A method and use for evaluating the permanent deformation of mixed tobacco stems with different stem diameters

Abstract

The present invention discloses a method for evaluating the permanent deformation of mixed tobacco stems with different stem diameters, comprising the following steps: (1) sampling the incoming mixed tobacco stems according to the sample size requirements; (2) dividing the tobacco stem thickness intervals and calculating the weight ratios: according to the divided thickness intervals, measuring the weight ratios of the tobacco stems in each interval; (3) calculating the permanent deformation of the tobacco stems in different thickness intervals; (4) calculating the permanent deformation of the incoming mixed tobacco stems; (5) evaluating the permanent deformation of the mixed tobacco stems. The method of the present invention uses the processing mode of the permanent deformation of the mixed tobacco stems with different stem diameters, making the evaluation of the permanent deformation of the mixed tobacco stems and the evaluation of the pressing effect of different stem diameters more reasonable.

Description

Technical Field

[0001] The present invention belongs to the technical field of tobacco processing, and particularly relates to a method for evaluating the permanent deformation of mixed tobacco stems with different stem diameters; this method can be applied to the quality control of the pressing effect of tobacco stems, especially the process maintenance of the roller gap of a stem press. Background Art

[0002] Tobacco stems are a natural component of tobacco leaves. After being processed into cut stems and blended for use, they play an important role in aspects such as reducing the tar and harmful substances in cigarettes, reducing costs and increasing efficiency, adjusting the smoking taste quality, and combustion state. Now they have become an indispensable component of the cigarette leaf blend formula.

[0003] There are significant differences in the state and density between cut stems and cut tobacco leaves. Poor mixing effect between the two is likely to cause fluctuations in the draw resistance, combustibility, total weight per single cigarette, and cut tobacco density of the rolled cigarettes, thus affecting the cigarette quality. Therefore, cut stems are mostly used in low-grade cigarettes, while they are not used or used in very small amounts in high-grade cigarettes; this cannot fully utilize the raw material advantages of cut stems in reducing raw material consumption and reducing harmful substances and tar. Increasing the proportion of tobacco stems is one of the important measures to enhance the value of cut stems.

[0004] Pressing the tobacco stems is to extrude and form the tobacco stems so that the pressed tobacco stems become sheet-shaped, which is convenient for improving the filamentous form after the tobacco stems are made into filaments and for improving their mixing effect with cut tobacco leaves; therefore, the pressing process of tobacco stems has become one of the key processes for adjusting the filamentous form after the tobacco stems are made into filaments and for adjusting the tissue pore structure. The pressing process of tobacco stems generally adopts hot pressing (tobacco stem temperature ≥ 55°C) or thin pressing process (the roller gap range is generally 0.6 mm - 1.2 mm). Due to the different thicknesses of the incoming tobacco stems (the stem diameter range is 1.0 mm - 10.5 mm), using the same roller gap for treatment will inevitably cause varying degrees of damage to the appearance of thick stems, while there is a phenomenon that thin stems are not fully pressed. The pressing effect of the existing stem presses is mainly evaluated based on the shaping effect of thick stems (stem diameter > 2.38 mm), that is, the thinner the thick stems are in sheet form and there are no large-area damage and breakage on the appearance, it is considered that the roller gap setting of the stem press under this condition is reasonable. However, under this condition, due to the thin stems not being fully pressed, the cross-section of the thin stems still shows a crescent-shaped distribution, and this part of the pressing does not achieve the technical purpose of the thin pressing process. From the filamentous appearance of the cut stems after being made into filaments, before entering the cutting process, due to the semi-circular or crescent-shaped morphological distribution characteristics of the thin stems, it is extremely easy to have quality defects such as the cut stems becoming round sheet-shaped instead of filamentous after cutting; this causes phenomena such as running stems and leaking stems prone to occur during the operation of the subsequent cut stem machine. Therefore, adjusting a reasonable roller process to make the permanent deformation of the mixed tobacco stems with different stem diameters meet the target requirements is the goal pursued by the pressing process of tobacco stems; however, there is currently no established judgment standard and judgment method for the permanent deformation of the mixed tobacco stems with different stem diameters.

[0005] The present invention is proposed to solve the above problems. Summary of the Invention

[0006] The present invention provides a method for evaluating the permanent deformation of mixed tobacco stems with different stem diameters. Calculating the permanent deformation of the mixed tobacco stems by the method of the present invention has a clear physical meaning. The method of the present invention changes the traditional stem-making wire processing mode that takes the thick stems in the tobacco stem formula as the guiding effect of pressing the stems, and transforms it into a processing mode based on the permanent deformation of the mixed tobacco stems with different stem diameters, effectively avoiding the phenomenon that the fine stems are not sufficiently compressed, resulting in a large number of flaky stem wires and broken stem wires after the fine stems are made into wires. The method of the present invention provides a direction for adjusting the pressing gap of the stem press when the proportion of tobacco stems with different stem diameters in the same tobacco stem feedstock changes, thereby improving the filamentous appearance effect of the stem wires after wire making.

[0007] The technical solution of the present invention is as follows:

[0008] The first aspect of the present invention discloses a method for evaluating the permanent deformation of mixed tobacco stems with different stem diameters, including the following steps:

[0009] (1) Sampling the incoming mixed tobacco stems according to the sample size requirements;

[0010] (2) Dividing the tobacco stem thickness interval and the weight ratio: According to the thickness interval division, measuring the weight ratio of the tobacco stems in each interval;

[0011] (3) Calculating the permanent deformation of the tobacco stems in different thickness intervals;

[0012] (4) Calculating the permanent deformation of the incoming mixed tobacco stems;

[0013] (5) Evaluating the permanent deformation of the mixed tobacco stems.

[0014] Preferably, in step (1), the incoming mixed tobacco stems are sampled by the quartering method, and the test sample size is 1000 g ± 50 g.

[0015] Preferably, in step (2), a tobacco stem multi-layer vibrating sieve is used for classifying and measuring the thickness of the tobacco stems; the test method standard is the method part in Sections 4.3 and 5.2 of GB / T 21136-2007 "Determination of the Stem Content in Cut Tobacco Leaves"; the thickness interval is divided into three intervals, namely: the fine tobacco stem interval, with a thickness range of d1 ≤ 1.70 mm; the medium tobacco stem interval, with a thickness range of 1.70 mm < d2 ≤ 2.38 mm; the thick tobacco stem interval, with a thickness range of d3 > 2.38 mm.

[0016] Preferably, in step (3), the calculation method for the permanent deformation of the tobacco stems in different thickness intervals is as follows:

[0017] Permanent deformation of fine tobacco stems ε cs1 Calculated according to the following formula: ε cs1 = 0.3679 - 0.1797 * h set ;

[0018] Permanent deformation ε of medium tobacco stems cs2 Calculated according to the following formula: ε cs2 = 0.6840 - 0.3404 * h set ;

[0019] Permanent deformation ε of thick tobacco stems cs3 Calculated according to the following formula: ε cs3 = 0.7747 - 0.3868 * h set ;

[0020] Wherein, h set is the nip gap set by the stem rolling machine.

[0021] Preferably, the permanent deformation ε of the incoming mixed tobacco stems in step (4) csm Calculated according to the following formula: ε csm = ε cs1 × η1 + ε cs2 × η2 + ε cs3 × η3; wherein, η1 is the percentage of the weight of fine tobacco stems; η2 is the percentage of the weight of medium tobacco stems; η3 is the percentage of the weight of thick tobacco stems.

[0022] Preferably, the evaluation of the permanent deformation of the mixed tobacco stems is that the closer the permanent deformation ε of the mixed tobacco stems csm is to the standard permanent deformation ε b , the more qualified the permanent deformation ε of the mixed tobacco stems csm is.

[0023] Preferably, the value of the standard permanent deformation ε of the mixed tobacco stems b is 0.440 ± 0.005. At this time, after the tobacco stems are made into cut stems, the cut stem shape is closest to the filamentous cut stems, and at the same time, the whole cut stem rate and long cut stem rate are the highest.

[0024] The second aspect of the present invention discloses the use of the described method for setting the nip gap of a stem rolling machine.

[0025] Preferably, according to the difference degree between the permanent deformation ε csm and the standard permanent deformation ε b , determine the corresponding tobacco stem gap maintenance method. Generally, the trial and error method is used to determine the most suitable nip gap: if the mixed permanent deformation ε csm is less than the standard permanent deformation ε b , then the nip gap is appropriately reduced. Taking 0.01 mm as the nip gap adjustment step, repeat the above steps (3) to (5), and use the trial and error method to maintain the tobacco stem gap so that the mixed permanent deformation ε csm reaches 0.440 ± 0.005;

[0026] If the mixed permanent deformation ε csmGreater than the standard permanent deformation ε b , the press roller gap is appropriately increased, and the maintenance steps are the same as above. If the mixed permanent deformation ε csm is greater than the standard permanent deformation ε b , the filamentous effect after the tobacco stems are made into filaments is better, but the long filament rate of the stem filament structure decreases significantly, and the stem filament yield decreases significantly. To control the cost of stem filaments and formulations, it is also necessary to maintain the press roller gap in a targeted manner so that the mixed permanent deformation ε csm reaches 0.440 ± 0.005.

[0027] Advantages of the present invention:

[0028] 1. The present invention provides a method for evaluating the mixed permanent deformation of tobacco stems with different stem diameters. The method of the present invention changes the traditional processing mode of making stem filaments with the thick stems in the tobacco stem formula as the guide for the press roller effect, and changes it to a processing mode based on the mixed permanent deformation of tobacco stems with different stem diameters, making the evaluation of the permanent deformation of mixed tobacco stems and the evaluation of the press roller effect of different stem diameters more reasonable.

[0029] 2. The method of the present invention is used for setting the press roller gap of the press roller machine, and has significant advantages in improving the filamentous quality of the stem filaments. When using the method of the present invention to set the press roller gap of the press roller machine, due to fully considering the permanent deformation of the press roller of the medium stems and the fine stems, the press roller effect of the fine stems and the medium stems is significantly improved, effectively reducing the proportion of flaky stem filaments in the finished stem filaments and significantly improving the filamentous appearance effect of the stem filaments; at the same time, it can significantly reduce the phenomenon of running stems and leaking stems during the subsequent cutting of stem filaments and improve the operating conditions of the stem filament cutting machine.

[0030] 3. The method of the present invention is used for setting the press roller gap of the press roller machine, providing a direction for adjusting the press roller gap when the proportion of tobacco stems with different stem diameters changes for the same incoming material of tobacco stems. Specific embodiments

[0031] In order to make the purpose, technical solution and beneficial effects of the present invention clearer, the following will be described in detail in combination with embodiments for the convenience of those skilled in the art to understand.

[0032] Example 1: Evaluation of the permanent deformation of the mixed tobacco stem A after pressing for a certain brand of incoming material

[0033] In the press roller section, the moisture content of the tobacco stem A before pressing is 33.5%, the process flow rate is 3000 kg / h, and the press roller gap is set at 0.8 mm.

[0034] The steps are as follows:

[0035] (1) Sampling for tobacco stem detection, sampling the incoming mixed tobacco stems by the quartering method, and the test sample amount is 1000 g ± 50 g.

[0036] (2) Use a multi-layer vibrating sieve for tobacco stems to measure the classification of stem pressing. The test method standard is the method part in Sections 4.3 and 5.2 of GB / T 21136-2007 "Determination of Stem Content in Threshed Tobacco Leaves". According to the distribution results of the measured tobacco stem thickness intervals, the tobacco stem thickness intervals are divided into three intervals, and the weight proportion of tobacco stems in each thickness interval is marked as η1, η2, and η3. The measurement results are shown in Table 1 below:

[0037] Table 1 Detection of Tobacco Stem Thickness Intervals and Weight Proportions

[0038]

[0039] (3) Calculate the permanent deformation of tobacco stems in different thickness intervals; under the condition that the nip gap hset of the stem press is set to 0.8 mm, according to the data in Table 1, calculate the permanent deformation of tobacco stems corresponding to different thickness intervals respectively, where:

[0040] Permanent deformation ε of thin tobacco stems cs1 Calculate according to the following formula: ε cs1 = 0.3679 - 0.1797 * h set ;

[0041] Permanent deformation ε of medium tobacco stems cs2 Calculate according to the following formula: ε cs2 = 0.6840 - 0.3404 * h set ;

[0042] Permanent deformation ε of thick tobacco stems cs3 Calculate according to the following formula: ε cs3 = 0.7747 - 0.3868 * h set ;

[0043] The calculation results are shown in Table 2:

[0044] Table 2 Permanent Deformation of Tobacco Stems in Different Interval Thicknesses

[0045]

[0046] (4) Calculate the permanent deformation of the incoming mixed tobacco stems: Substitute the permanent deformation and weight proportion of tobacco stem samples in different thickness intervals into the following formula to calculate the permanent deformation ε of the mixed tobacco stems csm .

[0047] ε csm = ε cs1 × η1 + ε cs2 × η2 + ε cs3 × η3 (3)

[0048] Among them, η1 is the percentage of the weight of fine tobacco stems; η2 is the percentage of the weight of medium tobacco stems; η3 is the percentage of the weight of thick tobacco stems. The results are shown in Table 3, and ε csm is 0.439.

[0049] Table 3 Permanent deformation of the incoming mixed tobacco stems

[0050]

[0051] (5) Evaluate the permanent deformation of the mixed tobacco stems; the standard permanent deformation ε b value of the mixed tobacco stems is 0.440. The ε csm in this embodiment is 0.439, which is close to the standard permanent deformation ε b value of 0.440. This shows that the permanent deformation of the mixed tobacco stems in this embodiment is good, and further shows that the setting of the roller gap of the tobacco stem press is reasonable.

[0052] Example 2: Evaluation of the permanent deformation of the mixed tobacco stems of a certain brand of incoming tobacco stems B after pressing.

[0053] In the tobacco stem pressing section, the moisture content of the incoming tobacco stems B before pressing is 33.5%, and the process flow rate is 1500 kg / h; the roller gap is set to 0.8 mm;

[0054] The steps are as follows:

[0055] (1) Take samples of the tobacco stems for detection. Take samples of the incoming mixed tobacco stems by the quartering method, and the test sample quantity is 1000 g ± 50 g.

[0056] (2) Use a multi-layer vibrating sieve for tobacco stems to measure the classification of the pressed tobacco stems. The test method standard is the method part in Sections 4.3 and 5.2 of GB / T 21136-2007 "Determination of the Stem Content in Threshed Tobacco Leaves". Divide the tobacco stem thickness range and the weight percentage. According to the measured tobacco stem thickness range distribution results, divide it into three thickness ranges, and mark the weight percentage of the tobacco stems in each thickness range as η1, η2, and η3. The measurement results are shown in Table 4 below:

[0057] Table 4 Detection of tobacco stem thickness and weight percentage

[0058]

[0059] (3) Calculate the permanent deformation of the tobacco stems in different thickness ranges; under the condition that the roller gap h set set in the tobacco stem press is 0.8 mm, according to the data in Table 4, calculate the permanent deformation of the tobacco stems corresponding to different thickness ranges respectively, where:

[0060] The permanent deformation ε cs1 of the fine tobacco stems is calculated according to the following formula: ε cs1 = 0.3679 - 0.1797 * hset ;

[0061] The permanent deformation ε of medium tobacco stems cs2 is calculated according to the following formula: ε cs2 = 0.6840 - 0.3404 * h set ;

[0062] The permanent deformation ε of thick tobacco stems cs3 is calculated according to the following formula: ε cs3 = 0.7747 - 0.3868 * h set ;

[0063] The calculation results are shown in Table 5:

[0064] Table 5 Permanent deformation of tobacco stems with different interval thicknesses

[0065]

[0066] (4) Calculate the permanent deformation of the incoming mixed tobacco stems: Substitute the permanent deformation and weight ratio of the tobacco stem samples in different thickness intervals into the following formula to calculate the permanent deformation ε of the mixed tobacco stems csm .

[0067] ε csm = ε cs1 × η1 + ε cs2 × η2 + ε cs3 × η3 (3)

[0068] where η1 is the weight ratio % of fine tobacco stems; η2 is the weight ratio % of medium tobacco stems; η3 is the weight ratio % of thick tobacco stems. The results are shown in Table 6, and ε csm is 0.423.

[0069] Table 6 Permanent deformation of the incoming mixed tobacco stems

[0070]

[0071] (5) Evaluate the permanent deformation of the mixed tobacco stems; the standard permanent deformation ε b value of the mixed tobacco stems is 0.440. The ε csm in this embodiment is 0.423, which has a large difference from the standard permanent deformation ε b value of 0.440. This shows that the permanent deformation of the mixed tobacco stems in this embodiment is poor, indicating that the setting of the roller gap of the stem press does not match the incoming tobacco stems, and the roller gap of the stem press needs to be readjusted.

[0072] Use the trial-and-error method to determine the most suitable stem pressing gap: The permanent deformation of the mixture ε csmSince 0.423 is less than the standard permanent deformation of 0.440, the gap of the rolling and pressing roller needs to be appropriately reduced. Taking 0.01 mm as the adjustment step of the gap of the rolling and pressing roller, repeat the above steps (3) to (5), and use the trial and error method to maintain the gap of the tobacco stems. After the gap of the rolling and pressing roller of the rolling and pressing machine in this embodiment is readjusted to 0.75 mm, ε csm is 0.440, exactly equal to the value 0.440 of the standard permanent deformation ε b ; at this time, the gap of the rolling and pressing roller of the rolling and pressing machine is reasonably set.

[0073] Example 3 Evaluation of the mixed permanent deformation of the tobacco stems C of a certain brand after rolling and pressing.

[0074] In the rolling and pressing section, the moisture content of the tobacco stems C before rolling and pressing is 33.5%, and the process flow rate is 1500 kg / h; the gap of the rolling and pressing roller is set to 0.8 mm;

[0075] The steps are as follows:

[0076] (1) Sampling for tobacco stem detection, sampling the incoming mixed tobacco stems by the quartering method, and the test sample quantity is 1000 g ± 50 g.

[0077] (2) Measuring the classification of the rolled and pressed tobacco stems with a multi-layer vibrating sieve for tobacco stems. The test method standard is the method part in Sections 4.3 and 5.2 of GB / T 21136-2007 Determination of the Stem Content in Threshed Tobacco Leaves. According to the measurement results of the distribution of the tobacco stem thickness intervals, the tobacco stems are divided into three thickness intervals, and the weight proportion of the tobacco stems in each thickness interval is marked as η1, η2, and η3. The measurement results are shown in Table 7 below:

[0078] Table 7 Detection of Tobacco Stem Thickness and Weight Proportion

[0079]

[0080] (3) Calculate the permanent deformation of the tobacco stems in different thickness intervals; under the condition that the gap h set of the rolling and pressing roller set by the rolling and pressing machine is 0.8 mm, according to the data in Table 7, calculate the permanent deformation of the tobacco stems corresponding to different thickness intervals respectively, where:

[0081] The permanent deformation ε cs1 of the thin tobacco stems is calculated according to the following formula: ε cs1 = 0.3679 - 0.1797 * h set ;

[0082] The permanent deformation ε cs2 of the medium tobacco stems is calculated according to the following formula: ε cs2 = 0.6840 - 0.3404 * h set ;

[0083] The permanent deformation ε of the thick tobacco stemscs3 Calculate according to the following formula: ε cs3 = 0.7747 - 0.3868 * h set ;

[0084] The calculation results are shown in Table 8:

[0085] Table 8 Permanent deformation of tobacco stems with different interval thicknesses

[0086]

[0087] (4) Calculate the permanent deformation of the incoming mixed tobacco stems: Substitute the tobacco stem samples with different thickness intervals and their permanent deformations and weight ratios into the following formula to calculate the permanent deformation ε of the mixed tobacco stems csm .

[0088] ε csm = ε cs1 × η1 + ε cs2 × η2 + ε cs3 × η3 (3)

[0089] where η1 is the weight ratio percentage of thin tobacco stems; η2 is the weight ratio percentage of medium tobacco stems; η3 is the weight ratio percentage of thick tobacco stems. The results are shown in Table 9, and ε csm is 0.459.

[0090] Table 9 Permanent deformation of the incoming mixed tobacco stems

[0091]

[0092] (5) Evaluate the permanent deformation of the mixed tobacco stems; the standard permanent deformation ε b value is 0.440. The ε csm in this embodiment is 0.459, which is quite different from the standard permanent deformation ε b value of 0.440. This shows that the permanent deformation of the mixed tobacco stems in this embodiment is poor, indicating that the setting of the pressure roller gap of the press roller is not matched with the incoming tobacco stems, and the pressure roller gap of the press roller needs to be readjusted.

[0093] Use the trial and error method to determine the most suitable pressure roller gap: Since the mixed permanent deformation ε csm is 0.459, which is greater than the standard permanent deformation of 0.440, the pressure roller gap of the press roller needs to be appropriately increased. Taking 0.01 mm as the adjustment step of the pressure roller gap, repeat the above steps (3) to (5), and use the trial and error method to maintain the tobacco stem gap. After the pressure roller gap of the press roller in this embodiment is readjusted to 0.85 mm, ε csm is 0.440. At this time, the setting of the pressure roller gap of the press roller is reasonable.

[0094] The foregoing has shown and described the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification are only used to illustrate the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements fall within the scope of the present invention claimed. The scope of the present invention claimed is defined by the appended claims and their equivalents.

Claims

1. A method for evaluating the permanent deformation of mixed tobacco stems with different stem diameters, characterized in that, It includes the following steps: (1) Sampling the incoming mixed tobacco stems according to the sample size requirement; (2) Division of tobacco stem thickness intervals and weight ratios: According to the division of thickness intervals, measure the weight ratio of tobacco stems in each interval; Use a multi-layer vibrating sieve for tobacco stems to measure the thickness classification; The test method shall comply with the requirements of GB / T 21136-2007; The thickness intervals are divided into three intervals, namely: the fine tobacco stem interval, with a thickness range of d1≤1.70mm; the medium tobacco stem interval, with a thickness range of 1.70 mm<d2≤2.38mm; the thick tobacco stem interval, with a thickness range of d3>2.38mm; (3) Calculate the permanent deformation of tobacco stems in different thickness intervals; The calculation method is: Permanent deformation of fine tobacco stems Calculated according to the following formula: ; Permanent deformation of tobacco stems Calculate according to the following formula: ; Permanent deformation of thick tobacco stems Calculated according to the following formula: ; where h set is the nip gap set for the stem rolling machine; (4) Calculate the permanent deformation of the incoming mixed tobacco stems; (5) Evaluate the permanent deformation of the mixed tobacco stems; Step (4) Permanent deformation of the incoming mixed tobacco stems Calculate according to the following formula: ; where is the percentage by weight of fine tobacco stems%; is the percentage by weight of medium tobacco stems%; is the percentage by weight of thick tobacco stems%.

2. The method according to claim 1, wherein In step (1), sample the incoming mixed tobacco stems by the quartering method, and the sample size is 1000g±50g.

3. The method according to claim 1, characterized in that The evaluation of the permanent deformation of the blended tobacco stems is the permanent deformation of the blended tobacco stems The closer it is to the standard permanent deformation , the permanent deformation of the blended tobacco stems is more qualified.

4. The method according to claim 3, characterized in that, Standard permanent deformation of the blended tobacco stems The value is 0.440 ± 0.

005.

5. The method according to any one of claims 1-4, characterized in that, For the purpose of setting the nip of the rolling machine.

6. The method according to claim 5, wherein If the mixed permanent deformation is less than the standard permanent deformation , the gap of the rolling stem is appropriately reduced to make the mixed permanent deformation reach 0.440±0.005; if the mixed permanent deformation is greater than the standard permanent deformation , the gap of the rolling stem is appropriately increased to make the mixed permanent deformation reach 0.440±0.005.

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