WO2018119991A1

WO2018119991A1 - Online temperature monitoring system and method for direct air-cooled condenser

Info

Publication number: WO2018119991A1
Application number: PCT/CN2016/113394
Authority: WO
Inventors: 郭汉森; 段媛媛
Original assignee: 乔治洛德方法研究和开发液化空气有限公司; 郭汉森; 段媛媛
Priority date: 2016-12-30
Filing date: 2016-12-30
Publication date: 2018-07-05
Also published as: CA3049311C; CN110088552A; CA3049311A1; AU2016434590A1; US20190346207A1; AU2016434590B2; CN110088552B

Abstract

An online temperature monitoring system and method for direct air-cooled condenser. The system comprises: a temperature sensor moving system provided above a heat exchange tube bundle surface (2) of a direct air-cooled condenser; a temperature sensor (1) is mounted on the temperature sensor moving system; the temperature sensing moving system moves the temperature sensor (1) on a plane parallel to the heat exchange tube bundle surface (2) of the direct air-cooled condenser; data collected by the temperature sensor (1) is uploaded to a data processing system (5) connected to the temperature sensor; the data processing system (5) can implement the functions of collecting, analyzing, storing, and querying the data, and giving an alarm according to pre-settings. Compared with the arrangement of multiple monitoring cables in the prior art, the system and method can implement multipoint scanning, simplifies wiring, avoids a detection dead zone, and has flexibility.

Description

Direct air condenser temperature online monitoring system and method

[0001] The present invention relates to a direct air-cooled condenser temperature on-line monitoring system and method, and more particularly to a mobile direct air condenser temperature online monitoring system and method.

Background technique

[0002] The function of a direct air condenser is to condense the low pressure steam discharged from the turbine to become condensed water. The direct air condenser is mainly composed of an axial fan system, an A-frame support system, a condensate system, a drain system, a bundle system, an evacuation system and a cleaning system. The tube bundle is made up of a heat exchange tube composed of a steel base tube and external fins, arranged in a regular pattern and welded to the tube sheet at both ends. The base pipe has a circular, elliptical or oblate cross section. The fins are galvanized in aluminum or steel and are attached to the base pipe by winding, nesting, brazing or extrusion. The steam and the air are directly subjected to surface heat exchange through the metal fin heat exchange tubes, and the heat exchange tubes are low-pressure steam, and the heat exchange tubes are outside the atmosphere. According to the arrangement of the heat exchange tubes, it can be divided into single row tube, double row tube, three row tube and four row tube (MASH) system. When the ambient temperature is below zero. In the case of C, because the heat load of the heat exchange tube is too small or unevenly distributed, and the presence of non-condensable gas, the heat exchange tube bundle is usually easily blocked or frozen during the startup of the equipment and at a lower load, and the tube bundle is severely damaged. Deformation of the condensate pipe and cracking of the pipe caused the equipment to be shut down. Therefore, it is necessary to monitor the temperature of the direct air condenser in the winter. It is also possible to understand the operating status of the direct air condenser and adjust the axial fan accordingly.

[0003] At present, the temperature measurement of the direct air condenser heat exchanger tube bundle usually adopts the following solutions: 1) dispatching personnel to carry out manual inspection, but the working environment of manual inspection is bad, labor intensity is large, and most importantly, Manual inspection can not achieve real monitoring, staff can not be adjusted according to site conditions; 2) CN205537182U provides an in-line air condenser temperature field online monitoring system, including multiple monitoring cables, multiple a collector, a communication cable, and a main control unit, wherein one or more of the plurality of monitoring cables are electrically connected to one of the plurality of collectors, respectively, and the collectors are respectively connected through the communication cable Master control electromechanical connection. A plurality of monitoring cables are disposed outside the heat exchange tube bundle, and the temperature field is monitored online by using a digital temperature sensor, but the system includes multiple monitoring cables and multiple Collector and communication cable, installation and maintenance cost is high, not only the calibration fee is laborious, but once the temperature sensor fails, the replacement is more troublesome; in addition, the cable wiring has higher space requirements, and the heat transfer effect is not removed in summer. Also has an effect; the temperature collection point is fixed, there will be detection of dead angles, no flexibility technical problems

[0004] The object of the present invention is to overcome the deficiencies of the prior art, and to provide a direct air condenser temperature online monitoring system and method, and more particularly, a mobile direct air condenser temperature online monitoring system And methods.

Problem solution

Technical solution

In accordance with one aspect of the invention, a direct air condensate temperature on-line monitoring system is provided.

[0006] The direct air condenser temperature online monitoring system according to the present invention comprises: a temperature sensor, a temperature sensor moving system and a data processing system, wherein: the temperature sensor moving system makes the temperature sensor parallel to the direct air condenser The heat transfer tube bundle moves on the surface of the beam.

[0007] wherein, the route moved by the temperature sensor moving system and the area scanned by the temperature sensor are preset according to different arrangement forms of the direct air condenser heat exchange tubes.

[0008] The data processing system is connected to the temperature sensor, and is used for collecting, analyzing, storing, querying, and alarming the data collected by the temperature sensor according to a preset setting.

[0009] Advantageously, multiple mode controls are implemented in accordance with the field configuration.

[0010] Advantageously, the temperature sensor movement system comprises a nozzle assembly of a direct air condenser cleaning system.

[0011] Advantageously, the temperature sensor is an infrared thermometer.

[0012] Advantageously, different specifications of the infrared thermometer are selected according to the environmental conditions of the site.

[0013] Advantageously, the temperature sensor is fitted with a universal joint.

[0014] Advantageously, the temperature sensor is perpendicular to the surface of the heat exchange tube bundle of the direct air condenser.

[0015] According to another aspect of the invention, an on-line monitoring method for direct air condenser temperature is provided.

[0016] The method for online monitoring of direct air condenser temperature according to the present invention, comprising: providing a temperature sensor moving system above a surface of a heat exchange tube bundle of a direct air condenser, and installing on the temperature sensor moving system a temperature sensor and on the surface of the heat exchange tube bundle parallel to the direct air condenser Moving on the plane; uploading the data collected by the temperature sensor to the connected data processing system, the system can realize the function of collecting, analyzing, storing, querying and alarming according to the preset setting.

[0017] According to another aspect of the present invention, there is also provided an application of a nozzle assembly of a direct air condenser cleaning system as part of a temperature sensor movement system, characterized in that: the temperature sensor movement system is direct A portion of an on-line monitoring system for an air condenser temperature, the system further comprising a temperature sensor and a data processing system, wherein at least one temperature sensor is mounted on the nozzle assembly of the direct air condenser cleaning system and is subsequently parallel The plane of the heat exchange tube bundle surface of the direct air condenser moves.

Advantageous effects of the invention

Beneficial effect

[0018] The beneficial effects of the present invention over the prior art are as follows:

[0019] 1. Through the on-line monitoring system of the direct air condenser temperature of the present invention, it is possible to advantageously and continuously measure the temperature of the area where the direct air condenser is likely to freeze.

[0020] 2. Compared with a plurality of monitoring cable arrangements, the present invention can realize multi-point scanning, simplifies wiring, and does not detect dead spots, and has flexibility.

[0021] 3. According to the present invention, the route of the movement of the temperature sensor moving system and the area scanned by the temperature sensor can be preset by the programmable controller according to different arrangement forms of the heat exchange tubes of the direct air condenser.

[0022] 4. The present invention can perform off-line configuration and configuration work on the programmable controller, thereby realizing the adjustment of the moving route of the temperature sensor moving system and the scanning area of the temperature sensor according to the special requirements of the user, and implementing multiple mode control.

[0023] 5. The invention fully utilizes the basic configuration of the cleaning system, does not require new equipment investment, and is easy to be upgraded in the existing direct air condenser system, which makes installation convenient, saves work, and reduces cost.

Brief description of the drawing

DRAWINGS

[0024] Embodiments of the invention will be further described below with reference to the accompanying drawings in which:

1 is a schematic diagram showing the connection of various components of a direct air-cooling condenser temperature online monitoring system according to the present invention. Preferably, the nozzle assembly of the direct air condenser cleaning system is used as a part of a temperature sensor moving system. Minute;

2 is a pre-set flow path of a temperature sensor moving system and a region scanned by a temperature sensor in a four-row tube (MASH) system according to the present invention;

[0027] FIG. 3 is a schematic diagram of a moving path of a temperature sensor and a temperature sensor in a single-row, double-row or three-row system of the present invention.

Embodiments of the invention

[0028] "Temperature sensor" refers to a sensor that senses temperature and converts it into an available output signal. The temperature sensor is the core of the temperature measuring instrument and has a wide variety. According to the measurement method, it can be divided into two types: contact type and non-contact type. The non-contact temperature sensor does not need to be in contact with the measured medium, but is transmitted to the temperature sensor through the heat radiation or convection of the measured medium to achieve the purpose of temperature measurement. This type of sensor mainly has an infrared thermometer. The environmental conditions in which the infrared thermometer is located, such as temperature, dust, smoke and steam conditions, have an impact on the selected specifications and measurement accuracy.

[0029] "Temperature sensor moving system" refers to a system that is mounted above the surface of a direct air condenser A-frame heat exchange tube bundle and that moves in a plane parallel to the surface of the heat exchange tube bundle of the direct air condenser, such as The nozzle assembly of the direct air condenser cleaning system.

[0030] A "data processing system" refers to a system constructed by processing information using a computer. Through the data processing system, the data information is processed and sorted, various analysis indexes are calculated, and the information forms that are easily accepted by people are converted, and the processed information can be stored. The DCS distributed control system is usually adopted, and it is also called the distributed control system in the self-control industry. It is a multi-level computer system composed of process control level and process monitoring level, which is a communication network. It integrates 4C technologies such as computer, communication, display and control. Its basic idea is decentralized control, centralized operation, hierarchical management, Flexible configuration and easy configuration. Thereby, the function of collecting, analyzing, storing, and arranging the data collected by the temperature sensor according to the present invention and alarming according to the preset setting can be realized.

[0031] According to different arrangement forms of direct air condenser heat exchanger tubes, it can be divided into single row tube, double row tube, three row tube and four row tube (MASH) system, and the arrangement form of the heat exchange tube determines the temperature sensor movement. The system moves the route and the area scanned by the temperature sensor.

[0032] The direct air condenser heat exchange tube is divided into a downstream tube and a counter flow tube, and the steam and condensate flow inside the heat exchange tube To the same downstream pipe, the opposite direction of steam and condensate flow is the counterflow tube. Most of the steam condenses in the downstream pipe, and the steam in the countercurrent bundle condenses through the reverse flow, that is: the remaining steam and the non-condensable gas flow from the bottom to the top in the counterflow tube, and some condensed water is still generated and flows downward in the process. The cis and counterflow pipes are connected through the bottom condensate tank to balance the pressure measured on both sides and the steam water. The air pipe bundle is arranged at the top of the counterflow pipe to extract the non-condensed gas and maintain the vacuum state inside the air condenser. The downstream pipe and the counterflow pipe may be arranged separately or in a mixed arrangement.

[0033] According to the arrangement of the cis and counterflow tubes, there are four types: one is a four-row tube (MASH) system, consisting of three rows of downstream tubes close to the A-type support frame and the outermost one row of counter-flow tubes; Second, large-diameter flat steel brazed aluminum serpentine finned tubes or hot-dip galvanized steel fins on flat steel tubes, single-row tube arrangement; third, hot-dip galvanized large-diameter elliptical steel tube sets of rectangular steel fins, double-row tube arrangement The fourth is a large-diameter hot-dip galvanized elliptical steel tube around an elliptical finned tube, three rows of tubes.

[0034] In the above four arrangements, the single-row tube, the double-row tube and the three-row tube system belong to the case where the downstream tube and the counter-current tube are separately arranged, that is, the downstream tube and the counter-current tube are distributed in the whole piece. Different areas of the surface of the heat pipe bundle; the four-row tube (MASH) system is a mixture of the downstream pipe and the counter-flow pipe, that is, the three rows of downstream pipes close to the A-type support frame and the outermost row The counterflow tubes are arranged across the surface of the entire heat exchange tube bundle. In the winter, since the steam flow in the downstream pipe is relatively sufficient, the subsequent counter-flow pipe steam is less, which causes the counter-current pipe bundle to be easily frozen. Therefore, in the present invention, the counter-current pipe is mainly required for temperature online monitoring. For single-row, double-row and three-row systems, the counterflow tube is placed separately in the partial heat exchange tube bundle area (Fig. 3), and the four-row tube (MASH) system counterflow tube is arranged in the entire heat exchange tube bundle area (Fig. 2) , so the area scanned by the temperature sensor will be different. In other words, the route of the movement of the temperature sensor moving system and the area scanned by the temperature sensor can be preset by the programmable controller according to the different arrangement of the heat exchange tubes.

[0035] Furthermore, for the above four arrangements, the base pipes are evenly spaced in a direction extending along the A-type support frame. In order to ensure that each column of the tube in the scanning area required for the surface of the heat exchange tube bundle is scanned, the pitch at which the temperature sensor moving system is moved is set in advance as the pitch of the base tube. The spacing of the base tubes varies with the arrangement of the heat exchange tubes.

[0036] "Multiple mode control according to field configuration" refers to offline configuration and configuration of the programmable controller, thereby realizing the adjustment of the movement path of the temperature sensor mobile system according to the special requirements of the user. The area scanned by the temperature sensor enables multiple modes of control. For example, a single-row, double-row or three-row system can be scanned across the entire heat transfer tube beam plane according to customer requirements.

[0037] After the heat exchange tube bundle of the direct air condenser is operated for a period of time, a dust deposit with strong adhesion is generated on the surface of the fin, which weakens the heat exchange capacity of the tube bundle and directly affects the operation of the steam turbine unit. Therefore, the heat exchange tube bundle must be cleaned regularly, so the cleaning system becomes the basic configuration of the air condenser, and the heat exchange tube bundle is washed by the pressure water sprayed from the nozzle on the nozzle assembly of the cleaning system.

[0038] When the ambient temperature in winter is lower than 0 ° C, the heat exchanger tube bundle of the condenser is extremely likely to freeze, and the cleaning system does not work, and the solution can just play the nozzle assembly of the cleaning system parallel to the direct air condenser. The characteristic of the movement of the tube bundle surface in the plane, the temperature sensor is mounted on the nozzle assembly, thereby realizing the function of the temperature sensor moving and collecting data in a plane parallel to the surface of the tube bundle of the direct air condenser.

1 is a schematic diagram showing the connection of various components of a direct air condenser temperature online monitoring system. Preferably, the nozzle assembly of the direct air condenser cleaning system is used as part of a temperature sensor moving system. As shown in Fig. 1, in order to realize the movement of the temperature sensor 1 in a plane parallel to the surface 2 of the heat exchange tube bundle of the direct air condenser, the temperature sensor 1 is mounted on the nozzle assembly 4 of the direct air condenser cleaning system 3, data The processing system 5 is coupled to the temperature sensor 1 for collecting, analyzing, storing, querying, and alerting the data collected by the temperature sensor according to a predetermined setting. The cleaning system 3 has upper and lower lateral rails 6, and a moving cleaning platform 7 is provided between the upper and lower transverse rails 6. The mobile washing platform 7 is driven by a horizontal drive mechanism disposed at the top to laterally move between the upper and lower transverse guides 6; the upper and lower transverse guides 6 are in a plane parallel to the surface 2 of the heat exchange tube bundle of the direct air condenser The mobile cleaning platform 7 is fixed with a longitudinal rail 8 on a side of the relatively direct air condenser; the nozzle assembly 4 is disposed on the mobile cleaning platform 7 and is driven by a lifting drive mechanism disposed on the cleaning system 3; The left and right stop points of one of the lower rails 6 corresponding to the movement of the moving cleaning platform 7 are respectively provided with a stroke switch 9; the upper and lower dead points corresponding to the movement of the nozzle assembly 4 on the longitudinal rail 8 are respectively provided with a stroke 幵Off 10. The lateral movement of the mobile washing platform 7 and the longitudinal movement of the nozzle assembly 4 are controlled by a programmable controller. Each of the above components is mounted on the A-type support frame 11

Embodiment 1

[0041] FIG. 2 is a four-row tube (MASH) system preset temperature sensor moving system movement route and temperature The area scanned by the sensor. In the process of starting the device and at a lower load, in order to shorten the scanning period, the area can be defined as a plane area where the bottom of the heat exchange tube bundle traverses the entire tube beam plane and moves up and down by a height of 1 m, because the air flow through this area is large, Walking more heat, the most likely to freeze. The scanning area and path are as shown in Fig. 12, wherein the spacing of the base tubes is A.

[0042] In the programmable controller system, the button and the stroke are used as the input signal components of the programmable controller, and the contactor is used as the output actuator, and the horizontal drive mechanism for controlling the lateral movement and the elevation drive mechanism for the longitudinal movement are rotated forward. , reverse, stop, and run. The mobile cleaning platform is operated until the left and right stop points touch the stroke switch 9, and the upper and lower dead points touch the stroke switch 10, which can automatically stop.

[0043] After the fully automatic control operation starts, adjust the position of the mobile cleaning platform so that the temperature sensor is directly above the center line of the rightmost base pipe, the nozzle assembly is at the bottom dead center position, and then the nozzle assembly is up 1000 mm - the moving cleaning platform is moved to the left 95mm, where the spacing A of the four rows of pipe base pipes is 95mm; then the nozzle assembly descends 1000mm - the moving cleaning platform moves 95mm to the left, repeating until the moving cleaning platform moves to the left stop position and returns to the original position. Scan it in about 10 minutes. During the operation, if you want to stop working, you can press the "pause" button to choose to maintain the existing position or return to the original position.

Embodiment 2

[0045] FIG. 3 is a region in which a single-row tube, a double-row tube, or a three-row tube system is pre-set by a temperature sensor moving system to move the route and temperature sensor. Because for single-row, double-row, and three-row systems, the counterflow tube is separately disposed in a portion of the heat exchange tube bundle, and only the area where the countercurrent tube bundle is separately disposed can be scanned. In order to shorten the scanning period during the startup of the device and after the load is low, it can be limited to a plane area with a height of 1 m along the bottom of the countercurrent tube bundle. The scanning area and path are as shown in Figure 13, where the spacing of the base tubes is B.

[0046] After the fully automatic control operation starts, adjust the position of the mobile cleaning platform so that the temperature sensor is directly above the center line of the rightmost base pipe, the nozzle assembly is at the bottom dead center position, and then the nozzle assembly is up 1000 mm - the moving cleaning platform is shifted to the left. 58mm, here is a single row of tubes, the spacing B of the base pipe is 58mm; then the nozzle assembly is down 1000mm - the moving cleaning platform is moved 58mm to the left, repeating until the moving cleaning platform moves to the left stop position and returns to the original position. Scan it in about 5 minutes. During the operation, if you want to stop working manually, you can press the "Pause" button to choose to maintain the existing position or return to the original position.

[0047] As another embodiment, the programmable controller is configured and configured offline to implement the root According to the special requirements of the user, adjust the path of the temperature sensor moving system and the area scanned by the temperature sensor. For example, a single-row, double-row or three-row system can be scanned across the entire heat transfer tube beam plane according to customer requirements.

[0048] For the above embodiment, when the collected temperature is lower than 20 ° C, an alarm is triggered, and the data processing system records the first out of the system. The first out refers to the first alarm signal that occurs after an accidental trip. This signal is very important for the analysis of the cause of the accident. Basically, it can be considered as the main cause of equipment protection actions. Therefore, the operating state of the air-cooled condenser is known, and the axial fan is adjusted accordingly.

[0049] The above description of the present invention is exemplified by the use of a nozzle assembly of a direct air condenser cleaning system as part of a temperature sensor movement system, but those skilled in the art will appreciate that the present invention is also applicable to In addition to any obvious modifications made on the premise of the inventive concept, an additional set of temperature sensor movement systems is added to achieve the function of the temperature sensor moving in a plane parallel to the tube bundle surface of the direct air condenser.

Claims

Claim

[Claim 1] An on-line monitoring system for direct air condenser temperature, comprising a temperature sensor, a temperature sensor moving system and a data processing system, characterized in that: the temperature sensor moving system makes the temperature sensor parallel to the direct air condenser The surface of the heat exchange tube bundle moves in a plane.

[Claim 2] The direct air condenser temperature online monitoring system according to claim 1, wherein: the temperature sensor moves the moving route of the system and the area scanned by the temperature sensor, according to the direct air condenser heat exchanger Different arrangements of tubes are preset.

[Claim 3] The direct air condenser temperature online monitoring system according to claim 1, wherein: the data processing system is connected to a temperature sensor for collecting, analyzing, and collecting data collected by the temperature sensor. Store, query and alert based on pre-set settings.

[Claim 4] The direct air condenser temperature online monitoring system according to claim 2, wherein: a plurality of mode controls are implemented according to the site configuration.

[Claim 5] The direct air condenser temperature online monitoring system according to claim 1 or 2, wherein: the temperature sensor moving system comprises a nozzle assembly of a direct air condenser cleaning system.

[Claim 6] The direct air condenser temperature online monitoring system according to claim 1, wherein: the temperature sensor is an infrared thermometer.

[Claim 7] The direct air condenser temperature online monitoring system according to claim 6, wherein: an infrared thermometer of different specifications is selected according to environmental conditions on the site.

[Claim 8] The direct air condenser temperature online monitoring system according to claim 7, wherein: the temperature sensor is mounted with a universal joint.

[Claim 9] The direct air condenser temperature online monitoring system according to claim 8, wherein: the temperature sensor is perpendicular to a surface of the heat exchange tube bundle of the direct air condenser.

[Claim 10] A method for online monitoring of direct air condenser temperature, characterized in that it comprises:

a temperature sensor moving system is disposed above the surface of the heat exchange tube bundle of the direct air condenser, a temperature sensor is mounted on the temperature sensor moving system, and moves on a plane parallel to the surface of the heat exchange tube bundle of the direct air condenser;

Uploading data collected by the temperature sensor to a connected data processing system, the system The ability to collect, analyze, store, query, and alert based on pre-set data.

[Claim 11] The method for online monitoring of direct air condenser temperature according to claim 10, wherein: the path of the temperature sensor moving system and the area scanned by the temperature sensor are different according to the direct air condenser heat exchanger tube. The arrangement is preset.

[Claim 12] The method for online monitoring of direct air condenser temperature according to claim 11, characterized in that: a plurality of mode control is implemented according to the field configuration.

[Claim 13] The direct air condenser temperature on-line monitoring method according to claim 10 or 11, wherein: the temperature sensor moving system comprises a nozzle assembly of a direct air condenser cleaning system.

[Claim 14] The method for online monitoring of direct air condenser temperature according to claim 10, wherein: the temperature sensor is an infrared thermometer.

[Claim 15] The method for online monitoring of direct air condenser temperature according to claim 14, characterized in that: an infrared thermometer of different specifications is selected according to environmental conditions on the site.

[Claim 16] The method for online monitoring of direct air condenser temperature according to claim 15, wherein: the temperature sensor is mounted with a universal joint.

[Claim 17] The method for online monitoring of direct air condenser temperature according to claim 16, wherein: the temperature sensor is perpendicular to a surface of the heat exchange tube bundle of the direct air condenser.

[Application 18] An application for using a nozzle assembly of a direct air condenser cleaning system as part of a temperature sensor movement system, wherein: the temperature sensor movement system is a direct air condenser temperature online monitoring system In part, the system further includes a temperature sensor and a data processing system, wherein at least one temperature sensor is mounted on the nozzle assembly of the direct air condenser cleaning system, and then in the heat exchange tube bundle parallel to the direct air condenser The surface moves on the plane.