JPH0247438Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to the structure of a rotary kiln for firing granulated pellets, and is particularly concerned with the structure of a rotary kiln for burning granulated pellets. (hereinafter simply referred to as kiln).

[Prior art]

Generally, a kiln for firing granulated pellets is equipped with a lifter 7 in the preheating area of the kiln, which has the function of raising the pellets and dispersing them into hot air to promote heat exchange. are doing.

[Problem that the invention attempts to solve]

When granulated pellets are fired in a conventional kiln equipped with a lifter in the preheating area, the free fall distance within the kiln is large, resulting in severe pulverization of the pellets, which may affect the properties of the pellets, the number of lifters, and Although it varies depending on the shape and operating conditions of the kiln, it has the disadvantage that it lowers the actual yield of the product and tends to promote welding between pellets in the same process.

[Means to solve the problem]

The present invention was developed in order to eliminate the above-mentioned drawbacks, and is designed to prevent the pellets from turning into powder in the kiln when granulated pellets are fired, and to perform efficient heat exchange. On top of the pellet layer charged in the kiln, a metal rod of a length such that the tip is always exposed is placed perpendicular to the inner wall of the refractory material over the entire preheating area, and in a plane orthogonal to the axis of rotation of the kiln. The kiln is installed at regular intervals in a plane parallel to the axis of rotation of the kiln.

[Effect]

Since the present invention is constructed in this way, when the pellets supplied from the hearth reach the preheating area, they enter a series of protruding metal rods, which restricts their rolling and causes them to spread onto the pellet layer. Since the amount of heat absorbed by the tip of the metal rod, which is always exposed, is appropriately transferred to the pellets via the metal rod, it is possible to significantly suppress the decline in actual yield due to pellet pulverization and welding.

[Example] Examples will be described in more detail below.

FIG. 1 is a sectional view of a kiln according to an embodiment of the present invention, and FIG. 2 shows a specific example of means for holding a large number of metal rods in cells of the kiln body.

In Fig. 1, 1 is a cell of the kiln main body, 2 is a refractory material, and 3 is a metal rod, which are arranged vertically from the inner wall of the refractory material 2 at approximately equal intervals in a plane perpendicular to the axis of rotation of the kiln. It is planted so as to protrude (that is, in the direction toward the center of the furnace in FIG. 1).

It is preferable that the metal rods 3 are installed over the entire preheating area of the kiln, with substantially equal intervals in the longitudinal direction and circumferential direction of the kiln, and arranged on the same plane parallel to the rotation axis. .

The length of the metal rod protruding from the refractory material must be such that its tip is always exposed on the surface of the rolling pellet layer.

The distance between the tips of the metal rods is preferably 4 to 6 times the maximum diameter of the charged pellets.

In addition, the tips of the metal rods installed in the refractory inner wall of the kiln may be connected in a lattice, diamond, ring, or chord shape as required, as shown in Figure 4 a, b, c, d, and e. , strength may be reinforced.

As a means for making a large number of metal rods protrude from the refractory inner wall of the kiln, for example, as shown in Fig. 2, a long rod 4 of stainless steel, for example, is placed on the inner wall of the cell 1 of the kiln in the same plane perpendicular to the rotation axis of the kiln. Weld the short rods 5 at equal intervals as shown in the figure, and divide the long rods 4 into equal parts by welding both ends of the short rods 5 to the metal wire 6. After welding with 4 and constructing one round in the circumferential direction of the kiln, the same construction was performed with equal spacing of the metal rods in the direction parallel to the rotation axis, and this was repeated to plant the metal rods all over the preheating area. .

[Effect of idea]

When operated with a kiln improved in this way, the pulverization rate and welding rate of pellets are significantly reduced compared to the conventional method using a lifter, the fuel consumption rate and yield are also significantly improved, and the operation is stable. It became like that.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a kiln preheating area, FIG. 2 is an example of holding a metal rod, FIG. 3 is a configuration diagram of a preheating area of a conventional kiln using a lifter, and FIG. 4 is an example of connecting the tips of metal rods. 1: Cell, 2: Refractory material, 3: Metal rod, 4: Long rod, 5: Short rod, 6: Metal wire, 7: Lifter.

Claims (1)

[Claims for Utility Model Registration] (1) In a rotary kiln for firing granulated pellets, a metal rod of a length such that its tip is always exposed above the charged pellet layer is installed on the inner wall of the refractory material over the entire preheating area. 1. A rotary kiln for pellet firing, characterized in that the pellets are installed at regular intervals in a plane perpendicular to the rotational axis of the rotary kiln and in a plane parallel to the rotational axis of the kiln. (2) The rotary kiln for pellet firing according to claim 1, wherein the distance between the tips of the metal rods is 4 to 6 times the maximum diameter of the pellets to be charged.