Waste heat efficient utilization system of sintering circular cooler

Abstract

The utility model discloses an efficient waste heat utilization system for a sintering circular cooler. Waste gas outlets of the section I and the section II of the circular cooler are communicated with a waste gas inlet of the waste heat boiler; a waste gas outlet of the waste heat boiler is communicated with an air inlet of the first circulating fan, and an air outlet of the first circulating fan is divided into two paths which are respectively communicated with an I-section air bellow and an II-section air bellow of the circular cooler to form flue gas and air circulation of the I-section air bellow and the II-section air bellow of the circular cooler; an air inlet of the first cooling fan is communicated with the outdoor environment; an air outlet of the first cooling fan is communicated with a V-section air box of the circular cooler; a section V waste gas outlet of the circular cooler is sequentially communicated with the second circulating fan and a section IV air box of the circular cooler; a section IV waste gas outlet of the circular cooler is sequentially communicated with the third circulating fan and a section III air box of the circular cooler; and a section III waste gas outlet of the circular cooler is communicated with a hot air cover of the sintering machine. According to the utility model, efficient utilization of high-grade heat energy is realized.

Description

Technical Field

[0001] The utility model relates to a system for efficiently utilizing waste heat of a sintering ring cooler. Background Art

[0002] In recent years, with the continuous improvement of national environmental protection requirements, steel companies have vigorously implemented technological transformation in accordance with the ultra-low emission requirements of atmospheric pollutants. Among them, the ring cooler, as a process of sintering and smelting, has long been emitting a large amount of dusty waste gas, especially in the medium and low temperature sections. Due to the low grade of waste heat, the recovery value is not as good as that in the high temperature section, so most steel companies do not recycle it. In the medium and low temperature sections, ring coolers are generally used to inhale cold air from the environment to cool the mine, and the medium and low temperature waste gas generated is directly discharged through the chimney. Under the current and even future increasingly stringent environmental protection situation, this treatment method will be gradually eliminated, and corresponding process improvements must be made to respond to policy requirements.

[0003] At present, zero emission of waste gas from annular coolers has been first implemented in Hebei and other regions, which has attracted close attention from relevant practitioners in the industry. It is expected that it will be gradually promoted to more provinces in the future. The waste gas from annular coolers contains a lot of dust particles and carries a lot of waste heat. How to balance waste heat recovery and pollutant control to achieve both economic and environmental benefits is a technical issue that steel companies are particularly concerned about. Utility Model Content

[0004] In view of the above problems, the utility model provides a system for efficiently utilizing waste heat of a sintering ring cooler with zero waste gas emission.

[0005] In order to achieve the above-mentioned purpose, the sintering ring cooler waste heat efficient utilization system of the utility model at least includes a ring cooler, a waste heat boiler, a first circulation fan, a first cooling fan, a second circulation fan, and a third circulation fan;

[0006] The annular cooler is divided into sections I, II, III, IV and V according to the temperature of the sintered ore from high to low. The exhaust gas outlets of sections I and II of the annular cooler are connected to the exhaust gas inlet of the waste heat boiler; the exhaust gas outlet of the waste heat boiler is connected to the air inlet of the first circulating fan, and the air outlet of the first circulating fan is divided into two routes, which are respectively connected to the wind boxes of sections I and II of the annular cooler, forming the smoke and air circulation of sections I and II of the annular cooler;

[0007] The air inlet of the first cooling fan is connected to the outdoor environment and draws natural air from the atmosphere; the air outlet of the first cooling fan is connected to the section V wind box of the ring cooler; the section V waste gas outlet of the ring cooler is connected to the second circulation fan and the section IV wind box of the ring cooler in sequence; the section IV waste gas outlet of the ring cooler is connected to the third circulation fan and the section III wind box of the ring cooler in sequence; the section III waste gas outlet of the ring cooler is connected to the hot air hood of the sintering machine.

[0008] Further, a multi-tube dust collector and an induced draft fan are sequentially arranged on the pipeline of the exhaust gas outlet of the third section of the annular cooler along the exhaust gas flow path.

[0009] Further, the exhaust gas outlet pipeline of the second section of the annular cooler is communicated with the inlet of the induced draft fan through a draft air pipe.

[0010] Further, a draft air valve is arranged on the draft air pipe for adjusting the amount of medium-temperature air draft from the exhaust gas of the second section of the annular cooler.

[0011] Further, a cold air supplement pipeline is arranged on the air inlet pipeline of the first circulation fan. One end of the cold air supplement pipeline is communicated with the outdoor environment, and the other end is communicated with the air inlet pipeline of the first circulation fan; a cold air valve is arranged on the cold air supplement pipeline for supplementing the air volume loss during the exhaust gas circulation of the first section and the second section of the annular cooler.

[0012] Further, the cold air valve and the draft air valve are of the regulating type.

[0013] Further, the first circulation fan, the first cooling fan, the second circulation fan, and the third circulation fan adopt variable frequency regulation.

[0014] Further, the waste heat boiler is a dual-pressure and dual-channel steam waste heat boiler. The high-temperature air inlet channel and the medium-temperature air inlet channel are respectively communicated with the exhaust gas outlet of the first section and the exhaust gas outlet of the second section of the annular cooler; the waste heat boiler generates steam of two qualities, high pressure and low pressure, which is used to drive a steam turbine to generate electricity or drive the main sintering exhaust fan.

[0015] To achieve the above object, the method for zero-emission collaborative waste heat high-efficiency utilization of the sintering annular cooler exhaust gas of the present utility model includes the following steps:

[0016] The high-quality waste heat of the first section and the second section of the annular cooler is recovered and utilized through the waste heat boiler 2, and the first circulation fan 3 provides the power for the smoke and air circulation of the first section and the second section of the annular cooler;

[0017] The relatively low-quality waste heat of the third section, the fourth section, and the fifth section of the annular cooler is subjected to cascade temperature increase through three-stage series connection, and medium-temperature hot air with a relatively high temperature and suitable for hot air sintering is generated at the outlet of the third section; the first cooling fan 6, the second circulation fan 7, and the third circulation fan 8 sequentially provide the kinetic energy heads of the exhaust gas in each section.

[0018] Further, it further includes the following steps:

[0019] In cold weather or when the temperature of the ore entering the circular cooler is relatively low, the first cooling fan 6, the second circulation fan 7, and the third circulation fan 8 operate with reduced air volume. At the same time, the air diversion valve 12 is opened, and the medium-temperature waste gas at the outlet of the second section of the circular cooler is mixed into the waste gas from the third section of the circular cooler to compensate for the reduction in the waste gas flow at the outlet of the third section of the circular cooler and the possible problem of relatively low air temperature, avoiding the adverse impact on the production of the sintering machine caused by the change of the operating conditions of this system.

[0020] Based on the concept of zero emission of waste gas from the circular cooler, this utility model fully combines the characteristics of segmented waste heat of the circular cooler, recovers the high- and medium-temperature waste heat of the circular cooler through a waste heat boiler to generate steam that can be used to drive a steam turbine for power generation or work, realizing the efficient utilization of high-grade heat energy; the medium- and low-temperature waste heat of the circular cooler is cascaded to increase the temperature to generate medium-temperature hot air with a relatively high temperature for hot air sintering, realizing the efficient utilization of medium- and low-temperature waste heat.

[0021] According to the temperature characteristics of the sintered ore, this utility model adopts stepped cooling. The sintered ore in the high-temperature section is cooled by air at a higher temperature, and the sintered ore in the low-temperature section is cooled by air at a lower temperature, which can reduce the breakage rate during the cooling process of the sintered ore and improve the finished product rate of the sintered ore.

[0022] This utility model is provided with a multi-tube dust collector and an induced draft fan to purify and pressurize the waste gas used for hot air sintering. Compared with the non-powered conveying method of directly introducing the waste gas into the hot air hood of the sintering machine, it increases the induced draft power and strengthens the implementation effect of hot air sintering; the setting of the multi-tube dust collector not only improves the production environment at the hot air hood of the sintering machine, but also increases the negative pressure at the inlet of the induced draft fan, providing conditions for the air diversion of the medium-temperature waste gas in the second section of the circular cooler (otherwise, it is difficult for the waste gas in the second section to be mixed into the waste gas pipeline in the third section).

[0023] This utility model designs reliable adjustment means. Through the opening and closing combination and operation coordination of the first cooling fan, the second circulation fan, the third circulation fan, and the air diversion valve, it can meet the requirements of different working conditions, and can achieve the "three simultaneous" benefits of sintered ore cooling, zero emission of waste gas, and efficient utilization of waste heat under various conditions.

[0024] This utility model is particularly applicable to the situation where the cooling requirements of the circular cooler (the outlet ore temperature does not exceed the allowable value) can be guaranteed by using three-stage series heat exchange in the third section, the fourth section, and the fifth section, and at the same time, the waste gas temperature in the third section does not exceed the upper limit of the allowable hot air temperature for hot air sintering. Description of the Drawings

[0025] Figure 1 It is a structural schematic diagram of a high-efficiency waste heat utilization system for a sintering circular cooler;

[0026] In the figure, 1 is a circular cooler; 2 is a waste heat boiler; 3 is a first circulation fan; 4 is a supplementary cold air pipeline; 5 is a cold air valve; 6 is a first cooling fan; 7 is a second circulation fan; 8 is a third circulation fan; 9 is a multi-tube dust collector; 10 is an induced draft fan; 11 is an air distribution pipe; 12 is an air distribution valve. Specific embodiments

[0027] The embodiments of the present utility model will be described in detail below with reference to the accompanying drawings.

[0028] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present utility model.

[0029] The terms "first" and "second" are only used for descriptive purposes, and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, unless otherwise specified, the meaning of "plurality" is two or more.

[0030] In the description of the present utility model, it should be noted that unless otherwise clearly defined and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a direct connection, or an indirect connection through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific situations.

[0031] Embodiment 1

[0032] A high-efficiency waste heat utilization system for a sintering circular cooler of the present utility model at least includes a circular cooler, a waste heat boiler, a first circulation fan, a first cooling fan, a second circulation fan, and a third circulation fan.

[0033] The circular cooler is divided into sections I, II, III, IV, and V according to the temperature of the sintered ore from high to low. The waste gas outlets of sections I and II of the circular cooler 1 are communicated with the waste gas inlets of the waste heat boiler 2; the waste gas outlet of the waste heat boiler 2 is communicated with the air inlet of the first circulation fan 3, and the air outlet of the first circulation fan 3 is divided into two paths, which are respectively communicated with the air boxes of sections I and II of the circular cooler 1, forming a flue gas and air circulation in sections I and II of the circular cooler.

[0034] The air inlet of the first cooling fan 6 communicates with the outdoor environment to suck natural air from the atmosphere; the air outlet of the first cooling fan 6 communicates with the V-section air box of the annular cooler 1; the V-section waste gas outlet of the annular cooler 1 is successively communicated with the second circulation fan 7 and the IV-section air box of the annular cooler 1; the IV-section waste gas outlet of the annular cooler 1 is successively communicated with the third circulation fan 8 and the III-section air box of the annular cooler 1; the III-section waste gas outlet of the annular cooler 1 is communicated with the hot air hood of the sintering machine to send medium-temperature waste gas above the sintering material surface for hot air sintering;

[0035] Example 2

[0036] As an improvement of the above embodiment, on the pipeline after the mixing point of the III-section waste gas outlet and the V-section waste gas outlet of the annular cooler 1, a multi-tube dust collector 9 and a induced draft fan 10 are successively arranged along the waste gas flow. The multi-tube dust collector 9 is used to remove dust particles in the waste gas, and the induced draft fan 10 is used to overcome the frictional resistance along the waste gas pipeline to send the waste gas to the hot air hood of the sintering machine;

[0037] Example 3

[0038] As an improvement of the above embodiment, the II-section waste gas outlet pipeline of the annular cooler 1 is communicated with the inlet of the induced draft fan 10 through a draft air pipe 11; a draft air valve 12 is arranged on the draft air pipe 11 to adjust the medium-temperature air volume drawn from the II-section waste gas of the annular cooler;

[0039] Example 4

[0040] As an improvement of the above embodiment, a cold air supplement pipeline 4 is arranged on the air inlet pipeline of the first circulation fan 3. One end of the cold air supplement pipeline 4 communicates with the outdoor environment, and the other end communicates with the air inlet pipeline of the first circulation fan 3; a cold air valve 5 is arranged on the cold air supplement pipeline 4 to supplement the air volume loss during the waste gas circulation in the I-section and II-section of the annular cooler 1;

[0041] In the above embodiments, the cold air valve 4 and the draft air valve 11 are both of the regulating type; the first circulation fan 3, the first cooling fan 6, the second circulation fan 7, and the third circulation fan 8 all adopt variable frequency regulation;

[0042] The waste heat boiler 2 is a dual-pressure and dual-channel steam waste heat boiler. The high-temperature air inlet channel and the medium-temperature air inlet channel are respectively communicated with the I-section waste gas outlet and the II-section waste gas outlet of the annular cooler 1; the waste heat boiler 2 generates two qualities of steam, high pressure and low pressure, for driving a steam turbine to generate electricity or driving the main exhaust fan of the sintering machine.

[0043] Example 5

[0044] The operation method of the above system is as follows:

[0045] The high-quality waste heat from the first and second sections of the annular cooler is recovered and utilized through the waste heat boiler 2, and the first circulation fan 3 provides the power for the flue gas and air circulation in the first and second sections of the annular cooler;

[0046] The relatively low-quality waste heat from the third, fourth, and fifth sections of the annular cooler is cascaded in three stages to achieve cascade temperature increase, generating medium-temperature hot air with a relatively high temperature at the outlet of the third section, which can be used for hot air sintering; the first cooling fan 6, the second circulation fan 7, and the third circulation fan 8 sequentially provide the kinetic energy heads of the exhaust gas flow in each section;

[0047] Under most operating conditions, the air-distributing valve 12 does not need to be opened, and the hot air meeting the requirements of hot air sintering can be generated by the three-stage cascade of the third, fourth, and fifth sections of the annular cooler; in cold weather, or when the temperature of the ore entering the annular cooler is relatively low, etc., the first cooling fan 6, the second circulation fan 7, and the third circulation fan 8 operate with reduced air volume, and at the same time the air-distributing valve 12 is opened, and the medium-temperature hot exhaust gas at the outlet of the second section of the annular cooler is mixed into the exhaust gas from the third section of the annular cooler to compensate for the reduction in the exhaust gas flow at the outlet of the third section of the annular cooler and the possible low air temperature, so as to avoid the adverse impact on the production of the sintering machine caused by the change of the operating conditions of this system.

[0048] The above has described the present utility model in detail with reference to the accompanying drawings. However, the present utility model is not limited to the above embodiments. Within the knowledge scope of those of ordinary skill in the art, various changes can be made without departing from the purpose of the present utility model. Many other changes and modifications made without departing from the concept and scope of the present utility model should be regarded as within the protection scope of the present utility model.

[0049] In the description of this specification, specific features, structures, materials, or characteristics can be combined in a suitable manner in any one or more embodiments or examples.

[0050] The above is only the specific embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present utility model can easily think of changes or substitutions, which should all be covered within the protection scope of the present utility model. Therefore, the protection scope of the present utility model should be subject to the protection scope of the claims.

Claims

1. A high-efficiency waste heat utilization system for a sintering annular cooler, characterized in that, It includes at least a ring cooler, a waste heat boiler, a first circulation fan, a first cooling fan, a second circulation fan, and a third circulation fan; The ring cooler is divided into section Ⅰ, section Ⅱ, section Ⅲ, section Ⅳ, and section Ⅴ according to the decreasing temperature of the sintered ore. The waste gas outlets of section Ⅰ and section Ⅱ of the ring cooler are connected to the waste gas inlets of the waste heat boiler; the waste gas outlet of the waste heat boiler is connected to the air inlet of the first circulation fan. The air outlet of the first circulation fan is divided into two paths, respectively connected to the air boxes of section Ⅰ and section Ⅱ of the ring cooler, forming a flue gas and air circulation for section Ⅰ and section Ⅱ of the ring cooler; The air inlet of the first cooling fan is connected to the outdoor environment to suck natural air from the atmosphere; the air outlet of the first cooling fan is connected to the air box of section Ⅴ of the ring cooler; the waste gas outlet of section Ⅴ of the ring cooler is successively connected to the second circulation fan and the air box of section Ⅳ of the ring cooler; the waste gas outlet of section Ⅳ of the ring cooler is successively connected to the third circulation fan and the air box of section Ⅲ of the ring cooler; the waste gas outlet of section Ⅲ of the ring cooler is connected to the hot air hood of the sintering machine.

2. The waste heat highly efficient utilization system of a sintering annular cooler according to claim 1, characterized in that A multi-tube dust collector and an induced draft fan are successively arranged on the pipeline of the waste gas outlet of section Ⅲ of the ring cooler along the waste gas flow direction.

3. The waste heat high-efficiency utilization system of a sintering annular cooler as described in claim 2, characterized in that The waste gas outlet pipeline of section Ⅱ of the ring cooler is connected to the inlet of the induced draft fan through a diverting air pipe.

4. The waste heat high-efficiency utilization system of a sintering annular cooler according to claim 3, characterized in that, A diverting air valve is arranged on the diverting air pipe for adjusting the amount of medium-temperature air diverted from the waste gas of section Ⅱ of the ring cooler.

5. The high-efficiency waste heat utilization system for a sintering ring cooler according to claim 1, wherein A cold air supplement pipeline is arranged on the air inlet pipeline of the first circulation fan. One end of the cold air supplement pipeline is connected to the outdoor environment, and the other end is connected to the air inlet pipeline of the first circulation fan; a cold air valve is arranged on the cold air supplement pipeline for supplementing the air volume loss during the waste gas circulation of section Ⅰ and section Ⅱ of the ring cooler.

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