Sintering ring cooling waste heat boiler steam temperature increasing system and ring cooling waste heat power generation system

Abstract

The utility model relates to the field of waste heat comprehensive utilization, and discloses a sintering ring cooling waste heat boiler steam temperature increasing system and a ring cooling waste heat power generation system.The sintering ring cooling waste heat boiler steam temperature increasing system comprises a waste heat boiler connected with a sintering ring cooling machine and a steam delivery pipeline connected with the waste heat boiler; a steam parameter monitoring device is arranged on the steam delivery pipeline; the device further comprises a superheater, a tube pass of the superheater is connected with a steam delivery pipeline, an air inlet and an air outlet of a shell pass of the superheater are connected with a flue gas pipeline of the gas boiler through a hot air pipe and an air return pipe respectively, and an induced draft fan is arranged on the air return pipe. According to the steam temperature increasing system designed by the utility model, high-temperature flue gas is led out from the gas boiler, and the steam of the waste heat boiler is heated by the superheater, so that the steam meets the steam inlet temperature requirement of a steam turbine, and the efficient utilization of the low-superheat-degree steam of the sintering ring cooling waste heat boiler is realized.

Description

Technical Field

[0001] The utility model relates to the field of comprehensive utilization of waste heat, in particular to a steam temperature raising system for a sintering ring-cooled waste heat boiler and a ring-cooled waste heat power generation system. Background Art

[0002] Most steel mills are equipped with sintering machines. After the sintered ore reacts violently in the sintering machine, its temperature reaches over 1000°C. The high-temperature ore enters the ring cooler. Through heat exchange between the cold air and the ore, the high-temperature hot air enters the waste heat boiler (HRSG). In the HRSG, the feed water absorbs heat, undergoes phase change, and becomes superheated, forming steam with a certain degree of superheat. The superheated steam generally enters the steam turbine to generate power. Due to adjustments in the sintering process and deterioration in the sealing performance of the ring cooler, the hot air volume and temperature of the sintering ring-cooled HRSG may decrease. Some sintering ring-cooled HRSGs are designed for a steam temperature of 380°C. After a period of operation, the steam temperature is only around 310°C, 70°C lower than the design value and lower than the minimum inlet steam temperature of the steam turbine. If the steam enters the steam turbine directly to generate power, the humidity in the last few stages of the blades will be too high, which may cause the blades to break. Therefore, when the steam temperature does not meet the turbine inlet requirements, the steam from the sintering ring-cooled waste heat boiler is generally cooled and decompressed before being incorporated into the low-pressure steam network, resulting in the inefficient use of this part of the steam.

[0003] Therefore, when the steam from the sintering ring-cooled waste heat boiler is lower than the turbine inlet steam temperature, how to increase the steam temperature to meet the turbine inlet steam requirements and ensure the safe and stable operation of the system is a common concern in the industry. Utility Model Content

[0004] The present utility model aims to solve the technical problems existing in the prior art. To this end, the utility model provides a steam temperature raising system for a sintering ring-cooled waste heat boiler. When the steam from the sintering ring-cooled waste heat boiler is lower than the inlet steam temperature of the steam turbine, the high-temperature flue gas generated by the gas boiler is used to raise the steam temperature, thereby achieving the purpose of steam entering the steam turbine to perform work. This ensures the safe and stable operation of the entire ring-cooled waste heat power generation system and fully utilizes the low-temperature steam from the sintering ring-cooled waste heat boiler.

[0005] The technical solution adopted by the utility model to solve its technical problems is:

[0006] In the first aspect, a steam temperature raising system for a sintering ring cooling waste heat boiler is provided, comprising a waste heat boiler connected to a sintering ring cooling machine, a steam exporting pipeline connected to the waste heat boiler, and a steam parameter monitoring device being provided on the steam exporting pipeline; and further comprising a superheater, wherein the tube side of the superheater is connected to the steam exporting pipeline, and the air inlet and air outlet of the shell side are connected to the flue gas pipeline of the gas boiler through a hot air pipe and a return air pipe respectively, wherein the return air pipe is provided with an induced draft fan.

[0007] In some optional embodiments, the steam parameter monitoring device includes a first temperature measuring device, a pressure measuring device and a flow meter.

[0008] In some optional embodiments, a steam regulating valve is further provided on the steam delivery pipeline for regulating the flow rate of the delivered steam.

[0009] In some optional embodiments, the hot air pipe extracts high-temperature flue gas of 500-600° C. in the flue gas duct.

[0010] In some optional embodiments, the hot air duct and the return air duct are respectively provided with a hot air regulating valve and a return air regulating valve.

[0011] In some optional embodiments, the steam outlet of the superheater is further provided with a second temperature measuring device.

[0012] In the second aspect, a ring-cooled waste heat power generation system is provided, comprising the sintering ring-cooled waste heat boiler steam temperature raising system and a steam turbine, wherein the steam output pipe of the sintering ring-cooled waste heat boiler steam temperature raising system is connected to the steam inlet main pipe of the steam turbine.

[0013] In some optional embodiments, the steam delivery pipeline is further provided with a bypass pipeline arranged in parallel with the superheater, the inlet and outlet ends of the superheater are both provided with isolation valves, and the bypass pipeline is provided with a bypass valve.

[0014] Compared with the prior art, the beneficial effects of the present invention are:

[0015] 1. The steam temperature raising system designed in this utility model draws high-temperature flue gas from the gas boiler and uses a superheater to heat the steam of the waste heat boiler, so that the steam meets the steam inlet temperature requirement of the steam turbine, realizing efficient utilization of the low-superheated steam of the sintering ring-cooled waste heat boiler. At the same time, the high-temperature flue gas drawn from the gas boiler releases heat and then returns to the flue gas pipeline of the gas boiler, making full use of the existing environmental protection facilities and reducing the operating costs of the entire system.

[0016] 2. The system sets a temperature measuring point at the superheater outlet, and sets regulating valves on the hot air duct and return air duct. This can adjust the flue gas flow rate according to the steam temperature at the superheater outlet. This ensures that the steam can meet the turbine inlet temperature requirements under different steam temperatures of the sintering ring-cooled waste heat boiler, thus achieving efficient utilization of the steam from the sintering ring-cooled waste heat boiler to feed the steam turbine for power generation.

[0017] 3. The steam parameter monitoring device and bypass pipe installed on the steam delivery pipe realize that when the outlet steam temperature of the sintering ring-cooled waste heat boiler reaches the turbine inlet steam temperature, the bypass valve of the bypass pipe is directly opened to allow the steam to enter the turbine steam inlet main pipe through the bypass pipe (at this time, the superheater is isolated by an isolation valve). BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work. Among them:

[0019] Figure 1 It is a structural diagram of the ring-cooling waste heat power generation system provided by the utility model.

[0020] In the accompanying drawings, the components represented by the reference numerals are as follows:

[0021] 1—waste heat boiler, 2—steam delivery pipeline, 3—steam turbine, 4—first temperature measuring device, 5—pressure measuring device, 6—flow meter, 7—superheater, 8—hot air duct, 9—return air duct, 10—flue gas duct, 11—induced draft fan, 12—steam regulating valve, 13—hot air regulating valve, 14—return air regulating valve, 15—second temperature measuring device, 16—bypass pipeline, 17—isolating valve, 18—bypass valve. DETAILED DESCRIPTION

[0022] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0023] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0024] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings and are only used to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific direction, be constructed or operate in a specific direction. Therefore, they should not be understood as limiting the present invention.

[0025] In addition, the descriptions involving the terms "first", "second", etc. in the present invention are for descriptive purposes only and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of such features. The terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a communication between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0026] In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by this utility model.

[0027] Example 1

[0028] A ring cooling waste heat power generation system, as shown in the attached Figure 1 As shown, the system includes a waste heat boiler 1 connected to a sintering ring cooler, a steam export pipeline 2 connected to the waste heat boiler, and a steam turbine 3. The steam export pipeline 2 is connected to the steam inlet main of the steam turbine 3. A steam parameter monitoring device is provided on the steam export pipeline 2 for real-time monitoring of steam parameters. Preferably, the steam parameter monitoring device includes a first temperature measuring device 4, a pressure measuring device 5, and a flowmeter 6, respectively for monitoring the temperature, pressure, and flow of the steam.

[0029] To address the issue of waste heat boiler steam being below the turbine inlet temperature, preventing the use of waste heat for power generation, this embodiment incorporates a superheater 7 on the steam delivery pipeline 2. The tube side of superheater 7 is connected to the steam delivery pipeline 2, while the air inlet and air outlet on its shell side are connected to the flue gas pipeline 10 of the gas boiler via a hot air duct 8 and a return air duct 9, respectively. Specifically, an induced draft fan 11 is provided on the return air duct 9. Preferably, the hot air duct extracts high-temperature flue gas at 500-600°C from the flue gas pipeline.

[0030] The superheater, hot air duct, return air duct, induced draft fan, etc. in this embodiment constitute the waste heat boiler steam temperature raising system. This system draws high-temperature flue gas from the gas boiler and uses the superheater to heat the waste heat boiler steam, so that the steam meets the steam inlet temperature requirement of the steam turbine, realizing efficient utilization of the low-superheated steam of the sintering ring-cooled waste heat boiler; at the same time, the high-temperature flue gas drawn from the gas boiler releases heat and returns to the flue gas duct of the gas boiler, fully utilizing the existing environmental protection facilities and reducing the operating costs of the entire system.

[0031] Preferably, the steam delivery pipe 2 is further provided with a steam regulating valve 12 for regulating the flow rate of delivered steam.

[0032] Preferably, the hot air pipe 8 and the return air pipe 9 are respectively provided with a hot air regulating valve 13 and a return air regulating valve 14, which can be used to adjust the flow rate of high-temperature flue gas extracted from the gas boiler.

[0033] Preferably, the steam outlet of the superheater 7 is further provided with a second temperature measuring device 15, which can provide guidance for flue gas flow regulation.

[0034] Example 2

[0035] Based on the first embodiment, as shown in the attached Figure 1 As shown, this embodiment further comprises a bypass pipe 16 provided on the steam delivery pipe 2 in parallel with the superheater 7. Isolation valves 17 are provided at the inlet and outlet ends of the superheater 7, and a bypass valve 18 is provided on the bypass pipe 16. Preferably, both the isolation valve 17 and the bypass valve 18 are electric valves.

[0036] Working Principle: When the steam parameter monitoring device detects that the steam temperature is lower than the turbine inlet temperature, the bypass valve closes and the two isolation valves open. The superheater is then used to heat the steam from the waste heat boiler to the required turbine inlet temperature. During this process, a second temperature measuring device monitors the steam temperature in real time and uses this temperature value to control the opening of the hot air control valve and the return air control valve to ensure that the steam temperature at the superheater outlet does not fall below the turbine inlet temperature.

[0037] When the steam parameter monitoring device detects that the steam temperature is not lower than the turbine inlet temperature, the two isolation valves are closed and the bypass valve is opened. At this time, the steam that reaches the turbine inlet temperature directly enters the turbine steam inlet main pipe.

[0038] The operation and control of the above facilities are all completed in the control room by the host computer automatic control.

[0039] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A steam temperature raising system for a sintering ring-cooled waste heat boiler, comprising a waste heat boiler connected to a sintering ring cooler, and a steam delivery pipeline connected to the waste heat boiler, wherein a steam parameter monitoring device is provided on the steam delivery pipeline; characterized in that: It also includes a superheater, the tube side of the superheater is connected to the steam delivery pipeline, and the air inlet and air outlet of the shell side are connected to the flue gas pipeline of the gas boiler through the hot air pipe and the return air pipe respectively, and the return air pipe is provided with an induced draft fan.

2. The steam temperature raising system for sintering ring cooling waste heat boiler according to claim 1 is characterized in that: The steam parameter monitoring device includes a first temperature measuring device, a pressure measuring device and a flow meter.

3. The steam temperature raising system for sintering ring cooling waste heat boiler according to claim 1 is characterized in that: The steam delivery pipeline is also provided with a steam regulating valve for regulating the flow rate of the delivered steam.

4. The steam temperature raising system for sintering ring-cooled waste heat boiler according to claim 1 is characterized in that: The hot air pipe extracts high-temperature flue gas of 500-600° C. in the flue gas pipeline.

5. The steam temperature raising system for sintering ring cooling waste heat boiler according to claim 1 is characterized in that: The hot air pipe and the return air pipe are respectively provided with a hot air regulating valve and a return air regulating valve.

6. The steam temperature raising system for sintering ring cooling waste heat boiler according to claim 1 is characterized in that: The steam outlet of the superheater is also provided with a second temperature measuring device.

7. A ring-cooled waste heat power generation system, characterized by: It comprises the steam temperature raising system of the sintering ring cooling waste heat boiler and the steam turbine as described in any one of claims 1 to 6, wherein the steam delivery pipe of the steam temperature raising system of the sintering ring cooling waste heat boiler is connected to the steam inlet main pipe of the steam turbine.

8. The ring-cooled waste heat power generation system according to claim 7, characterized in that: The steam delivery pipeline is further provided with a bypass pipeline arranged in parallel with the superheater. The inlet and outlet ends of the superheater are both provided with isolation valves, and the bypass pipeline is provided with a bypass valve.

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