A method for precisely controlling the temperature of a tobacco feed tank liquid

Abstract

The present application provides a kind of tobacco feed tank liquid temperature precision control method, comprising: the sealing interlayer of feed tank is connected with heating steam pipeline, the sealing interlayer of feed tank is sent into steam for heating steam pipeline, to heat the liquid in feed tank;The heating steam pipeline is equipped with steam film valve and quick on-off valve, to control the heating steam amount that heating steam pipeline is transported to feed tank by the opening degree value of steam film valve and quick on-off valve;Determine whether there is liquid in feed tank, if yes, obtain the residual amount of liquid in tank and actual liquid temperature;According to the residual amount of liquid in tank, open and close formula control steam film valve and quick on-off valve is carried out, in the form of steam pressure decompression, temperature precision control is carried out.The present application can accurately control steam to heat feed tank, improve the stability and accuracy of liquid temperature control.

Description

Technical Field

[0001] This invention relates to the field of material liquid temperature control technology in tobacco feeding, and in particular to a method for precise control of the material liquid temperature in a tobacco feeding tank. Background Technology

[0002] The tobacco processing feeder is a device in the tobacco processing industry that adds liquid to atomized tobacco sheets. The feed tank's function is to store the liquid and maintain a constant liquid temperature. The feeder tank temperature is collected by a temperature sensor, and the tank temperature is controlled by the opening and closing of a steam on / off valve. Steam enters the sealed jacket around the tank, indirectly heating the liquid with the heat from the tank wall. When there is a lot of liquid in the tank, the heating process is relatively slow. When there is a little liquid in the tank, heating is rapid, which can easily lead to overheating. Furthermore, due to the deepening research and production of new types of tobacco (heat-not-burn type) in recent years, the requirements for the temperature control of the liquid in the feeder tank of new tobacco production lines have become increasingly stringent. Older or improved equipment can no longer meet the requirements for precise temperature control. Due to the mechanical structure of the feeder tank, the temperature control of the liquid in the tank is a unidirectional control, not a bidirectional control. The valve's opening and closing determines the amount of steam added. All the heat from the steam is transferred to the feed tank and the feed liquid, while excess heat is stored on the steam pipe wall of the feed tank and cannot be dissipated. This inherent characteristic of the feed liquid temperature control in the feed tank dictates that it can only be heated rapidly, not cooled quickly. New tobacco products require specific chemical properties in their feed liquid, prohibiting overheating and ensuring it remains consistently stable within a narrow range of the process-set temperature. Furthermore, another difficulty in achieving stable control is the inability to accurately measure the feed liquid level in the feed tank of existing feeders. New tobacco products often use automatic dispensing, and the common method of estimating the liquid level based on level gauge measurements has significant errors, easily leading to temperature control failure and affecting product quality. Therefore, how to achieve stable temperature control through steam regulation of the feed liquid within the tank is of great importance. Summary of the Invention

[0003] This invention provides a method for precise temperature control of tobacco feeding tank liquid, which solves the problems existing in the temperature control of feeding tank liquid in tobacco processing, and can accurately control the heating of the tank by steam, thereby improving the stability and accuracy of liquid temperature control.

[0004] To achieve the following objectives, the present invention provides the following technical solutions:

[0005] A method for precise temperature control of tobacco feeding tank liquid includes:

[0006] A heating steam pipeline is connected to the sealing jacket of the feeding tank. The heating steam pipeline is used to supply steam to the sealing jacket of the feeding tank to heat the liquid in the feeding tank.

[0007] The heating steam pipeline is equipped with a steam diaphragm valve and a quick-on / off valve, so as to control the amount of heating steam delivered by the heating steam pipeline to the feeding tank by the opening value of the steam diaphragm valve and the quick-on / off valve;

[0008] Determine if there is liquid in the feeding tank. If so, obtain the remaining amount of liquid in the tank and the actual temperature of the liquid.

[0009] The opening and closing of the steam diaphragm valve and the quick-on / off valve are controlled according to the remaining liquid volume in the tank using a zoned formula, and the temperature is precisely controlled by reducing the steam pressure.

[0010] Preferably, obtaining the remaining amount of liquid in the tank includes:

[0011] The remaining amount of liquid in the tank is calculated using the formula G = B * K + X, where B is the total weight of the material produced in the previous process, K is the feeding ratio, X is the empirical value of the remaining amount of liquid after discharge, and G is the theoretical value of the remaining amount of liquid in the tank.

[0012] Preferably, the step of obtaining the remaining amount of liquid in the tank further includes:

[0013] During production, the liquid material in the feeder's tank is sprayed into the feed cylinder and applied to the material. The remaining amount of liquid material in the tank is calculated according to the formula Y = GF = B * K + XF, where F is the total mass flow rate accumulated by the feeder flow meter.

[0014] Preferably, the step of controlling the opening and closing of the steam diaphragm valve and the quick-connect valve according to the residual amount of liquid in the tank using a zoned formula includes:

[0015] A first weight threshold (eight1), a second weight threshold (weight2), and a third weight threshold (weight3) are established to determine the remaining amount of liquid in the tank within the corresponding zone, thereby calculating the opening value of the corresponding steam diaphragm valve. Where weight3... <weight2<weight1;

[0016] The opening value of the steam diaphragm valve is correlated with the remaining amount of liquid, thereby controlling the steam pressure based on the temperature of the liquid in the tank to improve the accuracy of temperature control.

[0017] Preferably, the relationship between the opening value of the steam diaphragm valve and the remaining amount of liquid is constructed by:

[0018] The opening value Va of the steam diaphragm valve is calculated based on the remaining liquid volume Y, using the following formula:

[0019] Preferred options also include:

[0020] The opening time TON2 and closing time TOFF2 of the quick-on / off valve are calculated based on the actual temperature Tt of the liquid. Then, the quick-on / off valve is repeatedly opened and closed in a timed manner. Finally, the opening and closing of the quick-on / off valve is controlled in the form of a fixed value pulse wave, so that the temperature of the liquid in the tank is stabilized to the process set value Ttemp.

[0021] Preferred options also include:

[0022] Obtain production batch information and the standard value of the process temperature maintained in the feed tank corresponding to the production batch information;

[0023] Determine whether the main body of the feeder cylinder and the feed tank are both in a standby, fault-free state. If so, start temperature control of the liquid in the tank until the process temperature standard value is reached; otherwise, return to wait until the production conditions are met.

[0024] Preferred options also include:

[0025] With the quick-on / off valve closed, slowly open the steam diaphragm valve to 100%, and then switch the quick-on / off valve on and off in a timed manner, ensuring that the opening time of the quick-on / off valve is a fixed value TON1 and the closing time of the quick-on / off valve is a fixed value TFF1. Then, repeatedly open and close the quick-on / off valve in a timed manner to eventually form a fixed value pulse wave to control the opening and closing of the quick-on / off valve, so that the temperature of the feed liquid is heated to the process set value.

[0026] Preferred options also include:

[0027] Maintain the steam diaphragm valve at 100% opening, and open the quick-start valve in a timed manner to ensure that the quick-start valve is open for the set time value TON3. Then immediately close the quick-start valve and the steam diaphragm valve to control the upward trend of the liquid temperature in the tank until the liquid temperature in the tank reaches the set maximum value.

[0028] This invention provides a method for precise temperature control of tobacco feeding tank liquid. The method uses the residual steam entering the tank and the actual liquid temperature to adjust the opening of the steam diaphragm valve and the quick-on / off valve on the heating steam pipeline connected to the feeding tank, thereby controlling the liquid temperature in the feeding tank. This solves the problems existing in the temperature control of the liquid in existing tobacco feeding tanks, and can accurately control the heating of the tank by steam, improving the stability and accuracy of liquid temperature control. Attached Figure Description

[0029] To more clearly illustrate the specific embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below.

[0030] Figure 1 This is a schematic diagram of a method for precise temperature control of tobacco feeding tank liquid provided by the present invention.

[0031] Figure 2 This is a schematic diagram of the feeding tank and heating pipeline provided in an embodiment of the present invention. Detailed Implementation

[0032] To enable those skilled in the art to better understand the embodiments of the present invention, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and implementation methods.

[0033] To address the problems existing in the temperature control of the feed liquid in existing tobacco feeding tanks, this invention provides a method for precise temperature control of the feed liquid in tobacco feeding tanks. This method solves the problems existing in the temperature control of the feed liquid in existing tobacco feeding tanks, and can accurately control the heating of the tank by steam, thereby improving the stability and accuracy of the feed liquid temperature control.

[0034] like Figure 1 and Figure 2 As shown, a method for precise temperature control of tobacco feeding tank liquid includes:

[0035] S1: A heating steam pipeline is connected to the sealing jacket of the feeding tank. The heating steam pipeline is used to supply steam to the sealing jacket of the feeding tank to heat the liquid in the feeding tank.

[0036] S2: The heating steam pipeline is equipped with a steam diaphragm valve and a quick-on / off valve, so as to control the amount of heating steam delivered by the heating steam pipeline to the feeding tank by the opening value of the steam diaphragm valve and the quick-on / off valve.

[0037] S3: Determine whether there is liquid in the feeding tank. If so, obtain the remaining amount of liquid in the tank and the actual temperature of the liquid.

[0038] S4: Based on the remaining amount of liquid in the tank, the opening and closing of the steam diaphragm valve and the quick-on / off valve are controlled in a zoned formula to achieve precise temperature control in the form of steam pressure reduction.

[0039] Specifically, such as Figure 2As shown, this control method requires that the heating steam pipeline of the feeding tank be equipped with a quick-on / off valve (on / off control), a steam diaphragm valve (percentage opening control), and other necessary components for the steam pipeline. It ensures that the dead zone of the steam diaphragm valve is less than 3%, meaning that when the steam diaphragm valve opening is greater than 3%, there must be a flow of medium entering the feeding tank for heating the liquid. The presence of liquid in the feeding tank can be determined by a level switch, level gauge, or manual confirmation. If liquid is present, the process continues; otherwise, it returns to wait until production conditions are met. The opening values ​​of the steam diaphragm valve and the quick-on / off valve control the amount of heating steam delivered to the feeding tank by the heating steam pipeline. The opening and closing of the steam diaphragm valve and the quick-on / off valve are controlled by a zoned formula based on the remaining liquid in the tank, achieving precise temperature control through steam pressure reduction. This method can accurately control the heating of the tank by steam, improving the stability and accuracy of liquid temperature control.

[0040] Furthermore, obtaining the remaining amount of liquid in the tank includes:

[0041] The remaining amount of liquid in the tank is calculated using the formula G = B * K + X, where B is the total weight of the material produced in the previous process, K is the feeding ratio, X is the empirical value of the remaining amount of liquid after discharge, and G is the theoretical value of the remaining amount of liquid in the tank.

[0042] In practical applications, before temperature control of the molten material in the feeding tank, it is necessary to estimate the calculation method for the molten material remaining in the feeding machine's tank. First, obtain the total weight B of the material produced in the previous process, then multiply it by the feeding ratio K to obtain the theoretical weight of molten material to be fed. Add a fixed weight value X (an empirical value for the remaining amount of molten material after discharge), and finally calculate the theoretical value G of the molten material remaining in the feeding machine's tank before production through the equipment controller.

[0043] After measuring the weight of the material in the feed tank, feeding and production are permitted. Once production begins, the liquid material in the feeder's feed tank is sprayed into the feed cylinder and applied to the material, causing the liquid material in the feeder's feed tank to gradually decrease.

[0044] Furthermore, the method of obtaining the remaining amount of liquid in the tank also includes:

[0045] During production, the liquid material in the feeder's tank is sprayed into the feed cylinder and applied to the material. The remaining amount of liquid material in the tank is calculated according to the formula Y = GF = B * K + XF, where F is the total mass flow rate accumulated by the feeder flow meter.

[0046] Furthermore, the step of controlling the opening and closing of the steam diaphragm valve and the quick-connect valve according to the residual amount of liquid in the tank using a zoned formula includes:

[0047] A first weight threshold (eight1), a second weight threshold (weight2), and a third weight threshold (weight3) are established to determine the remaining amount of liquid in the tank within the corresponding zone, thereby calculating the opening value of the corresponding steam diaphragm valve. Where weight3... <weight2<weight1;

[0048] The opening value of the steam diaphragm valve is correlated with the remaining amount of liquid, thereby controlling the steam pressure based on the temperature of the liquid in the tank to improve the accuracy of temperature control.

[0049] Furthermore, constructing the correspondence between the opening value of the steam diaphragm valve and the remaining amount of liquid includes:

[0050] The opening value Va of the steam diaphragm valve is calculated based on the remaining liquid volume Y, using the following formula:

[0051]

[0052] In the precise temperature control method for the tobacco feeding tank, the percentage adjustment of the steam diaphragm valve opening effectively reduces steam pressure. If the liquid level is high, the Y value is large, resulting in a large steam diaphragm valve opening. This reduces the need for significant steam pressure reduction, allowing more steam to enter under the same conditions. Conversely, if the liquid level is low, the Y value is small, requiring a small steam diaphragm valve opening. This necessitates steam pressure reduction, resulting in less steam entering under the same conditions. By linking the diaphragm valve opening to the remaining liquid level in the tank and implementing zoned formulaic control based on this remaining level, precise temperature control is achieved through steam pressure reduction.

[0053] The method further includes: calculating the opening time TON2 and closing time TOFF2 of the quick-on / off valve based on the actual temperature Tt of the liquid, and then repeatedly opening and closing the quick-on / off valve in a timed manner, and finally controlling the opening and closing of the quick-on / off valve in the form of a fixed value pulse wave, so that the temperature of the liquid in the tank is stabilized to the process set value Ttemp.

[0054] In practical applications, the opening time TON2 of the quick-on / off valve is calculated based on the actual temperature Tt of the feed liquid:

[0055]

[0056] Wherein, TON2 is the fixed pulse wave activation time length, Tt is the actual liquid temperature value, YU2 is temperature threshold 2, YU3 is temperature threshold 3, Ttemp is the process setting value of the liquid temperature in the tank, Tthreshold1 is the pulse activation time threshold 1, Tthreshold2 is the pulse activation time threshold 2, and Tthreshold3 is the pulse activation time threshold 3.

[0057] The temperature threshold relationship is: 0 < YU2 < YU3. When the actual liquid temperature is close to or exceeds the process setpoint (Tt > (Temp - YU2), heating is only required by the residual steam in the tank, and the quick-on / off valve does not need to be opened. When the actual liquid temperature is less than (Temp - YU2) but greater than (Temp - YU3), the opening of the quick-on / off valve is controlled by a fixed-value pulse. Time threshold 2 is a fixed value, and time threshold 1 is the coefficient of the product. The opening time of the fixed-value pulse wave is constructed using a linear proportional function. When the actual liquid temperature is less than (Temp - YU3), if the opening time calculated based on the above linear proportional function is too small, the quick-on / off valve will not respond. Therefore, a fixed-value time threshold 3 is selected as the opening time of the fixed-value pulse wave.

[0058] Calculate the closing time TOFF2 of the quick-closing valve based on the actual temperature Tt of the feed liquid:

[0059]

[0060] Wherein, TFF2 is the fixed pulse wave shut-off time length, Tt is the actual liquid temperature value, YU3 is the temperature threshold 3, Ttemp is the process set value of the liquid temperature in the tank, Tthreshold4 is the pulse shut-off time threshold 4, and Tthreshold5 is the pulse shut-off time threshold 5.

[0061] The time threshold relationship is: 0 < T threshold5 <T threshold4 When the actual liquid temperature is less than (Temp-YU2) but greater than (Temp-YU3), the quick-closing valve is controlled to close using a fixed-value pulse. The valve closing time is a constant Tthreshold4, defined as the pulse closing time threshold 4. When the actual liquid temperature is less than (Temp-YU3), the quick-closing valve is controlled to close using a fixed-value pulse. The valve closing time is a constant Tthreshold5. Since the former temperature is closer to the process requirement, the former requires less steam than the latter, so the valve closing time is relatively longer. Therefore, the constant Tthreshold4 is greater than the constant Tthreshold5.

[0062] The method also includes:

[0063] Obtain production batch information and the standard value of the process temperature maintained in the feed tank corresponding to the production batch information.

[0064] Determine whether the main body of the feeder cylinder and the feed tank are both in a standby, fault-free state. If so, start temperature control of the liquid in the tank until the process temperature standard value is reached; otherwise, return to wait until the production conditions are met.

[0065] The method further includes: with the fast on / off valve closed, slowly opening the steam diaphragm valve to 100%, and then switching the fast on / off valve on and off in a timed manner to ensure that the opening time of the fast on / off valve is a fixed value TON1 and the closing time of the fast on / off valve is a fixed value TFF1. Then, the fast on / off valve is repeatedly opened and closed in a timed manner to eventually form a fixed value pulse wave to control the opening and closing of the fast on / off valve and heat the liquid temperature to the process set value.

[0066] Specifically, the on / off valve is associated with the current tank temperature, and zoned formulaic control is performed based on the tank temperature value to achieve precise temperature control in the form of customized pulses. The pulse activation time is a linear function related to the temperature difference, thus enabling this method to effectively improve the stability and accuracy of material temperature control under specific production conditions.

[0067] The method further includes: maintaining the steam diaphragm valve at 100% opening, opening the quick-on / off valve in a timed manner to ensure that the quick-on / off valve is open for a set time value TON3, and then immediately closing the quick-on / off valve and the steam diaphragm valve to control the upward trend of the liquid temperature in the tank until the liquid temperature in the tank reaches the set maximum value.

[0068] In practical applications, the steam diaphragm valve is kept at 100% opening. The quick-on / off valve is opened in a timed manner, ensuring that the opening time of the quick-on / off valve is exactly TON3. Then, the quick-on / off valve and the steam diaphragm valve are immediately closed. The rising trend of the liquid temperature in the feeder tank is recorded until the liquid temperature in the tank reaches the maximum value Ttmax. The temperature difference TtDiff is calculated. The calculation formula is: TtDiff=Ttmax-(Ttemp-YU1).

[0069] Where TtDiff is the temperature difference, Ttmax is the maximum temperature rise of the liquid in the tank, Ttemp is the process setpoint for the liquid temperature, and YU1 is the threshold.

[0070] According to the formula for the temperature rise of the liquid by absorbing heat: Q=cm(t2-t1), assuming that the specific heat value of each liquid is equal, it can be concluded that the mass m of the liquid is inversely proportional to the temperature difference (t2-t1).

[0071] Therefore, the temperature difference TtDiff in the above formula is related to the theoretical value G of the liquid content in the feeder tank before production.

[0072] Through experimental methods, assuming 140 kg of liquid feed is added to the feeder tank and heated to the value of (Ttemp - YU1), the rapid on / off valve is then opened for a time of TON3 and immediately closed. The temperature difference is recorded as TT, which is experimentally measured.

[0073] Then we have: 140*TT=G*TtDiff;

[0074] After rearranging the terms, we get: TtDiff = 140 * TT / G;

[0075] Since the value of G is a speculative estimate and has a certain deviation, it is only necessary to determine whether TtDiff is within the deviation range based on the above equation to determine whether the theoretical value G of the liquid content in the feeder tank before production is accurate.

[0076] That is, determine whether the value of TtDiff is within the range of the inequality: (140*TT / G)*85%. <TtDiff<(140*TT / G)*115%。

[0077] If the inequality holds true, the predicted G value is accurate. If the inequality does not hold true, an alarm will be triggered indicating that the predicted G value is inaccurate, requiring manual intervention. The G value must be manually entered, and the liquid must be allowed to cool until the temperature drops to near the value of (Ttemp-YU1). The TON3 time-controlled heating test will then be repeated until the inequality is satisfied.

[0078] As can be seen, the present invention provides a method for precise control of the liquid temperature in a tobacco feeding tank. The method uses the remaining steam entering the tank and the actual liquid temperature to adjust the opening of the steam diaphragm valve and the quick-on / off valve on the heating steam pipeline connected to the feeding tank, thereby controlling the liquid temperature in the feeding tank. This solves the problems existing in the temperature control of the liquid in existing tobacco feeding tanks, and can accurately control the heating of the tank by steam, improving the stability and accuracy of the liquid temperature control.

[0079] The structure, features, and effects of the present invention have been described in detail above with reference to the embodiments shown in the figures. The above description is only a preferred embodiment of the present invention, but the present invention is not limited to the scope of implementation shown in the figures. Any changes made in accordance with the concept of the present invention, or equivalent embodiments modified to have equivalent changes, shall be within the protection scope of the present invention as long as they do not exceed the spirit covered by the specification and figures.

Claims

1. A method for precisely controlling the temperature of a tobacco feed tank liquid, characterized in that, The application relates to a feeding tank sealing interlayer connected with a heating steam pipeline, wherein the heating steam pipeline is used for feeding steam into the feeding tank sealing interlayer to heat liquid in the feeding tank; the heating steam pipeline is provided with a steam film valve and a quick on-off valve, so that the heating steam amount delivered by the heating steam pipeline to the feeding tank is controlled through the opening degree values of the steam film valve and the quick on-off valve; whether liquid exists in the feeding tank is judged, and if yes, the residual amount of the liquid in the tank and the actual liquid temperature are obtained; the opening and closing of the steam film valve and the quick on-off valve are controlled according to the residual amount of the liquid in the tank in a zoned formula, and temperature precision control is realized in the form of steam pressure reduction; the opening time TON2 and the closing time TOFF2 of the quick on-off valve are calculated according to the actual value Tt of the liquid temperature, and then the quick on-off valve is repeatedly opened and closed in a timed manner, so that the opening and closing of the quick on-off valve are finally controlled in the form of a fixed value pulse wave, and the liquid temperature in the tank is stabilized to the process setting value Ttemp; the control of the opening and closing of the steam film valve and the quick on-off valve according to the residual amount of the liquid in the tank in a zoned formula comprises the following steps: a first weight threshold value weight1 and a second weight threshold value weight2 are set, the residual amount of the liquid in the tank is judged to be in a corresponding zone, and the opening degree value of the steam film valve is calculated, wherein weight2 < weight1; the corresponding relationship between the opening degree value of the steam film valve and the residual amount of the liquid is constructed, and then the steam pressure is controlled based on the liquid temperature in the tank, so that the temperature control precision is improved; the residual amount of the liquid in the tank is obtained, and the method comprises the following steps: the residual amount Y of the liquid in the tank is calculated according to the formula Y=G-F=B*K+X-F, wherein B is the total weight of the material produced in the previous process, K is a feeding proportion value, X is an experienced value of the residual amount of the liquid material, G is a theoretical value of the residual amount of the liquid in the tank, and F is a total mass flow value accumulated by a feeding flowmeter; the corresponding relationship between the opening degree value of the steam film valve and the residual amount of the liquid is constructed, and the method comprises the following steps: the opening degree value Va of the steam film valve is calculated according to the residual amount Y of the liquid, and the calculation formula is as follows: Va=Y / B; further comprising the following steps: production batch information and a process temperature standard value maintained by the liquid in the feeding tank corresponding to the production batch information are obtained; whether the feeding cylinder body and the feeding tank are in standby fault-free states is judged, and if yes, the liquid temperature control in the tank body is started until the process temperature standard value is reached, otherwise the method returns to waiting until the production conditions are met; further comprising the following steps: in the state that the quick on-off valve is closed, the steam film valve is slowly opened to 100%, then the quick on-off valve is opened and closed in a timed manner, the opening time of the quick on-off valve is a fixed value TON1, the closing time of the quick on-off valve is a fixed value TFF1, then the quick on-off valve is repeatedly opened and closed in a timed manner, and finally a fixed value pulse wave is formed to control the opening and closing of the quick on-off valve, so that the liquid temperature is heated to the process setting value; further comprising the following steps: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 。 2. The method according to claim 1, wherein, ​ ​ ​ 3. The method according to claim 2, wherein, ​ ​ 4. The method according to claim 3, wherein, ​ The steam film valve is kept 100% open, the fast on-off valve is opened in a timed manner, and the time for which the fast on-off valve is kept open is set to a time value TON3, and then the fast on-off valve is closed immediately after the steam film valve, so as to control the rising trend of the temperature of the material liquid in the tank until the temperature of the material liquid in the tank reaches a set maximum value.

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