1. The multichannel high-precision static dilution system is characterized by comprising a fixed dilution ratio module, an arbitrary dilution ratio module, a static dilution gas parallel storage module, a static dilution gas series storage module and a six-channel parallel gas storage module, basically covering the gas configuration requirements required by all gas analysis systems, and combining the two dilution modules and the three storage devices to realize different dilution and storage requirements.

2. The system of claim 1, wherein the fixed dilution ratio module is characterized in that a high-precision volume calibration method and a path of large-flow diluent gas are used for carrying out high-precision dilution on the diluted gas, single-point position diluent gas calibration and compensation are adopted, the highest-precision multi-concentration dilution process is realized by changing different gas tank volumes and quantitative ring volumes, the process has no theoretical dead volume, and dilution errors are derived from gas flow disturbance and diluent gas input precision caused by control valve switching in the system operation process.

3. The system of claim 1, wherein the arbitrary dilution ratio module is characterized in that a path of high-flow diluent gas and a path of low-flow sample gas are used for time-sharing gas intake, single-point calibration and compensation of the diluent gas are adopted, multi-point calibration and compensation of the sample gas are used for realizing the arbitrary dilution ratio, and the minimum disturbance of the sample system is ensured through a buffer cavity, flow splitting and flow limiting.

4. A module as claimed in claim 2 or claim 3, having the specific structure comprising: a fixed dilution ratio control module (A), an arbitrary dilution ratio control module (B), a dilution gas input (1), a sample gas input (2), a fixed dilution ratio module output (3), an evacuation port (4), a six-way valve (5), a dilution gas quality control module (6), a sample gas quality control module (7), a quantification module (8), a six-way valve drive module (9), a dilution gas input control module (10), a sample gas input control module (11), a dry gas input control valve (12), a wet gas input control valve (13), a humidifier (14), a dry gas input one-way valve (15), a wet gas input one-way valve (16), a dilution gas input (17), a sample gas shunt output (18), a sample gas input (19), an arbitrary dilution ratio output (20), an evacuation port (21), a dilution gas input control module (22), a sample gas shunt control module (23), The device comprises a sample gas input control module (24), a dilution gas quality control module (25), a sample gas quality control module (26), a buffer cavity (27), a dry gas input control valve (28), a wet gas input control valve (29), a humidifier (30), a flow limiting control valve (31), a wet gas input one-way valve (32), a dry gas input one-way valve (33), a dilution gas input switching valve (34) and a sample gas input switching valve (35).

5. The system of claim 1, wherein the static parallel dilution gas storage module is characterized in that two parallel gas tanks are used for gas storage, the system is cleaned by dilution gas, humidified gas and a vacuum pump, the gas flow is changed by means of a switching valve, and the gas output is controlled by a pressure control flow module or directly.

6. The system of claim 1, wherein the static dilution gas serial storage module is characterized in that the module uses two serially connected gas tanks for gas storage, performs system cleaning by means of dilution gas, humidified gas and a vacuum pump, performs gas flow transformation by means of a switching valve, performs gas output directly or by means of a pressure control flow module.

7. The system of claim 1, wherein the six-channel parallel gas storage module is characterized in that six parallel gas tanks are used for gas storage, the system is cleaned by dilution gas, humidified gas and a vacuum pump, the gas flow is changed by means of a switching valve, and the gas output is directly carried out by a pressure control flow module.

8. A module according to claim 5 or 6 or 7, the specific structure of which comprises the following components: static dilution gas parallel storage (C), static dilution gas series storage (D), six-channel parallel gas storage (E), static dilution gas parallel gas input (36), tank cleaning vacuum pump (37), static dilution gas constant current output (38), static dilution gas through output (39), evacuation port (40), switch two-way valve (41), three-way valve (42), three-way valve (43), three-way valve (44), three-way valve (45), three-way valve (46), switch two-way valve (47), three-way valve (48), switch two-way valve (49), gas tank (50), gas tank (51), pressure sensor (52), pressure sensor (53), static dilution gas constant current output control module (54), static dilution gas series gas input (55), tank cleaning vacuum pump (56), static dilution gas constant current output (57), static dilution gas through output (58), An evacuation port (59), a switch two-way valve (60), a three-way valve (61), a three-way valve (62), a pressure sensor (63), a three-way valve (64), a switch two-way valve (65), a static dilution gas constant-current output control module (66), a gas tank (67), a gas tank (68), a six-channel parallel gas input (69), a tank cleaning vacuum pump (70), a static dilution gas constant-current output (71), a static dilution gas direct-connection output (72), an evacuation port (73), a switch two-way valve (74), a three-way valve (75), a three-way valve (76), a three-way valve (77), a switch two-way valve (78), a pressure sensor (79), a single-input multi-output valve control (80), a single-input multi-output valve inlet (81), a multi-input single-output valve output (82), a gas tank (83), a gas tank (84), a gas tank (85), a gas tank (86), a gas tank (87), a gas tank (88), And a static diluent gas constant current output control module (89).

Background art:

1. the gas static dilution method is mainly used for calibrating and controlling a target gas quantitative analysis system, most of the current high-precision products are imported products, the imported products are limited by the products, different devices are adopted for gas dilution and cleaning, the dilution ratio range is narrow, a plurality of devices are required to be connected in series for achieving the target effect in many cases, and meanwhile, the series connection brings larger errors;

2. most domestic equipment is a dynamic dilution method which is limited by principles, the dynamic dilution method cannot perform high-precision control on high dilution ratio accuracy, and meanwhile, the dynamic method consumes more standard gases, and the price of a plurality of standard gases is very high, so that high operation cost is generated;

3. many manufacturers use commercially available flow controllers for control purposes, and when calibrating and quality controlling high sensitivity and high accuracy devices, the accuracy and reproducibility are not satisfactory.

The invention content is as follows:

the purpose of the invention is as follows:

1. modular design is used to achieve multiple different dilution ratios and different precision gas auto-dilution, automated system cleaning, quality control and auto-export processes.

2. The influence of dead volume on the result can be effectively controlled by using the processing pipeline and the interface, and the system error can be clearly evaluated.

The implementation process comprises the following steps:

1. fixed dilution ratio module: the module utilizes a high-precision volume calibration method and a path of large-flow diluent gas to carry out high-precision dilution on the diluted gas, adopts single-point position diluent gas calibration and compensation, and realizes the dilution process with highest precision and multiple concentrations by changing different gas tank volumes and quantitative ring volumes.

2. Module of arbitrary dilution ratio: the module utilizes one path of high-flow diluent gas and one path of low-flow sample gas to carry out a time-sharing gas inlet mode, adopts single-point calibration and compensation of the diluent gas, realizes any dilution ratio of the multi-point calibration and compensation of the sample gas, and ensures the minimum disturbance of a sample system through a buffer cavity, a flow dividing mode and a flow limiting mode.

3. The static diluent gas parallel storage module: the module utilizes two parallel gas tanks to store gas, carries out system cleaning through diluent gas, humidifying gas and a vacuum pump, and carries out gas flow transformation in a switching valve mode. The gas output is carried out through a pressure control flow module or directly.

4. The static dilution gas series storage module: the module utilizes two gas tanks connected in series to store gas, carries out system cleaning through diluent gas, humidifying gas and a vacuum pump, and carries out gas flow transformation in a switching valve mode. The gas output is carried out through a pressure control flow module or directly.

5. Six-channel parallel gas storage module: the module utilizes six parallel gas tanks to store gas, carries out system cleaning through diluent gas, humidifying gas and a vacuum pump, and carries out gas flow conversion in a switching valve mode. The gas output is carried out through a pressure control flow module or directly.

The implementation process embodies the technical characteristics:

1. high precision dilution module (fixed dilution ratio module): the process has no theoretical dead volume, and the dilution error comes from airflow disturbance and dilution gas input precision caused by control valve switching in the system operation process.

2. Common precision dilution module (arbitrary dilution ratio module): the dilution error is derived from air flow disturbance, dilution gas and sample gas input precision brought by control switching in the system operation process, and the system is slightly larger than the fixed dilution ratio module error.

3. A parallel storage mode: the method is characterized in that under the condition of low use frequency, a tank of gas is always available, and the cleaning process, the gas distribution and the use cannot interfere with each other.

4. A serial storage mode: the mode is characterized in that higher gas consumption can be realized, and when the gas consumption of single use is large, the mode can be used for gas distribution and storage.

5. Six-channel parallel storage mode: this approach can be used when calibration of the gas analysis apparatus is required using multiple different concentrations of gas.

The invention has the following effects:

the dilution system basically covers the gas configuration requirements required by all gas analysis systems, and two dilution modules and three storage devices are combined to realize application conditions required by different requirements. When the internal standard or the quality control is used, high-precision connection with any storage device is used; when the outer standard is used, the connection can be carried out by using a high-precision and six-channel parallel storage mode; any combination of three storage devices may be used if any dilution ratio is desired for the gas configuration.

Description of the drawings:

FIG. 1 Multi-channel static dilution System input

FIG. 2 Multi-channel static dilution System storage

In fig. 1: a fixed dilution ratio control module (A); an arbitrary dilution ratio control module (B); a dilution gas input (1); a sample gas input (2); a fixed dilution ratio module output (3); an evacuation port (4); a six-way valve (5); a dilution gas quality control module (6); a sample gas quality control module (7); a dosing module (8); a six-way valve drive module (9); a diluent gas input control module (10); a sample gas input control module (11); a dry gas input control valve (12); a moisture input control valve (13); a humidifier (14); the dry gas is input into a one-way valve (15); a moisture input check valve (16); a dilution gas input (17); a sample gas split output (18); a sample gas input (19); an arbitrary dilution ratio output (20); a drain (21); a diluent gas input control module (22); a sample gas flow dividing control module (23); a sample gas input control module (24); a dilution gas quality control module (25); a sample gas quality control module (26); a buffer chamber (27); a dry gas input control valve (28); a moisture input control valve (29); a humidifier (30); a current limit control (31); a moisture input check valve (32); a drying gas input check valve (33); a diluent gas input switching valve (34); a sample gas input switching valve (35);

in fig. 2: storing the static dilution gas in parallel (C); storing the static dilution gas in series (D); six-channel parallel gas storage (E); the static dilution gas is connected with a gas input (36) in parallel; a canister cleaning vacuum pump (37); a static dilution gas constant current output (38); a static dilution gas feed-through output (39); a drain (40); switching a two-way valve (41); a three-way valve (42); a three-way valve (43); a three-way valve (44); a three-way valve (45); a three-way valve (46); switching a two-way valve (47); a three-way valve (48); switching a two-way valve (49); a gas tank (50); a gas tank (51); a pressure sensor (52); a pressure sensor (53); a static diluent gas constant-current output control module (54); a static dilution gas series gas input (55); a canister cleaning vacuum pump (56); a static dilution gas constant current output (57); a static dilution gas pass-through output (58); a drain (59); switching a two-way valve (60); a three-way valve (61); a three-way valve (62); a pressure sensor (63); a three-way valve (64); switching a two-way valve (65); a static diluent gas constant-current output control module (66); a gas tank (67); a gas tank (68); a six-channel parallel gas input (69); a canister cleaning vacuum pump (70); a static dilution gas constant current output (71); a static dilution gas straight-through output (72); an evacuation port (73); switching a two-way valve (74); a three-way valve (75); a three-way valve (76); a three-way valve (77); switching a two-way valve (78); a pressure sensor (79); a single-in multiple-out valve control (80); a single-inlet multiple-outlet valve inlet (81); a multiple-in single-out valve output (82); a gas tank (83); a gas tank (84); a gas tank (85); a gas tank (86); a gas tank (87); a gas tank (88); a static diluent gas constant-current output control module (89);

the specific implementation mode is as follows:

1. cleaning mode:

1.1 dry/wet gas cleaning mode switching: the switches (13) and (29) of the switches (12) and (28) are in a dry gas cleaning mode, and the switches (12) and (28) of the switches (13) and (29) are in a wet gas cleaning mode;

1.2 tank cleaning:

connecting (3) in a fixed dilution ratio control module (A) with a static diluent gas parallel storage (C) (36), connecting in a static diluent gas series storage (D) (55), connecting in a static diluent gas six-channel storage (E) (69), or connecting (20) in any dilution ratio control module (B) with a static diluent gas parallel storage (C) (36), a static diluent gas series storage (D) (55), and a static diluent gas six-channel storage (E) (69), closing gas tank inlet valves (42), (46), (61), (75), opening vacuum pumps (37), (56), (70), opening pre-cleaned gas tank valves (43), (45), or (62), or (75), monitoring pressure gauges (52), (53), (63), (79), keeping the pressure gauges below 0.5psi (gauge pressure) for more than 10 minutes, and simultaneously opening dilution flow control (10), (22), 100-1000 ml/min, selecting (C) three-way valve (41) (47) direction (40), (D) three-way valve (60) direction (59), (E) three-way valve (74) direction (73) as evacuation mode, when vacuum maintenance is completed, closing pump (37) (56) (70) and pre-cleaning gas tank valve (43) or (45) or (62) or (75), charging air for cleaning, switching evacuation three-way valve (41) (47) (60) (74) to gas tank, opening tank air inlet valve (42) (46) (61) (75), monitoring pressure gauge (52) (53) (63) (79), making pressure gauge lower than 30psi, when six-channel storage cleaning, controlling (80) single-in and multiple-out valve (81) and multiple-in and single-out valve (82) to align with corresponding gas tank (83) (84) (85) (86) (87) (88), according to adsorption performance of diluted gas to silanized surface, dry/wet gas cleaning can be selected, the gas tank can be heated to the maximum 150 ℃ to ensure higher cleaning efficiency, 3-5 cycles can be performed, if the gas is strongly adsorbed gas (such as sulfide), the wet gas is required to be used for cleaning, the cycle number can be increased according to the measured residual situation, after the tank cleaning is finished, the state in the tank is about 30psi, the input and output valves of the tank are all in a closed state (42), (43), (44), (45), (46), (48), (61), (62), (64), (75), (77), the three-way valve (41), (47) direction (40), (D) three-way valve (60) direction (59), and (E) three-way valve (74) direction (73) are selected as an emptying mode.

2. And (3) leak detection mode:

and after the operation tank is cleaned, operating the leak detection mode method and continuously inflating. Switching evacuation three-way valves (41) (47) (60) (74) to point to the gas tank, opening tank inlet valves (42) (46) (61) (75), monitoring pressure gauges (52) (53) (63) (79), keeping the pressure gauges to 45psi, closing the input gas and the gas tank inlet valves (42) (46) (61) (75), standing for 8 hours, and obtaining the gas-tight state when the pressure drop is less than 0.5psi (differential pressure).

3. And (3) gas distribution mode:

3.1 constant-current precision control of sample gas input in a high-precision mode: the volume precision of the quantitative module (8) determines the gas distribution precision.

3.2 constant-current precision control of sample gas input in a common mode: through flow control module (24) sample gas flow volume input, reposition of redundant personnel module (23) control current-limiting control input end (31) pressure stability, offset valve rotation through cushion chamber (27) and to the input gas disturbance influence.

3.3 connecting (3) in the fixed dilution ratio control module (A) with the static dilution gas parallel storage (C) (36), connecting in the static dilution gas series storage (D) (55), connecting in the static dilution gas six-channel storage (E) (69), or connecting (20) in the arbitrary dilution ratio control module (B) with the static dilution gas parallel storage (C) (36), in the static dilution gas series storage (D) (55), and in the static dilution gas six-channel storage (E) (69), closing the gas tank inlet valves (42) (46) (61) (75), opening the vacuum pumps (37) (56) (70), opening the pre-cleaned gas tank valve (43) or (45) or (62) or (75 psi), monitoring the pressure gauges (52) (53) (63) (79), keeping below 0.5 (absolute) for more than 5 minutes, and simultaneously opening the dilution flow control (10) (22) and the sample gas control (11) (23) (24), the dilution flow control selects a fixed value in 100-1000 ml/min according to the dilution ratio, the (C) three-way valve (41) (47) pointing to (40), (D) three-way valve (60) pointing to (59), and (E) three-way valve (74) pointing to (73) are selected as an emptying mode, the (11), (23) (24) sample gas control flow is 0.5-30 ml/min, the high-precision mode six-way valve (9) is closed and is in an emptying state, and the normal-precision mode three-way valve (35) pointing to (21) is in an emptying state. When the vacuum maintenance is finished, the pump (37) (56) (70) and the pre-cleaning gas tank valve (43) or (45) or (62) or (75) are closed, the emptying three-way valves (41) (47) (60) (74) are switched to point to the gas tank, the tank air inlet valves (42) (46) (61) (75) are opened, metering according to the expected required concentration is started, when the pressure reaches 15psi (absolute pressure), the high-precision mode opens the six-way valve, and the dilution gas enters the gas tank together with the sample gas until the gas tank reaches the expected dilution ratio pressure; and switching the dilution gas three-way valve to empty in a common precision mode, switching the sample gas three-way valve to a gas tank, calculating the entering volume according to time and flow until the sample gas required by the expected dilution ratio is reached, and switching the dilution gas three-way valve to enable the gas to point to the gas tank to reach the final dilution ratio pressure.

4. And (3) output mode:

4.1 output mode off: gas output valves (49) (66) (78) direct the constant flow outputs (38) (57) (71) closing the constant pressure flow control outputs (54) (66) (89).

4.2 constant current output mode: the gas output valves (49) (66) (78) direct the constant flow outputs (38) (57) (71), control the constant pressure flow control outputs (54) (66) (89), and calibrate and correct the constant pressure flow control outputs as needed.

4.3 direct output mode: gas output valves (49) (66) (78) are directed to direct outputs (38) (57) (71).

5. Data collection, analysis and quality control

5.1 data acquisition: and (3) ensuring the integrity of data, wherein 1/10-second-level time calibration is carried out on flow control systems (10) (11) (22) (23) (24), and the concentration precision can be ensured by matching the data acquisition frequency of the quality control flowmeter, usually 1-10 Hz.

5.2 data analysis: the starting time of the method and the switching time of different valves are recorded, and correction, integral calculation and error analysis are carried out according to the data of mass flow, temperature and the like entering the gas tank. The high-precision mode carries out concentration calculation according to the volume of the quantitative module and the volume of the integral of the dilution gas, and the common precision mode carries out concentration calculation according to the volume of the integral of the dilution gas and the volume of the sample gas.

5.3 gas concentration quality control: and simultaneously, collecting the data of the flow control system and the volume of the quality control flow flowmeter, and meanwhile, integrating the flow of the control system and the quality control flow and calculating errors.

The implementation effect is as follows:

a) internal standard evaluation: the method is used in gas analysis internal standard evaluation, and internal standard gas is added into a gas sampling end so as to evaluate a relative response factor.

b) External standard evaluation: the method is used in the evaluation of the external standard of gas analysis, single-point concentration sampling different time control or multi-point concentration same time sampling control is configured, and the correlation coefficient of a curve is larger than 0.999 under the same concentration gradient.

c) And (3) repeatability evaluation: in the gas analysis repeatability evaluation, the relative standard deviation of the measurement results of repeated gas distribution is less than 3% at different time periods and under different environmental temperatures (temperature difference +/-10 ℃).