A gas purification and waste heat recovery system for blast furnaces, converters and coke ovens

Abstract

The present invention relates to the technical field of coal gas purification, and in particular to a coal gas purification and waste heat recovery system for blast furnaces, converters and coke ovens, comprising a waste heat recovery device, a purification device, a purification fan, a steam drum device, a gas holder, a venting chimney, a nitrogen delivery device, a cooling water delivery device, a detection device and a delivery analysis module. Whether the coal gas delivery is smooth is determined based on the delivery situation of the clean coal gas, while ensuring the coal gas delivery efficiency and improving the stability of high-temperature coal gas purification. When the temperature of the purification fan is greater than a preset temperature, the temperature of the purification fan is too high. In this case, the purification fan stalls due to overload. The purification fan is cooled according to the specific temperature situation to ensure that the waste heat of the high-temperature coal gas is fully recovered, improve the utilization rate of thermal energy, and further improve the heat exchange efficiency of the high-temperature coal gas.

Description

Technical Field

[0001] The invention relates to the technical field of coal gas purification, and in particular to a coal gas purification and waste heat recovery system for a blast furnace, a converter and a coke oven. Background Art

[0002] As the demand for the steel industry weakens, ferroalloy products, as upstream raw materials of the steel industry, are also affected accordingly. Therefore, increasing production capacity, reducing energy consumption, controlling costs, and strengthening the energy recovery and utilization of high-heat waste gas, waste water, and waste slag are the problems that the ferroalloy industry urgently needs to solve. In the production process of blast furnaces, converters, and coke ovens, gas purification and waste heat recovery play a vital role. By recovering the waste heat of blast furnaces, converters, and coke ovens, energy utilization efficiency can be effectively improved, and it has a positive impact on environmental protection and corporate economic benefits.

[0003] Traditional high-temperature coal gas purification uses three-stage or four-stage air coolers or "cyclone dust removal + settler" and other combined devices to cool down and remove large particles. The high-temperature coal gas from blast furnaces, converters and coke ovens is a recyclable high-calorific value fuel gas. After gas purification, dust removal and cooling, it is sent to the gas tank for storage, and then sent to the user end after pressure equalization and flow stabilization through the gas tank, and can be used in rotary kilns or drying kilns.

[0004] Chinese Patent Publication No.: CN111826210A, discloses a high-temperature dust removal process and device for raw coal gas, in which the dust collector uses semi-coke as the filter medium. After the pyrolysis dust-containing raw coal gas is discharged from the pyrolysis equipment, it is directly connected to the bottom of the fixed bed / granular bed raw coal gas high-temperature dust collector through the raw coal gas pipeline, passes through the filter material from bottom to top, and after filtering the dust in the raw coal gas, the purified raw coal gas is discharged from the upper outlet of the dust collector into the downstream process. During the entire filtering and dust removal process, the pipeline and dust removal equipment are kept at a high temperature to prevent tar precipitation. The semi-coke filter material after filtration and saturation is discharged from the bottom of the dust collector through the discharge device and falls into the coke quenching waste heat recovery device for cooling. The dust removal device consists of three parts: a dust collector body, a semi-coke preheater, and a discharge lock bucket. It can be seen that the prior art has the following problems: it does not take into account the flow rate of each water channel or the delivery rate of nitrogen delivered to each bag bin according to the flow rate of the obtained clean coal gas and the temperature of the purification fan, which affects the utilization rate of the high-temperature coal gas and further affects the heat exchange efficiency of the high-temperature coal gas. Summary of the invention

[0005] To this end, the present invention provides a gas purification and waste heat recovery system for blast furnaces, converters and coke ovens, so as to overcome the problem that the prior art does not take into account the flow rate of each water channel or the delivery flow rate of nitrogen delivered to each bag bin according to the flow rate of the obtained clean gas and the temperature of the purification fan, which affects the utilization rate of the high-temperature gas and further affects the heat exchange efficiency of the high-temperature gas.

[0006] To achieve the above object, the present invention provides a gas purification and waste heat recovery system for blast furnaces, converters and coke ovens, comprising:

[0007] A waste heat recovery device, which is used to cool the input high-temperature coal gas, including an ash hopper for depositing ash in the raw coal gas, an economizer for heating the input cold water, and a plurality of evaporators for heating the input cold water into a steam-water mixture;

[0008] The purification device comprises a plurality of bag bins arranged at the output end of the ash hopper for filtering and purifying the raw gas and a plurality of buffer bins respectively connected to the corresponding bag bins for collecting ash;

[0009] Purification fans are connected to each bag bin to transport clean gas filtered by the bag bin;

[0010] a drum device, which is connected to the economizer and each evaporator, respectively, for receiving the steam-water mixture output by each evaporator and the hot water output by the economizer, and outputting the received hot water to each evaporator for further evaporation, and the drum device outputs the received water vapor;

[0011] A gas cabinet connected to the output end of the purification fan for receiving and using purified gas;

[0012] A discharge chimney connected to the output end of the purification fan for emergency discharge of unusable clean gas in the gas tank;

[0013] A nitrogen delivery device, which is respectively connected to the ash hopper, the venting chimney, and each bag bin, for delivering nitrogen to the ash hopper to replace the high-temperature coal gas during maintenance, for cleaning each bag bin by delivering nitrogen to the bag bin, and for extinguishing fire by delivering nitrogen to the venting chimney;

[0014] A cooling water delivery device, comprising a first water path connected to the purification fan for cooling the purification fan and a second water path connected to the economizer for supplying water to the economizer;

[0015] A detection device, comprising a flow meter arranged at the output end of the purification fan for obtaining the flow rate of the clean coal gas and a temperature detector located at one side of the purification fan;

[0016] The transport analysis module is respectively connected to the waste heat recovery device, the purification device, the purification fan, the emission chimney, the nitrogen transport device, the cooling water transport device and the detection device, and is used to determine the flow rate of the first water channel, the flow rate of the second water channel, or the transport flow rate of the nitrogen transported to each bag bin to be adjusted to a corresponding value according to the acquired flow rate of the clean coal gas and the temperature of the purification fan.

[0017] Furthermore, the transport analysis module determines whether the operation status of the waste heat recovery device meets the preset standard according to the acquired flow rate of the clean coal gas, wherein:

[0018] If the flow rate is greater than the third preset flow rate, the transport analysis module determines that the operation status of the waste heat recovery device does not meet the preset standard, and controls the purification fan to transport the clean coal gas to the vent chimney for emergency discharge;

[0019] If the flow rate is less than or equal to the third preset flow rate and greater than the second preset flow rate, the transport analysis module determines that the operation status of the waste heat recovery device meets the preset standard, and controls the waste heat recovery device to continue to operate using the current operation parameters;

[0020] If the flow rate is less than or equal to the second preset flow rate and greater than the first preset flow rate, the transport analysis module re-determines whether the operating condition of the waste heat recovery device meets the preset standard according to the obtained temperature of the purification fan;

[0021] If the flow rate is less than or equal to the first preset flow rate, the transport analysis module determines that the operation status of the waste heat recovery device does not meet the preset standard, and determines the treatment method for the operation status of the waste heat recovery device not meeting the preset standard according to the historical flow rate of the clean coal gas;

[0022] Furthermore, the transport analysis module re-determines whether the operating status of the waste heat recovery device meets the preset standard according to the acquired temperature of the purification fan, wherein:

[0023] If the temperature is greater than the preset temperature, the transport analysis module determines a treatment method for the purification fan according to the difference between the temperature and the preset temperature;

[0024] If the temperature is less than or equal to the preset temperature, the transport analysis module determines, based on the historical flow rate of the clean coal gas, a treatment method for the operating condition of the waste heat recovery device not meeting the preset standard.

[0025] Furthermore, the transport analysis module records the difference between the temperature and the preset temperature as the temperature difference, and determines a processing method for the purification fan according to the temperature difference, wherein:

[0026] If the temperature difference is less than or equal to the preset temperature difference, the transport analysis module adjusts the flow rate of the first water channel to a corresponding value according to the difference between the preset temperature difference and the temperature difference;

[0027] If the temperature difference is greater than the preset temperature difference, the transport analysis module adjusts the flow rate of the second water channel to a corresponding value according to the difference between the temperature difference and the preset temperature difference.

[0028] Furthermore, the transport analysis module records the difference between the preset temperature difference and the temperature difference as the fan difference, and the analysis module determines the fan adjustment method for the flow rate of the first water channel according to the fan difference, wherein:

[0029] If the fan difference is less than or equal to the first preset fan difference, the transport analysis module uses the first preset fan adjustment coefficient to adjust the flow rate of the first waterway to a corresponding value;

[0030] If the fan difference is less than or equal to the second preset fan difference and greater than the first preset fan difference, the transport analysis module uses the second preset fan adjustment coefficient to adjust the flow rate of the first waterway to a corresponding value;

[0031] If the fan difference is greater than the second preset fan difference, the transport analysis module uses the third preset fan adjustment coefficient to adjust the flow rate of the first water channel to a corresponding value; the second preset fan difference is greater than the first preset fan difference.

[0032] Furthermore, the transport analysis module records the difference between the temperature difference and the preset temperature difference as the coal saving difference, and the analysis module determines the coal saving adjustment method for the flow rate of the second waterway according to the coal saving difference, wherein:

[0033] If the coal saving difference is less than or equal to the first preset coal saving difference, the transport analysis module uses the first preset coal saving adjustment coefficient to adjust the flow rate of the second waterway to a corresponding value;

[0034] If the coal saving difference is less than or equal to the second preset coal saving difference and greater than the first preset coal saving difference, the transport analysis module uses the second preset coal saving adjustment coefficient to adjust the flow rate of the second waterway to a corresponding value;

[0035] If the coal saving difference is greater than the second preset coal saving difference, the transportation analysis module uses the third preset coal saving adjustment coefficient to adjust the flow rate of the second waterway to a corresponding value; the second preset coal saving difference is greater than the first preset coal saving difference.

[0036] Furthermore, the transport analysis module draws a time-flow curve according to the historical flow rate of the clean coal gas, and determines a treatment method for the operation status of the waste heat recovery device not meeting the preset standard according to the calculated curve slope of the time-flow curve at the current time node, wherein:

[0037] If the slope of the curve is greater than a preset slope, the delivery analysis module adjusts the delivery flow rate of the nitrogen to a corresponding value according to the difference between the second preset flow rate and the flow rate;

[0038] If the slope of the curve is less than or equal to the preset slope, the transport analysis module reduces the operating power of the purification fan to a corresponding value according to the difference between the preset slope of the curve and the slope of the curve.

[0039] Further, the delivery analysis module records the difference between the second preset flow rate and the flow rate as the delivery difference, and determines a delivery adjustment method for the delivery flow rate of nitrogen according to the delivery difference, wherein:

[0040] If the delivery difference is less than or equal to the first preset delivery difference, the delivery analysis module uses the first preset delivery adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value;

[0041] If the delivery difference is less than or equal to the second preset delivery difference and greater than the first preset delivery difference, the delivery analysis module uses the second preset delivery adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value;

[0042] If the delivery difference is greater than the second preset delivery difference, the delivery analysis module uses a third preset delivery adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value; the second preset delivery difference is greater than the first preset delivery difference.

[0043] Furthermore, the transport analysis module records the difference between the preset curve slope and the curve slope as the curve difference, and determines the curve adjustment method for the operating power of the purification fan according to the curve difference, wherein:

[0044] If the curve difference is less than or equal to the first preset curve difference, the delivery analysis module uses the first preset curve adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value;

[0045] If the curve difference is less than or equal to the second preset curve difference and greater than the first preset curve difference, the delivery analysis module uses the second preset curve adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value;

[0046] If the curve difference is greater than the second preset curve difference, the delivery analysis module uses the third preset curve adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value; the second preset curve difference is greater than the first preset curve difference.

[0047] Furthermore, the buffer bin is connected to the ash hopper to collect and store ash in the ash hopper;

[0048] The nitrogen delivery device is also connected to each of the buffer bins, respectively, to maintain a positive pressure in the bin body when the buffer bin is unloading ash.

[0049] Compared with the prior art, the beneficial effect of the present invention is that whether the gas delivery is smooth is determined based on the delivery condition of the clean gas. While ensuring the gas delivery efficiency, the stability of high-temperature gas purification is improved, and the heat exchange efficiency of high-temperature gas is further improved.

[0050] Further, when the flow rate is less than or equal to the second preset flow rate and greater than the first preset flow rate, it is re-determined whether the operating condition of the waste heat recovery device meets the preset standard according to the temperature of the purification fan. When the temperature is greater than the preset temperature, the temperature of the purification fan is too high. In this case, the purification fan stalls due to overload. The purification fan is cooled down according to the specific temperature conditions. When the temperature difference is less than or equal to the preset temperature difference, the temperature is only slightly higher. In this case, the temperature is high due to problems with the purification fan itself. At this time, the flow rate of the first water path used to cool the purification fan is increased to cool the purification fan; when the temperature difference is greater than the preset temperature difference, the temperature is too high. In this case, because the flow rate of the second water path used to supply water to the economizer is too slow, the cooling of the high-temperature coal gas is insufficient, so that there are problems in heat exchange, causing the temperature of the purification fan to be too high. At this time, the flow rate of the second water path is increased to ensure that the waste heat of the high-temperature coal gas is fully recovered and the utilization rate of thermal energy is improved, thereby improving the heat exchange efficiency of the high-temperature coal gas.

[0051] Furthermore, a specific treatment method is determined based on changes in historical flow rates. When the slope of the curve is less than or equal to a preset slope, the flow rate changes dramatically. In this case, the sealing of the waste heat recovery device is reduced due to too little ash accumulation in the ash hopper, resulting in increased energy losses inside the waste heat recovery device, and the high-temperature coal gas is not fully utilized, thereby reducing the flow rate of the clean coal gas. In this case, the operating power of the purification fan is lowered to a corresponding value to reduce the air flow velocity inside the system, reduce the suspended concentration of ash in the air flow, and weaken the air flow's carrying capacity for ash, thereby effectively adhering to the side wall of the ash hopper to improve the sealing of the waste heat recovery device, while effectively increasing the utilization rate of the high-temperature coal gas and further improving the heat exchange efficiency for the high-temperature coal gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 This is a module block diagram of a gas purification and waste heat recovery system for a blast furnace, a converter and a coke oven according to an embodiment of the present invention;

[0053] Figure 2 This is a schematic structural diagram of a waste heat recovery device according to an embodiment of the present invention;

[0054] Figure 3 It is a structural schematic diagram of a steam drum device according to an embodiment of the present invention;

[0055] Includes: 1. Evaporator; 2. Economizer. DETAILED DESCRIPTION

[0056] In order to make the objects and advantages of the present invention more clearly understood, the present invention is further described below in conjunction with embodiments; it should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0057] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the protection scope of the present invention.

[0058] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "inside" and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is merely for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0059] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, 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 indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0060] See also Figure 1 , Figure 2 ,as well as Figure 3 As shown, they are respectively a module block diagram of a gas purification and waste heat recovery system for a blast furnace, a converter and a coke oven according to an embodiment of the present invention, a structural schematic diagram of a waste heat recovery device, a structural schematic diagram of a drum device, and a flow chart of a transport analysis module determining whether the operating status of the waste heat recovery device meets a preset standard according to the flow rate of the clean gas; a gas purification and waste heat recovery system for a blast furnace, a converter and a coke oven according to an embodiment of the present invention, comprising:

[0061] A waste heat recovery device, which is used to cool the input high-temperature coal gas, includes an ash hopper for depositing ash in the raw coal gas, an economizer 2 for heating the input cold water, and a plurality of evaporators 1 for heating the input cold water into a steam-water mixture;

[0062] The purification device comprises a plurality of bag bins arranged at the output end of the ash hopper for filtering and purifying the raw gas and a plurality of buffer bins respectively connected to the corresponding bag bins for collecting ash;

[0063] Purification fans are connected to each bag bin to transport clean gas filtered by the bag bin;

[0064] a drum device, which is connected to the economizer 2 and each evaporator 1, respectively, for receiving the steam-water mixture output by each evaporator 1 and the hot water output by the economizer 2, and outputting the received hot water to each evaporator 1 for further evaporation, and the drum device outputs the received water vapor;

[0065] A gas cabinet connected to the output end of the purification fan for receiving and using purified gas;

[0066] A discharge chimney connected to the output end of the purification fan for emergency discharge of unusable clean gas in the gas tank;

[0067] A nitrogen delivery device, which is respectively connected to the ash hopper, the venting chimney, and each bag bin, for delivering nitrogen to the ash hopper to replace the high-temperature coal gas during maintenance, for cleaning each bag bin by delivering nitrogen to the bag bin, and for extinguishing fire by delivering nitrogen to the venting chimney;

[0068] A cooling water delivery device, comprising a first water path connected to the purification fan for cooling the purification fan and a second water path connected to the economizer 2 for supplying water to the economizer 2;

[0069] A detection device, comprising a flow meter arranged at the output end of the purification fan for obtaining the flow rate of the clean coal gas and a temperature detector located at one side of the purification fan for obtaining the temperature of the purification fan;

[0070] The transport analysis module is respectively connected to the waste heat recovery device, the purification device, the purification fan, the emission chimney, the nitrogen transport device, the cooling water transport device and the detection device, and is used to determine the flow rate of the first water channel, the flow rate of the second water channel, or the transport flow rate of the nitrogen transported to each bag bin to be adjusted to a corresponding value according to the acquired flow rate of the clean coal gas and the temperature of the purification fan.

[0071] Specifically, the high-temperature coal gas of the exhaust gas generated by the closed blast furnace, converter and coke oven is connected to the waste heat recovery device, and the second water path sends cold water to the waste heat recovery device;

[0072] Preferably, the evaporator 1 adopts a Φ32×3 serpentine tube with tube bundles arranged in series. The inner diameter of the steam drum device is φ1200mm. Both ends of the steam drum device are stamped ellipsoidal heads made of Q345R. A pressure gauge, safety valve and emergency exhaust are installed on the top of the steam drum device.

[0073] Specifically, the process of cleaning each bag bin by delivering nitrogen to each bag bin is to generate an impact effect through the injected airflow, so that the bag generates a pulse vibration, and the dust is shaken off and falls into the buffer bin.

[0074] Specifically, the transport analysis module determines whether the operation status of the waste heat recovery device meets the preset standard according to the flow rate of the acquired clean coal gas, wherein:

[0075] If the flow rate is greater than the third preset flow rate, the transport analysis module determines that the operation status of the waste heat recovery device does not meet the preset standard, and controls the purification fan to transport the clean coal gas to the vent chimney for emergency discharge;

[0076] If the flow rate is less than or equal to the third preset flow rate and greater than the second preset flow rate, the transport analysis module determines that the operation status of the waste heat recovery device meets the preset standard, and controls the waste heat recovery device to continue to operate using the current operation parameters;

[0077] If the flow rate is less than or equal to the second preset flow rate and greater than the first preset flow rate, the transport analysis module re-determines whether the operating condition of the waste heat recovery device meets the preset standard according to the obtained temperature of the purification fan;

[0078] If the flow rate is less than or equal to the first preset flow rate, the transport analysis module determines that the operation status of the waste heat recovery device does not meet the preset standard, and determines the treatment method for the operation status of the waste heat recovery device not meeting the preset standard according to the historical flow rate of the clean coal gas;

[0079] Whether the gas delivery is smooth is determined based on the delivery conditions of the clean gas. While ensuring the gas delivery efficiency, the stability of high-temperature gas purification is improved, and the heat exchange efficiency of high-temperature gas is further improved.

[0080] Specifically, the transport analysis module re-determines whether the operating status of the waste heat recovery device meets the preset standard according to the acquired temperature of the purification fan, wherein:

[0081] If the temperature is greater than the preset temperature, the transport analysis module determines a treatment method for the purification fan according to the difference between the temperature and the preset temperature;

[0082] If the temperature is less than or equal to the preset temperature, the transport analysis module determines, based on the historical flow rate of the clean coal gas, a treatment method for the operating condition of the waste heat recovery device not meeting the preset standard.

[0083] Specifically, the transport analysis module records the difference between the temperature and the preset temperature as the temperature difference, and determines the processing method for the purification fan according to the temperature difference, wherein:

[0084] If the temperature difference is less than or equal to the preset temperature difference, the transport analysis module adjusts the flow rate of the first water channel to a corresponding value according to the difference between the preset temperature difference and the temperature difference;

[0085] If the temperature difference is greater than the preset temperature difference, the transport analysis module adjusts the flow rate of the second water channel to a corresponding value according to the difference between the temperature difference and the preset temperature difference.

[0086] When the flow rate is less than or equal to the second preset flow rate and greater than the first preset flow rate, it is determined whether the operating condition of the waste heat recovery device meets the preset standard according to the temperature of the purification fan. When the temperature is greater than the preset temperature, the temperature of the purification fan is too high. In this case, the purification fan stalls due to overload. The purification fan is cooled down according to the specific temperature conditions. When the temperature difference is less than or equal to the preset temperature difference, the temperature is only slightly higher. In this case, the temperature is high due to problems with the purification fan itself. At this time, the flow rate of the first water channel used to cool the purification fan is increased to cool the purification fan; when the temperature difference is greater than the preset temperature difference, the temperature is too high. In this case, because the flow rate of the second water channel used to supply water to the economizer 2 is too slow, the cooling of the high-temperature coal gas is insufficient, so that there are problems in heat exchange, causing the temperature of the purification fan to be too high. At this time, the flow rate of the second water channel is increased to ensure that the waste heat of the high-temperature coal gas is fully recovered and the utilization rate of thermal energy is improved, thereby improving the heat exchange efficiency of the high-temperature coal gas.

[0087] Specifically, the transport analysis module records the difference between the preset temperature difference and the temperature difference as the fan difference, and the analysis module determines the fan adjustment method for the flow rate of the first water channel according to the fan difference, wherein:

[0088] If the fan difference is less than or equal to the first preset fan difference, the transport analysis module uses the first preset fan adjustment coefficient to adjust the flow rate of the first waterway to a corresponding value;

[0089] If the fan difference is less than or equal to the second preset fan difference and greater than the first preset fan difference, the transport analysis module uses the second preset fan adjustment coefficient to adjust the flow rate of the first waterway to a corresponding value;

[0090] If the fan difference is greater than the second preset fan difference, the transport analysis module uses the third preset fan adjustment coefficient to adjust the flow rate of the first water channel to a corresponding value; the second preset fan difference is greater than the first preset fan difference.

[0091] Specifically, the transport analysis module records the difference between the temperature difference and the preset temperature difference as the coal saving difference, and the analysis module determines the coal saving adjustment method for the flow rate of the second waterway according to the coal saving difference, wherein:

[0092] If the coal saving difference is less than or equal to the first preset coal saving difference, the transport analysis module uses the first preset coal saving adjustment coefficient to adjust the flow rate of the second waterway to a corresponding value;

[0093] If the coal saving difference is less than or equal to the second preset coal saving difference and greater than the first preset coal saving difference, the transport analysis module uses the second preset coal saving adjustment coefficient to adjust the flow rate of the second waterway to a corresponding value;

[0094] If the coal saving difference is greater than the second preset coal saving difference, the transportation analysis module uses the third preset coal saving adjustment coefficient to adjust the flow rate of the second waterway to a corresponding value; the second preset coal saving difference is greater than the first preset coal saving difference.

[0095] Specifically, the transport analysis module draws a time-flow curve according to the historical flow rate of the clean coal gas, and determines a treatment method for the operation status of the waste heat recovery device not meeting the preset standard according to the calculated curve slope of the time-flow curve at the current time node, wherein:

[0096] If the slope of the curve is greater than a preset slope, the delivery analysis module adjusts the delivery flow rate of the nitrogen to a corresponding value according to the difference between the second preset flow rate and the flow rate;

[0097] If the slope of the curve is less than or equal to the preset slope, the transport analysis module reduces the operating power of the purification fan to a corresponding value according to the difference between the preset slope of the curve and the slope of the curve.

[0098] The specific treatment method is determined based on the changes in historical flow rates. When the slope of the curve is less than or equal to the preset slope, the flow rate changes dramatically. In this case, the sealing of the waste heat recovery device is reduced due to too little ash accumulation in the ash hopper, resulting in increased energy losses inside the waste heat recovery device, and the high-temperature coal gas cannot be fully utilized, thereby reducing the flow rate of the clean coal gas. In this case, the operating power of the purification fan is lowered to the corresponding value to reduce the air flow speed inside the system, reduce the suspended concentration of ash in the air flow, and weaken the air flow's carrying capacity for ash, thereby effectively attaching the ash to the side wall of the ash hopper to improve the sealing of the waste heat recovery device. While effectively increasing the utilization rate of the high-temperature coal gas, the heat exchange efficiency for the high-temperature coal gas is further improved.

[0099] Specifically, the delivery analysis module records the difference between the second preset flow rate and the flow rate as the delivery difference, and determines the delivery adjustment method for the delivery flow rate of nitrogen according to the delivery difference, wherein:

[0100] If the delivery difference is less than or equal to the first preset delivery difference, the delivery analysis module uses the first preset delivery adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value;

[0101] If the delivery difference is less than or equal to the second preset delivery difference and greater than the first preset delivery difference, the delivery analysis module uses the second preset delivery adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value;

[0102] If the delivery difference is greater than the second preset delivery difference, the delivery analysis module uses a third preset delivery adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value; the second preset delivery difference is greater than the first preset delivery difference.

[0103] Specifically, the transport analysis module records the difference between the preset curve slope and the curve slope as the curve difference, and determines the curve adjustment method for the operating power of the purification fan according to the curve difference, wherein:

[0104] If the curve difference is less than or equal to the first preset curve difference, the delivery analysis module uses the first preset curve adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value;

[0105] If the curve difference is less than or equal to the second preset curve difference and greater than the first preset curve difference, the delivery analysis module uses the second preset curve adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value;

[0106] If the curve difference is greater than the second preset curve difference, the delivery analysis module uses the third preset curve adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value; the second preset curve difference is greater than the first preset curve difference.

[0107] Specifically, the buffer bin is connected to the ash hopper to collect and store ash in the ash hopper;

[0108] The nitrogen delivery device is also connected to each of the buffer bins, respectively, to maintain a positive pressure in the bin body when the buffer bin is unloading ash.

[0109] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

[0110] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A gas purification and waste heat recovery system for blast furnaces, converters and coke ovens, characterized in that: include: A waste heat recovery device, which is used to cool the input high-temperature coal gas, including an ash hopper for depositing ash in the raw coal gas, an economizer for heating the input cold water, and a plurality of evaporators for heating the input cold water into a steam-water mixture; The purification device comprises a plurality of bag bins arranged at the output end of the ash hopper for filtering and purifying the raw gas and a plurality of buffer bins respectively connected to the corresponding bag bins for collecting ash; Purification fans are connected to each bag bin to transport clean gas filtered by the bag bin; a drum device, which is connected to the economizer and each evaporator, respectively, for receiving the steam-water mixture output by each evaporator and the hot water output by the economizer, and outputting the received hot water to each evaporator for further evaporation, and the drum device outputs the received water vapor; A gas cabinet connected to the output end of the purification fan for receiving and using purified gas; A discharge chimney connected to the output end of the purification fan for emergency discharge of unusable clean gas in the gas tank; A nitrogen delivery device, which is respectively connected to the ash hopper, the venting chimney, and each bag bin, for delivering nitrogen to the ash hopper to replace the high-temperature coal gas during maintenance, for cleaning each bag bin by delivering nitrogen to the bag bin, and for extinguishing fire by delivering nitrogen to the venting chimney; A cooling water delivery device, comprising a first water path connected to the purification fan for cooling the purification fan and a second water path connected to the economizer for supplying water to the economizer; A detection device, comprising a flow meter arranged at the output end of the purification fan for obtaining the flow rate of the clean coal gas and a temperature detector located at one side of the purification fan; A transport analysis module, which is respectively connected to the waste heat recovery device, the purification device, the purification fan, the emission chimney, the nitrogen delivery device, the cooling water delivery device and the detection device, and is used to determine the flow rate of the first water channel, the flow rate of the second water channel, or the delivery flow rate of the nitrogen delivered to each bag bin to be adjusted to a corresponding value according to the acquired flow rate of the clean coal gas and the temperature of the purification fan; The transport analysis module determines whether the operation status of the waste heat recovery device meets the preset standard according to the flow rate of the obtained clean coal gas, wherein: If the flow rate is greater than the third preset flow rate, the transport analysis module determines that the operation status of the waste heat recovery device does not meet the preset standard, and controls the purification fan to transport the clean coal gas to the vent chimney for emergency discharge; If the flow rate is less than or equal to the third preset flow rate and greater than the second preset flow rate, the transport analysis module determines that the operation status of the waste heat recovery device meets the preset standard, and controls the waste heat recovery device to continue to operate using the current operation parameters; If the flow rate is less than or equal to the second preset flow rate and greater than the first preset flow rate, the transport analysis module re-determines whether the operating condition of the waste heat recovery device meets the preset standard according to the obtained temperature of the purification fan; If the flow rate is less than or equal to the first preset flow rate, the transport analysis module determines that the operation status of the waste heat recovery device does not meet the preset standard, and determines the treatment method for the operation status of the waste heat recovery device not meeting the preset standard according to the historical flow rate of the clean coal gas; The transport analysis module re-determines whether the operating status of the waste heat recovery device meets the preset standard based on the acquired temperature of the purification fan, wherein: If the temperature is greater than the preset temperature, the transport analysis module determines a treatment method for the purification fan according to the difference between the temperature and the preset temperature; If the temperature is less than or equal to the preset temperature, the transport analysis module determines, based on the historical flow rate of the clean coal gas, a treatment method for the operating condition of the waste heat recovery device that does not meet the preset standard; The transport analysis module records the difference between the temperature and the preset temperature as the temperature difference, and determines a treatment method for the purification fan according to the temperature difference, wherein: If the temperature difference is less than or equal to the preset temperature difference, the transport analysis module adjusts the flow rate of the first water channel to a corresponding value according to the difference between the preset temperature difference and the temperature difference; If the temperature difference is greater than the preset temperature difference, the transport analysis module adjusts the flow rate of the second water channel to a corresponding value according to the difference between the temperature difference and the preset temperature difference; The transport analysis module draws a time-flow curve according to the historical flow rate of the clean coal gas, and determines a treatment method for the operation status of the waste heat recovery device not meeting the preset standard according to the calculated curve slope of the time-flow curve at the current time node, wherein: If the slope of the curve is greater than a preset slope, the delivery analysis module adjusts the delivery flow rate of the nitrogen to a corresponding value according to the difference between the second preset flow rate and the flow rate; If the slope of the curve is less than or equal to the preset slope, the transport analysis module reduces the operating power of the purification fan to a corresponding value according to the difference between the preset slope of the curve and the slope of the curve.

2. The gas purification and waste heat recovery system for blast furnaces, converters and coke ovens according to claim 1, characterized in that: The transport analysis module records the difference between the preset temperature difference and the temperature difference as the fan difference, and the analysis module determines the fan adjustment method for the flow rate of the first water channel according to the fan difference, wherein: If the fan difference is less than or equal to the first preset fan difference, the transport analysis module uses the first preset fan adjustment coefficient to adjust the flow rate of the first waterway to a corresponding value; If the fan difference is less than or equal to the second preset fan difference and greater than the first preset fan difference, the transport analysis module uses the second preset fan adjustment coefficient to adjust the flow rate of the first waterway to a corresponding value; If the fan difference is greater than the second preset fan difference, the transport analysis module uses the third preset fan adjustment coefficient to adjust the flow rate of the first water channel to a corresponding value; the second preset fan difference is greater than the first preset fan difference.

3. The gas purification and waste heat recovery system for blast furnaces, converters and coke ovens according to claim 2, characterized in that: The transport analysis module records the difference between the temperature difference and the preset temperature difference as the coal saving difference, and the analysis module determines the coal saving adjustment method for the flow rate of the second waterway according to the coal saving difference, wherein: If the coal saving difference is less than or equal to the first preset coal saving difference, the transport analysis module uses the first preset coal saving adjustment coefficient to adjust the flow rate of the second waterway to a corresponding value; If the coal saving difference is less than or equal to the second preset coal saving difference and greater than the first preset coal saving difference, the transport analysis module uses the second preset coal saving adjustment coefficient to adjust the flow rate of the second waterway to a corresponding value; If the coal saving difference is greater than the second preset coal saving difference, the transportation analysis module uses the third preset coal saving adjustment coefficient to adjust the flow rate of the second waterway to a corresponding value; the second preset coal saving difference is greater than the first preset coal saving difference.

4. The gas purification and waste heat recovery system for blast furnaces, converters and coke ovens according to claim 3 is characterized in that: The delivery analysis module records the difference between the second preset flow rate and the flow rate as the delivery difference, and determines the delivery adjustment method for the delivery flow rate of nitrogen according to the delivery difference, wherein: If the delivery difference is less than or equal to the first preset delivery difference, the delivery analysis module uses the first preset delivery adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value; If the delivery difference is less than or equal to the second preset delivery difference and greater than the first preset delivery difference, the delivery analysis module uses the second preset delivery adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value; If the delivery difference is greater than the second preset delivery difference, the delivery analysis module uses a third preset delivery adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value; the second preset delivery difference is greater than the first preset delivery difference.

5. The gas purification and waste heat recovery system for blast furnaces, converters and coke ovens according to claim 4, characterized in that: The transport analysis module records the difference between the preset curve slope and the curve slope as the curve difference, and determines the curve adjustment method for the operating power of the purification fan according to the curve difference, wherein: If the curve difference is less than or equal to the first preset curve difference, the delivery analysis module uses the first preset curve adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value; If the curve difference is less than or equal to the second preset curve difference and greater than the first preset curve difference, the delivery analysis module uses the second preset curve adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value; If the curve difference is greater than the second preset curve difference, the delivery analysis module uses the third preset curve adjustment coefficient to adjust the delivery flow rate of the nitrogen to a corresponding value; the second preset curve difference is greater than the first preset curve difference.

6. The gas purification and waste heat recovery system for blast furnaces, converters and coke ovens according to claim 1, characterized in that: The buffer bin is connected to the ash hopper to collect and store ash in the ash hopper; The nitrogen delivery device is also connected to each of the buffer bins, respectively, to maintain a positive pressure in the bin body when the buffer bin is unloading ash.

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