Air-steam heater with dead steam recovery device for boiler

Abstract

The utility model discloses an air-steam heater with a dead steam recovery device for a boiler, which comprises a heater cylinder, an air inlet and an air outlet are respectively arranged at two ends of the heater cylinder, and an input end of a heat exchange tube bundle in the heater cylinder is connected with a high-temperature and high-pressure steam input tube. A heat exchange discharge pipe at the output end of the heat exchange pipe bundle is connected with a dead steam conveying pipe and a condensate water conveying pipe, the dead steam conveying pipe is connected with a steam-water recovery device, and the steam-water recovery device comprises a condensation mechanism and a steam-water recovery device output pipe; the condensate water conveying pipe is connected to a condensate water recycling barrel, a recycling barrel condensate water output pipe is arranged on the condensate water recycling barrel, the recycling barrel condensate water output pipe is connected with a condensate water conveying pump, and the condensate water conveying pump is connected to a deaerator through a delivery pipe; an output pipe of the steam-water recycling device is connected to the condensate water recycling barrel. The waste steam and condensate water recycling device has the advantages that the waste steam and the condensate water are recycled, so that water resources can be greatly saved, and the operation cost of the boiler is effectively reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of boilers, and particularly relates to an air-steam heater. Background Art

[0002] For the waste heat recovery boiler supporting non-ferrous smelting, in order to promote the sulfation reaction of sulfides in flue gas. The sulfation reaction refers to the process in which sulfides react with oxygen to form sulfates under certain conditions. In this process, oxygen-rich air with a certain temperature needs to be injected into the radiant section of the waste heat boiler to promote the sulfation reaction of sulfides, generate sulfates that are not easily adhered, thereby reducing the deposits on the pipe wall and low-temperature corrosion, and ensuring the safe operation of the waste heat boiler.

[0003] Therefore, an air-steam heater is used to heat cold air, and the heated air is then sent into the furnace. The heating medium of the air-steam heater is the high-temperature and high-pressure steam in the drum, and the exhausted steam and condensed water with a higher enthalpy value are discharged from the air-steam heater. At present, the exhausted steam and condensed water with a higher enthalpy value discharged from the air-steam heater are directly discharged into the blowdown flash tank. The condensed water is directly discharged through the blowdown pipe of the blowdown flash tank, and the exhausted steam is vented through the exhaust pipe of the blowdown flash tank.

[0004] The above-mentioned air-steam heater has the following defects: Firstly, it is not fully utilized, resulting in waste of water resources and increasing the operation cost of the boiler; Secondly, it adds burden to the blowdown flash tank, and it is necessary to increase the accommodation space of the blowdown flash tank, resulting in a large occupied space of the equipment and further increasing the operation cost of the boiler. Content of the Utility Model

[0005] The technical problem to be solved by the utility model is to provide an air-steam heater for a boiler with an exhausted steam recovery device, which can reuse the exhausted steam and condensed water, thereby greatly saving water resources and effectively reducing the operation cost of the boiler.

[0006] To solve the above problems, the technical solution adopted by this utility model is: an air-steam heater for boilers with a waste steam recovery device, comprising: a heater cylinder, a heat exchange tube bundle disposed inside the heater cylinder, an air inlet and an air outlet at both ends of the heater cylinder, the air inlet being connected to a cooling air input mechanism, the input end of the heat exchange tube bundle being connected to a high-temperature, high-pressure steam input pipe, the output end of the heat exchange tube bundle being connected to a heat exchange discharge pipe, the heat exchange discharge pipe being connected to a waste steam delivery pipe with a waste steam delivery control valve and a condensate delivery pipe with a condensate delivery control valve and a drain valve, the waste steam delivery pipe being connected to a steam-water recovery device, the steam-water recovery device including a condensation mechanism and a steam-water recovery device output pipe, the condensation mechanism being able to cool steam into condensate; the condensate delivery pipe being connected to a condensate recovery tank, the condensate recovery tank being provided with a condensate output pipe, the condensate output pipe being connected to a condensate delivery pump, the condensate delivery pump being connected to the boiler's deaerator through an external delivery pipe; and the steam-water recovery device output pipe being connected to the condensate recovery tank.

[0007] Furthermore, in the aforementioned air-steam heater for boilers with a waste steam recovery device, the structure of the steam-water recovery device includes: a steam-water recovery cylinder, wherein the output pipe of the steam-water recovery device is connected to the bottom of the steam-water recovery cylinder; the structure of the condensation mechanism includes: a spray head disposed at the top of the steam-water recovery cylinder, wherein the spray head is disposed on a spray pipe, wherein the spray pipe is connected to a cooling water input pipe with a cooling water input control valve; and a safety relief pipe with a safety relief valve is provided at the top of the steam-water recovery cylinder.

[0008] Furthermore, in the aforementioned air-steam heater for boilers with exhaust steam recovery device, a condensate recovery tank is provided with a condensate recovery tank steam discharge pipe at the top, which is connected to the steam-water recovery cylinder.

[0009] Furthermore, in the aforementioned air-steam heater for boilers with exhaust steam recovery device, the heater shell is formed by two heater shell units connected in series. Each heater shell unit is equipped with a heat exchange tube bundle. The input end of the heat exchange tube bundle in each heater shell unit is connected to a high-temperature and high-pressure steam input pipe, and the output end of the heat exchange tube bundle in both heater shells is connected to a heat exchange discharge pipe.

[0010] Furthermore, in the aforementioned air-steam heater for boilers with exhaust steam recovery device, a condensate bypass pipe is connected in parallel to the condensate delivery pipe, and a condensate bypass control valve is installed on the condensate bypass pipe. The two ends of the condensate bypass pipe are respectively connected to the condensate delivery pipes at the outer ends of the condensate delivery control valve and the drain valve.

[0011] Furthermore, in the aforementioned air-steam heater for boilers with exhaust steam recovery device, the cooling air input mechanism includes: a cooling air input pipe, a filter installed on the cooling air input pipe, and the output end of the cooling air input pipe connected to a fan, wherein the fan is connected to the air inlet of the heater body through a pipeline.

[0012] The advantages of this invention are: 1. It can heat cooling air to above 160℃, thereby improving the combustion efficiency of the boiler furnace and effectively preventing large-scale slag formation and low-temperature corrosion on the heating surfaces inside the furnace. 2. The mixture of high-enthalpy steam and condensate output is recovered separately by the steam-water recovery device and the condensate recovery tank, further condensed, and then sent back to the deaerator before being returned to the boiler. This allows water to be reused continuously, greatly saving water resources and effectively reducing boiler operating costs. Furthermore, compared to the traditional method of using a blowdown expansion tank for temporary storage and discharge, it effectively reduces the volume and storage capacity of the boiler-equipped blowdown expansion tank, further lowering boiler operating costs. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the air-steam heater with exhaust steam recovery device for boilers according to this utility model. Detailed Implementation

[0014] The present invention will now be described in further detail with reference to the accompanying drawings and preferred embodiments.

[0015] like Figure 1 As shown, an air-steam heater for boilers with a waste steam recovery device includes: a heater body 1. In this embodiment, the heater body 1 is formed by two heater body units 11 connected in series. Each heater body unit 11 is provided with a heat exchange tube bundle 12. The two ends of the heater body 1 are an air inlet 13 and an air outlet 14, respectively. The air inlet 13 is connected to a cooling air input mechanism 2. The heat exchange tube bundle input end of the heat exchange tube bundle 12 in each heater body unit 11 is connected to a high-temperature and high-pressure steam input pipe 3, and the heat exchange tube bundle output end of the heat exchange tube bundle 12 in each heater body unit 11 is connected to a heat exchange discharge pipe 4. In this embodiment, the cooling air input mechanism 2 includes: a cooling air input pipe 21. A filter 211 is provided on the cooling air input pipe 21. The output end of the cooling air input pipe 21 is connected to a fan 22. The fan 22 is connected to the air inlet 13 of the heater body 1 through a pipeline. The filter 211 can effectively filter out particulate impurities in the air. The heater cylinder 1 consists of two heater cylinder units 11 connected in series. Each heater cylinder unit 11 is equipped with a heat exchange tube bundle 12, which can effectively improve the heating effect of cold air.

[0016] The heat exchange discharge pipe 4 is connected to a waste steam delivery pipe 5 with a waste steam delivery control valve 51 and a condensate delivery pipe 6 with a condensate delivery control valve 61 and a drain valve 62. The waste steam delivery pipe 5 is connected to a steam-water recovery device 7, which includes a condensation mechanism and a steam-water recovery device output pipe 72. The condensation mechanism cools the steam into condensate. In this embodiment, the steam-water recovery device includes a steam-water recovery cylinder 73, with the steam-water recovery device output pipe 72 connected to the bottom of the steam-water recovery cylinder 73. The condensation mechanism includes a spray head 71 located at the top of the steam-water recovery cylinder 73, which is mounted on a spray pipe 74 connected to a cooling water input pipe 75 with a cooling water input control valve 751. A safety relief pipe 732 with a safety relief valve 731 is located at the top of the steam-water recovery cylinder 73. Using the spray head 71 to spray cooling water to condense the steam greatly accelerates the steam condensation rate. The condensation mechanism has a very simple structure, which greatly reduces condensation costs.

[0017] The condensate delivery pipe 6 is connected to the condensate recovery tank 8. The condensate recovery tank 8 is equipped with a condensate output pipe 81 with a condensate output control valve 811. The condensate output pipe 81 is connected to the condensate delivery pump 82, which is connected to the boiler deaerator 9 via an external delivery pipe 83. The steam-water recovery device output pipe 72 is connected to the condensate recovery tank 8, and is equipped with a steam-water recovery device output control valve 721. The top of the condensate recovery tank 8 is equipped with a condensate recovery tank steam discharge pipe 84 with a discharge control valve 841, which is connected to the steam-water recovery cylinder 73.

[0018] In this embodiment, a condensate bypass pipe 63 is connected in parallel to the condensate delivery pipe 6. A condensate bypass control valve 631 is installed on the condensate bypass pipe 63. The two ends of the condensate bypass pipe 63 are respectively connected to the condensate delivery pipe 6 at the outer ends of the condensate delivery control valve 61 and the drain valve 62. The function of the condensate bypass pipe 63 is that, in the event of a fault in the main condensate delivery pipe 6, the condensate bypass control valve 631 can be opened, allowing condensate to be discharged through the condensate bypass pipe 63.

[0019] The working principle is as follows: Cold air is delivered by cooling air input pipe 21, filtered by filter 211, and then delivered by fan 22 through air inlet 13 to heater cylinder 1. The cold air exchanges heat with heat exchange tube bundle 12 in heater cylinder 1. After being heated, the temperature of the cold air rises to above 160°C and is then sent to the salting nozzle 15 in the boiler furnace and injected into the furnace.

[0020] High-temperature, high-pressure steam enters the heat exchange tube bundle 12 of the two heat exchanger shell units 11 through the high-temperature, high-pressure steam input pipe 3, thereby providing heat energy for cooling air. The mixture of exhaust steam and condensate produced after releasing heat energy is output to the heat exchange discharge pipe 4. The exhaust steam in the heat exchange discharge pipe 4 enters the steam-water recovery shell 73 through the exhaust steam conveying pipe 5, and external cooling water is input through the cooling water input pipe 75 and sprayed out by the spray head 71, thereby condensing the steam in the steam-water recovery shell 73 into water. The condensate in the steam-water recovery shell 73 is transported to the condensate recovery tank 8 through the steam-water recovery device output pipe 72.

[0021] The condensate in the heat exchanger discharge pipe 4 is transported to the condensate recovery tank 8 via the condensate delivery pipe 6. The condensate in the condensate recovery tank 8 is then pumped by the condensate delivery pump 82 through the recovery tank condensate output pipe 81 and the external delivery pipe 83 to the deaerator 9 for deoxygenation, and is subsequently returned to the boiler. The steam in the condensate recovery tank 8 enters the steam-water recovery cylinder 73 for cooling through the condensate recovery tank steam discharge pipe 84.

[0022] The above-described air-steam heater for boilers with a waste steam recovery device has the following advantages: 1. It can heat the cooling air to above 160°C, thereby improving the combustion efficiency of the boiler furnace and effectively preventing large-scale slag formation and low-temperature corrosion on the heating surfaces inside the furnace. 2. The mixture of high-enthalpy steam and condensate output is recovered by the steam-water recovery device 7 and the condensate recovery tank 8, respectively, and after further condensation, it is sent back to the deaerator and then back to the boiler. This allows water to be reused continuously, which greatly saves water resources and effectively reduces boiler operating costs. Furthermore, compared to the traditional method of using a blowdown expansion tank for temporary storage and discharge, it effectively reduces the volume and storage capacity of the blowdown expansion tank, further reducing boiler operating costs.

Claims

1. An air-steam heater for boilers with a waste steam recovery system, comprising: A heater cylinder contains a heat exchange tube bundle. The heater cylinder has an air inlet and an air outlet at its two ends. The air inlet is connected to a cooling air input mechanism, and the input end of the heat exchange tube bundle is connected to a high-temperature, high-pressure steam input pipe. The heater cylinder is characterized by: a heat exchange discharge pipe connected to the output end of the heat exchange tube bundle; a waste steam delivery pipe connected to a waste steam delivery control valve and a condensate delivery pipe connected to a condensate delivery control valve and a drain valve; the waste steam delivery pipe connected to a steam-water recovery device; the steam-water recovery device includes a condensation mechanism and a steam-water recovery device output pipe; the condensation mechanism cools steam into condensate; the condensate delivery pipe is connected to a condensate recovery tank; the condensate recovery tank has a condensate output pipe connected to a condensate delivery pump; the condensate delivery pump is connected to the boiler's deaerator via an external delivery pipe; and the steam-water recovery device output pipe is connected to the condensate recovery tank.

2. The air-steam heater for boilers with exhaust steam recovery device according to claim 1, characterized in that: The structure of the steam and water recovery device includes: a steam and water recovery cylinder, wherein the output pipe of the steam and water recovery device is connected to the bottom of the steam and water recovery cylinder; the structure of the condensation mechanism includes: a spray head installed at the top of the steam and water recovery cylinder, wherein the spray head is installed on a spray pipe, and the spray pipe is connected to a cooling water input pipe with a cooling water input control valve; and a safety relief pipe with a safety relief valve is installed at the top of the steam and water recovery cylinder.

3. The air-steam heater for boilers with exhaust steam recovery device according to claim 1, characterized in that: The top of the condensate recovery tank is equipped with a steam discharge pipe, which is connected to the steam and water recovery cylinder.

4. The air-steam heater with exhaust steam recovery device for furnaces according to claim 1, characterized in that: The heater shell is formed by two heater shell units connected in series. Each heater shell unit is equipped with a heat exchange tube bundle. The inlet end of the heat exchange tube bundle in each heater shell unit is connected to the high temperature and high pressure steam inlet pipe. The outlet end of the heat exchange tube bundle in both heater shells is connected to the heat exchange outlet pipe.

5. The air-steam heater for boilers with exhaust steam recovery device according to claim 1, characterized in that: A condensate bypass pipe is connected in parallel to the condensate delivery pipe, and a condensate bypass control valve is installed on the condensate bypass pipe. The two ends of the condensate bypass pipe are respectively connected to the condensate delivery pipes at the outer ends of the condensate delivery control valve and the drain valve.

6. The air-steam heater for boilers with exhaust steam recovery device according to claim 1, characterized in that: The cooling air input mechanism includes: a cooling air input pipe, a filter installed on the cooling air input pipe, and the output end of the cooling air input pipe connected to a fan. The fan is connected to the air inlet of the heater cylinder through a pipeline.

Images