RU2335721C1 - Circular furnace - Google Patents

Abstract

FIELD: heating.

SUBSTANCE: circular furnace contains siege and burners located between load packages. Injection-type burners are located in furnace hearth recesses overlapped with fire-proof material having openings for burner installation so that high-temperature part of flame is near furnace hearth. Furnace design is represented as two rectangular roasting channels interconnected along edges by channels of smaller cross section and intended for coolant transfer from one channel into another; corner chambers are provided with end injection-type burners ensuring direct coolant movement in roasting channels and in corner chambers.

EFFECT: improvement of roasted brick quality; constant coolant temperature along roasting channel decrease of fuel consumption.

4 dwg

Description

The invention relates to the production of building material, and more specifically to a device for firing ceramic bricks.

Known annular kiln containing a removable summary sections of a rectangular shape, a smoke exhauster, gas ducts, a hearth, fuel holes with covers in sections, damper overlap the end of the sections, as well as angular removable summary sections made in the form of a rectangular triangle, the sides of which are equal to the outer sides of rectangular removable composite sections (RF №2151353, F27В 13/00).

Closest to the technical nature of the claimed furnace is an annular kiln containing a canalized hearth and burners placed in the arch of the furnace between the packages of the charge, equipped with a nozzle made of lumpy refractory material placed on the bottom in the intervals between the packages of the charge, while the bottom is made canalized along the entire length furnaces (RF №2023970, F27В 13/06).

However, due to the fact that the high-temperature zone of the burner of the known furnace is at the top, the underwater part will always have a higher temperature than the hearth. Such a design allows only partially reducing the temperature difference between the upper and lower zones, which leads to obtaining fired bricks of a heterogeneous quality and the use of additional fuel.

The objective of the invention is to improve the quality of the fired brick both in strength characteristics and in color by achieving uniform firing inside the chambers (eliminating temperature differences between the upper and lower parts of the furnace), ensuring a constant temperature of the coolant throughout the firing channel and reducing fuel consumption.

The essence of the invention lies in the fact that the annular furnace comprises, underneath, injection-type burners located between the charge packages in the niches of the furnace hearth, covered by refractory material having openings for installing the burner, so that the highest-temperature part of the torch is located near the furnace hearth; in shape, the furnace consists of two rectangular calcining channels connected at the edges by channels of a smaller section, designed to transfer the coolant from one channel to another; the corner chambers are equipped with injection-type end burners, which ensure the coolant moves in a straight line in the firing channels and in the corner chambers.

The proposed device allows to reduce fuel consumption and to obtain a brick of uniform quality in terms of both strength characteristics and color. The use of injection-type burners, working on the principle of preliminary mixing of gas and air, allows you to accelerate the flow of physical and chemical firing processes, to ensure the formation of a reducing environment in the raw brick itself. Due to the use of injection-type burners in the niches of the furnace hearth in the recessed channels, the heated air is circulated qualitatively inside the chambers due to natural convection flows, as well as when used in the corner chambers of the furnace, which in shape is two rectangular calcining channels connected at the edges by channels of a smaller section Injection-type end burners ensure uniform distribution of the coolant temperature throughout the entire calcination channel.

The invention is illustrated by drawings, where figure 1 schematically shows a ring furnace, a plan; figure 2 is a section aa.

Brick firing is carried out in a ring furnace 1. Brick packages 2 are located inside the firing channel 3, which is blocked by a refractory vault 4. In the gaps between the brick packages 2 are injection-type burners 5, which are structurally located in the recesses of the hearth 6 of furnace 1. The niches are covered with refractory material 7 having holes for installing the burners 5. The firing channels 3 are connected at the edges by channels of a smaller cross section 8, designed to transfer the coolant from one firing channel 3 of the furnace 1 to another. The corner chambers 9 of the furnace are equipped with end burners 10 of the injection type.

After installing the packages with brick 2 in the annular furnace 1, the calcining channel 3 is blocked by the refractory arch 4, injection-type burners 5 are turned on. The most high-temperature part of the torch of the burner 5 is located near the hearth 6 of the furnace 1, and since the hot heat carrier always rises up, its high-quality circulation is ensured over the cross-section of the burning channel 3 of the ring furnace 1. Moving the fire from one line of burners 5 to another, brick is fired. After firing at the end of one firing channel 3 of the ring furnace 1, the coolant is transferred through the channel of smaller cross section 8 to the opposite firing channel 3, and the firing process is repeated. At the same time, in the corner chambers 9, injection-type end burners 10 are turned on and the coolant moves in a straight line both in the firing channels 3 and in the corner chambers 9, which ensures uniform (with the same temperature) firing of bricks.

The use of the proposed furnace allows, in comparison with the prototype, to reduce fuel consumption, to improve the quality of the fired brick both in strength characteristics and in color. This achieves a technical result, which is confirmed by the test results, which were carried out on the existing technological line for the production of semi-dry pressed ceramic bricks at a factory in the village of Chaltyr, Rostov Region. Loam from the Sukho-Chaltyr deposit was used as raw material. The manufacture of products was carried out taking into account the properties of this raw material and the necessary technological parameters of production, which were obtained during laboratory tests.

The test results of the calcined products, as well as data on the flow rate of the gas used are shown in table 1.

Table 1 Oven Compressive strength, MPa Bending Strength, MPa Color uniformity of products

Fuel consumption,

Famous 14.0 2.1 Not reached 385.63 / 325.16 Declared 17.0 2,3 Uniform coloring 278.53 / 234.8

Due to the use in the corner chambers of the furnace, which is in the form of two rectangular calcining channels connected along the edges of the channels of a smaller cross-section, the injection-type end burners provide a constant coolant temperature at all points of the calcining channel. The movement diagram of the temperature curves of the known and claimed annular furnaces are presented in figure 3 and figure 4.

Claims (1)

An annular furnace containing underneath, burners located between the packages of the charge, characterized in that the injection-type burners are located in the niches of the furnace hearth, covered with refractory material having openings for installing the burner, so that the highest-temperature part of the torch is located near the furnace bottom; in shape, the furnace consists of two rectangular calcining channels connected at the edges by channels of a smaller section, designed to transfer the coolant from one channel to another; the corner chambers are equipped with injection-type end burners, which ensure the coolant moves in a straight line in the firing channels and in the corner chambers.

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