Steam absorption and revaporization device

Abstract

The invention relates to the technical field of steam exhaust recycling and reusing and steam compression, in particular to a steam absorbing and revaporizing device which mainly comprises a water pump (1), a two-stage ejector and a steam-water separator (6), and the two-stage ejector is composed of a first ejector (3) and a second ejector (5). The water pump, the steam-water separator and the two-stage ejector are sequentially connected, an outlet of the two-stage ejector is connected with an inlet of the water pump to form a circulating system, the circulating system is provided with a steam suction inlet (4), a steam outlet (6.5) and a bypass pipe (2), one end of the bypass pipe is connected with the outlet of the water pump through a tee joint, and the other end of the bypass pipe is connected with the steam inlet. And the other end of the bypass pipe is connected with one injection inlet of the two-stage ejector. According to the steam pressurization technology, low-temperature and low-pressure steam is firstly mixed into medium-high-pressure circulating water to be liquefied, and then the liquefied steam is vaporized in a steam-water separator.

Description

Technical Field

[0001] The invention relates to the technical field of waste steam recovery and reuse and steam compression, and in particular to a steam absorption and regasification device. Background Art

[0002] The existing steam exhaust steam recovery and reuse equipment mainly includes steam compressors and steam jet pumps. Steam compressors directly use electric motors to drive impellers or screws to directly compress steam. The equipment cost of steam compressors is relatively high. The compression process produces condensed water and superheated steam, which requires water spraying for cooling. In addition, due to the large compression ratio, the temperature rise of one compression is small, and the application range is relatively narrow. Steam jet pumps require a high-pressure steam source, and inject high-pressure steam to inhale low-pressure steam and output medium-pressure steam.

[0003] The steam absorption and revaporization technologies include "a jet steam absorption and revaporization device" with application number 202310491142.1 and "an enhanced jet steam absorption and revaporization device" with application number 202321038896.3. They adopt the concept of mixing steam and liquid first and then vaporizing, using a water vapor ejector to absorb steam, and then vaporizing it using a steam-water separator. These two devices have a common feature: a booster pump is provided at the front end (water inlet end) of the ejector, and the water injected into the ejector is directly pressurized by the booster pump, which is an active boost. This active boosting method is greatly affected by back pressure. In order to offset the influence of back pressure, the jet pressure must be increased or a post-pump must be added, which increases the production cost of the equipment. The emergence of a new technology is always accompanied by the continuous advancement of technology to find a better solution for a technical solution, thereby improving efficiency and reducing costs.

[0004] The purpose of the present invention is to optimize the implementation scheme of the jet steam absorption and revaporization device, solve the adverse effects of the ejector back pressure, and manufacture a jet steam absorption and revaporization device with a post-boosting pump, which forms a negative pressure at the outlet of the ejector and a passive positive pressure at the injection port of the ejector, effectively solving the back pressure problem of the ejector and improving the working efficiency of the machine. The jet steam absorption and revaporization device has a wide range of application prospects and can be used for exhaust steam recovery in power plants, steam heating and pressurization of air-energy steam generators, steam absorption and steam pressurization of evaporators, and the like. Summary of the invention

[0005] The present invention is implemented as follows: a steam absorption and regasification device mainly comprises a water pump (1), a two-stage ejector and a steam-water separator (6), wherein the two-stage ejector is composed of a first ejector (3) and a second ejector (5), and is characterized in that: the outlet of the two-stage ejector is connected to the inlet of the water pump, the outlet of the water pump is connected to the inlet (6.1) of the steam-water separator, the water outlet (6.6) of the steam-water separator is connected to an injection port or an ejection port of the two-stage ejector, forming a circulation system, and the circulation system is provided with a steam suction port (4), a steam outlet (6.5) and a bypass pipe (2), one end of the bypass pipe is connected to the outlet of the water pump, and the other end of the bypass pipe is connected to an injection port of the two-stage ejector.

[0006] There are three connection modes between the main components of the circulation system: a. the water outlet of the steam-water separator is directly connected to the injection port of the second ejector or connected through a pipeline, the outlet of the second ejector is directly connected to the injection port of the first ejector or connected through a pipeline, the outlet of the second ejector is directly connected to the inlet of the water pump or connected through a pipeline, the outlet of the water pump is directly connected to the inlet of the steam-water separator (6.1) through a pipeline, one end of the bypass pipe is connected to the outlet of the water pump through a tee, the other end of the bypass pipe is connected to the injection port of the first ejector, and the steam suction port is connected to the injection port of the second ejector; b. the water outlet of the steam-water separator is directly connected to the injection port of the second ejector or connected through a pipeline, the outlet of the second ejector is directly connected to the injection port of the first ejector or connected through a pipeline, the outlet of the first ejector The inlet of the steam-water separator is directly connected to the inlet of the water pump or connected through a pipeline, the outlet of the water pump is connected to the inlet of the steam-water separator through a pipeline, one end of the bypass pipe is connected to the outlet of the water pump through a tee, the other end of the bypass pipe is connected to the injection port of the second ejector, and the steam suction inlet is connected to the injection port of the first ejector; c. the water outlet of the steam-water separator is directly connected to the injection port of the first ejector or connected through a pipeline, the outlet of the second ejector is directly connected to the injection port of the first ejector or connected through a pipeline, the outlet of the first ejector is directly connected to the inlet of the water pump or connected through a pipeline, the outlet of the water pump is connected to the inlet of the steam-water separator through a pipeline, one end of the bypass pipe is connected to the outlet of the water pump through a tee, the other end of the bypass pipe is connected to the injection port of the second ejector, and the steam suction inlet is connected to the injection port of the second ejector.

[0007] The water pump has one or more, two or more water pumps are arranged in parallel or in series. Two groups of water pumps are arranged in parallel to increase the flow rate or play the role of one for one standby, and two water pumps are connected in series to increase the head or prevent cavitation. Generally, in two water pumps connected in series, the front pump is a low-head pump, and the rear pump is a high-head pump. The low-head pump is to increase the water inlet pressure head for the high-head pump, thereby preventing cavitation from occurring in the high-head water pump. The low-head water pump is a large-flow, low-speed pump with a head of less than 40 meters, and the high-head water pump usually has a head of more than 50 meters. The induction wheel is arranged at the inlet of the water pump, which can also prevent cavitation. The water pump usually uses a high-temperature pump with a temperature resistance of about 180 degrees. Furthermore, two pressure detection units are arranged in the water pump, one of which is arranged at the suction port of the water pump, and the other is arranged at the steam-water separator. By comparing the difference between the signals detected by the two detection units, the cavitation margin is analyzed and transmitted to the control system of the cavitation protection, and the water pump is tripped to enter the control mode of the cavitation protection state.

[0008] The first ejector and the second ejector are both arranged outside the steam-water separator, or the second ejector is arranged outside the steam-water separator and the first ejector is arranged inside the steam-water separator, or the first ejector is arranged outside the steam-water separator and the second ejector is arranged inside the steam-water separator. When the ejector is built inside the steam-water separator, the ejection port of the ejector is the water outlet of the steam-water separator.

[0009] The ejector is provided with an injection inlet, an ejection port and an outlet, and is designed and manufactured according to the Venturi tube principle and the Lafarge nozzle principle. The ejector is divided into a water-steam ejector and a water-water ejector according to its purpose. The injection inlet of the water-steam ejector is filled with water, the ejection port is filled with steam, and the outlet is filled with water or a mixture of steam and water. Usually, 1 cubic meter of water can eject 5 cubic meters of steam. The injection inlet of the water-water ejector is filled with water, the ejection port is filled with water or a mixture of steam and water, and the outlet is filled with water or a mixture of steam and water. The ejector is provided with a contraction section and an expansion section. The fluid will accelerate when entering the contraction section, and will continue to accelerate when entering the expansion section, forming a negative pressure at the ejection port, sucking the fluid at the ejection port in, thereby achieving fluid mixing. The fluid first accelerates in the expansion section and then decelerates, converting kinetic energy into static pressure energy, forming a medium-pressure output at the outlet.

[0010] The first ejector has one or more, two or more first ejectors are connected in parallel, and the first ejector is a single-channel ejector or a multi-channel ejector; the second ejector has one or more, two or more second ejectors are connected in parallel, and the second ejector is a single-channel ejector or a multi-channel ejector. The single-channel ejector has only one injection inlet, one ejection port and one outlet, and the multi-channel ejector is a multi-channel ejector that combines multiple single-channel ejectors into one, in order to increase the mixing flow rate.

[0011] The device is provided with a water supply pipe and / or a drainage pipe, or a water supply-drainage pipe. The water supply pipe is connected to the steam-water separator, or the water supply pipe is connected to the pipeline between the water outlet of the steam-water separator and the inlet of the water pump; the water supply pipe is provided with a water supply joint (9) and a one-way valve (7), and a solenoid valve (8) and / or a water supply pump is provided between the one-way valve and the water supply joint. The one-way valve allows water to flow in from the water supply joint in one direction and prevents water from flowing out from the water supply joint. Before starting the machine, water must be supplied to a specified water level to prevent the water pump from running idle due to lack of water. The machine can be supplied with water by relying on the pressure of tap water or by using a water supply pump. The drainage pipe is provided on the pipeline between the water outlet of the steam-water separator and the inlet of the water pump, and a drainage valve (10) is provided on the drainage pipe; the drainage valve is an electric drainage valve or a manual drainage valve. The drainage pipe is usually connected at the lowest water level. The drainage valve has the functions of draining water and sewage. When the water level in the steam-water separator is too high, the water can be drained through the drain pipe to control the water level. The drain pipe and the water supply pipe are combined into a water supply-drain pipe. The water supply-drain pipe can flow in both directions and does not have a one-way valve. The water supply-drain pipe is generally controlled by an electric valve or a pneumatic valve. The water supply pipe and the drain pipe are often connected to the water outlet of the steam-water separator through a pipe. At this time, the water outlet of the steam-water separator actually has the dual functions of water outlet and water inlet at the same time, that is, the water inlet and outlet of the steam-water separator are combined into one water inlet and outlet.

[0012] The system can output both high-temperature steam and hot water. If hot water is needed, water can be added through the water supply pipe, mixed with steam and discharged through the drain pipe for production and life use. Therefore, the steam absorption and re-vaporization device has the dual functions of steam production and hot water production. The drain valve can also add flow regulation function as needed.

[0013] A filter or a PH neutralizing doser is installed in the steam-water separator or in the pipeline between the water outlet of the steam-water separator and the water pump inlet. The filter and the PH neutralizing doser are optional components. When the incoming steam is chemically contaminated, the filter and the PH neutralizing doser are required to prevent corrosion of the water pump and other components.

[0014] The steam-water separator is provided with a water level detector (6.4) or a mechanical water level controller. The water level detector is fixed on the upper cover (6.2) or the side of the steam-water separator. First, water is replenished into the steam-water separator by a water replenishment pump. When the water level detector detects that the water level has reached a predetermined water level, the water replenishment is stopped. When the water volume is insufficient and reaches the lower limit of the water level, the water is replenished to the predetermined water level again. The water level detector is a water level probe or other types of detectors. The water level detector can detect one water level or multiple water levels at the same time. Preferably, the water level detector is a water level probe. The mechanical water level controller is a float valve type water level controller, which automatically controls the water level of the steam-water separator in a mechanical manner.

[0015] The steam-water separator is provided with one or more inlets, and can support one or more circulating jet injection systems. The inlet of the steam-water separator is connected to the outlet of the water pump through a pipeline.

[0016] The steam-water separator mainly includes a tank body, an inlet (6.1), an upper cover (6.2), a steam outlet (6.5), a water outlet (6.6), and a water inlet. A baffle (6.3) or a spiral blade may be arranged in the tank body as required, or a baffle or a spiral blade may not be arranged. The steam-water separator may be divided into several types according to the type, such as a baffle type, a cyclone type, an adsorption type, and a combined type. The baffle type steam-water separator is relatively simple. High-temperature water is sprayed on the V-shaped slope of the baffle, and the water flow is dispersed and vaporized. The steam passes through the through hole above the baffle, and the unvaporized water falls to the lower part of the steam-water separator. The steam-water separator may also be made into a hollow flash tank, and the steam-water separation is realized by the flash evaporation principle. The water outlet of the steam-water separator may be combined with the water inlet into one water inlet and outlet, which has both the function of water intake and the function of water drainage. When the water level in the steam-water separator is too low and water replenishment is required, water is taken in. When the water level in the steam-water separator is too high, water drainage is required. The inlet of the steam-water separator is arranged on the upper cover of the tank or one side of the upper part of the tank, and the inlet is a jet port, and water is sprayed into the steam-water separator to achieve steam-water separation. The steam outlet is arranged on the upper cover of the tank or one side of the upper part of the tank, and the water outlet is arranged at the bottom.

[0017] The system is equipped with a pressure sensor to control the speed or start and stop of the water pump through changes in pressure.

[0018] A one-way valve is provided on the pipeline between the steam inlet and the ejector port to prevent backflow of water or steam.

[0019] Steam boosting principle: When the water pump is working, positive pressure is generated at the ejector inlet and negative pressure is generated at the ejector outlet. High-speed water flows in from the ejector inlet, generating negative pressure at the ejector outlet to suck in low-pressure steam. The mixture of steam and water is ejected at high speed from the expansion section of the ejector tube, and then gradually decelerates, converting kinetic energy into static pressure energy. The steam is liquefied and becomes medium-pressure hot water, and then sprayed into the steam-water separator through the water pump for steam-water separation. As the steam flow rate of the suction circulation system increases, the pressure in the tank rises accordingly. By adjusting the flow rate of the steam outlet of the steam-water separator, the required medium-pressure steam is obtained, achieving the purpose of first liquefying and then vaporizing the low-pressure steam and boosting the pressure. The steam boosting process is a process of first liquid mixing and then vaporizing.

[0020] During the boosting process, the mechanical energy of the boosting pump will be converted into thermal energy, which can provide part of the thermal energy for steam heating. However, the increase in steam temperature and steam pressure are not completely synchronized. Insufficient heat may cause part of the steam to liquefy more than the steam to vaporize. Therefore, while boosting the pressure, the steam must be heated or part of the condensed water must be discharged to keep the water level in the steam-water separator within the set range.

[0021] A heating device (11) is provided on the pipeline between the water pump outlet and the steam-water separator inlet or in the steam-water separator; the heating device is an electromagnetic heater or an electric heating rod heater. The electromagnetic heater is mainly composed of a circuit board, a coil and a metal tube, and uses the electromagnetic induction principle for indirect heating. The electric heating rod heater is mainly composed of a circuit board and a heating tube, and uses the heating tube to directly heat the hot water.

[0022] The optional accessories at the steam outlet of the steam-water separator include pressure gauge, pressure switch, wafer-type check valve, flange hose, flow regulator, safety valve, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 A schematic diagram of the structure of the first embodiment of the present invention

[0024] Figure 2 A schematic diagram of the structure of the second embodiment of the present invention

[0025] Figure 3 A schematic diagram of the structure of the third embodiment of the present invention

[0026] Figure 4 A schematic diagram of the structure of the fourth embodiment of the present invention

[0027] Figure 5 A schematic diagram of the structure of the fifth embodiment of the present invention DETAILED DESCRIPTION

[0028] The present invention will be further described below in conjunction with the accompanying drawings.

[0029] First embodiment

[0030] See also Figure 1A steam absorption and regasification device mainly comprises a water pump (1), a two-stage ejector and a steam-water separator (6), wherein the two-stage ejector is composed of a first ejector (3) and a second ejector (5). The water pump, the steam-water separator and the two-stage ejector are connected in sequence to form a circulation system, and the circulation system is provided with a steam suction port (4), a steam outlet (6.5) and a bypass pipe (2). The specific connection mode of the circulation system is as follows: the water outlet (6.6) of the steam-water separator is connected to the injection port of the second ejector through a pipeline, the outlet of the second ejector is connected to the injection port of the first ejector through a pipeline, the outlet of the first ejector is connected to the inlet of the water pump through a pipeline, the outlet of the water pump is connected to the inlet (6.1) of the steam-water separator through a pipeline, the steam suction port is connected to the injection port of the second ejector, one end of the bypass pipe is connected to the outlet of the water pump through a tee, and the other end of the bypass pipe is connected to the injection port of the first ejector. The steam outlet is arranged on the side of the upper part of the steam-water separator. A water supply pipe and a drain pipe are connected to the pipeline between the water outlet of the steam-water separator and the injection port of the second ejector. The water supply pipe is provided with a one-way valve (7). A solenoid valve (8) is provided between the water supply joint (9) and the one-way valve. The drain pipe is provided with an electric valve (10). The steam-water separator mainly comprises a tank body, an inlet (6.1), an upper cover (6.2), a baffle (6.3), a water level detector (6.4), a steam outlet (6.5), and a water outlet. The water level probe and the baffle are fixed to the upper cover. In addition to the functions of water discharge and drainage, the water outlet of the steam-water separator also serves as a water supply channel to supply water from the outside to the steam-water separator. However, in order to simplify the description, only the water discharge function is expressed.

[0031] Second embodiment

[0032] See also Figure 2 A steam absorption and regasification device mainly comprises a water pump (1), a two-stage ejector and a steam-water separator (6), and a heater (11), wherein the two-stage ejector is composed of a first ejector (3) and a second ejector (5). The steam-water separator, the second ejector, the first ejector and the water pump are connected in sequence to form a circulation system, and the circulation system is provided with a steam suction port (4), a steam outlet (6.5) and a bypass pipe (2). The water outlet of the steam-water separator is connected to the ejection port of the second ejector through a pipeline, the outlet of the second ejector is connected to the injection port of the first ejector through a pipeline, the outlet of the first ejector is connected to the inlet of the water pump through a pipeline, the outlet of the water pump is connected to the inlet of the steam-water separator through a pipeline, one end of the bypass pipe is connected to the outlet of the water pump through a tee, the other end of the bypass pipe is connected to the injection port of the second ejector, and the steam suction port is connected to the ejection port of the first ejector. The steam outlet is arranged on the side of the upper part of the steam-water separator. The steam-water separator lower part is built with an electric heating rod heater. The remaining undescribed parts are the same as the first embodiment and are not repeated.

[0033] Third embodiment

[0034] See also Figure 3 A steam absorption and re-vaporization device mainly comprises a water pump (1), a two-stage ejector and a steam-water separator (6), wherein the two-stage ejector is composed of a first ejector (3) and a second ejector (5). The steam-water separator, the second ejector, the first ejector and the water pump are connected in sequence to form a circulation system, and the circulation system is provided with a steam suction port (4), a steam outlet (6.5) and a bypass pipe (2). The second ejector is arranged inside the steam-water separator, and the ejection port of the second ejector is also the water outlet of the steam-water separator. The remaining parts not described are the same as those of the second embodiment and will not be repeated.

[0035] Fourth embodiment

[0036] See also Figure 4 A steam absorption and re-vaporization device mainly comprises two water pumps (1), two first ejectors (3), two second ejectors (5), and a steam-water separator (6). A steam-water separator, two parallel second ejectors, two parallel first ejectors, and two parallel water pumps form two parallel circulation systems, each of the two circulation systems is provided with a steam suction port (4) and a bypass pipe (2), and the steam-water separator is provided with two inlets (6.1), a steam outlet (6.5), and a water outlet (6.6). The remaining parts not described are the same as those of the first embodiment and will not be repeated.

[0037] Fifth embodiment

[0038] See also Figure 5 A steam absorption and regasification device mainly comprises a water pump (1), a two-stage ejector and a steam-water separator (6), wherein the two-stage ejector is composed of a first ejector (3) and a second ejector (5). The water pump, the steam-water separator and the two-stage ejector are connected in sequence to form a circulation system, and the circulation system is provided with a steam suction port (4), a steam outlet (6.5) and a bypass pipe (2). The water outlet of the steam-water separator is connected to the ejection port of the first ejector through a pipeline, the outlet of the second ejector is connected to the injection port of the first ejector through a pipeline, the outlet of the first ejector is connected to the inlet of the water pump through a pipeline, the outlet of the water pump is connected to the inlet of the steam-water separator through a pipeline, one end of the bypass pipe is connected to the outlet of the water pump through a tee, the other end of the bypass pipe is connected to the injection port of the second ejector, and the steam suction port is connected to the ejection port of the second ejector. The remaining parts not described are the same as those of the first embodiment and will not be repeated.

Claims

1. A steam absorption and regasification device, mainly comprising a water pump (1), a two-stage ejector and a steam-water separator (6), wherein the two-stage ejector is composed of a first ejector (3) and a second ejector (5), and is characterized in that: The outlet of the double-stage ejector is connected to the inlet of a water pump, the outlet of the water pump is connected to the inlet (6.1) of a steam-water separator, the water outlet (6.6) of the steam-water separator is connected to an ejection port or an ejection port of the double-stage ejector, and a circulation system is formed. The circulation system is provided with a steam suction port (4), a steam outlet (6.5) and a bypass pipe (2), one end of the bypass pipe is connected to the outlet of the water pump, and the other end of the bypass pipe is connected to an ejection port of the double-stage ejector.

2. A steam absorption and regasification device according to claim 1, characterized in that: There are three connection modes between the main components of the circulation system: a. the water outlet of the steam-water separator is directly connected to the injection port of the second ejector or connected through a pipeline, the outlet of the second ejector is directly connected to the injection port of the first ejector or connected through a pipeline, the outlet of the second ejector is directly connected to the inlet of the water pump or connected through a pipeline, the outlet of the water pump is directly connected to the inlet of the steam-water separator (6.1) through a pipeline, one end of the bypass pipe is connected to the outlet of the water pump through a tee, the other end of the bypass pipe is connected to the injection port of the first ejector, and the steam suction port is connected to the injection port of the second ejector; b. the water outlet of the steam-water separator is directly connected to the injection port of the second ejector or connected through a pipeline, the outlet of the second ejector is directly connected to the injection port of the first ejector or connected through a pipeline, the outlet of the first ejector The inlet of the steam-water separator is directly connected to the inlet of the water pump or connected through a pipeline, the outlet of the water pump is connected to the inlet of the steam-water separator through a pipeline, one end of the bypass pipe is connected to the outlet of the water pump through a tee, the other end of the bypass pipe is connected to the injection port of the second ejector, and the steam suction inlet is connected to the injection port of the first ejector; c. the water outlet of the steam-water separator is directly connected to the injection port of the first ejector or connected through a pipeline, the outlet of the second ejector is directly connected to the injection port of the first ejector or connected through a pipeline, the outlet of the first ejector is directly connected to the inlet of the water pump or connected through a pipeline, the outlet of the water pump is connected to the inlet of the steam-water separator through a pipeline, one end of the bypass pipe is connected to the outlet of the water pump through a tee, the other end of the bypass pipe is connected to the injection port of the second ejector, and the steam suction inlet is connected to the injection port of the second ejector.

3. A steam absorption and regasification device according to claim 1, characterized in that: The water pumps may be one or more than one, or two or more than two water pumps may be arranged in parallel or in series.

4. A steam absorption and regasification device according to claim 1, characterized in that: The first ejector and the second ejector are both arranged outside the steam-water separator, or the second ejector is arranged outside the steam-water separator and the first ejector is arranged inside the steam-water separator, or the first ejector is arranged outside the steam-water separator and the second ejector is arranged inside the steam-water separator.

5. A steam absorption and regasification device according to claim 1, characterized in that: The first ejector has one or more, two or more first ejectors connected in parallel, and the first ejector is a single-channel ejector or a multi-channel ejector; the second ejector has one or more, two or more second ejectors connected in parallel, and the second ejector is a single-channel ejector or a multi-channel ejector.

6. A steam absorption and regasification device according to claim 1, characterized in that: The device is provided with a water supply pipe and / or a drainage pipe, or the device is provided with a water supply pipe and a drainage pipe.

7. A steam absorption and regasification device according to claim 1, characterized in that: A heating device (11) is provided on the pipeline between the water pump outlet and the steam-water separator inlet or in the steam-water separator; the heating device is an electromagnetic heater or an electric heating rod heater.

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