Emptying steam recovery device and method for deaerator in spaceflight furnace conversion process

Abstract

The invention relates to the technical field of deaerators, and particularly discloses a spaceflight furnace conversion process deaerator vent steam recovery device and method.The spaceflight furnace conversion process deaerator vent steam recovery device comprises a deaeration container tank, a hydraulic ejector stretching into the position below the internal liquid level is arranged at the upper end of the deaeration container tank, and the top of the hydraulic ejector is connected with a conveying pipe; an exhaust pipe is arranged at the top of the deoxygenization container tank, the upper end of the exhaust pipe is communicated with a connecting pipe, one end of the connecting pipe is connected with the hydraulic ejector, an emptying valve is arranged at the other end of the connecting pipe, an outer shell of the hydraulic ejector sequentially comprises a suction chamber, a mixing pipe and a diffuser pipe from top to bottom, and a nozzle connected with a conveying pipe is arranged at the top of the suction chamber. A suction inlet communicated with the connecting pipe is formed in the side end of the suction chamber; the deaerator is simple in overall structure and convenient to install, compared with a traditional heat exchanger, the deaerator recycles the heat of the vented steam more directly, the steam demand quantity in the running process of the deaerator is reduced, steam discharge is reduced, and environmental pollution is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of deaerators, and in particular discloses a device and method for recovering vented steam from a deaerator in a conversion process of an aerospace furnace. Background Art

[0002] In the coal chemical production process, the water quality requirements are very high. For example, in the exhaust steam recovery of boiler feed water deaerator, there are high concentrations of O2, CO2 and other gases in the recovered water, which must be removed before returning to the deoxygenated water system. The boiler feed water generally contains dissolved oxygen, which is the main cause of corrosion of the boiler and its auxiliary equipment. The dissolved oxygen in the feed water causes different corrosion to the boiler body, feed water network, etc. in the form of chemical corrosion, electrochemical corrosion, oxygen difference corrosion, etc., so a deaerator is needed to remove oxygen and other non-condensable gases in the water.

[0003] A deaerator is a thermal deoxygenation device. During operation, steam is introduced into the deaerator to increase the water temperature and reduce the partial pressure of gas components, so that oxygen and other non-condensable gases are desorbed from the water body and then discharged from the deaerator container. Although the above deaerator can effectively remove oxygen and other non-condensable gases in the water body, a large amount of flash steam will be discharged during the venting process of the deaerator, resulting in heat waste. In order to avoid steam heat waste, the industry usually uses a heat exchanger to recycle the heat of the venting steam to reduce heat waste.

[0004] For example, the utility model patent with application number 202122328584.3 discloses a deaerator venting steam recovery system, including a deaerator, the steam outlet of the deaerator is connected to the steam venting pipe, and also includes a heat exchanger and a separator tank. The steam outlet of the deaerator is connected to the heat source inlet of the heat exchanger through a recovery pipe, and the heat source outlet of the heat exchanger is connected to the liquid inlet of the separator tank; the gas outlet of the separator tank is connected to one end of the venting pipe, and the other end of the venting pipe is connected to the inlet of the centrifugal fan; the liquid outlet of the separator tank is connected to one end of the condensate pipe, and the other end of the condensate pipe is connected to the inlet of the condensate recovery pump. This patent is to pass the deaerator venting steam into the heat exchanger to realize heat recovery, which reduces the waste of steam heat to a certain extent. However, in the process of deoxygenating the hot water continuously introduced by the deaerator, it is still necessary to continuously use the high-temperature steam introduced from the outside to realize the heating of the water body, and the heat recovery of the high-temperature steam cannot generate steam supplied to the deaerator, resulting in the heat consumption of the deaerator during operation. Therefore, the present application proposes a newly designed aerospace furnace conversion process deaerator vent steam recovery device and method to solve the shortcomings of the existing use of heat exchangers to recover heat from the deaerator vent steam. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a deaerator vent steam recovery device and method which is effective and convenient to install, can well solve the deaerator vent steam recovery problem, and is simple to operate and practical.

[0006] The present invention is achieved through the following technical solutions: A steam recovery device for venting a deaerator in a space furnace conversion process, comprising a deaerator tank, the lower end of which is connected to a water inlet and a drain pipe, a steam inlet pipe is arranged at the lower end of the inner cavity of the deaerator tank, a hydraulic ejector extending below the internal liquid level is arranged at the upper end of the deaerator tank, a delivery pipe is connected to the top of the hydraulic ejector, an exhaust pipe is arranged at the top of the deaerator tank, and the upper end of the exhaust pipe is connected to a connecting pipe, one end of the connecting pipe is connected to the hydraulic ejector, and the other end of the connecting pipe is provided with a vent valve; The outer shell of the hydraulic ejector includes a suction chamber, a mixing tube and a diffuser tube from top to bottom. The top of the suction chamber is provided with a nozzle connected to the delivery pipe, and the side end of the suction chamber is provided with a suction port connected to the connecting pipe. The upper end of the mixing tube is connected to the bottom of the suction chamber and is gradually reduced in diameter downward. The upper end of the diffuser tube is connected to the bottom of the mixing tube and is gradually expanded in diameter downward.

[0007] As a further configuration of the above scheme, the water inlet end is connected to a first control valve, the first control valve is connected to a three-way pipe, one end of the three-way pipe is the water inlet end, and the other end is provided with a second control valve, and the end of the second control valve is connected to the delivery pipe.

[0008] As a further configuration of the above solution, the suction chamber is configured as a cylindrical cavity structure, and the nozzle is disposed at the center of the top of the suction chamber.

[0009] As a further configuration of the above scheme, the lower end of the deoxygenation container tank is connected to a sewage pipe, and the upper end of the sewage pipe is arranged lower than the upper end of the drainage pipe. The sewage pipe and the drainage pipe are respectively provided with a third control valve and a fourth control valve.

[0010] As a further configuration of the above solution, a liquid level gauge is provided at the side end of the deoxygenation container tank, and a pressure gauge is provided at the top of the deoxygenation container tank.

[0011] The present invention also discloses a vent steam recovery method using the vent steam recovery device of the deaerator of the aerospace furnace conversion process, comprising the following steps: The first step is to pass the hot water from the aerospace furnace conversion process into the deaerator tank at the start of the operation, until the hot water level exceeds the bottom of the hydraulic ejector, and then pass the external high-temperature steam into the deaerator tank to further heat the hot water. When the water body is heated, the gas in the water will escape from the water, causing the internal air pressure of the deaerator tank to gradually increase; In the second step, during the stable operation stage of the deaerator, stop introducing high-temperature steam and hot water, introduce hot water into the delivery pipe and deliver it to the nozzle, and spray the hot water into the hydraulic ejector through the nozzle. After the hot water is sprayed into the hydraulic ejector, negative pressure will be formed inside the hydraulic ejector, and the mixed gas at the top of the deaerator tank will be continuously drawn in through the connecting pipe. The inhaled mixed gas and hot water are mixed and flow downward into the deaerator tank. The water vapor in the mixed gas exchanges heat with the hot water and condenses into water to realize the venting steam recovery; In the third step, when the air pressure inside the deaerator tank reaches the set threshold, the safety valve will automatically open to release the pressure, and discharge the non-condensable gas and a small amount of water vapor by regularly opening the vent valve. At the same time, hot water continues to enter the deaerator tank through the hydraulic ejector for deoxygenation, and the deoxygenated hot water is discharged through the drain pipe. Part of the heat in the hot water is converted into steam for the entire deaerator to circulate, without the need to add additional high-temperature steam, thus realizing the direct recycling of the vented steam. Beneficial Effects

[0012] The aerospace furnace conversion process deaerator venting steam recovery device disclosed in the present invention has a simple overall structure and is easy to install. A hydraulic ejector is added to the existing deaerator, and hot water after the equipment runs stably is introduced into the deaerator container tank by the hydraulic ejector through a delivery pipe. At the same time, a suction structure similar to a venturi tube can be formed through a special design of the hydraulic ejector structure, so as to suck the mixed gas analyzed from the hot water, so that the steam in the mixed gas is liquefied by heat exchange with the hot water, while the concentration of other non-condensable gases becomes higher and higher at the upper end of the deaerator container tank, and finally the deaerator can be emptied regularly.

[0013] The hydraulic ejector in the present invention can continuously absorb the analyzed mixed gas, so that the heat of the high-temperature steam in the mixed gas is absorbed and utilized by hot water, and then the heat in the hot water is partially converted into steam for the entire deaerator cycle to remove O2, CO2 and inert gas. After the equipment is running stably, there is no need to add additional high-temperature steam, and the deaerator tank is stable, thereby realizing the direct recovery and utilization of the vented steam. Compared with the traditional heat exchanger, it is more direct to recover and utilize the heat of the vented steam, which not only reduces the steam demand during the operation of the deaerator, but also reduces the discharge of steam and reduces environmental pollution. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for describing the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.

[0015] Figure 1 It is a schematic diagram of the connection structure of various components in the present invention; Figure 2 It is a schematic diagram of the internal structure of the hydraulic ejector in the present invention. DETAILED DESCRIPTION

[0016] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present application.

[0017] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. Figure 1 and attached Figure 2 , and describes the application in detail with reference to embodiments. Example 1

[0018] Example 1 discloses a deaerator venting steam recovery device for aerospace furnace conversion process, see Attachment Figure 1 and attached Figure 2 , including a deaerator tank 1 and a hydraulic ejector 2. The deaerator tank 1 mainly provides a mixing place for the hydraulic ejector 2, and parses out gases such as O2 and CO2. A water inlet is arranged at the lower left end of the deaerator tank 1, and a first control valve 3 is connected to the end of the water inlet. A tee pipe 4 is connected to the first control valve 3. The left end of the tee pipe 4 is a water inlet end, and a second control valve 5 is arranged at the other end. Then, a delivery pipe 6 is connected to the other end of the second control valve 5.

[0019] A steam inlet pipe 12 is provided inside the deoxygenation container tank 1, and one end of the steam inlet pipe 12 extends out of the tank body and is connected to an external steam source. A sewage pipe 7 and a drainage pipe 8 are connected to the lower end of the deoxygenation container tank 1, and the lower ends of the sewage pipe 7 and the drainage pipe 8 are respectively provided with a third control valve 9 and a fourth control valve 10, and the upper end of the drainage pipe 8 is provided higher than the upper end of the sewage pipe 7, so that when the deoxygenation container tank 1 is emptied, the internal water is first discharged through the drainage pipe 8, and then the water and impurities remaining at the bottom of the deoxygenation container tank 1 are discharged through the sewage pipe 7. In addition, in order to facilitate the monitoring of the liquid level inside the deoxygenation container tank 1 and the detection of the internal air pressure, a liquid level gauge 11 is also provided at the right end of the deoxygenation container tank 1, and a pressure gauge and a safety valve (not shown in the figure) are provided at the top of the deoxygenation container tank 1.

[0020] The key design of this embodiment is the hydraulic ejector 2, which is fixedly mounted on the upper end of the deaerator tank 1, and the lower end extends into the lower liquid level of the deaerator tank 1. The ejector shell of the specific hydraulic ejector 2 includes a suction chamber 201, a mixing tube 202 and a diffuser 203 from top to bottom. The suction chamber 201 is similar to a cylindrical cavity with a large diameter. The upper end of the mixing tube 202 is connected to the bottom of the suction chamber 201, and the diameter is gradually reduced downward. The upper end of the diffuser 203 is connected to the bottom of the mixing tube 202, and the diameter is gradually expanded downward, so that a combined tube body similar to an hourglass is formed between the mixing tube 202 and the diffuser 203. A nozzle 204 is provided at the top center of the suction chamber 201, and the nozzle 204 is connected to the end of the delivery pipe 6, so that the hot water sent by the delivery pipe 6 can be sprayed into the suction chamber 201 by the nozzle 204. A suction port 205 is provided at the right section of the suction chamber 201, and then a connecting pipe 13 is connected to the outer end of the suction port 205, and a vent valve 14 is provided at the other end of the connecting pipe 13. Finally, an exhaust pipe 15 is provided at the top of the deaerator tank 1, and the top end of the exhaust pipe 15 is connected to the connecting pipe 13. Example 2

[0021] Example 2 discloses a method for using the venting steam recovery device of the deaerator in the aerospace furnace conversion process in Example 1, and the specific process and principle are as follows: at the initial stage of equipment operation, open the first control valve 3 to directly pass the hot water of the aerospace furnace conversion process from the water inlet into the deaerator tank 1 until the liquid level of the hot water is higher than the lower end of the hydraulic ejector 2, and then pass the external high-temperature steam into the deaerator tank 1 through the steam inlet pipe 12 to further heat the hot water. After the water body is heated, the O2, CO2 and other gases dissolved in the water will escape from the water, and then enter the connecting pipe 13 through the exhaust pipe 15. At this time, the vent valve 14 is in a closed state, and the air pressure inside the deaerator tank 1 gradually increases.

[0022] After the equipment is started and in stable operation, when the internal air pressure of the deaerator tank 1 reaches the set value, the high-temperature steam is stopped and the first control valve 3 is closed, and then the second control valve 4 is opened, so that the hot water is delivered to the nozzle 204 through the delivery pipe 6, and sprayed downward into the hydraulic ejector 2 through the nozzle 204. After the high-pressure hot water passes through the nozzle 204, due to the high speed of the spraying water flow, a negative pressure is formed around the water flow, causing a vacuum in the suction chamber, and the gas gathered at the connecting pipe 13 and the top of the deaerator tank 1 is sucked into the suction chamber 201. At this time, the high-temperature steam in the gas directly contacts the hot water for heat exchange, and most of the steam condenses into water. A small amount of uncondensed steam and non-condensable gas are mixed and squeezed in the mixing tube 202 due to the friction with the high-speed jet water flow, and then discharged through the diffuser 203, so that a higher vacuum is formed in the suction chamber 201, so that the venting steam in the deaerator tank 1 will be continuously sucked into the suction chamber 204, and the speed of the mixed fluid with the hot water will gradually be balanced, so that the kinetic energy and potential energy of the mixed fluid are oppositely converted into heat energy to enter the deaerator gas, and the temperature of the mixed fluid can be achieved by adjusting the amount of water inlet.

[0023] Finally, when the internal air pressure of the deaerator tank 1 reaches the set threshold, the safety valve 16 will open automatically to stabilize the pressure of the deaerator tank. The vent valve 14 can be opened regularly to discharge the non-condensable gas and a small amount of water vapor. The hot water continues to enter the deaerator tank 1 through the hydraulic ejector 2 for deoxygenation, and the deoxygenated hot water is discharged through the drain pipe 8. The heat in the hot water is partially converted into steam for the entire deaerator to circulate. Without the need to add additional high-temperature steam, the temperature of the deaerator tank can be stabilized, so that gases such as O2 and CO2 dissolved in the water can escape from the water, thereby realizing the direct recycling of the vented steam.

[0024] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A steam recovery device for deaerator venting in a space furnace conversion process, comprising a deaerator tank, the lower end of which is connected to a water inlet and a drain pipe, and the lower end of the inner cavity of the deaerator tank is provided with a steam inlet pipe, characterized in that: The upper end of the deaerator tank is provided with a hydraulic ejector extending below the internal liquid level, the top of the hydraulic ejector is connected with a delivery pipe, the top of the deaerator tank is provided with an exhaust pipe, and the upper end of the exhaust pipe is connected with a connecting pipe, one end of the connecting pipe is connected with the hydraulic ejector, and the other end of the connecting pipe is provided with a vent valve; The outer shell of the hydraulic ejector includes a suction chamber, a mixing tube and a diffuser tube from top to bottom. The top of the suction chamber is provided with a nozzle connected to the delivery pipe, and the side end of the suction chamber is provided with a suction port connected to the connecting pipe. The upper end of the mixing tube is connected to the bottom of the suction chamber and is gradually reduced in diameter downward. The upper end of the diffuser tube is connected to the bottom of the mixing tube and is gradually expanded in diameter downward.

2. The aerospace furnace conversion process deaerator venting steam recovery device according to claim 1 is characterized in that: The water inlet end is connected to a first control valve, the first control valve is connected to a three-way pipe, one end of the three-way pipe is a water inlet end, and the other end is provided with a second control valve, and the end of the second control valve is connected to the delivery pipe.

3. The aerospace furnace conversion process deaerator venting steam recovery device according to claim 1, characterized in that: The suction chamber is arranged in a cylindrical cavity-shaped structure, and the nozzle is arranged at the center of the top end of the suction chamber.

4. The aerospace furnace conversion process deaerator venting steam recovery device according to claim 1, characterized in that: The lower end of the deoxygenation container tank is connected with a sewage pipe, and the upper end of the sewage pipe is arranged lower than the upper end of the drainage pipe. The sewage pipe and the drainage pipe are respectively provided with a third control valve and a fourth control valve.

5. The aerospace furnace conversion process deaerator venting steam recovery device according to claim 1, characterized in that: A liquid level gauge is arranged at the side end of the deoxygenation container tank, and a pressure gauge is arranged at the top of the deoxygenation container tank.

6. A method for recovering vent steam using the vent steam recovery device of the deaerator of the aerospace furnace conversion process according to any one of claims 1 to 5, characterized in that: The steps include: At the start of the deaerator operation, hot water from the aerospace furnace conversion process is first introduced into the deaerator tank until the hot water level exceeds the bottom of the hydraulic ejector, and then external high-temperature steam is introduced into the deaerator tank to further heat the hot water. When the water body is heated, the gas in the water will escape from the water, causing the internal air pressure of the deaerator tank to gradually increase; During the stable operation stage of the deaerator, stop introducing high-temperature steam and hot water, introduce hot water into the delivery pipe and deliver it to the nozzle, and spray the hot water into the hydraulic ejector through the nozzle. After the hot water is sprayed into the hydraulic ejector, negative pressure will be formed inside it, and the mixed gas at the top of the deaerator tank will be continuously drawn in through the connecting pipe. The sucked vent steam and hot water will mix downward and flow into the deaerator tank. The water vapor in the mixed gas will exchange heat with the hot water and condense into water to realize the vent steam recovery; When the internal air pressure of the deaerator tank reaches the set threshold, the safety valve will automatically open to release the pressure, and open the vent valve to discharge the non-condensable gas and a small amount of water vapor. At the same time, hot water continues to enter the deaerator tank through the hydraulic ejector for deoxygenation, and the deoxygenated hot water is discharged through the drain pipe. Part of the heat in the hot water is converted into steam for the entire deaerator to circulate, without the need to add additional high-temperature steam, thus realizing the direct recycling of the vented steam.

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