarm generating means 46 issues an alarm to notify the operator of the abnormality. In this way, the combustion gas from the furnaces 18 of the 1st to 8th grain dryers 2A to 2H (multiple units) can be monitored by a single gas concentration measuring unit 6, which helps to suppress cost increases and allows for quantitative monitoring of abnormal combustion in the furnaces 18 of the 1st to 8th grain dryers 2A to 2H without relying on the operator's judgment.

[0047] Furthermore, in the abnormal combustion monitoring system 1 according to this embodiment, the measuring tube 5 has the function of taking in outside air (fresh air) to the gas concentration measuring unit 6. Then, under control by the control panel 8, the first to eighth on-off valves 7A to 7H of the first to eighth inlet pipes 4A to 4H are all closed, and the air inlet on-off valves 39A and 39B are opened and closed to activate the gas concentration measuring instrument 44 of the gas concentration measuring unit 6. By activating the gas suction pump 48 built into the gas concentration measuring instrument 44, outside air (fresh air) reaches the sensor part of the gas concentration measuring instrument 44 of the gas concentration measuring unit 6 via the measuring tube 5, and the sensor part can be cleaned. This improves the measurement accuracy of the gas concentration measuring instrument 44.

[0048] Furthermore, in the abnormal combustion monitoring system 1 according to this embodiment, the first to eighth inlet pipes 4A to 4H are equipped with first to eighth condensation traps 30A to 30H that capture condensation that occurs on the inner wall surface of the first to eighth inlet pipes 4A to 4H. This makes it possible to suppress malfunctions of the sensor part of the gas concentration measuring instrument 44 due to condensation.

[0049] Furthermore, in the abnormal combustion monitoring system 1 according to this embodiment, the gas concentration measurement unit 6 is equipped with a dust filter 42 and a flow meter 43 in addition to the gas concentration meter 44. The dust filter 42 can remove dust and debris contained in the combustion gas and outside air (fresh air). Also, while the abnormal combustion monitoring system 1 is operating, the operator can visually check the measured value of the flow meter 43 to confirm that the predetermined flow rate of combustion gas necessary for measurement is flowing into the gas concentration meter 44. This improves the measurement accuracy of the gas concentration meter 44.

[0050] Furthermore, in the abnormal combustion monitoring system 1 according to this embodiment, the gas concentration measurement unit 6 is configured to issue an alarm when the component concentration of the combustion gas from the furnaces 18 of the first to eighth grain dryers 2A to 2H shows an abnormality. This allows the operator to quickly recognize the abnormality when abnormal combustion occurs in the furnaces 18 of the first to eighth grain dryers 2A to 2H, and then promptly carry out appropriate maintenance work. In addition, by issuing an alarm and notifying the operator when the component concentration of the combustion gas from the furnaces 18 of the first to eighth grain dryers 2A to 2H shows an abnormality, it is extremely effective in suppressing quality deterioration and providing work support in response to the recent decline in technical capabilities and the shortage of successors.

[0051] Furthermore, in the abnormal combustion monitoring system 1 according to this embodiment, the first to eighth grain dryers 2A to 2H, the first to eighth inlet pipes 4A to 4H including the first to eighth on-off valves 7A to 7H, and the first to eighth condensation traps 30A to 30H are treated as one unit, and the first to eighth inlet pipes 4A to 4H are connected to the measuring pipe 5. This reduces the occupied space and makes it very easy and effective to install, especially when adding the abnormal combustion monitoring system 1 according to this embodiment during after-sales work.

[0052] Furthermore, in the abnormal combustion monitoring system 1 according to this embodiment, a gas concentration measuring unit 6 is placed between the fourth grain dryer 2D and the fifth grain dryer 2E. This makes it possible to place approximately twice the number of grain dryers 2A to 2H relative to the pump capacity of the gas suction pump 48 of the gas concentration measuring unit 6 (the pump capacity converted to the total length (including pipe diameter) of the branch inlet pipe 37, measuring pipe 5, and the first or eighth inlet pipe 4A or 4H up to the first or eighth grain dryer 2A or 2H located furthest from the gas concentration measuring unit 6), thus increasing efficiency.

[0053] Furthermore, in the abnormal combustion monitoring system 1 according to this embodiment, if the operator separately records the gas concentration and the adjustment status of the furnace 18 during the operation of the first to eighth grain dryers 2A to 2H each year, the degree of deterioration of the furnace 18 over time (degree of deterioration progression) can be determined early, and a plan for replacing the furnace 18 can be made in advance.

[0054] In this embodiment, the abnormal combustion monitoring system 1 monitors abnormal combustion in the furnaces 18 of all eight grain dryers 2A to 2H. However, the abnormal combustion monitoring system 1 according to this embodiment may also be used when monitoring abnormal combustion in the furnaces 18 of two to seven or nine or more grain dryers. [Explanation of Symbols]

[0055] 1. Abnormal combustion monitoring system, 2A-2H: 1st to 8th grain dryers, 4A-4H: 1st to 8th inlet piping, 5. Measuring tube, 6. Gas concentration measuring unit, 7A-7H: 1st to 8th on / off valves, 8. Control panel, 18. Furnace, 30A-30I: 1st to 9th condensation traps, 42. Dust filter, 43. Flow meter, 44. Gas concentration measuring instrument, 46. Alarm generation means

Claims

1. An abnormal combustion monitoring system for monitoring abnormal combustion in a furnace that occurs when drying grain in a grain dryer with hot air from the furnace, Multiple inlet pipes into which combustion gases from the furnaces of multiple grain dryers flow, A measuring pipe into which the multiple inflow pipes mentioned above converge, A gas concentration measuring unit, which communicates with the measuring tube, measures the component concentrations of combustion gases from the furnaces of each grain dryer. Each of the aforementioned multiple inlet pipes has an on / off valve that opens and closes, A control panel that controls the opening and closing of each on-off valve corresponding to each grain dryer, and sequentially guides the combustion gas from the furnace of each grain dryer to the gas concentration measuring unit via the corresponding inflow pipe and measuring pipe, An abnormal combustion monitoring system characterized by comprising the following features.

2. The abnormal combustion monitoring system according to claim 1, characterized in that the measuring tube has the function of taking in outside air to the gas concentration measuring unit.

3. The abnormal combustion monitoring system according to claim 1, characterized in that the inlet pipe is provided with a condensation trap for capturing condensation that occurs on the inner wall surface of the inlet pipe.

4. The abnormal combustion monitoring system according to claim 1, characterized in that the gas concentration measurement unit includes a dust filter, a flow meter, and a gas concentration measuring instrument.

5. The abnormal combustion monitoring system according to claim 1, characterized in that the plurality of grain dryers are arranged in parallel, and the gas concentration measuring unit is placed at approximately the center of each arranged grain dryer.

6. The abnormal combustion monitoring system according to claim 1, characterized in that the gas concentration measuring unit is configured to issue an alarm when the component concentration of the combustion gas from the furnace of each grain dryer shows an abnormality.

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