Blast furnace slag flushing water waste heat utilization system and control method thereof

Abstract

The invention discloses a blast furnace slag flushing water waste heat utilization system and a control method thereof. The system comprises target equipment with an inflow port and an outflow port; the blast furnace is provided with at least two slag outlets; the multiple heat exchange stations are connected with the at least two slag outlets in a one-to-one correspondence mode, each heat exchange station is provided with a hot inlet, a hot outlet, a cold inlet and a cold outlet, the hot inlets and the hot outlets are communicated with the slag outlets, and the multiple heat exchange stations are connected in series through the cold inlets and the cold outlets; the cold inlet of the heat exchange station located at the head end of series connection is controllably communicated with the outflow port, and the cold outlet of the heat exchange station located at the tail end of series connection is controllably communicated with the inflow port. The heat exchange stations correspondingly connected with the slag outlet are arranged in series, so that when the slag outlet of the blast furnace discharges slag alternately, slag water heat can be continuously extracted for waste heat utilization all the time, and meanwhile, the influence of slag water temperature change on target equipment when the slag outlet discharges slag alternately is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of blast furnace waste heat utilization, and in particular to a blast furnace slag flushing water waste heat utilization system and a control method thereof. Background Art

[0002] A large amount of waste heat is generated during the production process of the steel industry. Driven by energy conservation, emission reduction and improving corporate economic benefits, medium and high temperature waste heat has been basically recovered. However, low-temperature waste heat media are mostly ignored and wasted due to their low quality, complex composition, high impurity content, corrosiveness in some parts, poor recovery efficiency, and limitations of current recovery technology levels and material properties. Specifically, blast furnace slag flushing water, process circulating cooling water and industrial wastewater with a certain amount of waste heat are mostly wasted.

[0003] From the perspective of the steel production process, blast furnace ironmaking is the process with the highest energy consumption in steel production, accounting for about 70% to 80% of the total energy consumption of the entire steel production process. Every ton of pig iron produced produces about 0.3t to 0.6t of blast furnace slag, with a temperature of up to 1450℃ to 1500℃. Each ton of blast furnace slag contains about (1.26 to 1.88)×106kJ of sensible heat, equivalent to 0.04t to 0.06t of standard coal. The hydraulic slag flushing process of blast furnace slag will produce slag flushing water at 70℃ to 90℃. This water is repeatedly reused after being pressurized and sent to the cooling tower for cooling, resulting in a large waste of waste heat resources.

[0004] At present, the waste heat recovery system of slag flushing water recovers the waste heat of slag flushing water by setting up a waste heat recovery device, and transmits it to the users of the heat network for use. However, large blast furnaces usually use two or more slag outlets, and when the blast furnace is in continuous operation, the slag outlet is usually a single outlet for slag discharge, that is, the slag outlet on one side is used for slag discharge, and the inactive slag outlet on the other side does not discharge slag during this period, and the slag outlet needs to be switched every about 2 hours, and there will be a 40-minute alternation time during this period. The temperature of the slag flushing water at the corresponding slag outlet will also change. After the switch, the temperature of the slag flushing water in the used slag outlet gradually increases, and the temperature of the slag flushing water in the inactive slag outlet gradually decreases. As a result, when multiple slag outlets are alternately discharged, the temperature change of the slag flushing water will cause temperature fluctuations at the users of the heat network.

[0005] Therefore, how to reduce the impact of slag water temperature changes caused by intermittent operation of slag water due to slag outlet switching on temperature fluctuations at heating network users on the basis of recovering the waste heat of blast furnace slag flushing water is a technical problem faced by technical personnel in this field. Summary of the invention

[0006] The purpose of the present invention is to provide a blast furnace slag flushing water waste heat utilization system and a control method thereof, so as to improve the problem of temperature fluctuation at the heat network user caused by slag outlet switching in the prior art.

[0007] The above-mentioned purpose of the present invention can be achieved by adopting the following technical solutions:

[0008] The present invention provides a blast furnace slag flushing water waste heat utilization system, comprising: a target device having an inlet and an outlet; a blast furnace having at least two slag outlets; a plurality of heat exchange stations connected to the at least two slag outlets in a one-to-one correspondence, the heat exchange stations having a hot inlet, a hot outlet, a cold inlet and a cold outlet, the hot inlet and the hot outlet being connected to the slag outlet, a plurality of the heat exchange stations being connected in series via the cold inlet and the cold outlet, the cold inlet of the heat exchange station located at the head end of the series connection being controllably connected to the outflow outlet, and the cold outlet of the heat exchange station located at the end of the series connection being controllably connected to the inlet.

[0009] Specifically, the slag flushing water circulates between the slag outlet and the corresponding heat exchange station connected thereto, and exchanges heat between the heat exchange station and the circulating medium of the target equipment; the circulating medium of the target equipment flows through all the heat exchange stations in sequence, and exchanges heat with the slag flushing water in the heat exchange station connected to the slag outlet of the blast furnace that is in a slag discharging state.

[0010] Furthermore, the blast furnace slag flushing water waste heat utilization system also includes a refrigerator, which has a driving heat source inlet, a driving heat source outlet, a target medium inlet and a target medium outlet, the driving heat source inlet is controllably connected to the cold outlet of the heat exchange station located at the end of the series, the driving heat source outlet is controllably connected to the cold inlet of the heat exchange station located at the head end of the series, the target medium inlet is controllably connected to the outflow outlet, and the target medium outlet is controllably connected to the inflow inlet.

[0011] Preferably, the blast furnace has a first slag outlet and a second slag outlet, the heat exchange station corresponding to the first slag outlet is the first heat exchange station, the heat exchange station corresponding to the second slag outlet is the second heat exchange station, the cold inlet of the first heat exchange station is controllably connected to the outflow outlet, the cold inlet of the second heat exchange station is connected to the cold outlet of the first heat exchange station, and the cold outlet of the second heat exchange station is controllably connected to the inflow inlet; the target medium inlet is controllably connected to the outflow outlet, the driving heat source inlet is controllably connected to the cold outlet of the second heat exchange station, the driving heat source outlet is controllably connected to the cold inlet of the first heat exchange station, and the target medium outlet is controllably connected to the inflow inlet.

[0012] Preferably, the target device has a cold source demand state and a heat source demand state. In the heat source demand state, the refrigerator is in a closed state, the cold inlet of the first heat exchange station is connected to the outflow outlet, and the cold outlet of the second heat exchange station is connected to the inflow inlet; in the cold source demand state, the refrigerator is in an open state, the target medium inlet is connected to the outflow outlet, the driving heat source inlet is connected to the cold outlet of the second heat exchange station, the driving heat source outlet is connected to the cold inlet of the first heat exchange station, and the target medium outlet is connected to the inflow inlet.

[0013] Preferably, an outflow pipe is connected between the cold inlet and the outflow outlet of the first heat exchange station, an inflow pipe is connected between the cold outlet and the inflow of the second heat exchange station, the target medium inlet is connected to the outflow pipe through an outflow branch pipe, the driving heat source inlet is connected to the cold outlet of the second heat exchange station through a first connecting pipe, the driving heat source outlet is connected to the outflow pipe through a second connecting pipe, and the target medium outlet is connected to the inflow pipe through an inflow branch pipe; a first cutting mechanism is provided on the outflow pipe between the outflow branch pipe and the second connecting pipe, a second cutting mechanism is provided on the inflow pipe between the inflow branch pipe and the cold outlet of the second heat exchange station, a third cutting mechanism is provided on the first connecting pipe, a fourth cutting mechanism is provided on the second connecting pipe, a fifth cutting mechanism is provided on the outflow branch pipe, and a sixth cutting mechanism is provided on the inflow branch pipe.

[0014] Preferably, the first cut-off mechanism, the second cut-off mechanism, the third cut-off mechanism, the fourth cut-off mechanism, the fifth cut-off mechanism and the sixth cut-off mechanism are all manual switch valves. When the target device is in a cold source demand state, the first cut-off mechanism and the second cut-off mechanism are in an open state, and the third cut-off mechanism, the fourth cut-off mechanism, the fifth cut-off mechanism and the sixth cut-off mechanism are in a closed state; when the target device is in a hot source demand state, the first cut-off mechanism and the second cut-off mechanism are in a closed state, and the third cut-off mechanism, the fourth cut-off mechanism, the fifth cut-off mechanism and the sixth cut-off mechanism are in an open state.

[0015] Preferably, the first cut-off mechanism, the second cut-off mechanism, the third cut-off mechanism, the fourth cut-off mechanism, the fifth cut-off mechanism and the sixth cut-off mechanism are all electric switch valves. After obtaining the cold source demand state signal of the target device, the first cut-off mechanism and the second cut-off mechanism enter the disconnected state, and the third cut-off mechanism, the fourth cut-off mechanism, the fifth cut-off mechanism and the sixth cut-off mechanism enter the closed state; after obtaining the hot source demand state signal of the target device, the first cut-off mechanism and the second cut-off mechanism enter the closed state, and the third cut-off mechanism, the fourth cut-off mechanism, the fifth cut-off mechanism and the sixth cut-off mechanism enter the disconnected state.

[0016] Preferably, outer walls of the outflow pipe, the inflow pipe, the outflow branch pipe, the inflow branch pipe, the first connecting pipe, and the second connecting pipe are all provided with a fire-resistant heat-insulating material layer.

[0017] Preferably, the refractory heat-insulating material layer is a refractory heat-insulating coating applied to the outer wall of the pipeline, or the refractory heat-insulating material layer is a refractory heat-insulating cotton coated on the outer wall of the pipeline.

[0018] Another object of the present invention is to provide a control method for the blast furnace slag flushing water waste heat utilization system as described above, comprising: obtaining a demand state signal of the target device; sending a corresponding action signal to each electric switch valve based on the demand state signal of the target device; each electric switch valve performs a corresponding action based on the received action signal to enter a closed state or an open state; wherein the demand state signal of the target device includes a heat source demand state signal and a cold source demand state signal, and the action signal includes a closed action signal and an open action signal, and when the demand state signal of the target device is a cold source demand state signal, an open action signal is sent to the first cut-off mechanism and the second cut-off mechanism, and a closed action signal is sent to the third cut-off mechanism, the fourth cut-off mechanism, the fifth cut-off mechanism, and the sixth cut-off mechanism; when the demand state signal of the target device is a heat source demand state signal, a closed action signal is sent to the first cut-off mechanism and the second cut-off mechanism, and an open action signal is sent to the third cut-off mechanism, the fourth cut-off mechanism, the fifth cut-off mechanism, and the sixth cut-off mechanism.

[0019] The characteristics and advantages of the present invention are: the blast furnace slag flushing water waste heat utilization system provided by the present invention connects the heat exchange stations connected with the slag outlets in series one by one, so that the circulating medium of the target equipment flows through all the heat exchange stations in sequence, so that it can exchange heat with the blast furnace slag flushing water in the heat exchange station connected with the current slag outlet when the blast furnace is in a slag discharging state, so that when the slag outlets of the blast furnace are alternately discharging slag, the heat of the slag water can be continuously extracted for waste heat utilization, and at the same time, the influence of the slag water temperature change when the blast furnace slag outlets are alternately discharging slag on the target equipment is reduced, and the waste heat utilization rate of the blast furnace slag flushing water is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0021] Figure 1 It is a schematic diagram of the composition of the blast furnace slag flushing water waste heat utilization system provided in an embodiment of the present invention.

[0022] Description of Figure Numbers:

[0023] 1. Blast furnace; 11. First slag outlet; 12. Second slag outlet;

[0024] 2. The first heat exchange station;

[0025] 3. The second heat exchange station;

[0026] 4. Target device;

[0027] 5. Refrigerator;

[0028] 10. Outflow pipe;

[0029] 20. Inflow pipe;

[0030] 30. Outflow branch;

[0031] 40. a first connecting pipeline;

[0032] 50. A second connecting pipeline;

[0033] 60. Inflow into the branch pipe;

[0034] K1, the first cutting mechanism;

[0035] K2, the second cutting mechanism;

[0036] K3, the third cutting mechanism;

[0037] K4, fourth cutting mechanism;

[0038] K5, the fifth cutting mechanism;

[0039] K6, the sixth cutting mechanism. DETAILED DESCRIPTION

[0040] The following will be combined with the 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 described embodiments 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 creative work are within the scope of protection of the present invention.

[0041] like Figure 1 As shown, the present invention provides a blast furnace slag flushing water waste heat utilization system, including a blast furnace 1, a heat exchange station and a target device 4, and the heat exchange station is connected between the blast furnace 1 and the target device 4. Among them, the target device 4 has an inlet and an outlet, the blast furnace 1 has at least two slag outlets, and the heat exchange station is a plurality of stations connected one-to-one with the at least two slag outlets. The heat exchange station has a hot inlet, a hot outlet, a cold inlet and a cold outlet, and the hot inlet and the hot outlet are connected with the slag outlet. The plurality of heat exchange stations are connected in series through the cold inlet and the cold outlet, that is, in the direction from the first end of the series to the end of the series, the cold outlet of the previous heat exchange station is connected to the cold inlet of the next heat exchange station, the cold inlet of the heat exchange station located at the first end of the series is controllably connected to the outlet, and the cold outlet of the heat exchange station located at the end of the series is controllably connected to the inlet. Specifically, the blast furnace slag flushing water circulates between the slag outlet and the corresponding heat exchange station connected thereto, and returns to the slag flushing outlet for the next slag flushing after heat exchange and cooling in the heat exchange station and the circulating medium of the target device 4. The circulating medium of the target device 4 flows through a plurality of heat exchange stations arranged in series in sequence, and returns to the target device 4 after heat exchange and heating in the heat exchange station connected to the current slag outlet of the blast furnace 1 when the slag is being discharged. In this way, the waste heat of the slag flushing water is used to heat the circulating medium of the target device 4, so as to be supplied to the heat users. Preferably, at least one plate heat exchanger is provided in the heat exchange station. Specifically, blast furnace slag flushing water flows into the hot inlet of the plate heat exchanger through the slag water outflow pipe 10, and the circulating medium of the target equipment 4 flows into the cold inlet of the plate heat exchanger. After the two exchange heat in the plate heat exchanger, the blast furnace slag flushing water returns to the slag flushing port from the hot outlet of the plate heat exchanger through the slag water reflux pipe, and the circulating medium of the target equipment 4 returns to the target equipment 4 from the cold outlet of the plate heat exchanger. The cycle is repeated in this way to realize the utilization of waste heat of blast furnace slag flushing water.

[0042] Among them, the target device 4 can be a multi-attribute device with a cold source demand state and a heat source demand state, or it can be a single-attribute device with only a cold source demand state or a heat source demand state. When the target device 4 is in the heat source demand state, the waste heat obtained by the heat exchange station is directly supplied to the target device 4; when the target device 4 is in the cold source demand state, the waste heat obtained by the heat exchange station can be used as a driving heat source to drive the refrigerator 5, and the cold source produced by the refrigerator 5 is supplied to the target device 4, thereby realizing the full utilization of the waste heat of the blast furnace slag flushing water.

[0043] The blast furnace slag flushing water waste heat utilization system provided by the present invention connects the heat exchange stations connected to the slag outlets in a one-to-one correspondence in series, so that the circulating medium of the target equipment 4 flows through all the heat exchange stations in sequence, so that it can exchange heat with the blast furnace slag flushing water in the heat exchange station corresponding to the current slag outlet when the blast furnace 1 is in a slag discharging state, so that when the slag outlets of the blast furnace 1 are alternately discharging slag, the heat of the slag water can be continuously extracted for waste heat utilization, and at the same time, the influence of the slag water temperature change when the slag outlets of the blast furnace 1 are alternately discharging slag on the target equipment 4 is reduced, and the waste heat utilization rate of the blast furnace slag flushing water is improved.

[0044] According to a preferred embodiment of the present invention, Figure 1 As shown, the blast furnace slag water waste heat utilization system also includes a refrigerator 5, and the refrigerator 5 has a driving heat source inlet, a driving heat source outlet, a target medium inlet and a target medium outlet. The driving heat source inlet is controllably connected to the cold outlet of the heat exchange station at the end of the series connection, and the driving heat source outlet is controllably connected to the cold inlet of the heat exchange station at the head of the series connection. The target medium inlet is controllably connected to the flow outlet, and the target medium outlet is controllably connected to the flow inlet. By setting up the refrigerator 5, and selectively sending the heat extracted from the slag water to the refrigerator 5 as a driving heat source, the driving refrigerator 5 produces a low-temperature target medium, that is, a cold source, after working, so as to supply cold users. In this way, through the selective access of the refrigerator 5, the blast furnace slag water waste heat utilization system provided by the present invention has a cold and heat co-supply function, so as to meet the user's summer cooling use needs and winter heating use needs. Among them, the refrigerator 5 can be one, or it can be set to multiple as needed, and this application does not limit this.

[0045] According to one embodiment of the present invention, the blast furnace 1 has a first slag outlet 11 and a second slag outlet 12, the heat exchange station correspondingly connected to the first slag outlet 11 is the first heat exchange station 2, and the heat exchange station correspondingly connected to the second slag outlet 12 is the second heat exchange station 3, the cold inlet of the first heat exchange station 2 is controllably connected to the flow outlet, the cold inlet of the second heat exchange station 3 is connected to the cold outlet of the first heat exchange station 2, and the cold outlet of the second heat exchange station 3 is controllably connected to the flow inlet; the target medium inlet is controllably connected to the flow outlet, the driving heat source inlet is controllably connected to the cold outlet of the second heat exchange station 3, the driving heat source outlet is controllably connected to the cold inlet of the first heat exchange station 2, and the target medium outlet is controllably connected to the flow inlet.

[0046] Specifically, Figure 1 As shown, the first heat exchange station 2 is arranged near the first slag outlet 11, and the second heat exchange station 3 is arranged near the second slag outlet 12, so as to shorten the circulation process of the slag flushing water as much as possible, so as to achieve the purpose of taking into account the particularity of the slag water properties. In summer, the heat extracted from the slag water by the heat exchange station is sent to the refrigerator 5 as a driving heat source, driving the refrigerator 5 to work and produce a cold source for the user to use for cooling; in winter, the heat extracted from the slag water by the heat exchange station is directly sent to the user for heating.

[0047] According to one embodiment of the present invention, the target device 4 has a cold source demand state and a heat source demand state. In the heat source demand state, the refrigerator 5 is in a closed state, the cold inlet of the first heat exchange station 2 is connected to the outlet, the cold outlet of the second heat exchange station 3 is connected to the inlet, and the heat extracted from the slag water by the heat exchange station is directly sent to the target device 4 for use. In the cold source demand state, the refrigerator 5 is in an open state, the target medium inlet is connected to the outlet, the driving heat source inlet is connected to the cold outlet of the second heat exchange station 3, the driving heat source outlet is connected to the cold inlet of the first heat exchange station 2, the target medium outlet is connected to the inlet, and the heat extracted from the slag water by the heat exchange station is used to drive the refrigerator 5 to work and deliver the cold source to the target device 4 for use.

[0048] Specifically, under the heat source demand state, the target device 4 at the user's location produces heating water return water after heat exchange, and the heating water return water passes through the first heat exchange station 2 and the second heat exchange station 3 in turn to absorb heat, and the heating water return water is heated to form heating water supply, and then sent to the user for heating use, and the heating water return water after heat exchange returns to the first heat exchange station 2, thereby completing a heat source cycle. Under the cold source demand state, the driving heat source water return water on the hot side of the refrigerator 5 passes through the first heat exchange station 2 and the second heat exchange station 3 in turn to absorb heat, and the driving heat source water return water is heated to form driving heat source water, and is sent to the refrigerator 5 to drive the refrigerator 5 to work, and the driving heat source water return water after use returns to the first heat exchange station 2, thereby completing a hot side cycle of the refrigerator 5; the chilled water produced by the refrigerator 5 is sent to the target device 4 at the user's location to form chilled water return water after heat exchange, and the chilled water return water is sent back to the refrigerator 5, thereby completing a cold side cycle of the refrigerator 5. That is, the driving heat source water is used as an intermediate medium between the heat exchange station and the refrigerator 5 , bringing the heat of the slag water obtained by the heat exchange station to the refrigerator 5 and finally converting it into application in the target device 4 .

[0049] According to one embodiment of the present invention, Figure 1 As shown, an outflow pipe 10 is connected between the cold inlet and the outflow outlet of the first heat exchange station 2, an inflow pipe 20 is connected between the cold outlet and the inflow of the second heat exchange station 3, the target medium inlet is connected to the outflow pipe 10 through the outflow branch pipe 30, the driving heat source inlet is connected to the cold outlet of the second heat exchange station 3 through the first connecting pipe 40, the driving heat source outlet is connected to the outflow pipe 10 through the second connecting pipe 50, and the target medium outlet is connected to the inflow pipe 20 through the inflow branch pipe 60; a first cutting mechanism K1 is provided on the outflow pipe 10 between the outflow branch pipe 30 and the second connecting pipe 50, a second cutting mechanism K2 is provided on the inflow pipe 20 between the inflow branch pipe 60 and the cold outlet of the second heat exchange station 3, a third cutting mechanism K3 is provided on the first connecting pipe 40, a fourth cutting mechanism K4 is provided on the second connecting pipe 50, a fifth cutting mechanism K5 is provided on the outflow branch pipe 30, and a sixth cutting mechanism K6 is provided on the inflow branch pipe 60. By setting a cut-off mechanism on the corresponding pipeline, the switching control of the cooling output and the heating output of the blast furnace slag water waste heat utilization system is realized. And by leading the inflow branch pipe 60 from the inflow pipe 20 to connect the target medium outlet, and leading the outflow branch pipe 30 from the outflow pipe 10 to connect the target medium inlet, the system optimization and investment saving are realized.

[0050] According to one embodiment of the present invention, the first cut-off mechanism K1, the second cut-off mechanism K2, the third cut-off mechanism K3, the fourth cut-off mechanism K4, the fifth cut-off mechanism K5, and the sixth cut-off mechanism K6 are all manual switch valves. When the target device 4 is in a cold source demand state, the first cut-off mechanism K1 and the second cut-off mechanism K2 are in an open state, and the third cut-off mechanism K3, the fourth cut-off mechanism K4, the fifth cut-off mechanism K5, and the sixth cut-off mechanism K6 are in a closed state; when the target device 4 is in a heat source demand state, the first cut-off mechanism K1 and the second cut-off mechanism K2 are in a closed state, and the third cut-off mechanism K3, the fourth cut-off mechanism K4, the fifth cut-off mechanism K5, and the sixth cut-off mechanism K6 are in an open state. By setting the first cut-off mechanism K1, the second cut-off mechanism K2, the third cut-off mechanism K3, the fourth cut-off mechanism K4, the fifth cut-off mechanism K5, and the sixth cut-off mechanism K6 as manual switch valves, the switching control requirements of summer cooling output and winter heating output can be taken into account on the basis of saving costs and energy consumption.

[0051] According to one embodiment of the present invention, the first cut-off mechanism K1, the second cut-off mechanism K2, the third cut-off mechanism K3, the fourth cut-off mechanism K4, the fifth cut-off mechanism K5, and the sixth cut-off mechanism K6 are all electric switch valves. After obtaining the cold source demand state signal of the target device 4, the first cut-off mechanism K1 and the second cut-off mechanism K2 enter the disconnected state, and the third cut-off mechanism K3, the fourth cut-off mechanism K4, the fifth cut-off mechanism K5, and the sixth cut-off mechanism K6 enter the closed state; after obtaining the heat source demand state signal of the target device 4, the first cut-off mechanism K1 and the second cut-off mechanism K2 enter the closed state, and the third cut-off mechanism K3, the fourth cut-off mechanism K4, the fifth cut-off mechanism K5, and the sixth cut-off mechanism K6 enter the disconnected state. In this way, the real-time fast switching control response of the cooling output and the heating output can be realized according to the use demand of the target device 4.

[0052] According to one embodiment of the present invention, the outer walls of the outflow pipe 10, the inflow pipe 20, the outflow branch pipe 30, the inflow branch pipe 60, the first connecting pipe 40, and the second connecting pipe 50 are all provided with a fire-resistant heat-insulating material layer. By providing the fire-resistant heat-insulating material layer outside the connecting pipe, the heat exchange between the medium in the pipe and the external environment is reduced, and the utilization efficiency of the waste heat of the slag water is further improved.

[0053] According to one embodiment of the present invention, the fire-resistant heat-insulating material layer is a fire-resistant heat-insulating coating coated on the outer wall of the pipeline.

[0054] According to one embodiment of the present invention, the fire-resistant heat-insulating material layer is fire-resistant heat-insulating wool coated on the outer wall of the pipeline.

[0055] The present invention also provides a control method applied to the above-mentioned blast furnace slag flushing water waste heat utilization system, comprising: obtaining a demand state signal of a target device; sending a corresponding action signal to each electric switch valve based on the demand state signal of the target device; each electric switch valve performs a corresponding action based on the received action signal to enter a closed state or a disconnected state; wherein the demand state signal of the target device includes a heat source demand state signal and a cold source demand state signal, and the action signal includes a closed action signal and an disconnected action signal, and when the demand state signal of the target device is a cold source demand state signal, a disconnected action signal is sent to the first cut-off mechanism and the second cut-off mechanism, and a closed action signal is sent to the third cut-off mechanism, the fourth cut-off mechanism, the fifth cut-off mechanism, and the sixth cut-off mechanism; when the demand state signal of the target device is a heat source demand state signal, a closed action signal is sent to the first cut-off mechanism and the second cut-off mechanism, and a disconnected action signal is sent to the third cut-off mechanism, the fourth cut-off mechanism, the fifth cut-off mechanism, and the sixth cut-off mechanism.

[0056] Specifically, the blast furnace slag flushing water waste heat utilization system also includes a controller, which is electrically connected to the target device and each electric switch valve. The controller receives a demand status signal of the target device, and sends a corresponding action signal to each electric switch valve, so that each electric switch valve performs a corresponding action, thereby realizing closed-loop control of cooling output and heating output based on the usage requirements of the target device 4, which not only improves the waste heat utilization rate of the slag flushing water, but also meets the needs of the target device.

[0057] Based on the above description, the blast furnace slag washing water waste heat utilization system provided by the embodiment of the present invention has the following beneficial effects:

[0058] The blast furnace slag flushing water waste heat utilization system provided in the embodiment of the present invention connects the heat exchange stations connected with the slag outlets in series in a one-to-one manner, so that when the slag outlets of the blast furnace 1 are alternately discharged, the heat of the slag water can be continuously extracted for waste heat utilization, while reducing the impact of the slag water temperature change on the target equipment 4 when the slag outlets of the blast furnace 1 are alternately discharged, and the waste heat utilization rate of the blast furnace slag flushing water is improved; at the same time, through the selective connection of the refrigerator 5, the blast furnace slag flushing water waste heat utilization system provided by the present invention has the function of combined cold and hot supply, thereby being able to meet the user's summer cooling use needs and winter heating use needs.

[0059] The above are only several embodiments of the present invention. Those skilled in the art may make various changes or modifications to the embodiments of the present invention based on the contents disclosed in the application documents without departing from the spirit and scope of the present invention.

Claims

1. A blast furnace slag flushing water waste heat utilization system, characterized in that: include: a target device having a flow inlet and a flow outlet; A blast furnace having at least two slag tapping openings; A plurality of heat exchange stations are connected one-to-one with at least two of the slag outlets, the heat exchange stations having a hot inlet, a hot outlet, a cold inlet and a cold outlet, the hot inlet and the hot outlet are connected to the slag outlet, and the plurality of heat exchange stations are connected in series through the cold inlet and the cold outlet, the cold inlet of the heat exchange station located at the head end of the series connection is controllably connected to the outflow outlet, and the cold outlet of the heat exchange station located at the end of the series connection is controllably connected to the inflow inlet.

2. The blast furnace slag flushing water waste heat utilization system according to claim 1, characterized in that: The blast furnace slag flushing water waste heat utilization system also includes a refrigerator, which has a driving heat source inlet, a driving heat source outlet, a target medium inlet and a target medium outlet. The driving heat source inlet is controllably connected to the cold outlet of the heat exchange station located at the end of the series connection, and the driving heat source outlet is controllably connected to the cold inlet of the heat exchange station located at the head end of the series connection. The target medium inlet is controllably connected to the outflow outlet, and the target medium outlet is controllably connected to the inflow inlet.

3. The blast furnace slag flushing water waste heat utilization system according to claim 2 is characterized in that: The blast furnace has a first slag outlet and a second slag outlet. The heat exchange station corresponding to the first slag outlet is the first heat exchange station, and the heat exchange station corresponding to the second slag outlet is the second heat exchange station. The cold inlet of the first heat exchange station is controllably connected to the outflow outlet, the cold inlet of the second heat exchange station is connected to the cold outlet of the first heat exchange station, and the cold outlet of the second heat exchange station is controllably connected to the inflow inlet; the target medium inlet is controllably connected to the outflow outlet, the driving heat source inlet is controllably connected to the cold outlet of the second heat exchange station, the driving heat source outlet is controllably connected to the cold inlet of the first heat exchange station, and the target medium outlet is controllably connected to the inflow inlet.

4. The blast furnace slag flushing water waste heat utilization system according to claim 3 is characterized in that: The target device has a cold source demand state and a heat source demand state. In the heat source demand state, the refrigerator is in a closed state, the cold inlet of the first heat exchange station is connected to the outflow outlet, and the cold outlet of the second heat exchange station is connected to the inflow inlet; in the cold source demand state, the refrigerator is in an open state, the target medium inlet is connected to the outflow outlet, the driving heat source inlet is connected to the cold outlet of the second heat exchange station, the driving heat source outlet is connected to the cold inlet of the first heat exchange station, and the target medium outlet is connected to the inflow inlet.

5. The blast furnace slag flushing water waste heat utilization system according to claim 4 is characterized in that: An outflow pipe is connected between the cold inlet and the outflow outlet of the first heat exchange station, an inflow pipe is connected between the cold outlet and the inflow of the second heat exchange station, the target medium inlet is connected to the outflow pipe through an outflow branch pipe, the driving heat source inlet is connected to the cold outlet of the second heat exchange station through a first connecting pipe, the driving heat source outlet is connected to the outflow pipe through a second connecting pipe, and the target medium outlet is connected to the inflow pipe through an inflow branch pipe; a first cutting mechanism is provided on the outflow pipe between the outflow branch pipe and the second connecting pipe, a second cutting mechanism is provided on the inflow pipe between the inflow branch pipe and the cold outlet of the second heat exchange station, a third cutting mechanism is provided on the first connecting pipe, a fourth cutting mechanism is provided on the second connecting pipe, a fifth cutting mechanism is provided on the outflow branch pipe, and a sixth cutting mechanism is provided on the inflow branch pipe.

6. The blast furnace slag flushing water waste heat utilization system according to claim 5, characterized in that: The first cut-off mechanism, the second cut-off mechanism, the third cut-off mechanism, the fourth cut-off mechanism, the fifth cut-off mechanism and the sixth cut-off mechanism are all manual switch valves. When the target device is in a cold source demand state, the first cut-off mechanism and the second cut-off mechanism are in an open state, and the third cut-off mechanism, the fourth cut-off mechanism, the fifth cut-off mechanism and the sixth cut-off mechanism are in a closed state; when the target device is in a hot source demand state, the first cut-off mechanism and the second cut-off mechanism are in a closed state, and the third cut-off mechanism, the fourth cut-off mechanism, the fifth cut-off mechanism and the sixth cut-off mechanism are in an open state.

7. The blast furnace slag flushing water waste heat utilization system according to claim 5, characterized in that: The first cut-off mechanism, the second cut-off mechanism, the third cut-off mechanism, the fourth cut-off mechanism, the fifth cut-off mechanism, and the sixth cut-off mechanism are all electric switch valves. After obtaining the cold source demand state signal of the target device, the first cut-off mechanism and the second cut-off mechanism enter the disconnected state, and the third cut-off mechanism, the fourth cut-off mechanism, the fifth cut-off mechanism, and the sixth cut-off mechanism enter the closed state; after obtaining the hot source demand state signal of the target device, the first cut-off mechanism and the second cut-off mechanism enter the closed state, and the third cut-off mechanism, the fourth cut-off mechanism, the fifth cut-off mechanism, and the sixth cut-off mechanism enter the disconnected state.

8. The blast furnace slag flushing water waste heat utilization system according to claim 5, characterized in that: The outer walls of the outflow pipe, the inflow pipe, the outflow branch pipe, the inflow branch pipe, the first connecting pipe, and the second connecting pipe are all provided with a fire-resistant heat-insulating material layer.

9. The blast furnace slag flushing water waste heat utilization system according to claim 8, characterized in that: The fire-resistant heat-insulating material layer is a fire-resistant heat-insulating coating applied to the outer wall of the pipeline, or the fire-resistant heat-insulating material layer is a fire-resistant heat-insulating cotton coated on the outer wall of the pipeline.

10. The blast furnace slag flushing water waste heat utilization system according to claim 1, characterized in that: The slag flushing water circulates between the slag outlet and the corresponding heat exchange station connected thereto, and exchanges heat between the heat exchange station and the circulating medium of the target equipment; the circulating medium of the target equipment flows through all the heat exchange stations in sequence, and exchanges heat with the slag flushing water in the heat exchange station connected to the slag outlet of the blast furnace that is in a slag discharging state.

11. A control method for the blast furnace slag flushing water waste heat utilization system as claimed in claim 7, characterized in that: include: Acquire a demand status signal of the target device; Based on the demand state signal of the target device, a corresponding action signal is sent to each electric switch valve; Each electric switch valve performs a corresponding action based on the received action signal to enter a closed state or an open state; Wherein, the demand state signal of the target device includes a heat source demand state signal and a cold source demand state signal, and the action signal includes a closing action signal and an opening action signal. When the demand state signal of the target device is a cold source demand state signal, an opening action signal is sent to the first cutting mechanism and the second cutting mechanism, and a closing action signal is sent to the third cutting mechanism, the fourth cutting mechanism, the fifth cutting mechanism, and the sixth cutting mechanism; when the demand state signal of the target device is a heat source demand state signal, a closing action signal is sent to the first cutting mechanism and the second cutting mechanism, and an opening action signal is sent to the third cutting mechanism, the fourth cutting mechanism, the fifth cutting mechanism, and the sixth cutting mechanism.

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