Automated online preparation and degassing of volatile samples for on-line analysis

Abstract

An analytical system includes a degassing unit, at least one first valve, and at least one second valve. The at least one first valve is fluidically coupled to the top of the degassing unit and is configured to selectively connect the degassing unit to a replacement gas flow and to a vacuum source. The at least one second valve is fluidically connected to a lateral side of the degassing unit and separately to the bottom of the degassing unit. The at least one second valve is selectively connected to a sample-carrying fluid source, a transfer line configured to deliver a sample to an analytical device, or a waste output.

Description

Background Art

[0001] In many laboratory settings, it's common to analyze a large number of chemical or biological samples at once. To streamline this process, sample manipulation has become mechanized. This mechanized sampling is known as automated sampling and can be performed using an automated sampling device or autosampler.

[0002] Inductively coupled plasma (ICP) spectrometry is an analytical technique commonly used to determine the concentration and isotope ratios of trace elements in liquid samples. ICP spectrometry employs electromagnetically generated, partially ionized argon plasma, which reaches temperatures of approximately 7,000 K. When a sample is introduced into the plasma, the high temperature causes the sample atoms to become ionized or emit light. Because each chemical element produces a characteristic mass or emission spectrum, measuring the spectrum of the emitted matter or light allows the elemental composition of the original sample to be determined.

[0003] A sample introduction system can be used to introduce a liquid sample into an ICP spectrometer (e.g., an inductively coupled plasma mass spectrometer (ICP / ICP-MS), an inductively coupled plasma atomic emission spectrometer (ICP-AES), or a similar instrument), or other sample detector or analytical instrument for analysis. For example, the sample introduction system can extract an aliquot of a liquid sample from a container and then deliver the aliquot to a nebulizer, which converts the aliquot into a polydisperse aerosol suitable for ionization in a plasma by an ICP spectrometer. The aerosol is then classified in a spray chamber to remove larger aerosol particles. After leaving the spray chamber, the aerosol is introduced into the plasma by the plasma torch assembly of the ICP-MS or ICP-AES instrument for analysis. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] The detailed description will be described with reference to the accompanying drawings.

[0005] Figures 1 to 6 is a series of environmental views illustrating how a sample-carrying fluid first forms bubbles, which can collect and potentially form voids within tubing associated with an analytical system.

[0006] Figure 7 is an environmental view of an analytical system designed to minimize bubble formation within a sample-carrying fluid, according to an exemplary embodiment of the present disclosure.

[0007] Figures 8 to 12 yes Figure 7 A series of environmental views of an analysis system illustrating a process by which the analysis system may be used to minimize bubble formation within tubing associated therewith. DETAILED DESCRIPTION

[0008] Overview

[0009] In various analytical systems, a transport fluid, such as ammonium hydroxide (NH4OH), can be used as a transport solution to transport the sample from the circuit inlet to the waste circuit or nebulizer. In one embodiment, the transport fluid can be 29% NH4OH. This solution can remain under pressure, and if analysis is started immediately without waiting for the sample to depressurize, the plasma will extinguish. Depending on the position of the valve, depressurization can cause the NH4OH to flow to waste or the nebulizer.

[0010] Figures 1 to 6 The example analysis system 1000 shown in FIGURE 1 can help illustrate the development of bubbles and / or voids that may occur. The analysis system 1000 can include a circuit inlet 1010, tubing 1020 (shown as a straight tube for ease of illustration, but which can be in the form of a circuit of tubing, for example), and a circuit outlet 1030, which can be in the form of, for example, a nebulizer and / or a waste circuit. The tubing 1020 can be configured to receive and facilitate the transport of a carrier fluid S2 (e.g., a sample material such as NH4OH carried in a carrier fluid) therethrough. While awaiting decompression, a plurality of tiny bubbles 1040 (e.g., having a diameter less than half the diameter of the tubing 1020) can form on the side of the tubing 1020 extending between the circuit inlet 1010 and the circuit outlet 1030 (e.g., in the form of a waste circuit and / or a nebulizer).

[0011] from Figure 1 As can be seen from FIG, when the pressure is initially reduced, no bubbles 1040 are present in the tube 1020. Figure 2 At the beginning of the analysis, the sample S2 may be stable, with some bubbles 1040 forming, but no or substantially no bubbles 1040 are able to enter the nebulizer and / or ICPMS. Figure 3 As shown, decompression can be expected to be complete after about two minutes, and then sample flow (e.g., 100 μL / min) will begin in tubing 1020. Figure 4 It can be seen that some of the small bubbles 1040 can be pushed together by the flow in the small diameter tubing 1020 and begin to form larger bubbles 1050 (e.g., larger than the small bubbles 1040 and having a diameter that may be greater than half the diameter of the tubing 1020). Figure 5 and Figure 6 Eventually, enough bubbles 1040 and / or 1050 can be pushed together to form voids 1060 in the liquid sample S2.

[0012] A void 1060 can be defined as a lack of sample fluid within the tubing 1020 that extends the full diameter of the tubing 1020. In an embodiment, the void 1060 can be in the form of a gas pocket within the tubing 1020. As this void 1060 is pushed down the tubing, it can grow because it draws more gas bubbles 1040, 1050 (e.g., Figure 6 1060) and / or other voids 1060 are added to the sample. In some embodiments, there may be approximately 5-6 such large voids 1060 in a loop or flow path segment at a given time. Given this problem, a method is needed to degas the sample at a remote location to prevent bubbles from accumulating in the transport tubing and forming voids.

[0013] Exemplary embodiments

[0014] Overall reference Figures 7 to 12 , shows and describes an example analytical system 100 configured to degas a sample at a remote location to prevent bubbles from accumulating and forming voids. Figure 7As shown, the analysis system 100 can generally include at least one first valve 102 (e.g., a first multi-port valve, which can be a V5-P3 valve according to the illustrated embodiment), at least one second valve 104 (e.g., a second multi-port valve, which can be a V4-P6 valve according to the illustrated embodiment), at least one third valve 106 (e.g., a third multi-port valve, which can be a V3-P3 valve according to the illustrated embodiment), a vacuum pump 108, a manifold 110, a degassing unit 112 (e.g., a pillar tee connector, according to the illustrated embodiment, with two longitudinally spaced fluid connection ports and one lateral fluid connection port), a sample inlet 114, at least one waste outlet 116 (e.g., 116A, 116B), a plurality of fluid lines 118 (e.g., pipes, tubing, etc.) to fluidically connect the various components together, and a central analysis device (not shown) for testing the prepared sample fluid. In an embodiment, the vacuum pump 108 and the first waste outlet 116A are coupled to the manifold 110. The vacuum pump 108 can be fluidically coupled to the at least one first valve 102 via a first fluid line 118A. The system 100 can further include a degassing unit 112 (e.g., a ¾-inch column tee) oriented to define a top unit extension 112A, a bottom unit extension 112B, and a lateral unit extension 112C (i.e., three connection portions associated with the degassing unit 112). The lateral unit extension 112C can extend from the side of the degassing unit 112 at a location between the top unit extension 112A and the bottom unit extension 112B. The portion of the analytical system 100 prior to the central analytical device (not shown) can also be considered a fluid transfer system. In embodiments, the fluid transfer system can be a remote sample preparation and delivery system.

[0015] The at least one first valve 102 can be fluidically coupled to the top unit extension 112A of the degassing unit 112 via a second fluid line 118B (i.e., an upper fluid connection relative to the degassing unit 112). The at least one first valve 102 can be configured to selectively connect the degassing unit 112 to a replacement gas flow or a vacuum source. The degassing unit 112 can be separately and selectively coupled to the at least one second valve 104 using a third fluid line 118C (i.e., a lateral, central fluid connection relative to the degassing unit 112) via the lateral unit extension 112C, and using a fourth fluid line 118D (i.e., a lower fluid connection relative to the degassing unit 112) via the bottom unit extension 112B. The at least one second valve 104 can be fluidically coupled to the sample inlet 114 and to the at least one third valve 106 (e.g., via the latter connection of the fifth fluid line 118E). At least one second valve 104 can be selectively coupled to at least one of a sample-carrying fluid source, a transmission line configured to transport the sample to an analytical device, or a second waste output. The second waste outlet 116B can be selectively connected to at least one third valve 106 for establishing a selectable fluid connection with the at least one second valve 104. In an embodiment, according to the illustrated embodiment, at least one first valve 102, at least one second valve 104 and / or at least one third valve 106 can each be in the form of a multi-port valve. In an embodiment, the at least one first valve 102, at least one second valve 104 and / or at least one third valve 106 used herein can, for example, be pneumatically and / or electrically controlled and / or can be in the form of a distribution manifold. In an embodiment, at least one first valve 102, at least one second valve 104 and / or at least one third valve 106 can also be in the form of a mass flow controller (MFC) that can achieve electronically selective flow control therethrough. In an embodiment, the at least one first valve 102 , the at least one second valve 104 , and / or the at least one third valve 106 may be in the form of a plurality of valves (eg, instead of corresponding multi-port valves, for example).

[0016] According to an embodiment of the present disclosure, Figures 8 to 12 The operation of the analysis system 100 is illustrated in FIG. Figure 8 , the sample flow 120 (e.g., sample material in a carrier fluid (e.g., a carrier fluid containing ammonium hydroxide and / or another volatile component)) is directed into the bottom unit extension 112B and thereby through the degassing unit 112. The sample flow 120 (i.e., carrier fluid) can reach the bottom unit extension 112B via the sample inlet 114, the at least one second valve 104, and the fourth fluid line 118D. Further reference is made to Figure 8, the at least one first valve 102 can be configured to selectively direct a flow of nitrogen (i.e., N2) or another inert gas serving as a displacement gas into the top unit extension 112A via the second fluid line 118B, resulting in a quantity of N2 or other displacement gas being trapped under pressure at the top of the degassing unit 112. In embodiments, the displacement gas and the pressure provided thereby can prevent and / or delay the flow of the load fluid through the top unit extension 112A and toward the at least one first valve 102.

[0017] exist Figure 8 In the illustrated embodiment, the vacuum pump 108 is not fluidically connected to the degassing unit 112 (e.g., via the at least one first valve 102), and the sample flow 120 exiting the degassing unit 112 via the lateral unit extension 112C of the degassing unit can ultimately be directed to the second waste outlet 116B via the second valve 104 and the at least one third valve 106. That is, fluids (e.g., nitrogen / inert gas and sample flow) entering through the top and bottom of the degassing unit 112 can force some or all of such fluids to be expelled through the lateral unit extension 112C (i.e., the only available escape / release location). In embodiments, the degassing unit 112 can be partially or completely filled with carrier fluid before the replacement gas is introduced into the degassing unit 112. In embodiments, the flow rate of the replacement gas can be increased to help force any carrier fluid located at or above the third fluid line 118C out of the degassing unit 112 and ultimately toward the waste outlet 116B associated with the at least one third valve 106.

[0018] In the second step, as Figure 9 As shown, the flow connections remain the same, except that the sample flow 120 is shut off and the flow of N2 or other replacement gas continues. The continued flow of nitrogen increases the pressure of the sample remaining in the degassing unit 112, pushing any sample located at or above the third fluid line 118C from the degassing unit 112 to waste. Once the excess sample in the degassing unit 112 is pushed to waste, the sample is removed according to the flow diagram. Figure 9 , Figure 10 The flow combination shown in can then be activated. Figure 10 In the case of , the sample flow 120 from the sample inlet 114 remains closed, the flow through the at least one third valve 106 is opened toward the analysis device (not shown), and no longer flows through the second waste outlet 116B. Figure 10 , the N 2 / replacement gas flow is disconnected, wherein the degassing unit 112 is subjected to vacuum via the vacuum pump 108 via the at least one first valve 102 , and the fluid pulled by the vacuum pump 108 is directed to the first waste outlet 116A.

[0019] Figure 11 Maintained Figure 10The flow connections listed in , show the results. The flow dynamics facilitated by the vacuum can remove all liquid from the fourth fluid line 118D and remove ammonia (NH3) and / or other gases (e.g., ammonium hydroxide or other volatile components) from the sample stream 120. Due to the vacuum, Figure 11 Under such conditions, the sample stream 120 may actively generate bubbles, and the degassing unit 112 may feel cool during this step (e.g., as part of the heat exchange associated with the evaporation of ammonia and / or other gases).

[0020] Finally, according to Figure 12 At the steps shown, the degassing unit 112 can be reconnected to the flow of N2 / replacement gas (e.g., via the first valve 102 or the at least one second valve 104), disconnected from the vacuum flow, and disconnected from the at least one third valve 106. Additionally, flow to the transfer line 122 to the central analytical device (not shown) can be opened at the at least one second valve 104. As a result, the pressure from the N2 / replacement gas flow can push the sample, now free of or substantially free of ammonia / ammonium hydroxide and / or other volatile components (at least not enough to create any voids), as sample stream 120 through the fourth fluid line 118D, into the at least one second valve 104, and into the transfer line 122. The portion of the system 100 capable of delivering to the transfer line 122 and the central analytical device can be considered a remote flow processing system.

[0021] In embodiments, after loading the sample into the analysis system 100, the ammonium hydroxide sample can be properly degassed within approximately seven (7) minutes before being transferred for analysis. In some embodiments, after degassing, it was found that it was not necessary to allow the sample to rest in the loop, unlike without degassing. Other samples containing other volatile materials may require different lengths of time to degas. Without degassing, the sample must be allowed to rest in the loop to maintain the ICPMS plasma in a cool plasma state. After degassing the ammonium hydroxide sample using the present system, no obvious voids may be seen in the analysis loop after transfer. During degassing, some small NH4OH and / or NH3 bubbles may still form, but to an extent that does not appear to affect the test (i.e., substantially all of the ammonia is removed before analysis, at least to the extent that the remaining ammonia / ammonium hydroxide does not interfere with the test), at which point the sample can be considered to be sufficiently degassed. In embodiments, an upgrade kit for remote transfer using two valves and a vacuum pump is within the scope of the present system, and all components can be installed into existing blanks on the remote fluid handling system.

[0022] In embodiments, the analytical system 100 (e.g., implemented as an upgrade kit) can be used for thinner samples or for other samples that may warrant degassing (e.g., not just ammonia-based samples, but also, for example, when employing any potentially volatile (i.e., high vapor pressure) sample carrier). In embodiments, it should be understood that the present system can be used in any analytical system in which degassing of the sample may be necessary to prevent void formation. In embodiments, a suitable gas (e.g., an inert gas) can be used as a displacement gas to replace the nitrogen in the embodiments discussed herein. In some embodiments, the sample can be heated (e.g., prior to entering the analytical system 100 and / or at the degassing unit 112) to facilitate degassing. In embodiments, the sample can be cooled at the central receiving point, particularly if the sample is explicitly heated to facilitate degassing.

[0023] In an embodiment, a system controller (not shown) is a device that can be used to control the operation (e.g., valve and / or vacuum operation; and / or any related flow input) of the analysis system 100. The system controller may include a processor, a memory, and a communication interface. In an embodiment, the analysis system 100 may include one or more sensors (e.g., flow sensors, pressure sensors, etc.) that can work together with the system controller as needed to achieve the desired function of the system. The processor provides processing functionality for at least the controller and may include any number of processors, microcontrollers, circuits, field programmable gate arrays (FPGAs), or other processing systems, as well as resident or external memory for storing data, executable code, and other information accessed or generated by the controller. The processor may execute one or more software programs implemented in a non-transitory computer-readable medium that implement the technology described herein. The processor is not limited by the material from which it is formed or the processing mechanism employed therein, and may be implemented via semiconductors and / or transistors (e.g., using electronic integrated circuit (IC) components).

[0024] The memory may be an example of a tangible, computer-readable storage medium that provides storage functionality to store various data and / or program codes associated with the operation of the controller, such as software programs and / or code segments, or other data to instruct the processor and possibly other components of the system 100 to perform the functions described herein. Thus, the memory may store data, such as instruction programs for operating the system 100 (including its components), etc. It should be noted that although a single memory is described, a wide variety of types and combinations of memories (e.g., tangible, non-transitory memories) may be employed. The memory may be integral to the processor, may include a separate memory, or may be a combination of both.

[0025] Some examples of memory may include removable and non-removable memory components, such as random access memory (RAM), read-only memory (ROM), flash memory (e.g., secure digital (SD) memory card, mini SD memory card, and / or micro SD memory card), magnetic memory, optical memory, universal serial bus (USB) storage, hard disk storage, external storage, removable (e.g., server and / or cloud) storage, etc. In an embodiment, the memory may include removable integrated circuit card (ICC) memory, such as memory provided by a subscriber identity module (SIM) card, a universal subscriber identity module (USIM) card, a universal integrated circuit card (UICC), etc.

[0026] The communication interface can be operatively configured to communicate with components of the system 100. For example, the communication interface can be configured to transfer data for storage by the system 100, retrieve data from storage of the system 100, and the like. The communication interface can also be communicatively coupled to the processor to facilitate data transfer between components of the system 100 and the processor. It should be noted that while the communication interface is described as a component of the controller, one or more components of the communication interface can be implemented as external components communicatively coupled to the system 100 or its components via wired and / or wireless connections. The system 100 or its components can also include one or more input / output (I / O) devices and / or be connected (e.g., via the communication interface) to one or more input / output (I / O) devices, such as a display, a mouse, a touchpad, a touch screen, a keyboard, a microphone (e.g., for voice commands), and the like.

[0027] The communication interface and / or the processor can be configured to communicate with a variety of different networks, such as a wide-area cellular telephone network, for example, a cellular network, a 3G cellular network, a 4G cellular network, a 5G cellular network, or a Global System for Mobile Communications (GSM) network; a wireless computer communication network, such as a WiFi network (e.g., a wireless local area network (WLAN) operating using the IEEE 802.11 network standard); a dedicated wireless network, the Internet; a wide area network (WAN); a local area network (LAN); a personal area network (PAN) (e.g., a wireless personal area network (WPAN) operating using the IEEE 802.15 network standard); a public telephone network; an extranet; an intranet, and the like. However, this list is provided by way of example only and is not intended to limit the present disclosure. Furthermore, the communication interface can be configured to communicate with a single network or multiple networks across different access points. In a specific embodiment, the communication interface can transmit information from the controller to an external device (e.g., a cell phone, a computer connected to a WiFi network, cloud storage, etc.). In another specific embodiment, the communication interface can receive information from an external device (e.g., a cell phone, a computer connected to a WiFi network, cloud storage, etc.).

[0028] Although the subject matter has been described in language specific to structural features and / or methodological acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

1. A fluid transmission system comprising: a degassing unit oriented to define a top unit extension, a bottom unit extension, and a side unit extension, the side unit extension extending from a side of the degassing unit at a location between the top unit extension and the bottom unit extension; at least one first valve fluidly coupled to the top unit extension, the at least one first valve configured to selectively connect the degassing unit to a replacement gas flow or a vacuum source; as well as At least one second valve is fluidly connected to the lateral unit extension and separately connected to the bottom unit extension, and the at least one second valve is selectively coupled to at least one of a sample-carrying fluid source, a transfer line configured to transport the sample to an analytical device, or a waste output.

2. The fluid transmission system according to claim 1, characterized in that The at least one second valve is configured to provide a flow of carrier fluid to the degassing cell via the bottom cell extension, and the at least one first valve is configured to selectively provide a flow of replacement gas into the top cell extension when the carrier fluid is introduced into the degassing cell.

3. The fluid transmission system according to claim 2, characterized in that The at least one second valve is optionally configured to receive a flow of carrier fluid from a lateral cell extension of the degassing cell and direct the received carrier fluid to the waste output, the received carrier fluid being pushed out of the lateral cell extension by a flow of replacement gas entering the top cell extension.

4. The fluid transfer system of claim 3, further comprising at least one third valve configured to selectively fluidly interconnect the at least one second valve with the waste output.

5. The fluid transmission system according to claim 3, characterized in that: The at least one third valve is further optionally configured to stop directing the flow of the carrier fluid from the lateral unit extension to the waste output when the level of the carrier fluid in the degassing unit drops below the position of the fluid interconnect extending between the lateral unit extension and the at least one second valve.

6. The fluid transmission system according to claim 1, wherein: The at least one first valve is configured to be selectively connected to a vacuum source configured to degas the carrier fluid when the degassing unit is filled with the carrier fluid at or below the location of the fluid interconnection extending between the lateral unit extension and the at least one second valve.

7. The fluid transmission system according to claim 6, characterized in that The vacuum source is fluidly connected to the second waste outlet.

8. The fluid transmission system according to claim 6, characterized in that The at least one first valve is configured to be selectively connected to the replacement gas flow when the carrier fluid is degassed, and the at least one second valve is configured at this stage to direct the degassed carrier fluid to a transfer line for a central analytical device.

9. The fluid transfer system according to claim 8, wherein: The displacement gas flow is sufficient to push the degassed carrier fluid out of the bottom unit extension and toward the transfer line.

10. The fluid transfer system according to claim 1, wherein: The at least one first valve is optionally configured to be connected to a source of nitrogen gas, with nitrogen gas serving as the displacement gas.

11. The fluid transfer system according to claim 1, wherein: At least one of the at least one first valve, the at least one second valve, or the at least one third valve, respectively, comprises a multi-port valve.

12. A fluid transfer process comprising: A fluid transfer system is provided, comprising a degassing unit, at least one first valve, and at least one second valve, the degassing unit being oriented to define a top unit extension, a bottom unit extension, and a lateral unit extension, the lateral unit extension extending from a side of the degassing unit at a location between the top unit extension and the bottom unit extension, the at least one first valve being fluidly coupled to the top unit extension, the at least one second valve being fluidly connected to the lateral unit extension via a lateral fluid connector and separately fluidly connected to the bottom unit extension; providing a flow of a load fluid through the bottom unit extension into the degassing unit; as well as When the flow of carrier fluid starts entering the degassing cell, a flow of replacement gas is introduced into the degassing cell via the top cell extension, which prevents any escape of carrier fluid through the top cell extension and towards the at least one first valve.

13. The fluid transfer process according to claim 12, characterized in that: The carrier fluid is provided to a liquid level above a lateral fluid connector extending from the lateral unit extension to the at least one second valve, the flow of carrier fluid being stopped when the liquid level above the lateral fluid connector is reached, the lateral fluid connector then being selectively connected to a first waste outlet via the at least one second valve, the flow of displacement gas pushing any carrier fluid at or above the lateral fluid connector into the lateral flow connector and ultimately toward the first waste outlet associated with the at least one second valve.

14. The fluid transfer process of claim 13, further comprising ceasing to direct the carrier fluid to the waste outlet when the level of the carrier fluid drops below the lateral fluid connector.

15. The fluid transfer process according to claim 14 further includes selectively connecting the at least one first valve to a vacuum source instead of to a flow of replacement gas so as to generate a vacuum pressure in the degassing unit, which promotes degassing of the sample-carrying fluid.

16. The fluid transfer process according to claim 15, characterized in that: The carrier fluid includes ammonium hydroxide, and upon application of the vacuum pressure, a gas including at least one of ammonium hydroxide or ammonia is degassed from the carrier fluid.

17. The fluid transfer process according to claim 15, characterized in that: After degassing the carrier fluid, replacement gas is again supplied to the degassing unit via the at least one first valve, and the flow through the at least one second valve is redirected to the transfer line for the analytical device.

18. The fluid transfer process according to claim 17, characterized in that: The displacement gas flow is sufficient to push the degassed carrier fluid out of the bottom unit extension and toward the transfer line.

19. The fluid transfer process according to claim 12, wherein: The at least one first valve is optionally configured to be connected to a source of nitrogen gas, with nitrogen gas serving as the displacement gas.

20. The fluid transfer process according to claim 12, wherein: At least one of the at least one first valve, the at least one second valve, or the at least one third valve, respectively, comprises a multi-port valve.

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