A waste steam and condensate recovery device

Abstract

The present invention relates to a waste steam and condensate recovery device, which adopts a horizontal tank body. The device is composed of a spray system, a waste steam recovery system, a condensate recovery system, and a heat insulation system. The spray system is connected to a cold water interface. Cold water is dispersed into fine water droplets or water streams through the nozzles of the spray system and enters the gas space of the device, then falls onto the liquid surface. The waste steam recovery system is connected to a waste steam interface and is used for cold start-up and long-term operation conditions of the device. The condensate recovery system is connected to a condensate interface. The condensate enters the condensate pipe and is dispersed and ejected through the small holes on the spray pipe, reducing the large impact on the inner wall of the horizontal tank body. The heat insulation system is provided with heat insulation pipelines inside the device, and the device is heat-insulated through a waste steam pipeline. It has high heat exchange efficiency. This device is a hybrid heat exchanger, in which waste steam, condensate and cold water are directly mixed. The system layout is flexible. The horizontal tank body is adopted, which is convenient for layout. It is applicable to various waste steam and condensate parameters, and different systems are set inside the device for different parameter working media.

Description

Technical Field

[0001] The present invention relates to a device for recovering waste steam and drain heat in a power plant. Background Art

[0002] The direct discharge of waste steam and drain water from a power plant into the environment causes waste of water resources and heat. If the waste steam and drain water are recovered, energy waste can be effectively reduced.

[0003] A large amount of waste steam is generated during the operation of deaerators, continuous blowdown flash tanks, and drain flash tanks in power plants. The direct discharge of this part of waste steam into the environment will cause energy loss. Some power plants adopt a mixing type waste steam recovery device, which consists of a steam-water mixer, a deaeration water storage tank, a hot water pump, and a control system. The waste steam is mixed with cold water in a mixing type heat exchanger, enters the deaeration water storage tank to separate non-condensable gases, and is sent to the corresponding application site after being pressurized by the hot water pump. The waste steam working medium and heat energy are completely recovered. [1] Or the waste steam recovery device adopts a surface type heat exchanger, using demineralized water or turbine condensate as the cold source to condense the waste steam, and then enters the drain water tank for recycling. [2]

[0004] Some power plants have installed surface heaters on the demineralized water pipeline, using the waste heat of the continuous blowdown and regular blowdown of the boiler to preheat the demineralized water entering the deaerator, reducing the temperature of the boiler blowdown water, recovering the heat of the drain water, and reducing thermal pollution at the same time. [3] For the recovery of soot blowing drain water, the drain water can be recovered to the heating station, low-pressure heater, or deaerator. A certain power plant adopts a scheme of recovering soot blowing drain water to the deaerator, adding a drain water recovery tank and a control valve in the original system. The soot blowing drain water of the boiler is separated into steam and water in the drain water recovery tank, the steam enters the deaerator, and the condensate water enters the boiler water collection tank. [4]

[0005] Regarding the current waste steam and drain water recovery schemes, most recovery devices adopt different forms of recovery devices for different waste steam and drain water, and the structure is relatively complex. And limited by elements such as structure or volume, it is impossible to recover waste steam and drain water at the same time. If users hope to use waste steam and drain water at the same time to produce hot water for heating with a certain temperature: the requirement for water quality is not too high, and a surface type heat exchanger is not necessary; there are multiple working medium inlets with different parameters, and different systems need to be set to recover working media with different parameters, so a relatively large layout space is required, and vertical equipment is obviously not suitable. Therefore, it is necessary to propose a mixing type heat exchanger device for waste steam and drain water recovery. The device is a horizontal tank body, which can recover waste steam and drain water at the same time and has a certain water storage function. Summary of the Invention

[0006] ​​The present invention provides a device for recovering exhausted steam and condensate. Different systems are set up in the device for media with different parameters. The horizontal tank body is more conducive to the flexible arrangement of interfaces and internal components than the vertical container and also has a water storage function. Therefore, the present invention adopts a horizontal tank body, in which the condensate, exhausted steam and cold water are mixed and heat-exchanged. With this device, the condensate and exhausted steam and their heat can be recovered simultaneously to obtain hot water at a certain temperature.

[0007] To achieve the above object, the technical solution of the present invention is: an exhausted steam and condensate recovery device, which adopts a horizontal tank body. The device is composed of a spray system, an exhausted steam recovery system, a condensate recovery system and a heat preservation system;

[0008] The interfaces arranged on the device are: a cold water interface, a condensate interface, an exhausted steam interface, an exhaust port, a water outlet, a recirculation port, a temperature and liquid level measurement interface, and an overflow port;

[0009] The spray system is connected to the cold water interface. The cold water is dispersed into fine water droplets or water streams through the nozzles of the spray system and enters the gas space of the device, and then falls onto the liquid surface;

[0010] The exhausted steam recovery system is connected to the exhausted steam interface and is used for cold start and long-term operation conditions of the device;

[0011] The condensate recovery system is connected to the condensate interface. The condensate enters the condensate pipe and is dispersed and sprayed out through the small holes on the spray pipe, reducing the large impact on the inner wall of the horizontal tank body;

[0012] For the heat preservation system, heat preservation pipelines are arranged in the device, and the device is heat-preserved through a path of exhausted steam pipeline.

[0013] Furthermore, the spray system is used to reduce the fluctuation of the liquid surface, which is beneficial to the stable operation of the device; at the same time, the steam escaping from the liquid surface is cooled again to further recover heat and working medium.

[0014] Furthermore, the exhausted steam recovery system adopts the exhaust steam of the deaerator to make the steam source continuous and stable.

[0015] Furthermore, the heating devices in the exhausted steam recovery system are symmetrically arranged, which can ensure uniform heating and stable operation of the system; small holes are opened on the bubbling pipes in the exhausted steam recovery system, and the steam is dispersed into many small bubbles and discharged from the small holes, fully heat-exchanging with the cold water, so that the heating steam fully contacts the cold water in the water space.

[0016] Furthermore, the number of heating pipes is determined according to the parameters of the exhausted steam in the heating device to ensure that the steam flow velocity in the pipes of the exhausted steam recovery system is within a reasonable range, and the position of the heating pipes is adjusted according to the arrangement of the internal components in the tank body.

[0017] Furthermore, a protective cover is arranged outside the nozzle in the hydrophobic recovery system, which can prevent small bubbles from eroding the inner wall of the tank and play a protective role.

[0018] Furthermore, the upper, middle, and lower parts of the hydrophobic pipe in the hydrophobic recovery system are all supported: the ring of the upper support is not welded to the pipe; a waist-shaped round hole is fixedly opened on the right side of the middle support steel bar; the lower support uses a support with a semi-circular ring, which provides a certain margin for the vibration amplitude of the hydrophobic pipe, is conducive to the safe fixation of the hydrophobic pipe, and reduces the vibration of the hydrophobic pipe.

[0019] Furthermore, a throttle orifice plate is installed at the inlet of the heat preservation pipeline in the heat preservation system, and the throttle orifice plate selects a throttle orifice plate specification adapted to the heat dissipation situation of the equipment during actual operation.

[0020] Furthermore, the heat preservation pipelines in the heat preservation system are evenly distributed in the equipment, which is conducive to evenly heating the water at various places in the equipment.

[0021] The beneficial effects of the present invention are as follows:

[0022] (1) High heat exchange efficiency. This equipment is a hybrid heat exchanger, and the exhaust steam, hydrophobic water, and cold water are directly mixed.

[0023] (2) Flexible system layout. This equipment adopts a horizontal tank body, which is convenient for layout.

[0024] (3) Applicable to various exhaust steam and hydrophobic parameters. Different systems are set in the equipment for different parameter working media.

[0025] (4) The equipment is equipped with a heat preservation pipe, which can play a role in heating and heat preservation when hot water is not supplied externally, so as to maintain the water temperature in the equipment and shorten the restart time. Description of the Drawings

[0026] Figure 1 is a schematic diagram of the hydrophobic exhaust steam recovery equipment of the present invention;

[0027] Figure 2 is a schematic diagram of the spray system;

[0028] Figure 3 is a schematic diagram of the exhaust steam recovery system;

[0029] Figure 4 is a partial view of the exhaust steam recovery system;

[0030] Figure 5 is a schematic diagram of the hydrophobic recovery system;

[0031] Figure 6 is Figure 5 View B in

[0032] Figure 7 is the front view of the heat preservation system

[0033] Figure 8 is Figure 7 the left view of;

[0034] Figure 9 is Figure 7 the top view of. Detailed implementation manners

[0035] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0036] As Figure 1 shown, a waste steam and condensate recovery device of the present invention uses a horizontal tank body, and the interfaces arranged on the device include: cold water interface, condensate interface, waste steam interface, exhaust port, water outlet, recirculation port, temperature and liquid level measurement interface, overflow port, etc. The device mainly consists of a spraying system, a waste steam recovery system, a condensate recovery system, a heat preservation system, etc.

[0037] The hot water provided by this device is 85°C, and the device is an atmospheric pressure vessel, running safely.

[0038] 1) Spraying system, as Figure 2 shown:

[0039] A spraying device 1 is installed on the upper part of the device. Cold water is dispersed into fine water droplets or water streams through the nozzles of the spraying device 1 and enters the gas space A of the device, and then falls onto the liquid surface. On the one hand, it can reduce the fluctuation of the liquid surface and is beneficial to the stable operation of the device; on the other hand, if there is steam escaping from the liquid surface, it can be cooled again to further recover heat and working medium.

[0040] 2) Waste steam recovery system, as Figure 3 , 4 shown:

[0041] The waste steam of this device is the exhaust steam of the deaerator, and the steam source is continuous and stable. Therefore, the waste steam recovery device is used for cold start and long-term operation conditions of the device. To ensure uniform heating and stable operation of the device, the heating tubes are symmetrically arranged; to make the heating steam fully contact with the cold water in the water space, small holes are opened on the bubbling tube 2, and the steam is dispersed into many small bubbles and discharged from the small holes to fully exchange heat with the cold water. The arrangement of the heating device should determine the number of heating tubes according to the parameters of the waste steam to ensure that the steam flow velocity in the tubes of the waste steam recovery device is within a reasonable range; adjust the position of the heating tubes according to the arrangement of the internal components in the tank.

[0042] 3) Condensate recovery system, as Figure 5 , 6 shown:

[0043] The pressure of soot blowing and draining is relatively high. If no measures are taken for the drain water to enter the tank body, the drain water will quickly vaporize, which may cause a relatively large impact on the inner wall of the tank body and is not conducive to the safety of the equipment. Therefore, an energy dissipation device is adopted in the soot blowing and draining device. As shown in the figure, the drain water enters the drain pipe and is dispersed and ejected through the small holes on the spray pipe 3. A protective cover is arranged outside the spray pipe 3 to prevent the small bubbles from eroding the inner wall of the tank body and play a protective role. In addition, in order to reduce the vibration of the drain pipe, the upper, middle and lower parts of the drain pipe are all supported: the ring of the upper support is not welded to the pipe; a waist-shaped hole is fixedly opened on the right side of the middle support steel bar; the lower support adopts a support with a semi-circular ring, which provides a certain margin for the vibration amplitude of the drain pipe and is conducive to the safe fixation of the drain pipe.

[0044] 4) Thermal insulation system, such as Figure 7 , as shown in Figures 8 and 9:

[0045] Since the equipment does not supply hot water outward at night, but needs to provide hot water at any time the next day, a stream of exhausted steam is retained to enter the equipment for heat preservation. The heat released by the exhausted steam entering the equipment should be equal to the heat dissipated by the equipment to the environment. A throttle orifice plate is installed at the inlet of the heat preservation pipe. The throttle orifice plate has different specifications, and the appropriate throttle orifice plate specification can be selected according to the heat dissipation situation of the equipment during actual operation. The pipelines of the thermal insulation system are evenly distributed inside the equipment, which is conducive to uniformly heating the water at various places inside the equipment.

Claims

1. A waste steam and condensate recovery device, characterized in that: The equipment adopts a horizontal tank body, which is composed of a spray system, a waste steam recovery system, a drain recovery system, and a heat preservation system; The interfaces arranged on the equipment include: cold water interface, drain interface, exhaust steam interface, exhaust port, water outlet, recirculation port, temperature and liquid level measurement interface, and overflow port; The spray system is connected to the cold water interface, and the cold water is dispersed into fine water droplets or water streams through the nozzles of the spray system, enters the air space of the equipment, and falls on the liquid surface; the spray system is used to reduce the fluctuation of the liquid surface, which is conducive to the stable operation of the equipment; at the same time, the steam escaping from the liquid surface is cooled again to further recover heat and working fluid; The exhaust steam recovery system is connected to the exhaust steam interface and is used for cold start and long-term operation of the equipment; the heating device in the exhaust steam recovery system is symmetrically arranged to ensure uniform heating and stable operation of the system; a small hole is opened on the bubbling tube in the exhaust steam recovery system, and the steam is dispersed into many small bubbles and discharged from the small hole to fully exchange heat with the cold water, so that the heating steam is fully in contact with the cold water in the water space; The drain recovery system is connected to the drain interface, and the drain enters the drain pipe and is dispersed and sprayed out through the small holes on the spray pipe, reducing the large impact on the inner wall of the horizontal tank; the upper, middle and lower parts of the drain pipe in the drain recovery system are all supported: the ring of the upper support is not welded to the pipe; the right side of the middle support steel bar is fixed with a waist-shaped hole; the lower support adopts a support with a semicircular ring, which provides a certain margin for the vibration amplitude of the drain pipe, is conducive to the safe fixation of the drain pipe, and reduces the vibration of the drain pipe; The insulation system is provided with an insulation pipeline in the equipment, and the equipment is insulated through an exhaust steam pipeline; a throttling orifice plate is installed at the inlet of the insulation pipeline in the insulation system, and the throttling orifice plate is selected according to the heat dissipation condition of the equipment during actual operation. The number of heating tubes in the heating device is determined according to the parameters of the exhaust steam, so as to ensure that the steam flow rate in the tube of the exhaust steam recovery system is within a reasonable range, and the position of the heating tube is adjusted according to the arrangement of the internal parts of the tank body; A protective cover is arranged outside the spray pipe in the hydrophobic recovery system to prevent small bubbles from eroding the inner wall of the tank body, thus playing a protective role.

2. The waste steam and condensate recovery device according to claim 1, characterized in that: The exhaust steam recovery system uses a deaerator to exhaust steam, so that the steam source is continuous and stable.

3. The exhaust steam and condensate recovery device according to claim 1, characterized in that: The insulation pipelines in the insulation system are evenly distributed in the device, which is conducive to evenly heating the water in various places in the device.

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