Steam condensate water cooling and recycling energy-saving system of air heater in tobacco processing

Abstract

The invention discloses a steam condensate cooling and recycling energy-saving system of an air heater in tobacco processing, and belongs to the technical field of tobacco processing. The steam condensate cooling and recycling energy-saving system of the air heater in tobacco processing comprises the air heater, a preheating unit and a recycling unit, a steam heat exchange cavity and an air conveying channel are arranged in the air heater, and the preheating unit comprises an air preheater and a first liquid discharging pipeline; one end of the first liquid discharge pipeline is communicated with an outlet of a steam heat exchange cavity of the air heater, the other end of the first liquid discharge pipeline is communicated with an inlet of a condensate water heat exchange cavity of the air preheater, and a drain valve is arranged on the first liquid discharge pipeline; the recycling unit comprises a condensate water recycling pipe and a water collecting tank, one end of the condensate water recycling pipe is communicated with an outlet of the condensate water heat exchange cavity of the air preheater, and the other end of the condensate water recycling pipe is communicated with the water collecting tank. The steam condensate water from the air heater can be reutilized, and the energy-saving efficiency of the cigarette production line is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of tobacco processing, and particularly to a steam condensate cooling and recycling energy-saving system for an air heater in tobacco processing. Background Art

[0002] As a core pillar facility in the tobacco industry system, the cigarette production line undertakes the crucial mission of transforming raw tobacco leaf materials into finished cigarettes that meet the standards. Relying on highly automated, continuous, and intelligent precision process flows, it realizes the efficient operation of the entire chain from raw material processing to finished product packaging. In this complex and delicate production system, the drum type humidifying machine, drum type flavoring machine, and drum thin plate type tobacco drying machine together constitute an indispensable key supporting equipment matrix on the cigarette production line.

[0003] The drum type humidifying machine and the drum type flavoring machine are the core equipment in the tobacco leaf pretreatment stage. Inside the equipment, hot air with high temperature and appropriate humidity is precisely controlled and circulated. These hot air gradually penetrate into the fiber structure of the tobacco leaves. During this process, the moisture content and temperature of the tobacco leaves are significantly increased. The originally shriveled and brittle tobacco leaves gradually become soft and loose, and their internal toughness is significantly enhanced, thus greatly improving the tolerance and plasticity of the tobacco leaves in the subsequent processing, laying a solid foundation for the subsequent fine processing. The drum thin plate type tobacco drying machine plays a key role in the shaping and quality setting of tobacco shreds. After the tobacco shreds undergo preliminary processing and enter the drying machine, at this time, the hot air with high temperature and dryness, like a precise regulator, quickly and effectively removes the excess moisture in the tobacco shreds, ensuring that the tobacco shreds reach the ideal dryness. At the same time, by precisely controlling the temperature and flow rate of the hot air, the drying machine can also maintain the temperature stability of the tobacco shreds during the moisture removal process, avoiding the decline in the quality of the tobacco shreds caused by temperature fluctuations, thus ensuring that each tobacco shred can reach the best state with uniform color, pure aroma, and mellow taste.

[0004] During the operation of the above three key equipment, the hot air heating system is undoubtedly the core power source. This system heats the cold air that has been precisely filtered and adjusted to the exact temperature required by the process through the built-in air heater, providing a continuous and stable heat source inside the equipment. The heat source of the air heater comes from process steam, an efficient and clean energy form. When the high-temperature steam flows through the inside of the heater, the latent heat it contains is efficiently transferred to the flowing air, causing the air temperature to rise rapidly. At the same time, after the steam releases the latent heat, it gradually condenses into liquid condensate, and this condensate needs to be discharged from the system in a timely manner to prevent damage to the equipment or affect the heating efficiency.

[0005] However, during the process of discharging the condensed water, a physical phenomenon that cannot be ignored occurs quietly - flashing. Due to the significant change in pressure before and after the steam trap, when the high-temperature condensed water passes through the steam trap, its internal pressure drops suddenly, causing part of the condensed water to vaporize instantly and form secondary steam. In this process, not only is there a large amount of heat released disorderly, but it may also pose a high-temperature threat to the sewage pipeline and the factory environment. More seriously, the heat that could have been recycled is wasted with the direct discharge of the secondary steam and high-temperature condensed water, posing a severe challenge to the enterprise's energy utilization efficiency and cost control.

[0006] This section provides background information related to the present application, which is not necessarily prior art. Summary of the Invention

[0007] The purpose of the present invention is to provide a steam condensed water cooling, recovery and energy-saving system for an air heater in tobacco processing, which can reuse the steam condensed water from the air heater, reduce the energy consumption of the air heater, improve the energy-saving efficiency of the cigarette production line, and avoid causing high temperature in the sewage pipeline and the factory environment.

[0008] To achieve the above object, the following technical solutions are provided:

[0009] A steam condensed water cooling, recovery and energy-saving system for an air heater in tobacco processing, comprising an air heater, wherein a steam heat exchange chamber and an air conveying channel are arranged in the air heater, and the process steam in the steam heat exchange chamber is used to heat the air in the air conveying channel. The system further includes:

[0010] A preheating unit, including an air preheater and a first drain pipe. A condensed water heat exchange chamber and an air transmission channel are arranged in the air preheater. The condensed water in the condensed water heat exchange chamber is used to preheat the air in the air transmission channel. The output end of the air transmission channel of the air preheater is communicated with the input end of the air conveying channel of the air heater. One end of the first drain pipe is communicated with the outlet of the steam heat exchange chamber of the air heater, and the other end of the first drain pipe is communicated with the inlet of the condensed water heat exchange chamber of the air preheater. A steam trap is arranged on the first drain pipe;

[0011] A recovery unit, including a condensed water recovery pipe and a water collection tank. One end of the condensed water recovery pipe is communicated with the outlet of the condensed water heat exchange chamber of the air preheater, and the other end of the condensed water recovery pipe is communicated with the water collection tank.

[0012] As an alternative solution of the steam condensed water cooling, recovery and energy-saving system for an air heater in tobacco processing, a first stop valve, a first filter, the steam trap and a first check valve are sequentially arranged on the first drain pipe along its extending direction.

[0013] As an alternative solution for the steam condensate cooling recovery and energy-saving system of the air heater in tobacco processing, the preheating unit further includes:

[0014] A tee pipe, the first interface of the tee pipe is communicated with the outlet of the steam heat exchange chamber of the air heater, and the second interface of the tee pipe is communicated with the inlet of the condensate heat exchange chamber of the air preheater;

[0015] A second drain pipe, one end of the second drain pipe is communicated with the third interface of the tee pipe, and a condensate discharge valve is arranged on the second drain pipe.

[0016] As an alternative solution for the steam condensate cooling recovery and energy-saving system of the air heater in tobacco processing, a second stop valve, a second filter, the condensate discharge valve and a second check valve are sequentially arranged on the second drain pipe along the extending direction of the second drain pipe.

[0017] As an alternative solution for the steam condensate cooling recovery and energy-saving system of the air heater in tobacco processing, it further includes a process steam delivery pipe, and one end of the process steam delivery pipe is communicated with the inlet of the steam heat exchange chamber of the air heater.

[0018] As an alternative solution for the steam condensate cooling recovery and energy-saving system of the air heater in tobacco processing, a vacuum-breaking valve and an air exhaust valve are arranged on the process steam delivery pipe.

[0019] As an alternative solution for the steam condensate cooling recovery and energy-saving system of the air heater in tobacco processing, at least two groups of the preheating units are provided. The air preheater of one group of the preheating units is used to access the condensate from the air heater through the first drain pipe, and the air preheater of the other group of the preheating units is used to access the condensate from the cabinet manifold through the first drain pipe.

[0020] As an alternative solution for the steam condensate cooling recovery and energy-saving system of the air heater in tobacco processing, the water collection tank is provided with an emptying pipe, and the emptying pipe is communicated with the accommodating cavity of the water collection tank.

[0021] As an alternative solution for the steam condensate cooling recovery and energy-saving system of the air heater in tobacco processing, the water collection tank is provided with a liquid level sensor and a temperature sensor, and the recovery unit further includes a condensate recovery electric pump, and the outlet of the water collection tank is communicated with the condensate recovery electric pump.

[0022] As an alternative solution for the steam condensate cooling recovery and energy-saving system of the air heater in tobacco processing, the recovery unit further includes:

[0023] Control cabinet, the condensate recovery electric pump, the liquid level sensor and the temperature sensor are all electrically connected to the control cabinet.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] The steam condensate cooling and recovery energy-saving system of the air heater in tobacco processing provided by the present invention connects the air preheater of the preheating unit to the front end of the air preheater, that is, the output end of the air transmission channel of the air preheater is communicated with the input end of the air delivery channel of the air heater, so that the air first enters the air preheater for preheating and then enters the air heater for full heating. It can not only reuse the steam condensate from the air heater, reduce the energy consumption of the air heater, improve the energy-saving efficiency of the cigarette production line, but also avoid causing high temperature in the sewage discharge pipe and the factory environment. After the process steam enters the steam heat exchange chamber of the air heater, it forms high-temperature condensate. The high-temperature condensate enters the condensate heat exchange chamber of the air preheater through the first drain pipe and the steam trap. After the secondary utilization of the condensate is completed, it converges into the water collection tank through the condensate recovery pipe for the recovery and utilization of the condensate, avoiding the direct discharge of the condensate and causing waste of water resources. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments of the present invention. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to the content of the embodiments of the present invention and these drawings.

[0027] Figure 1 It is a schematic diagram of the steam condensate cooling and recovery energy-saving system of the air heater in tobacco processing in the embodiments of the present invention.

[0028] Reference numerals:

[0029] 100, air heater; 200, preheating unit; 300, recovery unit; 400, process steam delivery pipe; 500, cabinet steam separator;

[0030] 201, air preheater; 202, first drain pipe; 203, steam trap; 204, first stop valve; 205, first filter; 206, first check valve; 207, tee; 208, second drain pipe; 209, condensate discharge valve; 210, second stop valve; 211, second filter; 212, second check valve;

[0031] 301. Condensate recovery pipe; 302. Water collection tank; 303. Drain pipe; 304. Liquid level sensor; 305. Temperature sensor; 306. Condensate recovery electric pump; 307. Control cabinet;

[0032] 401. Vacuum breaking valve; 402. Air vent valve. Specific embodiments

[0033] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention usually described and illustrated in the drawings here can be arranged and designed in various different configurations.

[0034] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of this invention is usually placed during use. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive distinction and cannot be understood as indicating or implying relative importance. In the description of the present invention, unless otherwise stated, the meaning of "a plurality" is two or more.

[0035] In the description of the present invention, it should also be noted that unless otherwise clearly specified and limited, the terms "set" 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. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions from beginning to end. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present invention and cannot be understood as a limitation to the present invention.

[0037] In order to be able to reuse the steam condensate from the air heater, reduce the energy consumption of the air heater, improve the energy-saving efficiency of the cigarette production line, and avoid causing high temperature in the sewage discharge pipeline and the factory environment, this embodiment provides a steam condensate cooling and recovery energy-saving system for an air heater in tobacco processing. The following combinesFigure 1 Describe the specific content of this embodiment in detail.

[0038] Refer to Figure 1 As shown, the steam condensate cooling and recovery energy-saving system for the air heater in tobacco processing in this embodiment includes an air heater 100, a preheating unit 200, and a recovery unit 300. A steam heat exchange chamber and an air conveying channel are provided in the air heater 100, and the process steam in the steam heat exchange chamber is used to heat the air in the air conveying channel. The preheating unit 200 includes an air preheater 201 and a first drain pipe 202. A condensate heat exchange chamber and an air transmission channel are provided in the air preheater 201. The condensate in the condensate heat exchange chamber is used to preheat the air in the air transmission channel. The output end of the air transmission channel of the air preheater 201 is communicated with the input end of the air conveying channel of the air heater 100. One end of the first drain pipe 202 is communicated with the outlet of the steam heat exchange chamber of the air heater 100, and the other end of the first drain pipe 202 is communicated with the inlet of the condensate heat exchange chamber of the air preheater 201. A steam trap 203 is provided on the first drain pipe 202. The recovery unit 300 includes a condensate recovery pipe 301 and a water collection tank 302. One end of the condensate recovery pipe 301 is communicated with the outlet of the condensate heat exchange chamber of the air preheater 201, and the other end of the condensate recovery pipe 301 is communicated with the water collection tank 302.

[0039] Understandably, the steam condensate cooling and recovery energy-saving system of the air heater in tobacco processing constructed in this embodiment is a solution that integrates efficient utilization of thermal energy, recycling of water resources, and environmental protection and energy conservation. The system mainly consists of three major parts: the air heater 100, the preheating unit 200, and the recovery unit 300, forming a complete and closed-loop energy recovery and reuse system. In the core component, the air heater 100, a steam heat exchange chamber and an air delivery channel are provided, and the two achieve efficient energy exchange through the principle of heat conduction. Process steam flows in the steam heat exchange chamber, releasing the latent heat it contains and precisely transferring the heat to the cold air flowing through the air delivery channel, causing the air temperature to rapidly rise to the level required by the process. This process not only ensures strict control of the hot air temperature on the cigarette production line but also lays the foundation for subsequent condensate recovery and reuse through the full release of the steam latent heat. Inside the air preheater 201 of the preheating unit 200, a condensate heat exchange chamber and an air transmission channel are designed, forming a reverse heat exchange mechanism. High-temperature condensate flows out of the steam heat exchange chamber of the air heater 100, is guided by the first drain pipe 202, and enters the condensate heat exchange chamber of the air preheater 201 at a stable and controllable pressure under the precise control of the steam trap 203. At this time, the cold air to be heated first enters the air preheater 201 through the air transmission channel and undergoes indirect heat exchange with the high-temperature condensate, pre-absorbing some of the waste heat in the condensate to achieve preliminary preheating of the air. This design not only effectively reduces the heat load of the air heater 100, reduces energy consumption, but also significantly improves the overall thermal efficiency of the system through the secondary utilization of condensate. More importantly, the introduction of the preheating unit 200 fundamentally solves a series of problems caused by the direct discharge of high-temperature condensate in traditional cigarette production lines. On the one hand, through the reverse heat exchange between the condensate and the cold air, the temperature of the condensate is significantly reduced, avoiding thermal pollution to the sewage pipes and the factory environment during direct discharge and maintaining the comfort and safety of the production environment; on the other hand, when the preheated air enters the air heater 100, it already has a relatively high initial temperature, reducing the demand for process steam by the heater, thereby reducing energy consumption at the source and improving the energy conservation and emission reduction level of the cigarette production line. The recovery unit 300, as the final link of the system, is responsible for the centralized recovery and reuse of the condensate after the secondary heat exchange. After releasing the waste heat in the air preheater 201, the temperature of the condensate further decreases, but it still contains recyclable value. Through the condensate recovery pipe 301, this condensate is safely and efficiently transported to the water collection tank 302, realizing the recycling of water resources. This measure not only effectively reduces water waste during the production process but also reduces the enterprise's wastewater discharge cost through the centralized treatment and reuse of condensate.In summary, the steam condensate cooling and recovery energy-saving system for the air heater in tobacco processing provided by this embodiment realizes the deep excavation and efficient utilization of the waste heat of process steam condensate through the synergistic effect of the preheating unit 200 and the recovery unit 300. It not only significantly reduces the energy consumption of the cigarette production line, improves the thermal efficiency and water resource utilization rate, but also fundamentally solves the environmental and cost problems brought by the discharge of high-temperature condensate.

[0040] Further, a first shut-off valve 204, a first filter 205, a steam trap 203, and a first check valve 206 are sequentially arranged on the first liquid discharge pipeline 202 along its extending direction. The first shut-off valve 204 serves as the "main switch" of the first liquid discharge pipeline 202 and undertakes the safety isolation responsibility during equipment maintenance. During normal system operation, this valve remains fully open to ensure unobstructed flow of condensate in the pipeline; when the equipment is maintained, repaired, or emergently shut down, the operator can quickly close the first shut-off valve 204 to cut off the condensate flow path and prevent the leakage of high-temperature and high-pressure media from causing harm to personnel and equipment. Its reliable sealing performance and fast response characteristics provide a basic guarantee for the safe operation of the system, simplify the equipment maintenance process, and reduce the time cost of shutdown maintenance. The first filter 205 serves as the "purification checkpoint" in the condensate flow path, and its core function is to intercept solid particle impurities such as pipeline rust, welding slag, and scale that may be carried during the condensation of process steam. If these impurities enter the steam trap 203 directly without treatment, they may cause valve core jamming, sealing surface wear, or even blockage, thereby triggering problems such as poor drainage of condensate, accumulation of condensate, or steam leakage, seriously affecting the system thermal efficiency and equipment life. Through a precisely designed filter screen structure, the first filter 205 can efficiently filter particles ≥50 microns in size to ensure that the condensate enters the downstream equipment in a clean state. The detachable filter element design of the first filter 205 facilitates regular cleaning and maintenance, avoids system performance degradation caused by impurity accumulation, and ensures the stable operation and efficient heat exchange of the steam condensate recovery system from the source. The steam trap 203 serves as the "intelligent valve" in the system, and its performance directly determines the timeliness of condensate discharge and the heat energy utilization efficiency. Through the built-in mechanical, thermostatic, or thermodynamic structure, this valve can achieve automatic opening and closing according to the density difference, temperature difference, and pressure difference between condensate and steam: when condensate accumulates, the valve opens; when steam approaches, the valve quickly closes. This opening and closing mechanism not only avoids the ineffective discharge of steam but also ensures the timeliness and thoroughness of condensate discharge, thereby maintaining the optimal heat transfer condition in the steam heat exchange chamber. By precisely controlling the condensate discharge, the steam trap 203 enables the latent heat of process steam to be released more fully, indirectly reducing the steam consumption of the air heater 100 and reducing energy waste and environmental pollution caused by steam leakage. The first check valve 206 serves as the "one-way goalkeeper" at the end of the pipeline, and its core role is to prevent the reverse flow of media that may occur during the condensate recovery process. When the downstream pipeline undergoes pressure transient changes due to pressure fluctuations, pump starts and stops, or valve operations, the valve flap of the first check valve 206 can automatically close to block the reverse flow path of the media, prevent the condensate from flowing back and impacting the steam trap 203 or entering the steam heat exchange chamber, thereby protecting the steam trap 203 from water hammer damage and maintaining the pressure stability of the steam heating system.The synergistic effect of the first cut-off valve 204, the first filter 205, the steam trap 203 and the first check valve 206 enables the first drain pipe 202 to form a complete technical chain from medium control, purification treatment to automatic discharge and anti-backflow protection.

[0041] Further, the preheating unit 200 further includes a three-way pipe 207 and a second drain pipe 208. The first interface of the three-way pipe 207 is communicated with the outlet of the steam heat exchange chamber of the air heater 100, and the second interface of the three-way pipe 207 is communicated with the inlet of the condensate heat exchange chamber of the air preheater 201. One end of the second drain pipe 208 is communicated with the third interface of the three-way pipe 207, and a condensate discharge valve 209 is arranged on the second drain pipe 208. The three-way pipe 207, the second drain pipe 208 and the condensate discharge valve 209 of the preheating unit 200 realize the directional diversion of steam condensate and the control of pollution risk. The first interface of the three-way pipe 207 is directly communicated with the outlet of the steam heat exchange chamber of the air heater 100, and the second interface is connected to the inlet of the condensate heat exchange chamber of the air preheater 201 to form the main condensate water conveying path; the third interface serves as a bypass interface and is connected to the second drain pipe 208 to form an emergency discharge branch. During the operation of the equipment, the process steam enters the air heater 100 to complete air heating and then condenses into high-temperature condensate water, which flows into the three-way pipe 207 through the outlet of the steam heat exchange chamber. Under normal conditions, the condensate water directly enters the air preheater 201 through the first interface → the second interface for waste heat recovery; during the start-up stage, due to the relatively low initial temperature of the steam system, a large amount of low-temperature condensate water is generated in the air heater 100, and impurities remaining in the pipeline or rust products of the initial condensate water may be mixed in this stage, posing a pollution risk. At this time, the following mechanism is used to achieve safe discharge: Emergency discharge control: The condensate discharge valve 209 on the second drain pipe 208 remains open during start-up, so that the possibly contaminated low-temperature condensate water directly drains into the wastewater system through the third interface of the three-way pipe 207; Operating condition switching: After the temperature of the steam system stabilizes, the condensate discharge valve 209 is closed, and the condensate water resumes waste heat recovery through the air preheater 201.

[0042] Further, a second liquid discharge pipeline 208 is successively provided with a second stop valve 210, a second filter 211, a condensate discharge valve 209, and a second check valve 212 along the direction of its own extension. The second liquid discharge pipeline 208 serves as an emergency discharge channel for contaminated condensate during the startup stage. Along the direction of the medium flow, it is successively configured with a second stop valve 210, a second filter 211, a condensate discharge valve 209, and a second check valve 212, forming a four-level technical barrier of "interception - purification - discharge - anti-reverse" to ensure the safety and reliability of the treatment of contaminated condensate. The condensate discharge valve 209 serves as the "total control switch" of the second liquid discharge pipeline 208, undertaking the rapid switching of the discharge path during the startup stage and the system isolation duty during normal operation. Startup stage: At the initial stage of the steam system heating up, the condensate discharge valve 209 automatically opens to provide an independent discharge channel for contaminated and low-temperature condensate; Normal operation: When the internal steam pressure of the heater reaches 0.1 MPa, the condensate discharge valve 209 automatically closes to cut off the waste water discharge path and prevent the loss of heat energy caused by the discharge of qualified condensate; Maintenance: When the equipment is shut down for maintenance, the second stop valve 210 can be separately closed to isolate the second liquid discharge pipeline 208, facilitating the maintenance operations on the downstream condensate discharge valve 209 and the second filter 211. The second filter 211 provides secondary filtration protection against impurities such as pipeline rust, welding slag, and silicate deposits (usually with a particle size > 100 μm) that may be mixed into the condensate during the startup stage, avoiding the entry of impurities into the waste water system or contaminating downstream equipment. The second check valve 212 serves as the "one-way safety valve" of the second liquid discharge pipeline 208 to prevent the reverse flow of the medium caused by pressure fluctuations or siphon effects in the waste water system and ensure the stability of the main system pressure.

[0043] Further, the steam condensate cooling and recovery energy-saving system further includes a process steam delivery pipeline 400. One end of the process steam delivery pipeline 400 is communicated with the inlet of the steam heat exchange chamber of the air heater 100. The process steam delivery pipeline 400 serves as the steam supply artery of the system. One end of it is directly communicated with the inlet of the steam heat exchange chamber of the air heater 100, undertaking the key function of continuously delivering process steam with stable pressure and temperature to the heat exchange chamber. The process steam delivery pipeline 400 serves as the path for steam from the steam source to the air heater 100, ensuring the precise delivery of process steam according to set parameters (such as a pressure of 0.6 MPa - 0.8 MPa and a temperature of 170 °C - 180 °C). Through the stable steam supply of the process steam delivery pipeline 400, the air heater 100 can efficiently transfer the latent heat of the process steam to the air to be heated, which is the starting end of the steam energy release in the condensate cooling and recovery process.

[0044] Furthermore, a vacuum breaker valve 401 and an air vent valve 402 are provided on the process steam transmission pipeline 400. When the condensate drain valve is a pressure control valve, the system pressure is low during startup. At this time, the pressure inside the air heater 100 may be lower than the atmospheric pressure, and the vacuum breaker valve 401 automatically opens to introduce air to break the vacuum, allowing the condensate to be smoothly discharged to the trench through the condensate drain valve 209. After the equipment has been operating for some time, the temperature of the condensate rises, and the pressure inside the air heater 100 also rises accordingly. The condensate drain valve 209 is closed, and the air vent valve 402 is opened to discharge the air inside the system. By adding the vacuum breaker valve 401, it is possible to prevent a vacuum from forming inside the air heater 100 during the startup stage and ensure the normal discharge of condensate. By adding the air vent valve 402, during the steam system heating-up stage, the air accumulated in the pipeline can be discharged in a timely manner to avoid obstruction of steam transmission.

[0045] Furthermore, at least two groups of preheating units 200 are provided. The air preheater 201 of one group of preheating units 200 is used to connect to the condensate from the air heater 100 through the first drain pipe 202, and the air preheater 201 of the other group of preheating units 200 is used to connect to the condensate from the cabinet steam header 500 through the first drain pipe 202. It can be understood that the number of groups of preheating units 200 can be determined according to the actual number of sources of high-temperature condensate, and no excessive restrictions are imposed here.

[0046] Furthermore, the water collection tank 302 is provided with an emptying pipe 303, and the emptying pipe 303 is communicated with the accommodating cavity of the water collection tank 302 to timely discharge the secondary steam that has not been condensed into a liquid state, avoiding the formation of "back pressure" inside the water collection tank 302 and affecting the drainage effect of the steam trap 203.

[0047] Furthermore, the water collection tank 302 is provided with a liquid level sensor 304 and a temperature sensor 305. The condensate recovery unit 300 further includes a condensate recovery electric pump 306, and the outlet of the water collection tank 302 is communicated with the condensate recovery electric pump 306. By adding the liquid level sensor 304, it is used to monitor the liquid level height inside the water collection tank 302 in real time. By adding the temperature sensor 305, it is used to monitor the temperature of the liquid inside the water collection tank 302 in real time. By adding the condensate recovery electric pump 306, it is convenient to quickly discharge the liquid inside the water collection tank 302.

[0048] Further, the recovery unit 300 further includes a control cabinet 307. The condensate recovery electric pump 306, the liquid level sensor 304, and the temperature sensor 305 are all electrically connected to the control cabinet 307. The condensate passing through the air preheater 201 is collected into the water collection tank 302 through the condensate recovery pipe 301. The water collection tank 302 is provided with an exhaust pipe 303 to connect to the atmosphere. At this time, the absolute pressure inside the water collection tank 302 is zero, ensuring that the condensate can be smoothly recovered into the water collection tank 302. The control cabinet 307 collects the signals from the liquid level sensor 304 and the temperature sensor 305, displays the condensate liquid level and temperature in real time, and outputs signals to the condensate recovery electric pump 306 according to the set liquid level parameters to control its start and stop, achieving the purpose of air preheating, condensate and secondary steam cooling, and condensate recovery.

[0049] Note that the above is only the preferred embodiment of the present invention and the technical principles applied. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described here. Various obvious changes, re-adjustments, and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments only. Without departing from the concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. An energy-saving system for cooling and recovering steam condensate in an air heater during tobacco processing, comprising an air heater (100), wherein a steam heat exchange chamber and an air conveying channel are arranged in the air heater (100), and process steam in the steam heat exchange chamber is used to heat air in the air conveying channel, characterized in that, It further includes: A preheating unit (200), including an air preheater (201) and a first drain pipe (202). Inside the air preheater (201), there are a condensate heat exchange chamber and an air transmission channel. The condensate in the condensate heat exchange chamber is used to preheat the air in the air transmission channel. The output end of the air transmission channel of the air preheater (201) is communicated with the input end of the air delivery channel of the air heater (100). One end of the first drain pipe (202) is communicated with the outlet of the steam heat exchange chamber of the air heater (100), and the other end of the first drain pipe (202) is communicated with the inlet of the condensate heat exchange chamber of the air preheater (201). A steam trap (203) is provided on the first drain pipe (202); A recovery unit (300), including a condensate recovery pipe (301) and a water collection tank (302). One end of the condensate recovery pipe (301) is communicated with the outlet of the condensate heat exchange chamber of the air preheater (201), and the other end of the condensate recovery pipe (301) is communicated with the water collection tank (302).

2. The steam condensate cooling, recovery and energy-saving system for the air heater in tobacco processing according to claim 1, wherein On the first drain pipe (202), a first stop valve (204), a first filter (205), the steam trap (203), and a first check valve (206) are sequentially arranged along its own extending direction.

3. The steam condensate cooling and recovery energy-saving system for an air heater in tobacco processing according to claim 1, characterized in that The preheating unit (200) further includes: A tee pipe (207). The first interface of the tee pipe (207) is communicated with the outlet of the steam heat exchange chamber of the air heater (100), and the second interface of the tee pipe (207) is communicated with the inlet of the condensate heat exchange chamber of the air preheater (201); A second drain pipe (208). One end of the second drain pipe (208) is communicated with the third interface of the tee pipe (207), and a condensate discharge valve (209) is provided on the second drain pipe (208).

4. The steam condensate cooling and recovery energy-saving system for the air heater in tobacco processing according to claim 3, characterized in that, On the second drain pipe (208), a second stop valve (210), a second filter (211), the condensate discharge valve (209), and a second check valve (212) are sequentially arranged along its own extending direction.

5. The steam condensate cooling, recovery and energy-saving system for the air heater in tobacco processing according to claim 1, wherein, It further includes a process steam delivery pipe (400). One end of the process steam delivery pipe (400) is communicated with the inlet of the steam heat exchange chamber of the air heater (100).

6. The steam condensate cooling and recovery energy-saving system for the air heater in tobacco processing according to claim 5, characterized in that, A vacuum break valve (401) and an air vent valve (402) are provided on the process steam delivery pipe (400).

7. The steam condensate cooling, recovery and energy-saving system of the air heater in tobacco processing according to claim 1, characterized in that At least two groups of the preheating unit (200) are provided. The air preheater (201) of one group of the preheating unit (200) is used to access the condensate from the air heater (100) through the first drain pipe (202), and the air preheater (201) of the other group of the preheating unit (200) is used to access the condensate from the cabinet steam header (500) through the first drain pipe (202).

8. The steam condensate cooling and recovery energy-saving system for the air heater in tobacco processing according to any one of claims 1-7, characterized in that, The water collection tank (302) is provided with a drain pipe (303), and the drain pipe (303) is communicated with the accommodation cavity of the water collection tank (302).

9. The steam condensate cooling and recovery energy-saving system for an air heater in tobacco processing according to claim 8, characterized in that, The water collection tank (302) is provided with a liquid level sensor (304) and a temperature sensor (305). The recovery unit (300) further includes a condensate recovery electric pump (306), and the outlet of the water collection tank (302) is communicated with the condensate recovery electric pump (306).

10. The steam condensate cooling, recovery and energy-saving system of the air heater in tobacco processing according to claim 9, wherein, The recovery unit (300) further includes: a control cabinet (307), and the condensate recovery electric pump (306), the liquid level sensor (304) and the temperature sensor (305) are all electrically connected to the control cabinet (307).

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