SU787855A1 - Rotary-furnace heat exchange apparatus - Google Patents

Description

(54) HEAT EXCHANGE DEVICE FOR ROTATING FURNACE

I

The invention relates to the building materials industry, in particular, to the technique of burning cement clinker in a rotary kiln.

A heat-exchanging device for a rotary kiln for firing a bulk material is known, which contains chiost | Furnaces through peresypn1 1 (. Ei.mepty, made in the form of truncated KOHvcoB, the outer surface of which;) are cutted by ribs located along a multiple helix. When the furnace is operating, the material but the entire height of its layer is captured by the large base of the cone and falls into its internal cavity. With further heating of the furnace and lifting, the material is poured over the inner cavity and the outer surface of the cone. The pouring of the material increases the contact between the material and the gas stream, as a result of which the heat exchange is improved 1). However, the filling elements of such devices are installed perpendicular to the gas flow, which hampers its movement. The heights;) of the pouring element narrows the flow area of the furnace, thus increasing the m,.) Is; gases and dust removal.

The closest in technical terms to the invention to be achieved is a heat exchange device containing hollow pouring elements mounted on the inner surface of the furnace lining, made variable in height with a twisting blade placed above the upper plane of the elements made in the form of boxes. In the projection of the sweep of the furnace body, the element has the form of a parallelogram or trapezium. When the furnace is rotated, the mattei., ..-. ,,, is captured by the first elements. Sign ..: CTC and pours out inside the linux n: OST1-. ; u4n. When immersed in a material, a known device with a lateral plane of the pouring e, tement and a twisting blade creates different

15 material speeds in c.ioe. therefore, the material is mixed more vigorously. When exiting the material, the pouring element twists the gas flow 2 with the side plane and the blade.

The disadvantage of the device is that the content in -leM is large 1 oli1; the properties of the transient viibix emethors are relatively complex con: tr to ii: i5, creating so many intersecting vortexes.

dust precipitation in the furnace. In addition, the acute angle of installation of the side plane of the pouring element relative to the axis of the furnace is limited by the required rate of discharge of material from the element, which in turn reduces the dust-collecting capacity of the device, impairs mixing of the material in the layer.

The purpose of the invention is to intensify heat transfer and reduce dust removal.

This goal is achieved by the fact that in the heat exchanger device of the rotary kiln of the furnace for firing bulk material, there are hollow pouring elements installed on the inner surface of the furnace lining, made variable by height with a twisting blade, the latter being installed at the end of the pouring element attached to the blade with one end by means of brackets to the furnace body, while changing the height of the pouring element along the length is 0, i-0.15 of the furnace radius.

FIG. 1 shows a heat exchange device, a cross section; in fig. 2 is a section A-A in FIG. one.

The device consists of transferring elements 1, in rows of circumferentially installed inner surface of the furnace body 2. The furnace body 2 is covered with a refractory lining 3. At the end of the pouring element 1, a twisting blade 4 is mounted, attached to the furnace body 2. The pouring element 1 is fixed at one end to the blade 4, and along the length of the brackets 5 attached to the furnace body 2. The bracket 5 in the pouring element 1 is made in the form of a partition passing through the cross-section of the pouring element 1, with each bracket 5 and adjacent to the furnace body 2, the plane of the blade 4 form a different angle with respect to the furnace axis.

The length of the filling element 1 is 0.5-2.0 times the diameter of the furnace. For more intensive mixing of the material, the pouring element 1 has a variable height along the length, while the height at the highest end of the pouring element 1 is 0.3-0.4 of the furnace radius. The height at the lower end of the pouring element is 0.15-0.30, the radius of the furnace. The pouring element 1 can be attached to the twisting blade 4 with both a higher and a lower end.

The height of the pouring element 1 at the highest end is determined by the height of the material layer in the furnace, while at the highest end, the pouring element 1 has a height (0.3-0.4 of the furnace radius), which ensures that element 1 is immersed in the material layer. At the lower end of the pouring element 1, the height (0.15-0.3 of the radius of the furnace) is determined by the rate of precipitation of the material from element 1, while the precipitation must occur through the bottom slit when the element 1 is raised. Thus, the height of the pouring element 1 varies along the length the value of 0.1 - 0.15 radius of the furnace provides maximum mixing of the material, therefore, the maximum heat transfer.

To reduce the effect on the pouring elements 1 of the gas flow passing along the length of the element 1 in the direction of the furnace axis, the height of the blade 4 has a value of 0.3-1 radius of the furnace, the angle of installation of the blades 4 relative to the axis of the furnace is 8-86 ° .

The height of the filling element 1 in the cross section of the furnace is not the same - the output internal cavity of the element 1, from which the material is poured out, is narrowed in comparison with the input cavity, by which the material is captured.

The device works as follows. ,

When the furnace is operating, the entrance cavity pours the filling element 1 into the material and fills it. When the furnace is rotated, the material through the narrowed slit of the exit cavity of the element 1 is poured into the space of the furnace. Since the filling element 1 has a variable height along the length, the exit slit along the length of the element 1 also has an unequal value and therefore the precipitation of the material from the element 1 is completed at an unequal angle of lift, which improves the mixing of the material in the layer. When filling the filling element 1 with a material, the angle between

0 separate brackets 5 and the blade 4 also contributes to the intensive mixing of the material in the layer. Intensive mixing of the material provides heat transfer intensification.

The blade 4 located in the end part of the pouring element 1 twists the passing gaseous medium into the screw flow, while a part of the material poured out from the element 1 is caught by the screw gas flow. The material particles picked up in the screw flow by an eccentric force move away from the center of the furnace and go into the internal cavity of the pouring elements 1. The bent surface of the pouring element 1 material particles are pressed to the lining 3, they lose speed

i and precipitated in the furnace.

The heat exchanger device consists of one or several rows of pouring elements 1 with blades 4 installed along the length of the furnace. If there are more than one row of pouring elements 1 with blades 4 in the heat exchanger, the distance between the individual rows is 0.5-3.0 of the furnace diameter.

The advantage of the proposed heat exchanger - intensification

J Heat transfer and improved dust collection in the furnace.

Claims (1)

Invention Formula Heat exchanging device of a rotary kiln for firing a bulk material containing