JP2014020728A - Method for driving rotary kiln - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the maximum rotational power required in total for driving a plurality of rotary kilns each having a lifter inside thereof.SOLUTION: A method for driving a plurality of rotary kilns 110a, 110b having respective lifters 112a, 112b inside thereof, comprises: providing driving means 130 shared by the rotary kilns 110a, 110b; and arranging the rotary kilns 110a, 110b so that positional distribution of a raw material in one of the rotary kilns 110 varies in a phase different from that of the other of the rotary kilns 110.

Description

  The present invention relates to a method for driving a rotary kiln.

  The rotary kiln is an inclined rotating cylindrical furnace, and is an apparatus that performs various processes while moving the charged raw material in the axial direction by rolling. For example, a wide range of raw materials such as ore, food, waste, and livestock excrement are used in many processes such as mixing, heating, drying, baking, cooling, and granulation. When heating is required, an internal heating method in which the raw material and the high-temperature gas are directly contacted in the kiln, an external heating method in which the raw material is indirectly heated through the kiln cylinder, or the like is used.

  In such rotary kilns, in order to promote homogenization by mixing raw materials, or to promote the heating efficiently by promoting contact between the kiln cylinder and the raw materials, in particular, an external heating method is also known. Yes. The lifter is a member that lifts (scraps) the raw material in the furnace as the name suggests. As an example of the lifter, Patent Document 1 describes a partition wall that divides the inside of the kiln into a plurality of sections and a ridge extending in the longitudinal direction of the kiln. Patent Document 2 describes a partition wall that divides the inside of the kiln into a central portion and an outer peripheral portion, and further divides the outer peripheral portion radially.

JP 52-57228 A JP 2005-351495 A

  Here, the rotary kiln rotates by receiving rotational power from driving means such as a motor. The rotational power from the drive means is transmitted to a roller (or gear) provided around the outer wall surface of the kiln through a speed reducer. The rotational power of the rotary kiln can be broadly divided into a force that opposes the frictional force generated by the dead weight of the kiln (hereinafter also referred to as frictional power) and a force that is required to scrape the raw material in the kiln (hereinafter referred to as scraping). It is also called as raising power).

  FIG. 10 is a diagram for explaining the rotational power of the rotary kiln. The rotary kiln facility 10 includes a kiln 11 and a support roller 12. The kiln 11 is installed on the support roller 12. The support roller 12 is rotated by rotational power P transmitted from a driving unit (not shown), and the kiln 11 is rotated as the support roller 12 rotates.

The rotational power P is the sum of the friction power P1 and the scraping power P2, and is represented by the following formula 1.
P = P1 + P2 (Formula 1)

First, the frictional power P1 will be described. The frictional power P1 is a force that opposes friction in a bearing of a power transmission member such as the support roller 12 interposed between the driving unit and the kiln. The frictional power P1 is proportional to the mass of the kiln 11 containing the raw material, and is expressed as a function as in the following Expression 2. P1 is the friction power (kW), W is the mass (kg) of the kiln 11 containing the raw material, R is the radius (m) of the kiln 11, r1 is the radius (m) of the support roller 12, and r2 is the radius of the support roller 12. The shaft radius (m), μ is the bearing portion friction coefficient of the support roller, and n is the rotational speed (rpm) of the kiln 11.
P1 = f ₁ (W, R, r1, r2, μ, n) (Expression 2)

Next, the scraping power P2 will be described. The scraping power P2 is based on the scraping torque and the kiln rotational speed that are required when the raw material is scraped up by the frictional force between the kiln 11 and the inner wall. That is, the scraping power P2 is proportional to the mass of the raw material inside the kiln 11, the scraping torque obtained from the distance from the kiln center, and the rotational speed of the kiln 11. In the figure, w ′ is the mass (kg) of the minute portion of the raw material, and X is the horizontal distance (m) from the kiln center to the minute portion. The scraping torque is obtained by accumulating the scraping torque necessary for this minute portion over the entire raw material. Accordingly, the scraping power Ps (kW) is expressed as a function as in the following Expression 3.
P2 = f ₂ (Σ (w ′ × X), n) (Formula 3)

Here, in Equation 2 above, each parameter of the function f ₁ does not change depending on the rotational state of the kiln 11 as long as the rotational speed n is constant. That is, the frictional power P1 is substantially constant regardless of the rotation state of the kiln 11. Further, when no lifter is provided in the kiln 11 as in the illustrated example, the deposition surface of the raw material scraped up by the frictional force between the kiln 11 and the inner wall is substantially constant according to the angle of repose. Maintained. Therefore, the position of the raw material is kept almost constant. Therefore, the scraping power P2 in Expression 3 is also substantially constant regardless of the rotation state of the kiln 11 if the rotation speed n is constant. Therefore, in the illustrated example, the rotational power P is substantially constant regardless of the rotation state of the kiln 11 if the rotational speed n is constant.

In such a case, for example, when a plurality of kilns 11 are installed in the rotary kiln facility 10 in order to increase the throughput of raw materials, the rotational power P _TTL required as a whole is a simple sum of the rotational powers P of the individual kilns 11. . Therefore, even if a drive unit is provided for each kiln 11 or a drive unit is shared by a plurality of kilns 11, the required rotational power P _TTL is almost the same as a whole.

  However, as described above, in a rotary kiln, a lifter can be provided inside the kiln. In this case, the raw material is scraped up to a higher position by the lifter and falls. That is, depending on the position of the lifter that changes as the kiln 11 rotates, the stage where the raw material is scraped up and the stage where it falls are repeated. Therefore, the position distribution of the raw material in the furnace changes as the kiln 11 rotates. This means that in Equation 3 above, the torque Σ (w ′ × X) required for scraping the raw material changes, and therefore the scraping power P2 also varies depending on the rotation state of the kiln 11. is there.

  When the present inventors diligently researched about the rotational power P, it was found that the scraping power P2 occupies a large proportion of the rotational power P. The scraping power P2 often occupies 50% or more of the rotational power P. For example, if the raw material is a heavy material such as ore, it may exceed 80%. As described above, when the lifter is provided inside the kiln 11, the scraping power P <b> 2 becomes a fluctuation component that depends on the rotation state of the kiln 11. Accordingly, the fact that the scraping power P2 occupies a large proportion of the rotational power P means that when the lifter is provided inside the kiln 11, most of the rotational power P becomes a fluctuation component.

Therefore, the present inventors provide a plurality of kilns having lifters in the rotary kiln equipment, share the driving means among them, and appropriately combine the rotation states of the kilns as a whole. It was conceived that the scraping power P2 _TTL was reduced, and as a result, the overall rotational power P _TTL was reduced. This invention is made | formed in view of this knowledge, The place made into the objective of this invention reduces the maximum value of the rotational power required as a whole when driving the some rotary kiln which has a lifter inside. It is an object of the present invention to provide a new and improved method of driving a rotary kiln.

  In order to solve the above-described problem, according to one aspect of the present invention, there is provided a driving method for a plurality of rotary kilns having lifters therein, and driving means common to the plurality of rotary kilns is provided, and the raw material in each rotary kiln is provided. A method for driving a rotary kiln is provided, wherein a plurality of rotary kilns are arranged so that the position distribution changes at different phases.

  In a rotary kiln having a lifter inside, the position distribution of the raw material inside changes periodically. Therefore, the power required to scoop up the raw material also changes periodically. Therefore, if a plurality of kilns are arranged so that the phase of the periodic change in the position distribution of the raw material is different between the kilns, and these kilns are connected to a common driving means, the scraping power between the kilns is increased. As a result, the maximum rotational power required as a whole becomes smaller than the sum of the maximum rotational power required for each kiln.

  The rotary kiln driving method described above may drive two rotary kilns. When two rotary kilns are driven, the effect of reducing the maximum value of the rotational power required as a whole is particularly remarkable due to the timing at which the scraping power is maximized between the kilns. Of course, three or more rotary kilns may be driven.

  In the above rotary kiln driving method, the plurality of rotary kilns may be arranged such that the positions of the lifters with respect to the rotary kilns are different from each other. Since the position distribution of the raw material in the furnace changes according to the position of the lifter, if each kiln is arranged so that the position of the lifter (relative position with respect to the kiln body) is different from each other, the position distribution of the raw material is different from each other. It can be changed in phase. The shape of the lifter here is not particularly limited. The shape of the lifter may be, for example, a partition wall, a ridge, or another shape.

  Further, in the above rotary kiln driving method, the lifter is a partition wall that divides the inside of the rotary kiln into a plurality of compartments, and the plurality of rotary kilns are arranged so that the positions of the compartments into which raw materials are charged are different from each other. May be arranged. When the lifter is a partition wall, it is possible to set a compartment in which the raw material is charged and a compartment that is not so in the kiln. If the respective kilns are arranged so that the positions of the sections into which the raw materials are charged (relative positions with respect to the kiln main body) are different from each other, the position distribution of the raw materials can be changed in different phases. In this case, the position of the lifter may be the same in each kiln or may be different.

  In the above rotary kiln driving method, the phase difference of the raw material position distribution among the plurality of rotary kilns (the angular difference in the rotational direction of the positional distribution change between the kilns) is the period of the raw material position distribution (at each kiln). It may be equal to a value obtained by dividing the rotation angle until the material has the same position distribution again by the number of rotary kilns. In other words, phase distributions of substantially equal intervals are added to the position distribution of raw materials in a plurality of kilns.

  For example, when the inside of the kiln is divided into two by the partition wall, the change in the raw material position distribution is repeated each time the kiln rotates 180 °. That is, the period of the position distribution of the raw material is 180 °. In this case, when two kilns are arranged, a phase difference of 90 ° (= 180 ° / 2) is given. Similarly, if three kilns are arranged, a phase difference of 60 ° (= 180 ° / 3) can be obtained. Further, when the inside of the kiln is divided into four by the partition wall, the change in the raw material position distribution is repeated each time the kiln rotates 90 °. That is, the period of the position distribution of the raw material is 90 °. In this case, if two kilns are arranged, a phase difference of 45 ° (= 90 ° / 2) can be obtained. By setting it as this structure, the sum total of scraping power can be leveled more.

  In the rotary kiln driving method described above, at least a part of the plurality of rotary kilns may rotate by being transmitted with power from the driving means via other rotary kilns. When the driving means is shared by a plurality of kilns, it is possible to freely set how the rotational power is transmitted from the driving means to each kiln according to various conditions.

  As described above, according to the present invention, when driving a plurality of rotary kilns having lifters inside, the maximum value of rotational power required as a whole can be reduced.

  Accordingly, for example, the maximum output of the driving means per one rotary kiln can be smaller, so that the equipment cost is reduced. Further, since the fluctuation range of the load becomes small, the fatigue and wear of the driving means are reduced, and maintenance may be facilitated.

It is a figure for demonstrating calculation of the scraping torque in a rotary kiln. It is a figure showing the schematic structure of the rotary kiln equipment concerning a 1st embodiment of the present invention. It is a graph which shows the change of the scraping torque in the rotary kiln installation shown in FIG. It is a figure which shows schematic structure of the rotary kiln installation which concerns on the 2nd Embodiment of this invention. It is a graph which shows the change of the scraping torque in the rotary kiln installation shown in FIG. It is a figure which shows schematic structure of the rotary kiln installation which concerns on the 3rd Embodiment of this invention. It is a graph which shows the change of the scraping torque in the rotary kiln installation shown in FIG. It is a figure which shows schematic structure of the rotary kiln installation which concerns on the 4th Embodiment of this invention. It is a figure which shows schematic structure of the rotary kiln installation which concerns on the 5th Embodiment of this invention. It is a figure for demonstrating the rotational power of a rotary kiln.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In the present specification and drawings, components having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

(Calculation of scraping torque)
First, with reference to FIG. 1, calculation of the scraping torque that is the basis of the present invention will be described. In the following description, as an example, the scraping torque is calculated for a rotary kiln that is not provided with a lifter. However, the scraping torque can be similarly calculated for a rotary kiln that is provided with a lifter.

  In the following calculation, the X axis is set in the horizontal direction and the Y axis is set in the vertical direction with the center of the kiln 11 as the origin. Then, the torque required for scraping is calculated for each of the microelements E obtained by dividing the raw material in the kiln 11 in the horizontal direction for each width ΔX. The sum of the torques calculated for each element E is the torque required to scoop up the raw material inside the kiln 11 (hereinafter also referred to as scooping torque).

In FIG. 1, points A and B are the lower end and the upper end of the raw material deposition surface. Here, when the deposition surface of the raw material is substantially flat, a straight line AB (Y = aX + b; a and b are constants) representing a cross section of the deposition surface can be defined. When the coordinates of the point A are (X ₁ , Y ₁ ) and the coordinates of the point B are (X ₂ , Y ₂ ), both the points A and B are intersections of the straight line AB and the inner wall of the kiln 11. Therefore, the relationship between X ₁ and Y ₁ , and X ₂ and Y ₂ is expressed by the following equations 4 and 5 using the radius R of the kiln 11 and the constants a and b.

  For each microelement E, if the upper end coordinates are (X, Y) and the lower end coordinates are (X, Y ′), the width of the microelement E is the division width ΔX and the height is ΔY = Y−Y ′. . Here, since the upper end of the microelement E is on the straight line AB and the lower end of the microelement E is on the inner wall of the kiln 11, Y and Y 'are expressed by the following Expression 6.

  Therefore, the area S of the microelement E is expressed by the following Expression 7.

The cross-sectional area S _{TTL of the} raw material inside the kiln 11 is equal to the integration of the area S of the microelement E represented by the above equation 6 from X = X ₂ to X = X ₁ , according to the following equation 8: Desired.

  Here, as conditions for calculation, as shown in Table 1 below, specifications of the kiln and the raw material are given.

Sectional area _{S TTL} of the raw materials is determined by Equation 8 described above, to be equal to the cross-sectional area _{S M} of the raw materials shown in Table 1, Formula 4, Formula 5, X1 using Equation 8, Y1, X2, Y2 , B, the convergence calculation is performed, and the result is as shown in Table 2 below. Note that a is equal to -tan (α) and is -0.7.

  By substituting the above result into Equation 6 above and setting an appropriate ΔX, the area S of the microelement E can be obtained. If the bulk specific gravity γ and the kiln effective length L of the raw material are applied to the area S, the mass w ′ of the raw material corresponding to the microelement E can be obtained. If the distance to the center of the kiln 11, that is, the origin, is given to the mass w ′, the torque required to scoop up the raw material corresponding to the microelement E is obtained. When ΔX is a value obtained by dividing the raw material into 1000 equal parts in the X-axis direction, that is, ΔX = (X1−X2) / 1000 = about 0.0012 (m), the total torque is about 14.4 (kN -M).

  In addition, since the scraping torque in each embodiment of the present invention described below is calculated by the same calculation as in the above example, a detailed description of the calculation is omitted. As will be apparent to those skilled in the art, even when a lifter is provided in the furnace, only the function that defines the region of the raw material is changed, so the scraping torque is calculated in the same manner as in the above example. Is possible.

(First embodiment)
Subsequently, a first embodiment of the present invention will be described with reference to FIGS.

  FIG. 2 is a diagram showing a schematic configuration of the rotary kiln facility according to the first embodiment of the present invention. The rotary kiln facility 100 has two kilns 110a and 110b. Each of the kilns 110a and 110b is provided with partition walls 112a and 112b that divide the interior into two sections as lifters. The raw materials in the kilns 110a and 110b are scraped up by the partition walls 112a and 112b, respectively. Therefore, as shown in the figure, the position distribution of the raw materials in the kilns 110a and 110b differs depending on the positions of the partition walls 112a and 112b.

  Here, as shown in the figure, the kilns 110a and 110b are arranged on the support roller 120 so that the positions of the partition walls 112a and 112b have a phase difference of 90 °. That is, for example, when the partition wall 112a is horizontal, the partition wall 112b is vertical. Conversely, when the partition wall 112a is vertical, the partition wall 112b is horizontal. As a result, the position distribution of the raw materials inside the kilns 110a and 110b changes at different phases.

  On the other hand, the support roller 120 is connected to the motor 130 via the speed reducer 140. The rotational power from the motor 130 is transmitted to the support roller 120 via the speed reducer 140, and the kilns 110a and 110b rotate at the same rotational speed as the support roller 120 rotates. In the present embodiment, the kilns 110a and 110b are thus connected to the motor 130 which is a common driving means, and the phase difference of the position distribution of the raw materials inside the kilns 110a and 110b is maintained.

  FIG. 3 is a graph showing changes in the scraping torque in the rotary kiln facility shown in FIG. In FIG. 3, the kiln 110 a is denoted as kiln A, and the kiln 110 b is denoted as kiln B. In this example, with the positions of the partition walls 112a and 112b maintaining a phase difference of 90 °, the kiln A and the kiln B are sequentially rotated at intervals of 10 ° to 15 °, respectively, and the scraping torque is calculated. In addition, the specifications of the kiln and the raw material (common to kiln A and kiln B) that are the calculation conditions are as shown in Table 3 below. In addition, the amount of raw materials which exist in two divisions formed with a partition wall shall be equal.

  Referring to the graph, it can be seen that both the kiln A and the kiln B change the scraping torque with a period of 180 ° (kiln rotation angle). This is because the position distribution of the raw material in each kiln changes with a period of 180 °. Further, there is a phase difference of about 90 ° between the change in the scraping torque of the kiln A and the change in the scraping torque of the kiln B. This is because the positions of the partition walls of the respective kilns have a phase difference of 90 ° from each other. As a result, in the section where the scraping torque of the kiln A is maximum (kiln rotation angle around 160 °), the scraping torque of the kiln B is close to the minimum, and conversely, the section where the scraping torque of the kiln B is maximum (kiln rotation). At an angle of about 70 °, the scraping torque of the kiln A is close to the minimum.

  In the above example, the maximum scraping torque per kiln is about 20.2 (kN · m) (since the angle is set intermittently, some errors may be included. The same applies to the form). When this is simply doubled, it is about 40.3 (kN · m). By adding a phase difference to the change in the scraping torque of the two kilns as described above, the total of kiln A and kiln B The maximum value of the scraping torque is suppressed to about 26.5 (kN · m). This is a value that is reduced by about 34% compared to the case where the respective maximum values are simply added.

(Second Embodiment)
Next, a second embodiment of the present invention will be described with reference to FIG. 4 and FIG.

  FIG. 4 is a diagram showing a schematic configuration of a rotary kiln facility according to the second embodiment of the present invention. The rotary kiln facility 200 has two kilns 210a and 210b. Each of the kilns 210a and 210b is provided with partition walls 212a and 212b that divide the interior into four sections as lifters. In this embodiment, the raw material is charged in all four compartments.

  Here, as illustrated, the kilns 210a and 210b are disposed on the support roller 120 so that the positions of the partition walls 212a and 212b have a phase difference of 45 ° from each other. That is, for example, when the partition wall 212a is inclined at an angle of 45 °, the partition wall 212b is horizontal or vertical. Conversely, when the partition wall 212a is horizontal or vertical, the partition wall 212b is inclined at an angle of 45 °. As a result, the position distribution of the raw materials inside the kilns 210a and 210b changes at different phases.

  FIG. 5 is a graph showing changes in the scraping torque in the rotary kiln facility shown in FIG. In FIG. 5, the kiln 210 a is denoted as kiln A, and the kiln 210 b is denoted as kiln B. In this example, the scraping torque was calculated by sequentially rotating the kiln A and the kiln B at intervals of 5 ° while maintaining the phase difference of 45 ° between the positions of the partition walls 212a and 212b. The kiln and the raw material specifications (common to kiln A and kiln B) that are the calculation conditions are as shown in Table 4 below. Note that the amounts of raw materials present in the four compartments formed by the partition walls are all equal.

  Referring to the graph, it can be seen that both the kiln A and the kiln B change the scraping torque with a period of 90 ° (kiln rotation angle). This is because the position distribution of the raw materials in each kiln changes with 90 ° as a period. Further, there is a phase difference of about 45 ° between the change in the scraping torque of the kiln A and the change in the scraping torque of the kiln B. This is because the positions of the partition walls of the respective kilns have a phase difference of 45 ° from each other.

  In the above example, the maximum scraping torque per kiln is about 8.6 (kN · m). If this is simply doubled, it is about 17.3 (kN · m). However, because there is a phase difference in the change in the scraping torque of the two kilns as described above, the total of kiln A and kiln B The maximum value of the scraping torque is about 15.9 (kN · m), which is about 8% lower than when the maximum values are simply added.

(Third embodiment)
Subsequently, a third embodiment of the present invention will be described with reference to FIGS.

  FIG. 6 is a diagram showing a schematic configuration of a rotary kiln facility according to the third embodiment of the present invention. The rotary kiln facility 300 includes two kilns 310a and 310b. Each of the kilns 310a and 310b is provided with partition walls 212a and 212b that divide the interior into four sections as lifters. In the present embodiment, the raw material is charged in two of the four sections located diagonally.

  Here, as illustrated, the kilns 310a and 310b are arranged on the support roller 120 so that the positions of the partition walls 212a and 212b are synchronized (has no phase difference). At the same time, in the kilns 310a and 310b, the raw material is inserted into the alternate compartments. That is, for example, when the raw material is charged into the upper left and lower right compartments in the kiln 310a, the raw material is charged into the upper right and lower left compartments in the kiln 310b. As a result, the position distribution of the raw materials in the kilns 310a and 310b changes with phases different from each other.

  FIG. 7 is a graph showing changes in the scraping torque in the rotary kiln facility shown in FIG. In FIG. 7, the kiln 310 a is expressed as kiln A, and the kiln 310 b is expressed as kiln B. In this example, the kiln A and the kiln B were sequentially rotated at intervals of 10 ° to 15 ° in a state where the sections into which the raw materials were charged were staggered, and the scraping torque was calculated. In addition, the specifications of the kiln and the raw material (common to kiln A and kiln B), which are the calculation conditions, are as shown in Table 5 below. It is assumed that the amount of raw material existing in the two compartments into which the raw material is charged is equal.

  Referring to the graph, it can be seen that both the kiln A and the kiln B change the scraping torque with a period of 180 ° (kiln rotation angle). This is because the position distribution of the raw material in each kiln changes with a period of 180 °. Further, there is a phase difference of about 90 ° between the change in the scraping torque of the kiln A and the change in the scraping torque of the kiln B. This is because the positions of the sections where the raw materials are charged in each kiln have a phase difference of 90 ° from each other.

  In the above example, the maximum scraping torque per kiln is about 9.5 (kN · m). If this is simply doubled, it is about 19.0 (kN · m). However, since there is a phase difference in the change in the scraping torque of the two kilns as described above, the total of kiln A and kiln B The maximum value of the scraping torque is about 13.1 (kN · m), which is about 31% lower than when the maximum values are simply added.

(Fourth embodiment)
Next, a fourth embodiment of the present invention will be described with reference to FIG.

  FIG. 8 is a diagram showing a schematic configuration of a rotary kiln facility according to the fourth embodiment of the present invention. The rotary kiln facility 400 includes two kilns 410a and 410b. Each of the kilns 410a and 410b is provided with ridges 414a and 414b extending in the longitudinal direction of the kiln as lifters.

  Here, as illustrated, the kilns 410a and 410b are arranged on the support roller 120 so that the positions of the ridges 414a and 414b have a phase difference of 45 ° from each other. That is, for example, when the ridge 414a is inclined at an angle of 45 °, the ridge 414b is horizontal or vertical. Conversely, when the ridge 414a is horizontal or vertical, the ridge 414b is inclined at an angle of 45 °. As a result, the position distribution of the raw materials inside the kilns 410a and 410b changes at different phases.

  As in the present embodiment, even when a ridge is provided as a lifter, the scraping torque of each kiln changes periodically with the rotation of the kiln. For example, at the illustrated time point, in the kiln 410a, the raw material in the kiln 410a is scraped up to a position higher than the raw material in the kiln 410b by the protrusion 414a located in the lower left.

  Thus, even when the shape of the lifter is a ridge, by arranging the two kilns so that the positions of the ridges are different from each other, the position distribution of the raw materials inside each kiln is different from each other. It is possible to change. Therefore, also in this embodiment, the overall maximum scraping torque can be reduced as in the above embodiments.

(Fifth embodiment)
Next, a fifth embodiment of the present invention will be described with reference to FIG.

  FIG. 9 is a diagram showing a schematic configuration of a rotary kiln facility according to the fifth embodiment of the present invention. The rotary kiln facility 500 includes two kilns 110a and 110b. The configuration of the kilns 110a and 110b is the same as that in the first embodiment.

  The kilns 110a and 110b are respectively disposed on the support rollers 520. The support roller 520 supports the kiln 110b and supports the kiln 110b, the support roller 520b1 connected to the motor 130 via the speed reducer 140, the support roller 520b2 connected to the power transmission mechanism 550, and the kiln 110a. A support roller 520a1 that supports and is connected to the power transmission mechanism 550 and a support roller 520a2 that supports the kiln 110a are included.

  In the rotary kiln facility 500, the rotational power from the motor 130 is transmitted to the support roller 520b1 via the speed reducer 140, and the kiln 110b rotates as the support roller 520b1 rotates. On the other hand, the support roller 520b2 rotates with the rotation of the kiln 110b, and transmits the rotational power to the power transmission mechanism 550. The power transmission mechanism 550 transmits the rotational power from the support roller 520b2 to the support roller 520a1 without changing the rotation speed, and the kiln 110a rotates as the support roller 520a1 rotates. In this embodiment, the kilns 110a and 110b are thus connected to the motor 130, which is a common driving unit, and the phase difference of the position distribution of the raw materials inside the kilns 110a and 110b is maintained.

  As shown in the present embodiment, in the rotary kiln facility, how to arrange a common drive means for driving a plurality of kilns and a power transmission means between them is the spatial restriction of the installation location, It can be designed as appropriate from the viewpoint of ease of equipment maintenance. The arrangement of the drive means and the power transmission means in the present embodiment can be applied not only to the first embodiment but also to the second to fourth embodiments.

(Other embodiments)
In the embodiment described above, two kilns that share driving means are installed in the rotary kiln facility, but three or more kilns may be installed to share driving means. The arrangement of the drive means and the power transmission means in this case can also be designed as appropriate, for example, as in the first and fifth embodiments described above.

  In the embodiment described above, the partition wall provided as a lifter divides the inside of the kiln into two sections or four sections, but the number of sections is arbitrary. For example, the partition wall may divide the inside of the kiln into three sections or may be divided into five sections or more. However, when the number of sections is approximately 4 or less, the period of fluctuation of the scraping torque is somewhat long, so that the effect of reducing the scraping torque by adding a phase difference to the raw material position distribution is large. Moreover, the partition wall does not necessarily divide the inside of the kiln radially, for example, a part thereof may be divided concentrically.

  Moreover, in embodiment described above, although the protruding item | line provided as a lifter was provided in four places inside a kiln, the number of protruding item | lines is arbitrary. For example, the ridges may be provided at two or three locations inside the kiln, and may be provided at five or more locations. Further, the shape of the lifter is not limited to the partition wall or the ridge, and any shape may be used as long as the raw material in the kiln is scraped up.

  In the embodiment described above, the plurality of kilns all rotate in the same direction, but some of the plurality of kilns may rotate in the opposite direction.

  Further, in the driving method of a plurality of rotary kilns, the present invention arranges a plurality of rotary kilns so that the position distribution of the raw materials inside each rotary kiln changes with mutually different phases, so that the maximum rotational power required as a whole is obtained. Is reduced. In order to stably maintain the different phase changes, it is preferable to rotate the rotary kilns at the same speed. Therefore, the drive transmission of the rotary kiln is important. As described above, the rotational power of the kiln is transmitted by the rollers (or gears) provided around the outer wall surface of the kiln. Normally, the inventor has experienced that the kiln can be stably rotated without causing any slippage even in roller driving, but in the long-term use, a minute slip is generated and accumulated. There is a possibility that the position distribution of the raw material is shifted.

  In order to prevent this, it is necessary to check whether the position distribution of the raw materials in the plurality of rotary kilns is as originally set at the time of use, or the relative rotational positional relationship between the rotary kilns is initially set. It is preferable to adjust if there is a deviation (for example, attaching a detector to the outer periphery of the kiln and monitoring with a proximity sensor). Further, if driven by a gear, the position distribution of the raw material does not shift, which is preferable for preventing slippage. Such a correspondence makes it possible to maintain the initially set position distribution of the raw material.

  The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings, but the present invention is not limited to such examples. It is obvious that a person having ordinary knowledge in the technical field to which the present invention pertains can come up with various changes or modifications within the scope of the technical idea described in the claims. Of course, it is understood that these also belong to the technical scope of the present invention.

100, 200, 300, 400, 500 Rotary kiln equipment 110, 210, 310, 410 Kiln 112, 212 Partition wall 414 Projection 120, 520 Support roller 130 Motor 140 Reducer 550 Power transmission mechanism

Claims (6)

A method for driving a plurality of rotary kilns having lifters therein,
Provide a driving means common to the plurality of rotary kilns,
The rotary kiln driving method, wherein the plurality of rotary kilns are arranged so that the position distribution of the raw material in each rotary kiln changes at different phases.   The rotary kiln driving method according to claim 1, wherein two rotary kilns are driven.   The method of driving a rotary kiln according to claim 1 or 2, wherein the plurality of rotary kilns are arranged such that positions of the lifters with respect to the rotary kilns are different from each other. The lifter is a partition wall that divides the interior of the rotary kiln into a plurality of sections,
The rotary kiln according to any one of claims 1 to 3, wherein the plurality of rotary kilns are arranged so that positions of the sections into which the raw materials are charged are different from each other. Driving method.   The phase difference of the position distribution of the raw material among the plurality of rotary kilns is equal to a value obtained by dividing the period of the position distribution of the raw material by the number of the plurality of rotary kilns. The driving method of the rotary kiln of any one of Claims. The method for driving a rotary kiln according to any one of claims 1 to 5, wherein at least a part of the plurality of rotary kilns is rotated by being transmitted with power from the driving means via another rotary kiln.

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