CN116465681A - Water vapor centralized sampling system and method - Google Patents

Abstract

The invention discloses a water vapor centralized sampling system and method, comprising several sampling subsystems; the inlet ports of the several sampling subsystems are respectively connected with the corresponding sampling ports in the water vapor system, and the outlet ports are respectively connected with online chemical instruments; the sampling subsystem includes a stop valve, a cooler, an electric pressure regulating valve, a constant temperature device and an electric flow regulating valve sequentially arranged on the sampling pipeline; a sewage outlet is arranged on the sampling pipeline; The electric sewage valve, the electric pressure regulating valve and the electric flow regulating valve are all connected to each other to realize the automatic operation control of the electric sewage valve, the electric pressure regulating valve and the electric flow regulating valve; the invention realizes regular automatic sewage discharge, automatic pressure regulation and automatic flow adjustment, so as to ensure that the water/steam samples entering the online chemical instrument are representative of sampling, and the parameters of each water/steam sample meet the measurement requirements of the on-line chemical instrument.

Description

A centralized water vapor sampling system and method

technical field

The invention belongs to the technical field of water vapor system sampling, in particular to a water vapor centralized sampling system and method.

Background technique

Thermal power plants in the traditional electric power industry and oil refineries in the petrochemical industry have long-standing and ubiquitous problems such as "water samples are easily polluted, the iron content of corrosion impurities is not representative, the temperature of instrument water samples exceeds the standard, and the pressure and flow instability affect instrument measurement".

At present, thermal power plants and petrochemical enterprises usually use a concentrated water vapor sampling device to sample the water vapor in operation, and send it to the online chemical instrument for inspection after cooling and pressure reduction; however, due to the lack of sewage discharge measures, it is difficult to discharge corrosion debris in a timely and effective manner; in addition, the lack of effective pressure and flow adjustment methods makes the online chemical instrument measurement unstable, which has a huge impact on the safe operation of the unit.

Contents of the invention

Aiming at the technical problems existing in the prior art, the present invention provides a centralized water vapor sampling system and method to solve the technical problems that the existing concentrated water vapor sampling device is difficult to timely and effectively discharge the corrosion debris, and due to the lack of effective pressure and flow adjustment methods, it is easy to cause unstable online chemical instrument measurement, which has a huge impact on the safe operation of the unit.

In order to achieve the above object, the technical scheme adopted in the present invention is:

The present invention provides a centralized water vapor sampling system, which includes several sampling subsystems, control units and sewage expansion vessels; the inlet ports of several sampling subsystems are respectively connected to corresponding sampling ports in the water vapor system, and the outlet ports of several sampling subsystems are respectively connected to corresponding online chemical instruments;

The sampling subsystem includes a sampling pipeline and a shut-off valve, a cooler, an electric pressure regulating valve, a thermostat and an electric flow regulating valve sequentially arranged on the sampling pipeline; wherein, the inlet end of the shut-off valve is connected to the corresponding sampling port in the water vapor system, and the outlet end of the electric flow regulating valve is connected to the inlet end of the online chemical instrument; a sewage outlet is also provided on the sampling pipeline, and the sewage discharge port is arranged between the shut-off valve and the cooler; The inlet end of the blowdown expander is connected;

The control unit is connected to the electric sewage valve, the electric pressure regulating valve and the electric flow regulating valve, and is used to realize the automatic operation control of the electric sewage valve, the electric pressure regulating valve and the electric flow regulating valve.

Further, it also includes a circulating cooling water source; the circulating cooling water source is used to provide circulating cooling water for the cooler and the sewage expansion vessel.

Further, the shut-off valve includes a primary shut-off valve and a secondary shut-off valve connected in sequence.

Further, the cooler is a single-stage cooler or two-stage coolers connected in series.

Further, the control unit includes a first control module, in which automatic blowdown parameters are pre-stored; the first control module is used to generate and send an automatic blowdown instruction to the electric blowdown valve according to the automatic blowdown control parameters; wherein, the automatic blowdown control parameters include the automatic blowdown period and the automatic blowdown duration.

Further, the control unit also includes a second control module, in which automatic pressure adjustment parameters are pre-stored; the sampling subsystem also includes a pressure sensor, the output end of the pressure sensor is connected to the input end of the second control module, and the pressure sensor is used to collect and send the pressure of the water/steam sample before entering the thermostat to the second control module;

The second control module is used to generate and send an automatic pressure regulation command to the electric pressure regulating valve according to the automatic pressure regulation parameter and the pressure of the water/steam sample before entering the thermostat; wherein, the automatic pressure regulation parameter includes the initial opening of the electric pressure regulating valve and the pressure limit of the water/steam sample.

Further, the control unit also includes a third control module, in which automatic flow adjustment parameters are pre-stored; the sampling subsystem also includes a flow sensor; the output end of the flow sensor is connected to the third control module, and the flow sensor is used to collect and send the flow of the water/steam sample before entering the online chemical meter to the third control module;

The third control module is used to generate and send an automatic flow adjustment command to the electric flow adjustment valve according to the automatic flow adjustment parameter and the flow rate of the water/steam sample before entering the online chemical meter; wherein, the automatic flow adjustment parameter includes the initial opening of the electric flow adjustment valve and the flow limit of the water/steam sample.

Further, the sampling subsystem also includes a manual blowdown valve, which is set at the blowdown port and placed at the inlet side of the electric blowdown valve.

The present invention also provides a method for centralized sampling of water vapor, which utilizes the centralized sampling system for water vapor;

Wherein, the concentrated sampling method of water vapor includes:

Turn on the cooler and blowdown expansion container, and ensure that the cooler and blowdown hole container work normally;

Open the shut-off valve, and when the preset sewage discharge limit is reached, the electric sewage valve will automatically open for sewage discharge, and the discharged corrosive debris will enter the sewage expansion container for collection;

When there is no need to discharge sewage, the electric sewage valve is closed; at this time, the water/steam samples flowing out of the sampling port of the water vapor system flow through the stop valve, cooler, electric pressure regulating valve, constant temperature device and electric flow regulating valve in sequence, and then enter the online chemical instrument;

Wherein, the electric pressure regulating valve is used to adjust the pressure of the water/steam sample cooled by the cooler to obtain the water/steam sample after pressure regulation; the constant temperature device is used to adjust the temperature of the water/steam sample after pressure regulation to obtain the water/steam sample after temperature regulation; the electric flow regulating valve is used to regulate the flow rate of the water/steam sample after temperature regulation; the electric sewage valve, the electric pressure regulating valve and the electric flow regulating valve are all automatically controlled by the control unit.

Compared with prior art, the beneficial effect of the present invention is:

The invention provides a water vapor centralized sampling system and method. By setting an electric sewage valve, an electric pressure regulating valve and an electric flow regulating valve on the sampling pipeline of the sampling subsystem, and using a control unit to automatically control the electric sewage valve, electric pressure regulating valve and electric flow regulating valve, the regular automatic sewage discharge, automatic pressure regulation and automatic flow adjustment of the sampling system are realized, and the water/steam samples entering the online chemical instrument are sampled representatively, and the parameters of each water/steam sample meet the measurement requirements of the on-line chemical instrument; The sewage valve realizes automatic sewage discharge control on the side of the high-temperature sampling rack, ensures timely and effective discharge of corrosion debris, effectively maintains the sampling representativeness of the water vapor system, and ensures the accuracy of chemical operation supervision; through the automatic control of the electric pressure regulating valve, the automatic pressure regulation control on the side of the high-temperature sampling rack ensures a stable sampling pressure for water/steam samples and ensures that there are sufficient water/steam samples for online chemical instruments for measurement; through the automatic control operation of the electric flow regulating valve, the flow rate at the low-temperature sampling rack side is automatically adjusted to ensure the stability of water samples measured by online chemical instruments. The accuracy and reliability of the online chemical instrument measurement results are improved, thereby ensuring the safe operation of the unit.

Furthermore, by setting up two-stage coolers in series, the temperature of some water/steam samples with high temperature and high pressure can be completely cooled, ensuring the stability of the online chemical meter measurement results.

Further, by setting the pressure sensor, the automatic pressure adjustment parameters of the second control module, and the pressure of the water/steam sample before entering the online chemical instrument, an automatic pressure regulation command is generated to control and adjust the opening of the electric pressure regulating valve, so as to realize the automatic adjustment of the pressure of the water/steam sample with high adjustment accuracy.

Further, by setting the flow sensor, the automatic pressure adjustment parameters of the third control module and the flow rate of the water/steam sample before entering the online chemical instrument, an automatic flow adjustment instruction is generated to control and adjust the opening of the electric flow adjustment valve, so as to realize the automatic adjustment of the flow rate of the water/steam sample and ensure the timeliness and accuracy of the flow adjustment.

Description of drawings

Fig. 1 is a structural block diagram of the water vapor centralized sampling system described in the embodiment.

Among them, 1 primary shut-off valve, 2 secondary shut-off valve, 3 manual drain valve, 4 electric drain valve, 5 cooler, 6 electric pressure regulating valve, 7 control unit, 8 constant temperature device, 9 flow sensor, 10 electric flow regulating valve, 11 cooler cooling water inlet valve, 12 cooler cooling water outlet valve, 13 blowdown expansion vessel cooling water inlet valve, 14 blowdown expansion vessel cooling water outlet valve, 15 blowdown expansion vessel, 16 pressure sensor.

Detailed ways

In order to make the technical problems, technical solutions and beneficial effects solved by the present invention clearer, the following specific examples will further describe the present invention in detail. It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

The present invention provides a centralized water vapor sampling system, comprising several sampling subsystems, a control unit 7, a sewage expansion vessel 15 and a circulating cooling water source; the inlet ports of several sampling subsystems are respectively connected to corresponding sampling ports in the water vapor system, and the outlet ends of several sampling subsystems are respectively connected to corresponding online chemical instruments; corrosion debris; the blowdown expansion vessel 15 is used to provide circulating cooling water for the cooler 5 and the blowdown expansion vessel 5 in the sampling subsystem.

In the present invention, the sampling subsystem includes a sampling pipeline, a sewage pipeline, a stop valve, a manual sewage valve 3, an electric sewage valve 4, a cooler 5, an electric pressure regulating valve 6, a constant temperature device 8, a flow sensor 9, an electric flow regulating valve 10, a cooler cooling water inlet valve 11, a cooler cooling water outlet valve 12, and a pressure sensor 16.

The inlet end of the sampling pipeline is connected to one of the sampling ports in the water vapor system, and the outlet end of the sampling pipeline is connected to the corresponding online chemical instrument; the stop valve, the cooler 5, the electric pressure regulating valve 6, the pressure sensor 16, the thermostat 8, the flow sensor 9 and the electric flow regulating valve 10 are sequentially arranged on the sampling pipeline; wherein, the stop valve includes a primary stop valve 1 and a secondary stop valve 2 connected in sequence; the cooler 5 is a single-stage cooler or a two-stage cooler connected in series The cooler cooling water inlet valve 11 is installed at the cooling water inlet of the cooler 5, the cooler cooling water outlet valve 12 is installed at the cooling water outlet of the cooler 5, the first outlet of the circulating cooling water source is connected to the cooler cooling water inlet valve 11, and the first return end of the circulating cooling water source is connected to the cooler cooling water outlet valve 12.

The sampling pipeline is also provided with a sewage outlet, and the sewage outlet is arranged between the secondary shut-off valve 2 and the cooler 5; one end of the sewage pipeline is connected to the sewage outlet, and the other end of the sewage pipeline is connected to the inlet of the sewage expansion container 15; The inlet end is provided with a sewage expansion container cooling water inlet valve 13, and the cooling water outlet end of the sewage expansion container 15 is provided with a sewage expansion container cooling water outlet valve 14; the second outlet end of the circulating cooling water source is connected with the sewage expansion container cooling water inlet valve 13, and the second return end of the circulating cooling water source is connected with the sewage expansion container cooling water outlet valve 14.

The control unit 7 is connected to the electric sewage valve 4, the electric pressure regulating valve 6, the pressure sensor 16, the flow sensor 9 and the electric flow regulating valve 10, and is used to realize the automatic operation control of the electric sewage valve 4, the electric pressure regulating valve 6 and the electric flow regulating valve 10.

Specifically, the control unit 7 includes a first control module, a second control module, and a third control module; automatic blowdown parameters are pre-stored in the first control module; the first control module is used to generate and send an automatic blowdown instruction to the electric blowdown valve 4 according to the automatic blowdown control parameters; wherein, the automatic blowdown control parameters include an automatic blowdown period and an automatic blowdown time.

Automatic pressure adjustment parameters are pre-stored in the second control module, and the output end of the pressure sensor 16 is connected to the input end of the second control module. The pressure sensor 16 is used to collect and send the pressure of the water/steam sample before entering the constant temperature device 8 to the second control module; the second control module is used to generate and send an automatic pressure adjustment command to the electric pressure regulating valve 6 according to the automatic pressure adjustment parameters and the pressure of the water/steam sample before entering the constant temperature device 8; Pressure limit for water/steam samples.

Automatic flow adjustment parameters are pre-stored in the third control module, the output end of the flow sensor 9 is connected to the third control module, and the flow sensor 9 is used to collect and send the flow of the water/steam sample before entering the online chemical meter to the third control module; the third control module is used to generate and send an automatic flow adjustment command to the electric flow regulating valve 10 according to the automatic flow regulating parameters and the flow of the water/steam sample before entering the online chemical meter; flow limit.

Working principle and sampling method:

The concentrated water vapor sampling system of the present invention, when the equipment is running, firstly open the cooler cooling water inlet valve 11 and the cooler cooling water outlet valve 12, so that the cooling water of the circulating cooling water source can flow through the cooler 5, to ensure the normal operation of the cooler 5; open the sewage expansion container cooling water inlet valve 13 and the sewage expansion container cooling water outlet valve 14, so that the cooling water of the circulating cooling water source can flow through the sewage expansion container 15, and ensure the normal operation of the sewage expansion container 15.

Open the primary shut-off valve 1 and the secondary shut-off valve 2, and when the water/steam sample in the sampling pipeline reaches the preset blowdown limit value, open the manual blowdown valve 3, and the electric blowdown valve 4 automatically opens for blowdown, and the discharged corrosive debris enters the blowdown expansion container 15 through the blowdown pipe for collection; when there is no need for blowdown, the electric blowdown valve 4 is closed; at this time, the water/steam samples flowing out of the sampling port of the water vapor system flow through the first stop valve 1, the second stop valve 2, the cooler 5, and the electric pressure regulating valve 6 in turn. , a pressure sensor 16, a constant temperature device 8, a flow sensor 9 and an electric flow regulating valve 10, then enter the online chemical instrument for measurement.

In the present invention, the electric pressure regulating valve 6 is used to adjust the pressure of the water/steam sample cooled by the cooler 5 to obtain a water/steam sample after pressure regulation; the constant temperature device 8 is used to adjust the temperature of the water/steam sample after pressure regulation to obtain a temperature-regulated water/steam sample; the electric flow regulating valve 10 is used to regulate the flow of the temperature-regulated water/steam sample;

The centralized water vapor sampling system and method of the present invention, by setting an electric sewage valve, an electric pressure regulating valve and an electric flow regulating valve on the sampling pipeline of the sampling subsystem, and using a control unit to automatically control the electric sewage valve, electric pressure regulating valve and electric flow regulating valve, realizes regular automatic sewage discharge, automatic pressure regulation and automatic flow adjustment of the sampling system, ensuring that the water/steam samples entering the online chemical instrument are representative of sampling, and the parameters of each water/steam sample meet the online chemical instrument measurement requirements.

Example

Take the centralized sampling process of a water vapor system as an example; specifically, take the concentrated water vapor sampling process of 13 sampling ports in the water vapor system as an example.

As shown in accompanying drawing 1, present embodiment provides a kind of water vapor centralized sampling system, comprise ten sampling subsystems, control unit 7, blowdown expander cooling water inlet valve 13, blowdown expander cooling water outlet valve 14, blowdown expander 15 and circulating cooling water source; The 6th and 7th sampling ports of the steam system are connected to the inlet of the 5th sampling subsystem, the 8th and 9th sampling ports of the water vapor system are connected to the inlet of the 6th sampling subsystem, and the 10th to 13th sampling ports of the water vapor system are respectively connected to the inlets of the 7th to 10th sampling subsystems; the outlets of the ten sampling subsystems are respectively connected to an online chemical instrument.

The sampling subsystem includes a sampling pipeline, a sewage pipeline, a primary shut-off valve 1, a secondary shut-off valve 2, a manual sewage valve 3, an electric sewage valve 4, a cooler 5, an electric pressure regulating valve 6, a constant temperature device 8, a flow sensor 9, an electric flow regulating valve 10, a cooler cooling water inlet valve 11, a cooler cooling water outlet valve 12 and a pressure sensor 16.

The inlet end of the sampling pipeline is connected to the corresponding sampling port in the water vapor system, and the outlet end of the sampling pipeline is connected to the corresponding online chemical instrument; the primary shut-off valve 1, the secondary shut-off valve 2, the cooler 5, the electric pressure regulating valve 6, the pressure sensor 16, the thermostat 8, the flow sensor 9 and the electric flow regulating valve 10 are sequentially arranged on the sampling pipeline.

Specifically, the inlet port of the primary stop valve 1 is connected to the corresponding sampling port, the outlet port of the primary stop valve 1 is connected to the inlet port of the secondary stop valve 2, the outlet port of the secondary stop valve 2 is connected to the pipe side inlet of the cooler 5, the pipe side outlet of the cooler 5 is connected to the inlet port of the electric pressure regulating valve 6, the outlet port of the electric pressure regulating valve 6 is connected to one end of the pressure sensor 16, the other end of the pressure sensor 16 is connected to the inlet port of the thermostat 8, and the thermostat 8 The outlet end is connected to one end of the flow sensor 9, the other end of the flow sensor 9 is connected to the inlet end of the electric flow regulating valve 10, and the outlet end of the electric flow regulating valve 10 is connected to an online chemical meter.

The cooler cooling water inlet valve 11 is installed at the shell-side inlet of the cooler 5, and the cooler cooling water outlet valve 12 is installed at the shell-side outlet of the cooler 5; the first outlet end of the circulating cooling water source is connected to the cooler cooling water inlet valve 11, and the first return end of the circulating cooling water source is connected to the cooler cooling water outlet valve 12, so as to provide circulating cooling water to the cooler 5 by using the circulating cooling water source.

It should be noted that the temperature and pressure of the water/steam samples flowing out of the 4th to 10th sampling ports of the water vapor system are relatively high. In this embodiment, the 3rd to 7th sampling systems are used in series.

In this embodiment, the sampling pipeline is also provided with a sewage outlet, and the sewage outlet is arranged between the secondary shut-off valve 2 and the cooler 5; one end of the sewage pipeline is connected to the sewage outlet, and the other end of the sewage pipeline is connected to the inlet port of the sewage expansion container 15, and the manual sewage valve 3 and the electric sewage valve 4 are sequentially arranged on the sewage pipeline.

Specifically, one end of the manual blowdown valve 3 is connected to the blowdown port, the other end of the manual blowdown valve 3 is connected to one end of the electric blowdown valve 4, and the other end of the electric blowdown valve 4 is connected to the pipe side inlet of the blowdown expansion vessel 15; The second outlet port of the sewage expansion vessel is connected to the cooling water inlet valve 13 of the sewage expansion vessel, and the second return water end of the circulating cooling water source is connected to the cooling water outlet valve 14 of the sewage expansion vessel, so as to provide circulating cooling water to the sewage expansion vessel 15 by using the circulating cooling water source.

In this embodiment, the control unit 7 is connected to the electric sewage valve 4, the electric pressure regulating valve 6 and the electric flow regulating valve 10, and is used to realize the automatic operation control of the electric sewage valve 4, the electric pressure regulating valve 6 and the electric flow regulating valve 10; wherein, the control unit 7 includes a first control module, a second control module and a third control module; the first control module is connected to the electric sewage valve 4, the second control module is connected to the electric pressure regulating valve 6 and the pressure sensor 16, and the third control module is connected to the electric flow Both the regulating valve 10 and the flow sensor 9 are connected.

Specifically, automatic blowdown parameters are pre-stored in the first control module; the first control module is used to generate and send an automatic blowdown command to the electric blowdown valve 4 according to the automatic blowdown control parameters; wherein, the automatic blowdown control parameters include the automatic blowdown period and the automatic blowdown duration.

Wherein, the automatic control principle of the electric blowdown valve 4 is as follows:

By presetting the automatic sewage discharge period and the automatic sewage discharge time length in the first control module, after the automatic sewage discharge parameter setting is completed, the first control module can automatically control the switch of the electric sewage discharge valve 4; that is, the first control module generates an automatic sewage discharge instruction to the electric sewage discharge valve 4 at each interval of the automatic sewage discharge cycle, and the electric sewage discharge valve 4 opens after responding to the automatic sewage discharge instruction, and discharges corrosive debris, and automatically closes after the automatic sewage discharge duration of continuous sewage discharge.

Specifically, automatic pressure regulation parameters are pre-stored in the second control module, and the pressure sensor 16 is used to collect and send the pressure of the water/steam sample before entering the constant temperature device 8 to the second control module; the second control module is used to generate and send an automatic pressure regulation command to the electric pressure regulating valve 6 according to the automatic pressure regulation parameter and the pressure of the water/steam sample before entering the constant temperature device 8; wherein, the automatic pressure regulation parameter includes the initial opening of the electric pressure regulating valve 6 and the pressure limit of the water/steam sample.

Wherein, the automatic control principle of the electric pressure regulating valve 6 is specifically as follows:

By presetting the initial opening of the electric pressure regulating valve 6 and the pressure limit of the water/steam sample in the second control module, after the automatic pressure adjustment parameter setting is completed, the pressure sensor 16 collects and sends the pressure of the water/steam sample before entering the thermostat 8 to the second control module; the second control module compares the pressure of the water/steam sample before entering the thermostat 8 with the pressure limit of the water/steam sample, and generates and sends an automatic pressure regulation command to the The electric pressure regulating valve 6, the electric pressure regulating valve 6 will adjust the pressure from the initial opening in response to the automatic pressure regulating command, if the pressure exceeds or falls below the limit value, the electric pressure regulating valve 6 will adjust according to the set opening to ensure that the pressure meets the requirements.

Specifically, automatic flow adjustment parameters are pre-stored in the third control module, and the flow sensor 9 is used to collect and send the flow of the water/steam sample before entering the online chemical meter to the third control module; the third control module is used to generate and send an automatic flow adjustment command to the electric flow regulating valve 10 according to the automatic flow regulating parameters and the flow of the water/steam sample before entering the online chemical meter; wherein, the automatic flow regulating parameters include the initial opening of the electric flow regulating valve 10 and the flow limit of the water/steam sample.

Wherein, the automatic control principle of the electric flow regulating valve 10 is specifically as follows:

By presetting the initial opening of the electric flow regulating valve 10 and the flow limit of the water/steam sample in the third control module, after the flow automatic adjustment parameter setting is completed, the flow sensor 9 collects and sends the flow of the water/steam sample before entering the online chemical meter to the third control module; the third control module compares the flow of the water/steam sample before entering the online chemical meter with the flow limit of the water/steam sample, and generates and sends an automatic flow adjustment command to the electric flow according to the comparison result and in combination with the initial opening of the electric flow regulating valve 10 Regulating valve 10: The electric flow regulating valve 10 will adjust the flow from the initial opening in response to the automatic flow regulating command. If the flow exceeds or falls below the limit value, the electric flow regulating valve 10 will adjust according to the set opening to ensure that the flow meets the requirements.

The present embodiment also provides a method for concentrated sampling of water vapor, comprising the following steps:

When the unit is turned on, the water vapor centralized sampling system needs to be put into operation; firstly, circulating cooling water needs to be put in, that is, the cooler cooling water inlet valve 11 and the cooler cooling water outlet valve 12 are opened, so that the cooling 5 is in working condition;

When sampling starts, open the primary shut-off valve 1 and the secondary shut-off valve 2. When the water/steam sample in the sampling pipeline reaches the preset blowdown limit value, open the manual blowdown valve 3, and the electric blowdown valve 4 automatically opens for blowdown, and the discharged corrosive debris enters the blowdown expander 15 through the blowdown pipe for collection; when blowdown is not required, the electric blowdown valve 4 is closed; , electric pressure regulating valve 6, pressure sensor 16, constant temperature device 8, flow sensor 9 and electric flow regulating valve 10, then enter the online chemical instrument for measurement.

Specifically, after the primary stop valve 1 and the secondary stop valve 2 are opened, the water sample flows through the cooler 5 and then reaches the electric pressure regulating valve 6, and enters the constant temperature device 8 after the pressure adjustment is completed; the water sample enters the flow sensor 9 and the electric flow regulating valve 10 after the temperature is adjusted by the constant temperature device 8, and enters the online chemical instrument after adjusting the flow rate to measure the water vapor quality.

The automatic blowdown parameter for automatically controlling the electric blowdown valve 4 is set in the control unit 7; when the automatic blowdown parameter setting is completed, the electric blowdown valve 4 is opened at every interval of the automatic blowdown cycle to discharge corrosive debris and automatically close after a long time for the automatic blowdown of the blowdown; the automatic pressure regulation parameter for automatically controlling the electric pressure regulating valve 6 is set in the control unit 7; , the electric pressure regulating valve 6 will adjust the pressure from the initial opening to ensure that the pressure meets the requirements; the automatic flow adjustment parameters for automatically controlling the electric flow regulating valve 10 are set in the control unit 7; after the automatic flow regulating parameters are set, according to the comparison result between the flow of the water/steam sample before entering the online chemical instrument and the flow limit of the water/steam sample, the electric flow regulating valve 10 will start to adjust the flow from the initial opening to ensure that the flow meets the requirements.

In this embodiment, the control unit 7 controls the electric blowdown valve 4, the electric pressure regulating valve 6 and the electric flow regulating valve 10 to automatically adjust to ensure that the parameters of the water samples of the online chemical instrument meet the measurement requirements; wherein, the electric blowdown valve on the side of the high-temperature sampling rack adopts an automatic blowdown method, and the electric blowdown valve 4 automatically executes the blowdown procedure after setting the relevant parameters of blowdown; the electric pressure regulating valve on the side of the high-temperature sampling stand adopts an automatic adjustment method. An electric flow regulating valve 10 is used on the side of the sampling rack to regulate the flow of water samples entering the online chemical meter to ensure that the flow of water samples entering the online chemical meter meets the requirements; the control unit 7 can adjust the opening of the electric pressure regulating valve 6 and the opening of the electric flow regulating valve 10 according to the flow situation in time to ensure that the pressure and flow of the water/steam sample are stable and meet the measurement requirements; preferably, for some water/steam samples with high temperature and pressure, they can be cooled in two stages, that is, two coolers 5 are connected in series to achieve the purpose of complete cooling.

In the water vapor centralized sampling system and method described in the present invention, the sewage valve on the side of the high-temperature sampling rack is automatically discharged to prevent the operator from manually opening and closing the valve, thereby avoiding the occurrence of safety problems; secondly, regular sewage discharge helps to maintain the representativeness of water vapor system sampling, thereby ensuring the accuracy of chemical operation supervision; the invention realizes automatic pressure regulation of the pressure regulating valve on the side of the high-temperature sampling rack, thereby ensuring the stability of the sampling pressure and ensuring that there are sufficient water samples for online chemical instrument measurement; The measured water sample is stable, making the measurement accurate and reliable.

In the present invention, by adding an electric sewage valve, an electric pressure regulating valve and an electric flow regulating valve, and using the control unit for automatic control, the centralized water vapor sampling system can realize the functions of automatic sewage discharge, automatic pressure regulation and automatic flow adjustment, and ensure that the water/steam samples entering the online chemical meter are representative of sampling and that the parameters of each water/steam sample meet the measurement requirements of the online chemical meter; .

The above-described embodiment is only one of the implementations that can realize the technical solution of the present invention. The scope of protection claimed by the present invention is not only limited by this embodiment, but also includes any changes, replacements and other implementations that are easily conceivable by those skilled in the art within the technical scope disclosed in the present invention.

Claims (9)

1. a kind of water vapor centralized sampling system, it is characterized in that, comprises some sampling subsystems, control unit (7) and blowdown expander (15); The inlet end of some described sampling subsystems is connected with corresponding sampling port in the water vapor system respectively, and the outlet end of some described sampling subsystems is connected with corresponding on-line chemical instrument respectively; The sampling subsystem includes a sampling pipeline and a cut-off valve, a cooler (5), an electric pressure regulating valve (6), a thermostat (8) and an electric flow regulating valve (10) arranged sequentially on the sampling pipeline; wherein, the inlet end of the shut-off valve is connected to the corresponding sampling port in the water vapor system, and the outlet end of the electric flow regulating valve (10) is connected to the inlet end of an online chemical instrument; a sewage outlet is also provided on the sampling pipeline, and the sewage discharge outlet is arranged between the shut-off valve and the cooler (5); An electric blowdown valve (4) is installed at the blowdown outlet, and the outlet end of the electric blowdown valve (4) is connected to the inlet end of the blowdown expander (15); The control unit (7) is connected to the electric sewage valve (4), the electric pressure regulating valve (6) and the electric flow regulating valve (10), and is used to realize the automatic operation control of the electric sewage valve (4), the electric pressure regulating valve (6) and the electric flow regulating valve (10). 2. A centralized water vapor sampling system according to claim 1, further comprising a circulating cooling water source; the circulating cooling water source is used to provide circulating cooling water for the cooler (5) and the blowdown expansion vessel (15). 3. A centralized water vapor sampling system according to claim 1, characterized in that the cut-off valve comprises a primary cut-off valve (1) and a secondary cut-off valve (2) connected in sequence. 4. A centralized water vapor sampling system according to claim 1, characterized in that the cooler (5) is a single-stage cooler or a two-stage cooler connected in series. 5. A centralized water vapor sampling system according to claim 1, wherein the control unit (7) comprises a first control module, and automatic blowdown parameters are pre-stored in the first control module; the first control module is used to generate and send an automatic blowdown instruction to the electric blowdown valve (4) according to the automatic blowdown control parameters; wherein, the automatic blowdown control parameters include an automatic blowdown period and an automatic blowdown duration. 6. a kind of water vapor concentrated sampling system according to claim 1, it is characterized in that, described control unit (7) also comprises the second control module, and automatic pressure adjustment parameter is prestored in the described second control module; Described sampling subsystem also comprises pressure sensor (16), and the output end of described pressure sensor (16) is connected with the input end of described second control module, and described pressure sensor (16) is used for collecting and sending the pressure of the water/steam sample before entering described thermostat (8) to described second control module; The second control module is used to generate and send an automatic pressure regulation command to the electric pressure regulating valve (6) according to the automatic pressure regulation parameter and the pressure of the water/steam sample before entering the thermostat (8); wherein, the automatic pressure regulation parameter includes the initial opening of the electric pressure regulating valve (6) and the pressure limit of the water/steam sample. 7. a kind of water vapor concentrated sampling system according to claim 1, it is characterized in that, described control unit (7) also comprises the 3rd control module, in the described 3rd control module, automatic flow adjustment parameter is pre-stored; Described sampling sub-system also comprises flow sensor (9); The output end of described flow sensor (9) is connected with the described 3rd control module, and described flow sensor (9) is used for collecting and sending the flow of the water/steam sample before entering described on-line chemical instrument to described 3rd control module; The third control module is used to generate and send an automatic flow adjustment command to the electric flow adjustment valve (10) according to the automatic flow adjustment parameter and the flow rate of the water/steam sample before entering the online chemical meter; wherein, the automatic flow adjustment parameter includes the initial opening of the electric flow adjustment valve (10) and the flow limit of the water/steam sample. 8. A centralized water vapor sampling system according to claim 1, wherein the sampling subsystem further comprises a manual drain valve (3), and the manual drain valve (3) is arranged at the drain outlet and placed on the inlet side of the electric drain valve (4). 9. A kind of water vapor concentrated sampling method, is characterized in that, utilizes a kind of water vapor concentrated sampling system as described in any one of claim 1-8; Wherein, the concentrated sampling method of water vapor includes: Open the cooler (5) and the sewage expansion container (15), and ensure that the cooler (5) and the sewage hole container (15) work normally; Open the shut-off valve, and when the preset sewage discharge limit value is reached, the electric sewage discharge valve (4) is automatically opened for sewage discharge, and the discharged corrosive debris enters the sewage discharge expander (15) for collection; When there is no need for blowdown, the electric blowdown valve (4) is in the closed state; at this time, the water/steam samples flowing out of the sampling port of the water vapor system flow through the shut-off valve, cooler (5), electric pressure regulating valve (6), thermostat (8) and electric flow regulating valve (10) in sequence, and then enter the online chemical instrument; Wherein, the electric pressure regulating valve (6) is used to adjust the pressure of the water/steam sample cooled by the cooler (5) to obtain the water/steam sample after pressure regulation; the constant temperature device (8) is used to regulate the temperature of the water/steam sample after pressure regulation to obtain the water/steam sample after temperature regulation; the electric flow regulating valve (10) is used to regulate the flow rate of the water/steam sample after temperature regulation; ) are automatically controlled by the control unit (7).