A system for utilizing waste heat from a steam pulverizer

Abstract

The present application relates to a kind of steam powder machine exhaust steam waste heat utilization systems, and more particularly to the technical field of waste heat utilization of titanium dioxide production system, including high-temperature bag filter, desalted water spray tower, exhaust steam heat exchanger, water seal tank, three washing water tank, gas-water heat exchanger, balance water tank, variable frequency water pump unit, hot blast stove and circulating heat medium water, the gas inlet of high-temperature bag filter is connected with the exhaust pipe of steam powder machine.The present application can improve the waste heat utilization efficiency of steam powder machine exhaust steam, save the gas consumption of hot blast stove;It is helpful to improve the recovery and utilization efficiency of water resources, reduce the consumption of desalted water in desalted water spray tower;It is helpful to reduce the air draft power consumption of spray tower outlet side, save operation cost;It is helpful to more intuitively, efficiently monitor the filter bag damage condition of high-temperature bag filter, facilitate the overhaul maintenance of high-temperature bag filter.

Description

Technical Field

[0001] This invention relates to the field of waste heat utilization technology in titanium dioxide production systems, and in particular to a waste heat utilization system for exhaust steam from a steam turbine. Background Technology

[0002] Currently, in titanium dioxide production systems, the exhaust steam temperature at the gas turbine exhaust port is approximately between 90 and 120°C. To utilize the residual heat in the exhaust steam, demineralized water spray heat exchange is typically used. This serves two purposes: firstly, to ensure that the high-temperature bag filter operates under negative pressure; and secondly, after heat exchange, the demineralized water temperature can be raised from ambient temperature to 60-85°C for use in the third washing stage of titanium dioxide post-processing.

[0003] The main problem with the above solution is that, in order to ensure that the high-temperature bag filter operates under negative pressure, the amount of spray water used is much greater than the amount of water used for the third washing, resulting in an excess of high-temperature water. At the same time, the temperature of the exhaust gas after the spray tower is 60-80℃, and the waste heat temperature of the exhaust gas is relatively high, which has the value of further recovery and utilization.

[0004] Therefore, those skilled in the art urgently need to develop a waste heat utilization system for steam pulverizers to solve the above-mentioned technical problems. Summary of the Invention

[0005] The main objective of this invention is to provide a waste heat recovery system for pulverized coal mills, which can efficiently recover and utilize the waste heat of pulverized coal mills while further saving water resources, and at the same time facilitates intuitive monitoring of filter bag damage in high-temperature bag filters.

[0006] To achieve the above objectives, the present invention is implemented according to the following technical solution:

[0007] A waste heat utilization system for steam pulverizer includes a high-temperature bag filter, a demineralized water spray tower, a waste steam heat exchanger, a water seal tank, a three-wash water tank, a gas-water heat exchanger, a balance water tank, a variable frequency water pump unit, a hot air furnace, and circulating heat transfer medium water. The air inlet of the high-temperature bag filter is connected to the air outlet pipe of the steam pulverizer.

[0008] Exhaust steam heat exchanger: Connected between the high-temperature bag filter and the demineralized water spray tower, it uses the high-temperature exhaust steam (90-120°C) discharged from the high-temperature bag filter to heat the circulating heat medium water to 80-95°C; and the exhaust steam condensate in the exhaust steam heat exchanger flows into the water seal tank through the discharge pipe.

[0009] Demineralized water spray tower: The exhaust steam discharged from the exhaust steam heat exchanger is sprayed in an empty tower with demineralized water. The spray water collected at the bottom of the demineralized water spray tower is divided into the three washing water tank and the balance water tank for use.

[0010] Water seal tank: Used to collect condensate discharged from the exhaust steam heat exchanger. By observing whether the condensate in the water seal tank turns white, it can be determined whether the filter bags of the high-temperature bag filter are damaged. At the same time, it prevents the negative pressure inside the exhaust steam heat exchanger from being too high and causing deformation of the tank. The overflow water from the water seal tank flows into the three-wash water tank through the overflow water pipe.

[0011] Balance water tank: Connected between the exhaust steam heat exchanger and the variable frequency water pump unit, the heat transfer water after heat exchange in the exhaust steam heat exchanger is introduced into the balance water tank. The balance water tank is equipped with a steam outlet and a heat transfer water inlet; the heat transfer water inlet is connected to the spray water in the demineralized water spray tower through a water supply pipeline; the heat transfer water outlet of the balance water tank is connected to the variable frequency water pump unit.

[0012] The variable frequency water pump unit is used to transport the heat medium water in the balance water tank to the air-water heat exchanger and provide circulation power for the circulating heat medium water;

[0013] Gas-water heat exchanger: The heat transfer water from the variable frequency water pump unit heats the primary and secondary air of the hot air furnace from room temperature to 65-90℃, which reduces the gas consumption of the hot air furnace in the flash evaporation process of titanium dioxide. After the heat transfer water is cooled to 50-75℃ in the gas-water heat exchanger, it re-enters the exhaust steam heat exchanger to be heated again, thus realizing the recycling of the heat transfer water.

[0014] Preferably, the waste steam heat exchanger is a shell-and-tube heat exchanger, with circulating heat transfer medium water in the tube side and high-temperature waste steam from a high-temperature bag filter in the shell side. A cone hopper is provided at the bottom of the shell of the waste steam heat exchanger, and the waste steam condensate in the cone hopper flows to the water seal tank through the discharge pipe for timely collection of condensate.

[0015] Preferably, a spraying device is installed inside the top shell of the waste steam heat exchanger. The spraying water for the spraying device comes from the spraying water at the bottom of the demineralized water spraying tower, and the temperature of the spraying water is 50-80℃. Compared with room temperature water, using spraying water will not affect the temperature of the three-wash water in the waste steam heat exchanger due to frequent use of the spraying device, thus ensuring the water washing efficiency.

[0016] Preferably, the spraying device includes a spraying grid pipe connected to the top shell of the waste steam heat exchanger. The spraying grid pipe is evenly distributed with nozzles facing the heat exchange tubes in the tube side of the waste steam heat exchanger. The water inlet end of the spraying grid pipe is connected to the spraying water in the demineralized water spraying tower through a spraying water connecting pipe. A spraying pump is provided on the spraying water connecting pipe. The spraying device can flush the heat exchange tubes in the waste steam heat exchanger as needed to avoid scaling and help ensure heat exchange efficiency.

[0017] Preferably, the variable frequency water pump unit includes an inlet header, an outlet header, a first pumping pipe, and a second pumping pipe. The first and second pumping pipes are respectively equipped with an inlet valve, a pressure gauge, a Y-type filter, a first check valve, a vertical variable frequency water pump, a second check valve, and an outlet valve along the medium flow direction. The inlet ends of the first and second pumping pipes are connected to the inlet header, and a flow meter is installed on the inlet header. The outlet ends of the first and second pumping pipes are respectively connected to the outlet header. The temperature of the heat transfer medium is adjusted by adjusting the operating frequency of the vertical variable frequency water pump. The Y-type filter is used to filter impurities and titanium dioxide particles in the circulating heat transfer medium.

[0018] Preferably, the air-water heat exchanger includes a heat exchange box, with an air inlet on one side and an air outlet on the other side. The air inlet is connected to an axial flow fan, and the air inlet of the axial flow fan is equipped with an air filter. The air outlet is connected to the primary air duct and the secondary air duct of the hot blast furnace, respectively. A heat exchange jacket is provided on the outside of the heat exchange box, with a hot medium water inlet and a hot medium water outlet on the jacket. A drain valve is also provided at the bottom of the heat exchange jacket.

[0019] Preferably, the outlet of the demineralized water spray tower is connected to an induced draft fan, and the outlet of the induced draft fan is connected to a tail gas exhaust pipe.

[0020] Preferably, a first connecting pipe is provided between the air outlet of the high-temperature bag filter and the air inlet of the demineralized water spray tower, and a first shut-off valve is provided on the first connecting pipe. The first connecting pipe is connected to both an exhaust steam heat exchanger inlet pipe and an exhaust steam heat exchanger outlet pipe. The exhaust steam heat exchanger inlet pipe and outlet pipe are respectively connected to the upstream and downstream pipe sections of the first shut-off valve. An inlet valve is provided on the exhaust steam heat exchanger inlet pipe, and an outlet valve is provided on the exhaust steam heat exchanger outlet pipe. The air inlet and outlet of the exhaust steam heat exchanger are connected to the exhaust steam heat exchanger inlet pipe and outlet pipe, respectively. When online maintenance of the exhaust steam heat exchanger or the heat transfer fluid circulation pipeline is required, opening the first shut-off valve and closing the inlet valve on the exhaust steam heat exchanger inlet pipe and the outlet valve on the exhaust steam heat exchanger outlet pipe will still ensure the normal operation of the steam turbine system.

[0021] This invention also includes other components that enable its normal use, all of which employ conventional techniques in the art. Furthermore, devices and components not limited in this invention employ conventional techniques in the art, such as steam pulverizers, high-temperature bag filters, demineralized water spray towers, hot air furnaces, and vertical variable frequency water pumps. In specific implementations, those skilled in the art can select appropriate equipment or component models according to the specific working scenario.

[0022] The working principle of this invention is as follows: This application recovers part of the waste heat in the high-temperature waste steam at the outlet of the high-temperature bag filter into the circulating heat transfer medium water through a waste steam heat exchanger. On the one hand, this reduces the volumetric flow rate of the waste steam entering the spray tower, saving system exhaust power consumption. The waste steam entering the spray tower is further discharged after spray heat exchange. The spray water absorbs part of the heat in the waste steam and is discharged into the three-wash water tank, which is used as the three-wash water for titanium dioxide post-treatment, further improving the waste heat recovery efficiency. On the other hand, the waste steam heat exchanger condenses the water vapor in the waste steam, recovering water resources. At the same time, the water seal tank allows for a direct assessment of the damage to the high-temperature bag filter bags by observing the color change of the condensate. If the filter bags are damaged, the condensate will turn white (caused by an increase in titanium dioxide concentration). The water seal tank provides a certain degree of safety protection for the waste steam heat exchanger, preventing the deformation of the tank due to excessive negative pressure inside the tank when the equipment malfunctions. In addition, after absorbing heat from the heat transfer water and entering the balance tank, the water vapor in the heat transfer water is discharged through the exhaust port and then supplied to the gas-water heat exchanger by the variable frequency water pump unit. This heats the primary and secondary air of the hot blast furnace from room temperature to 65-90°C, thereby reducing the gas consumption of the hot blast furnace in the titanium dioxide flash evaporation process. After the heat transfer water is cooled to 50-75°C in the gas-water heat exchanger, it re-enters the exhaust steam heat exchanger for heat exchange and temperature increase, thus realizing the recycling of the heat transfer water and achieving high-efficiency utilization of exhaust steam waste heat.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] (1) Improve the waste heat utilization efficiency of the exhaust steam of the steam pulverizer and save the gas consumption of the hot blast stove;

[0025] (2) It helps to improve the efficiency of water resource recycling and utilization, and reduce the consumption of demineralized water in the demineralized water spray tower.

[0026] (3) It helps reduce the exhaust power consumption on the air outlet side of the spray tower and saves operating costs;

[0027] (4) It helps to monitor the filter bag damage of high temperature bag filters more intuitively and efficiently, and facilitates the inspection and maintenance of high temperature bag filters. Attached Figure Description

[0028] Figure 1 This is an overall system connection diagram of the present invention;

[0029] Figure 2 This is a schematic diagram of the overall structure of the exhaust steam heat exchanger.

[0030] Figure 3 This is a schematic diagram of the overall structure of a gas-water heat exchanger.

[0031] Figure 4 This is a three-dimensional structural diagram of a variable frequency water pump unit. Detailed Implementation

[0032] The present invention will be further described below with reference to specific embodiments and accompanying drawings. The illustrative embodiments and descriptions herein are used to explain the present invention, but are not intended to limit the present invention.

[0033] Example

[0034] like Figures 1-4 As shown, this embodiment proposes a waste heat utilization system for steam pulverizers, including a high-temperature bag filter 1, a demineralized water spray tower 2, a waste steam heat exchanger 3, a water seal tank 4, a three-wash water tank 5, a gas-water heat exchanger 6, a balance water tank 7, a variable frequency water pump unit 8, a hot air furnace 9, and circulating heat transfer medium water. The air inlet of the high-temperature bag filter is connected to the air outlet pipe 10 of the steam pulverizer, and the air outlet of the demineralized water spray tower is connected to an induced draft fan 11. The air outlet of the induced draft fan is connected to a tail gas exhaust pipe.

[0035] Waste steam heat exchanger: Connected between the high-temperature bag filter and the demineralized water spray tower, it uses the high-temperature waste steam discharged from the high-temperature bag filter at 90-120°C to heat the circulating heat transfer medium water to 80-95°C; and the waste steam condensate in the waste steam heat exchanger flows into the water seal tank through the discharge pipe 36; in this embodiment, when the waste steam heat exchanger is running for the first time, the circulating heat transfer medium water is the demineralized water newly added to the waste heat utilization system of the steam pulverizer. After the circulating heat transfer medium water in the waste heat utilization system of the steam pulverizer is circulating normally, the circulating heat transfer medium water at the inlet of the waste steam heat exchanger is the heat transfer medium water from the outlet of the gas-water heat exchanger.

[0036] Demineralized water spray tower: The exhaust steam discharged from the exhaust steam heat exchanger is sprayed in an empty tower with demineralized water. The spray water collected at the bottom of the demineralized water spray tower is divided into the three washing water tank and the balance water tank for use.

[0037] Water seal tank: Used to collect condensate discharged from the exhaust steam heat exchanger. By observing whether the condensate in the water seal tank turns white, it can be determined whether the filter bag of the high-temperature bag filter is damaged. At the same time, it prevents the negative pressure inside the exhaust steam heat exchanger from being too large and causing deformation of the tank. The overflow water of the water seal tank flows into the three-wash water tank through the overflow water pipe 12.

[0038] Balance water tank: Connected between the exhaust steam heat exchanger and the variable frequency water pump unit, the heat transfer water after heat exchange in the exhaust steam heat exchanger is introduced into the balance water tank. The balance water tank is equipped with a steam outlet 13 and a heat transfer water inlet; the heat transfer water inlet is connected to the spray water in the demineralized water spray tower through a water supply pipeline 14; the heat transfer water outlet of the balance water tank is connected to the variable frequency water pump unit.

[0039] The variable frequency water pump unit is used to transport the heat medium water in the balance water tank to the air-water heat exchanger and provide circulation power for the circulating heat medium water;

[0040] Gas-water heat exchanger: The heat transfer water from the variable frequency water pump unit heats the primary and secondary air of the hot air furnace from room temperature to 65-90℃, which reduces the gas consumption of the hot air furnace in the flash evaporation process of titanium dioxide. After the heat transfer water is cooled to 50-75℃ in the gas-water heat exchanger, it re-enters the exhaust steam heat exchanger to be heated again, thus realizing the recycling of the heat transfer water.

[0041] Specifically, the exhaust steam heat exchanger adopts a shell-and-tube heat exchanger. The medium in the tube side is circulating heat transfer medium water, and the medium in the shell side is high-temperature exhaust steam from a high-temperature bag filter. The bottom of the shell of the exhaust steam heat exchanger is provided with a cone hopper 35. The exhaust steam condensate in the cone hopper flows to the water seal tank through the discharge pipe for timely collection of condensate.

[0042] The waste steam heat exchanger is equipped with a spray device 31 inside its top shell. The spray water used in this device comes from the bottom of the demineralized water spray tower, and the temperature of the spray water is 50-80℃. Compared to ambient temperature water, using spray water ensures that the temperature of the three-stage washing water is not affected by the frequent use of the spray device, thus guaranteeing the washing efficiency.

[0043] More specifically, the spraying device includes a spraying grid pipe connected to the top shell of the waste steam heat exchanger. The spraying grid pipe is evenly distributed with nozzles facing the heat exchange tubes 32 in the tube side of the waste steam heat exchanger. The water inlet end of the spraying grid pipe is connected to the spraying water in the demineralized water spraying tower through a spraying water connecting pipe 33. A spraying pump 34 is provided on the spraying water connecting pipe. The spraying device can flush the heat exchange tubes in the waste steam heat exchanger as needed to avoid scaling and help ensure heat exchange efficiency.

[0044] In this embodiment, the variable frequency water pump unit includes an inlet header 81, an outlet header 82, a first pumping pipe, and a second pumping pipe. The first and second pumping pipes are respectively equipped with an inlet valve 83, a pressure gauge 84, a Y-type filter 85, a first check valve 86, a vertical variable frequency water pump 87, a second check valve 88, and an outlet valve 89 along the medium flow direction. The inlet ends of the first and second pumping pipes are connected to the inlet header, and a flow meter 80 is installed on the inlet header. The outlet ends of the first and second pumping pipes are respectively connected to the outlet header. The temperature of the heat transfer medium is adjusted by adjusting the operating frequency of the vertical variable frequency water pump. The Y-type filter is used to filter impurities and titanium dioxide particles in the circulating heat transfer medium.

[0045] Specifically, the air-water heat exchanger includes a heat exchange box 61, with an air inlet on one side and an air outlet on the other side. The air inlet is connected to an axial flow fan 62, and the air inlet of the axial flow fan is equipped with an air filter 63. The air outlet is connected to the primary air duct 91 and the secondary air duct 92 of the hot blast furnace, respectively. A heat exchange jacket 64 is provided on the outside of the heat exchange box, with a hot medium water inlet and a hot medium water outlet. A drain valve 65 is also provided at the bottom of the heat exchange jacket.

[0046] More specifically, a first connecting pipe 15 is provided between the air outlet of the high-temperature bag filter and the air inlet of the demineralized water spray tower, and a first shut-off valve 16 is provided on the first connecting pipe. An exhaust steam heat exchanger inlet pipe 17 and an exhaust steam heat exchanger outlet pipe 18 are respectively connected to the first connecting pipe. The exhaust steam heat exchanger inlet pipe and exhaust steam heat exchanger outlet pipe are respectively connected to the upstream and downstream pipe sections of the first shut-off valve. An inlet valve 19 is provided on the exhaust steam heat exchanger inlet pipe, and an outlet valve is provided on the exhaust steam heat exchanger outlet pipe. The exhaust steam heat exchanger inlet and outlet are respectively connected to the exhaust steam heat exchanger inlet pipe and exhaust steam heat exchanger outlet pipe. When online maintenance of the exhaust steam heat exchanger or the heat transfer medium circulation pipeline is required, opening the first shut-off valve and closing the inlet valve on the exhaust steam heat exchanger inlet pipe and the outlet valve on the exhaust steam heat exchanger outlet pipe will still ensure the normal operation of the steam pulverizer system.

[0047] The working principle of this invention is as follows: This application recovers part of the waste heat in the high-temperature waste steam at the outlet of the high-temperature bag filter into the circulating heat transfer medium water through a waste steam heat exchanger. On the one hand, this reduces the volumetric flow rate of the waste steam entering the spray tower, saving system exhaust power consumption. The waste steam entering the spray tower is further discharged after spray heat exchange. The spray water absorbs part of the heat in the waste steam and is discharged into the three-wash water tank, which is used as the three-wash water for titanium dioxide post-treatment, further improving the waste heat recovery efficiency. On the other hand, the waste steam heat exchanger condenses the water vapor in the waste steam, recovering water resources. At the same time, the water seal tank allows for a direct assessment of the damage to the high-temperature bag filter bags by observing the color change of the condensate. If the filter bags are damaged, the condensate will turn white (caused by an increase in titanium dioxide concentration). The water seal tank provides a certain degree of safety protection for the waste steam heat exchanger, preventing the deformation of the tank due to excessive negative pressure inside the tank when the equipment malfunctions. In addition, after absorbing heat from the heat transfer water and entering the balance tank, the water vapor in the heat transfer water is discharged through the exhaust port and then supplied to the gas-water heat exchanger by the variable frequency water pump unit. This heats the primary and secondary air of the hot blast furnace from room temperature to 65-90°C, thereby reducing the gas consumption of the hot blast furnace in the titanium dioxide flash evaporation process. After the heat transfer water is cooled to 50-75°C in the gas-water heat exchanger, it re-enters the exhaust steam heat exchanger for heat exchange and temperature increase, thus realizing the recycling of the heat transfer water and achieving high-efficiency utilization of exhaust steam waste heat.

[0048] The technical solutions of the present invention are not limited to the specific embodiments described above. Any technical modifications made in accordance with the technical solutions of the present invention fall within the protection scope of the present invention.

Claims

1. A waste heat recovery system for steam pulverizers, comprising a high-temperature bag filter and a demineralized water spray tower, wherein the inlet of the high-temperature bag filter is connected to the outlet pipe of the steam pulverizer, characterized in that, It also includes a waste steam heat exchanger, a water seal tank, a three-wash water tank, a gas-water heat exchanger, a balance water tank, a variable frequency water pump unit, a hot air furnace, and circulating heat transfer medium water; Exhaust steam heat exchanger: Connected between the high-temperature bag filter and the demineralized water spray tower, it uses the high-temperature exhaust steam discharged from the high-temperature bag filter to heat the circulating heat medium water to 80-95℃; and the exhaust steam condensate in the exhaust steam heat exchanger flows into the water seal tank through the discharge pipe. Demineralized water spray tower: The exhaust steam discharged from the exhaust steam heat exchanger is sprayed in an empty tower with demineralized water. The spray water collected at the bottom of the demineralized water spray tower is divided into the three washing water tank and the balance water tank for use. Water seal tank: Used to collect condensate discharged from the exhaust steam heat exchanger. By observing whether the condensate in the water seal tank turns white, it can be determined whether the filter bags of the high-temperature bag filter are damaged. At the same time, it prevents the negative pressure inside the exhaust steam heat exchanger from being too high and causing deformation of the tank. The overflow water from the water seal tank flows into the three-wash water tank through the overflow water pipe. Balance water tank: Connected between the exhaust steam heat exchanger and the variable frequency water pump unit, the heat transfer water after heat exchange in the exhaust steam heat exchanger is introduced into the balance water tank. The balance water tank is equipped with a steam outlet and a heat transfer water inlet; the heat transfer water inlet is connected to the spray water in the demineralized water spray tower through a water supply pipeline; the heat transfer water outlet of the balance water tank is connected to the variable frequency water pump unit. Variable frequency water pump unit: used to transport the heat medium water in the balance water tank to the air-water heat exchanger and provide circulation power for the circulating heat medium water; Gas-water heat exchanger: The heat transfer water from the variable frequency water pump unit heats the primary and secondary air of the hot air furnace from room temperature to 65-90℃, which reduces the gas consumption of the hot air furnace in the flash evaporation process of titanium dioxide. After the heat transfer water is cooled to 50-75℃ in the gas-water heat exchanger, it re-enters the exhaust steam heat exchanger to be heated again, thus realizing the recycling of the heat transfer water.

2. The waste heat recovery system for steam pulverizers according to claim 1, characterized in that: The exhaust steam heat exchanger is a shell-and-tube heat exchanger. The medium in the tube side is circulating heat transfer medium water, and the medium in the shell side is high-temperature exhaust steam from a high-temperature bag filter. The bottom of the shell of the exhaust steam heat exchanger is equipped with a cone hopper, and the exhaust steam condensate in the cone hopper flows to the water seal tank through the discharge pipe.

3. The waste heat recovery system for steam pulverizers according to claim 2, characterized in that: The top shell of the waste steam heat exchanger is equipped with a spray device. The spray water for the spray device comes from the spray water at the bottom of the demineralized water spray tower, and the temperature of the spray water is 50-80℃.

4. The waste heat recovery system for steam pulverizers according to claim 3, characterized in that: The spraying device includes a spraying grid pipe connected to the top shell of the waste steam heat exchanger. The spraying grid pipe is evenly distributed with nozzles facing the heat exchange tubes in the tube side of the waste steam heat exchanger. The water inlet end of the spraying grid pipe is connected to the spraying water in the demineralized water spraying tower through a spraying water connecting pipe, and a spraying pump is provided on the spraying water connecting pipe.

5. A waste heat recovery system for steam pulverizers according to claim 1, characterized in that: The variable frequency water pump unit includes an inlet header, an outlet header, a first pumping pipe, and a second pumping pipe. The first and second pumping pipes are respectively equipped with an inlet valve, a pressure gauge, a Y-type filter, a first check valve, a vertical variable frequency water pump, a second check valve, and an outlet valve along the medium flow direction. The inlet ends of the first and second pumping pipes are respectively connected to the inlet header. The inlet header is equipped with a flow meter. The outlet ends of the first and second pumping pipes are respectively connected to the outlet header.

6. The waste heat recovery system for steam pulverizers according to claim 1, characterized in that: The air-water heat exchanger includes a heat exchange box with an air inlet on one side and an air outlet on the other side. The air inlet is connected to an axial flow fan, and the air inlet of the axial flow fan is equipped with an air filter. The air outlet is connected to the primary air duct and the secondary air duct of the hot blast stove, respectively. A heat exchange jacket is provided on the outside of the heat exchange box, and the heat exchange jacket is provided with a hot medium water inlet and a hot medium water outlet. A drain valve is also provided at the bottom of the heat exchange jacket.

7. A waste heat recovery system for steam pulverizers according to claim 1, characterized in that: The outlet of the demineralized water spray tower is connected to an induced draft fan, and the outlet of the induced draft fan is connected to a tail gas exhaust pipe.

8. A waste heat recovery system for steam pulverizers according to any one of claims 1 to 7, characterized in that: A first connecting pipe is provided between the air outlet of the high-temperature bag filter and the air inlet of the demineralized water spray tower. A first shut-off valve is provided on the first connecting pipe. An air inlet pipe and an air outlet pipe of the waste steam heat exchanger are respectively connected to the first connecting pipe. The air inlet pipe and the air outlet pipe of the waste steam heat exchanger are respectively connected to the upstream and downstream pipe sections of the first shut-off valve. An air inlet valve is provided on the air inlet pipe of the waste steam heat exchanger, and an air outlet valve is provided on the air outlet pipe of the waste steam heat exchanger. The air inlet and air outlet of the waste steam heat exchanger are respectively connected to the air inlet pipe and the air outlet pipe of the waste steam heat exchanger.

Images