Dead steam condensing system of air separation device

Abstract

The utility model relates to the technical field of dead steam condensing, in particular to a dead steam condensing system of an air separation device, which comprises a water cooler and an air extractor. A dead steam inlet branch pipe is arranged at the air inlet end of the water cooler, the air outlet end of the water cooler is communicated with the air extractor through a non-condensable gas exhaust pipe, the output end of the water cooler is communicated with the first condensate pipeline, and the output end of the air extractor is communicated with the second condensate pipeline; the water cooler is additionally arranged, the original dead steam part is conveyed to the water cooler to be condensed, and therefore condensate obtained after the dead steam is condensed is collected through the first condensate pipeline; dead steam which is not fully condensed by the water cooler is subjected to secondary condensation by using the air extractor, and condensate after secondary condensation is collected through the second condensate pipeline, so that on one hand, the overall dead steam condensation effect is improved, condensate water is conveniently recycled, and the working efficiency is improved; on the other hand, dead steam is fully condensed, the dead steam recovery efficiency is improved, and the actual operation requirement is met.

Description

Technical Field

[0001] The utility model relates to the technical field of waste steam condensation, and particularly relates to a waste steam condensation system for an air separation unit. Background Art

[0002] An air separation unit usually adopts a steam turbine for driving. After the steam passes through the steam turbine, waste steam is generated. If the waste steam is directly discharged, it cannot meet the environmental protection requirements. Therefore, the waste steam is usually condensed and then reused.

[0003] The existing waste steam is usually condensed by an air-cooling method. For example, the Chinese patent document with the application number 201220084697.1 provides a direct air-cooled condenser finned tube, which uses the reduction of the air-side resistance to improve the energy-saving requirement.

[0004] However, in summer, the temperature is relatively high, and the condensation effect of the waste steam is poor. Moreover, there are many impurities such as flying fluffs in the external environment, which adhere to the cooling tubes, making the condensation effect even worse. As a result, the waste steam cannot be fully condensed and cannot meet the actual use requirements. Summary of the Utility Model

[0005] The purpose of the utility model is to provide a waste steam condensation system for an air separation unit, so as to solve the technical problem that the current waste steam condensation cannot meet the condensation requirement through air cooling.

[0006] To achieve the above purpose, the utility model provides the following technical solutions:

[0007] A waste steam condensation system for an air separation unit includes a water cooler and an air extractor;

[0008] A waste steam inlet branch pipe is arranged at the air inlet end of the water cooler. The air outlet end of the water cooler is communicated with the air extractor through a non-condensable gas exhaust pipe. The output end of the water cooler is communicated with a first condensate pipeline. The output end of the air extractor is communicated with a second condensate pipeline.

[0009] Further limited, the air extractor includes a starting air extractor and an operating air extractor. The non-condensable gas exhaust pipe is communicated with the starting air extractor through a starting air extractor supply pipe, and the non-condensable gas exhaust pipe is communicated with the operating air extractor through an operating air extractor supply pipe.

[0010] Further limited, an upper water pipe is connected to the upper water end of the water cooler, and a return water pipe is connected to the water outlet end of the water cooler. A communicating pipe is arranged between the upper water pipe and the return water pipe. The communicating pipe is arranged far away from the water cooler, and a communicating valve is arranged on the communicating pipe; the upper water end of the water cooler is located below the water outlet end of the water cooler.

[0011] Further defined, a temperature transmitter and a first pneumatic control valve are provided on the return water pipe. The temperature transmitter is communicatively connected to the first pneumatic control valve, and both the temperature transmitter and the first pneumatic control valve are arranged close to the water cooler; a water supply stop valve is provided on the water supply pipe, and the water supply stop valve is arranged close to the water cooler.

[0012] Further defined, a first instrument air supply pipe is provided on the water supply pipe. The first instrument air supply pipe is located between the water supply stop valve and the water inlet end of the water cooler. A tank internal purge switch valve and a water supply drainage unit are provided on the first instrument air supply pipe. The water supply drainage unit is located between the tank internal purge switch valve and the water supply pipe; a return water drainage unit is provided on the return water pipe, and the return water drainage unit is located between the temperature transmitter and the first pneumatic control valve.

[0013] Further defined, a steam exhaust switch valve and a first instrument air supply pipe are provided on the steam exhaust inlet branch pipe. The steam exhaust venting unit is located between the steam exhaust switch valve and the air inlet end of the water cooler, and a pipe internal purge switch valve is provided on the first instrument air supply pipe.

[0014] Further defined, a liquid level transmitter is provided inside the water cooler, and a second pneumatic control valve is provided on the first condensate pipeline.

[0015] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0016] 1. By adding a water cooler, the present utility model conveys a part of the original steam exhaust to the water cooler for condensation, and then collects the condensate after the steam exhaust condensation through the first condensate pipeline; for the steam exhaust that cannot be fully condensed by the water cooler, an air ejector is used for secondary condensation, and the condensate after the secondary condensation is collected through the second condensate pipeline. On the one hand, it improves the overall steam exhaust condensation effect, facilitates the recovery of condensed water, and improves work efficiency; on the other hand, it fully condenses the steam exhaust, improves the steam exhaust recovery efficiency, and meets the actual operation requirements.

[0017] 2. By providing a temperature transmitter and a first pneumatic control valve on the return water pipe, the present utility model is used to adjust the opening degree of the return water pipe according to the outlet water temperature at the water outlet end of the water cooler, so as to ensure effective condensation of the steam exhaust and improve the condensation efficiency; at the same time, by providing a liquid level transmitter at the output end of the water cooler and a second start control valve on the first condensate pipeline, it is used to adjust the opening degree of the first condensate pipe according to the flow rate of the condensed water.

[0018] 3. The utility model improves the service life of the water cooler by setting a first instrument air supply pipe on the water supply pipe, which is used to dry the inside of the water cooler by using the first instrument air supply pipe when additional auxiliary condensation of the exhaust steam by the water cooler is not required in seasons with relatively low temperatures such as winter. Similarly, a second instrument air supply pipe is set on the exhaust steam inlet branch pipe to dry the inside of the condensation pipe of the water cooler, thereby improving the service life of the water cooler. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the exhaust steam condensation system of the air separation unit of the utility model;

[0020] In the figure: 1 - water cooler; 2 - air extractor; 3 - temperature transmitter; 4 - first pneumatic control valve; 5 - purge switch valve in the tank; 6 - exhaust steam switch valve; 7 - purge switch valve inside the pipe; 8 - second pneumatic control valve; 9 - pressure relief unit; a - exhaust steam inlet branch pipe; b - non-condensable gas exhaust pipe; c - water supply pipe; d - return water pipe; e - first instrument air supply pipe; f - second instrument air supply pipe. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0021] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0022] Embodiment 1

[0023] Refer to Figure 1 , this embodiment provides an exhaust steam condensation system for an air separation unit, which includes the original air cooling island for air cooling the exhaust steam, and also includes a water cooler 1 and an air extractor 2.

[0024] At this time, a part of the exhaust steam output from the steam turbine is input to the air cooling island through the exhaust steam main pipe, and the other part is input to the water cooler 1. The exhaust steam inlet branch pipe a is arranged at the air inlet end of the water cooler 1. The output end of the water cooler 1 is located at the bottom of the water cooler 1. After the exhaust steam is condensed, the condensed liquid is output by relying on its own weight through the output end of the water cooler 1 and collected through the condensate tank. The output end of the water cooler 1 is connected with a first condensate pipeline.

[0025] In order to prevent the water cooler 1 from not being able to fully condense the exhaust steam to generate non-condensable gas, the air outlet end of the water cooler 1 is connected to the non-condensable gas exhaust pipe b to output the non-condensable gas to the air extractor 2. The air extractor 2 is used to perform secondary condensation on the exhaust steam, so that the condensed exhaust steam is output through the second condensate pipeline and collected through the condensate tank, thereby completing the full condensation of the exhaust steam, meeting the actual operation requirements, and improving the exhaust steam condensation efficiency.

[0026] Specifically, the air extractor 2 includes a pneumatic air extractor and an operating air extractor. The non-condensable gas exhaust pipe b is communicated with the corresponding pneumatic air extractor and operating air extractor respectively through the starting air extractor supply pipe and the operating air extractor supply pipe.

[0027] A starting air extractor switch valve is arranged on the starting air extractor supply pipe, an operating air extractor switch valve is arranged on the operating air extractor supply pipe, a non-condensable gas evacuation pipe is arranged on the non-condensable gas exhaust pipe b, and a non-condensable gas drain valve is arranged on the non-condensable gas drain pipe.

[0028] The air extractor 2 is used for the operation of the steam turbine. On the one hand, the non-condensable gas can be condensed by using the air extractor 2 to improve the condensation efficiency of the exhaust steam. On the other hand, the non-condensable gas can be timely extracted by using the air extractor 2 to improve the exhaust efficiency of the non-condensable gas and the condensation efficiency of the exhaust steam.

[0029] Further explanation, the water cooler 1 includes a water cooling tank and water cooling pipes passing through the inside of the water cooling tank. The water cooling pipes are filled with exhaust steam, and the inside of the water cooling tank is filled with cooling water, such as industrial water with a moderate temperature and no corrosiveness in the plant area, which is used for condensing the exhaust steam.

[0030] Specifically, a water inlet end and a water outlet end are arranged on the water cooler 1. The water inlet end is communicated with the water supply pipe c, and the water outlet end is communicated with the return water pipe d.

[0031] Before the operation of the water cooler 1, it is necessary to flush the inside of the water cooling tank. Therefore, it is preferably to arrange a connecting pipe between the water supply pipe c and the return water pipe d, and a connecting valve is arranged on the connecting pipe; so that during operation, the connecting valve is opened to connect the water supply and the return water to realize the circulating flushing of the water cooling tank and the water supply pipe c and the return water pipe d, reduce the consumption of cooling water, and reduce resource waste. The connecting pipe is far away from the water cooler 1.

[0032] After the flushing is completed, the connecting valve is closed to avoid the connection between the water supply pipe c and the return water pipe d and ensure that the water inlet temperature of the cooling water meets the requirements.

[0033] A water supply stop valve is also arranged on the water supply pipe c for closing when the water cooler 1 is not in use; a return water stop valve is also arranged on the return water pipe d. Both the return water stop valve and the water supply stop valve are close to the water cooler 1.

[0034] Preferably, a temperature transmitter 3 and a first pneumatic control valve 4 are also arranged on the return water pipe d. The temperature transmitter 3 is communicatively connected with the first pneumatic control valve 4. The temperature transmitter 3 is close to the water outlet end of the water cooler 1, and the first pneumatic control valve 4 is located between the temperature transmitter 3 and the return water stop valve. According to the return water temperature at the output end of the water cooler 1, the opening of the return water pipe d can be adjusted through the first pneumatic control valve 4, so as to adjust the flow rate of the cooling water and ensure that the exhaust steam can be fully condensed.

[0035] In seasons with relatively low temperatures such as winter, when the air-cooled island can be used to meet the demand for exhaust steam cooling, the flow of cooling water can be shut off through the water supply stop valve and the return water stop valve.

[0036] To ensure that the residual cooling water inside the water cooler 1 will cause damage to the water cooler 1 when the water cooler 1 is out of use, a first instrument air supply pipe e is selected to be arranged on the water supply pipe c, which is used to supply compressed air to dry the inside of the water cooling tank when the water cooler 1 stops working and is closed when the water cooler 1 is working. Therefore, a tank internal purge switch valve 5 is arranged on the first instrument air supply pipe e.

[0037] The first instrument air supply pipe e is located between the water supply stop valve and the water inlet end of the water cooler 1.

[0038] Further explanation, when the water cooler 1 stops operating, it is necessary to drain the internal cooling water. At this time, a water supply drainage unit is arranged on the first instrument air supply pipe e, and a return water drainage unit is arranged on the return water pipe d; the water supply drainage unit is located between the tank internal purge switch valve 5 and the water supply pipe c, and the return water drainage unit is located between the temperature transmitter 3 and the first pneumatic control valve 4.

[0039] Further explanation, to facilitate the control of the opening and closing of the exhaust steam supply, a steam switch valve 6 is selected to be arranged on the exhaust steam inlet branch pipe a.

[0040] Similarly, to avoid the residue of condensate inside the water cooling pipes when the water cooler 1 stops operating, a second instrument air supply pipe f is preferably arranged on the exhaust steam inlet branch pipe a, a pipe internal purge switch valve 7 is arranged on the second instrument air supply pipe f, and the second instrument air supply pipe f is arranged between the air inlet end of the water cooler 1 and the steam switch valve 6.

[0041] Further explanation, to ensure the stable operation of the water cooler 1, a pressure relief unit 9 is selected to be arranged on the water cooler 1. The pressure relief unit 9 is communicated with the cooling pipe and is used to discharge the safety valve in the starting pressure relief unit 9 when the pressure inside the cooling pipe is relatively high.

[0042] To ensure the timely discharge of condensate, a liquid level transmitter is selected to be arranged at the output end of the water cooler 1, a second pneumatic control valve 8 is arranged on the first condensate pipeline, and the liquid level transmitter is communicatively connected with the second pneumatic control valve 8, which is used to increase the opening of the first condensate pipeline of the second pneumatic control valve 8 when there is more condensate to discharge the condensate in a timely manner.

[0043] Obviously, the above-described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0044] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they specify the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0045] It should be noted that the terms "first", "second", etc. in the specification, claims and drawings of the present application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein.

[0046] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An exhaust steam condensation system for an air separation unit, characterized in that: It comprises a water cooler (1) and an air extractor (2); The air inlet end of the water cooler (1) is provided with an exhaust steam inlet branch pipe (a), the air outlet end of the water cooler (1) is connected to the air extractor (2) via a non-condensable gas exhaust pipe (b), the output end of the water cooler (1) is connected to a first condensate pipeline, and the output end of the air extractor (2) is connected to a second condensate pipeline.

2. The exhaust steam condensation system of the air separation unit according to claim 1, characterized in that: The vacuum extractor (2) comprises a starting vacuum extractor and an operating vacuum extractor, the non-condensable gas exhaust pipe (b) is connected to the starting vacuum extractor through an air supply pipe of the starting vacuum extractor, and the non-condensable gas exhaust pipe (b) is connected to the operating vacuum extractor through an air supply pipe of the operating vacuum extractor.

3. The exhaust steam condensation system of the air separation unit according to claim 2, characterized in that: The upper water end of the water cooler (1) is connected to an upper water pipe (c), the water outlet end of the water cooler (1) is connected to a return water pipe (d), a connecting pipe is arranged between the upper water pipe (c) and the return water pipe (d), the connecting pipe is arranged away from the water cooler (1), and a connecting valve is arranged on the connecting pipe; the upper water end of the water cooler (1) is located below the water outlet end of the water cooler (1).

4. The exhaust steam condensation system of the air separation unit according to claim 3, characterized in that: The return water pipe (d) is provided with a temperature transmitter (3) and a first pneumatic control valve (4), the temperature transmitter (3) is in communication connection with the first pneumatic control valve (4), and the temperature transmitter (3) and the first pneumatic control valve (4) are both arranged close to the water cooler (1); the water supply pipe (c) is provided with a water supply stop valve, and the water supply stop valve is arranged close to the water cooler (1).

5. The exhaust steam condensation system of the air separation unit according to claim 4, characterized in that: The water supply pipe (c) is provided with a first instrument gas supply pipe (e), the first instrument gas supply pipe (e) is located between the water supply stop valve and the water supply end of the water cooler (1), the first instrument gas supply pipe (e) is provided with a tank purge switch valve (5) and a water supply and drainage unit, the water supply and drainage unit is located between the tank purge switch valve (5) and the water supply pipe (c); the return water pipe (d) is provided with a return water drainage unit, the return water drainage unit is located between the temperature transmitter (3) and the first pneumatic control valve (4).

6. The exhaust steam condensation system of the air separation unit according to claim 5, characterized in that: The exhaust steam inlet branch pipe (a) is provided with an exhaust steam switch valve (6) and a second instrument gas supply pipe (f); the second instrument gas supply pipe (f) is arranged between the air inlet end of the water cooler (1) and the exhaust steam switch valve (6); and the second instrument gas supply pipe (f) is provided with an in-pipe purge switch valve (7).

7. The exhaust steam condensation system of the air separation unit according to claim 6, characterized in that: A liquid level transmitter is arranged in the water cooler (1), a second pneumatic control valve (8) is arranged on the first condensate pipeline, and the liquid level transmitter is communicatively connected with the second pneumatic control valve (8).

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