Rapid Desorber Heating and Cooling for Trace Detection
A desorber for a trace detection system. The desorber includes an inlet configured to receive a sample, a heating element configured to generate a vapor from the sample, and an active cooling element configured to cool the desorber.
The present application is a continuation application of U.S. patent application Ser. No. 15/476,616, entitled “RAPID DESORBER HEATING AND COOLING FOR TRACE DETECTION” and filed on Mar. 31, 2017, which is herein incorporated by reference in its entirety.
BACKGROUNDThe field of the disclosure relates generally to trace detection systems and, more particularly, to a rapid-cooled desorber of a trace detection system.
Various technologies exist for detection of certain substances of interest, such as explosives and illicit drugs. Some trace detection technologies use spectrometric analysis of ions formed by ionization of vapors of substances of interest. Spectrometric analysis includes ion mobility spectrometry and mass spectrometry, for example, both of which are common in trace detection.
Trace detection systems analyze a sample to screen for a substance. The sample may be introduced to the system at an inlet, such as an inlet of a desorber, where the sample is rapidly heated to a desired temperature by a heating element to vaporize the sample. The vapor is then transferred to an analysis device or a detector for spectrometric analysis where it is screened for the substance of interest. When the desorber is cooled to a desired temperature, the trace detection system is ready for a subsequent sample to be introduced at the inlet for analysis.
BRIEF DESCRIPTIONIn one aspect, a desorber is provided. The desorber includes an inlet, a heating element, and an active cooling element. The inlet is configured to receive a sample. The heating element is configured to generate a vapor from the sample. The active cooling element is configured to cool the desorber.
In another aspect, a method of operating a trace detection system for detecting a substance of interest within a sample is provided. The method includes receiving a first sample at an inlet of a desorber. The method includes heating, by a heating element, the desorber to a first temperature to release a vapor from the first sample. The method includes transferring the vapor from the desorber to an analysis device configured to screen the vapor for the substance of interest. The method includes cooling the desorber to at least a second temperature. The method includes receiving a second sample at the inlet of the desorber.
In yet another aspect, a system for detecting a substance of interest within a sample is provided. The system includes a desorber and an analysis device. The desorber is configured to release a vapor from the sample, wherein the desorber includes an inlet configured to receive the sample, a heating element configured to release the vapor from the sample, and an active cooling element configured to cool the desorber. The analysis device is configured to screen the vapor for the substance of interest
These and other features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:
Unless otherwise indicated, the drawings provided herein are meant to illustrate features of embodiments of this disclosure. These features are believed to be applicable in a wide variety of systems comprising one or more embodiments of this disclosure. As such, the drawings are not meant to include all conventional features known by those of ordinary skill in the art to be required for the practice of the embodiments disclosed herein.
DETAILED DESCRIPTIONIn the following specification and the claims, a number of terms are referenced that have the following meanings.
The singular forms “a,” “an,” and “the” include plural references unless the context clearly dictates otherwise.
“Optional” or “optionally” means that the subsequently described event or circumstance may or may not occur, and that the description includes instances where the event occurs and instances where it does not.
Approximating language, as used herein throughout the specification and claims, may be applied to modify any quantitative representation that could permissibly vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about,” “approximately,” and “substantially,” are not to be limited to the precise value specified. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value. Here and throughout the specification and claims, range limitations may be combined and/or interchanged. Such ranges are identified and include all the sub-ranges contained therein unless context or language indicates otherwise.
Conventional trace detection systems that require sample heating, such as in a desorber, may have limited sample throughput (i.e., the number of samples that can be analyzed in a given period of time) due to the time needed to cool the desorber enough to accept a subsequent sample. Different substances vaporize at different temperatures. Accordingly, depending on the phase and volatility of a substance of interest within a sample, the sample may require little to no heating (e.g., gaseous and/or high volatility substances), heating up to 100° C. (e.g., volatile explosives), heating up to 240° C. (e.g., conventional explosives), heating up to 380° C. (e.g., inorganic salts or homemade explosives), or heating above 380° C. (e.g., solid and/or low volatility substances). If the initial temperature of the desorber is too high when a sample is received at the inlet, the substance of interest in the sample will decompose and may not be detected at all, thus reducing system detection accuracy and performance. Providing an appropriately low initial temperature of the desorber is necessary to enable the trace detection system to accurately detect a wide range of illicit substances within a sample. Consequently, even when sample heating and detection steps occur rapidly, long lag times (e.g., 6 minutes or more) between samples due to slow desorber cooling significantly limits the throughput capabilities of the system.
It is realized herein it is important to actively and rapidly cool a desorber of a trace detection system for effective high throughput operation of the system. For example, an exemplary trace detection system used at an airport or other location where preferred time between samples is low and sample volume is high would require high throughput for detection of explosive substances. In addition, such a system would be required to accurately detect a wide range of substances. Accordingly, in order for a system to successfully and consistently vaporize various substances of interest at different temperatures within a reasonably short cycle time, an active cooling element for cooling the desorber is needed to reset the system for each subsequent sample.
Embodiments of the desorbers described herein enable active and rapid cooling of the desorbers. The desorber itself may have various forms and compositions for different systems and analysis, such as an internal cooling element, an external cooling element, or both. More specifically, the desorbers described herein incorporate at least one active cooling element configured to rapidly cool the desorber (e.g., by forced convection). In some embodiments, the desorber includes an internal cooling element configured to cool an internal portion of the desorber. In other embodiments, the desorber includes an external cooling element configured to cool an external portion of the desorber. In some embodiments, the desorber includes both internal and external cooling elements that may operate sequentially or simultaneously to achieve a desired target cooling rate and/or target temperature. An active cooling element may include fans, high volume pumps, liquid and gas coolants, thermal electric coolers, refrigeration cycles, and combinations thereof, for example. The active rapid desorber cooling described herein enables throughput cycle time to be substantially reduced, for example, down to 2 minutes or less, 1 minute or less, or 30 seconds or less. Accordingly, use of such specialized actively-cooled desorbers enhances sample throughput capabilities of a trace detection system.
Trace detection systems that embody the desorbers described herein may further include a control system, processor, or other computing device for operating the cooling element to enable rapid and active cooling of the desorber, such as, for example, simultaneous or sequential operation of internal and external cooling elements.
Desorber 100 further includes cooling element 206. Cooling element 206 may embody one or more active cooling elements configured to cool the desorber. For example, cooling element 206 may be configured to cool the desorber using forced convection. Cooling element 206 may be an internal cooling element configured to cool an internal portion of the desorber. An internal portion of the desorber 100 may include any portion in which sample 202 is contained, heated, and/or vaporized within the desorber 100. Cooling element 206 may be an external cooling element configured to cool an external portion of the desorber 100 and may, in some embodiments, be integrated into housing 106 of desorber 100. An external portion of the desorber 100 may include any portion outside of which sample 202 is contained, heated, and or vaporized. In some embodiments, desorber 100 may include both internal and external cooling elements 206. In certain embodiments when both internal and external cooling elements 206 are present, they may operate simultaneously or sequentially, depending on the cooling requirements for the desorber and desired sample cycle time, for example. Cooling element 206 may include at least one of a fan, a high-volume pump, a thermal electric cooler, a compressed gas, a liquid coolant, a gas coolant, an active refrigeration cycle, a compression refrigeration cycle, and an absorption refrigeration cycle.
As an example, a desorber 100 may include a high volume pump as the internal cooling element as well as a fan integrated into housing 106 as the external cooling element. Continuing with this example, the high volume pump and/or the fan may utilize un-treated or pre-treated (such as cooled and/or cleaned) ambient air. Alternatively, internal cooling using the high volume pump may utilize doped air, an inert gas, pre-treated air, or combinations thereof, for example.
In some embodiments, cooling element 206 may be a closed-loop, recirculating system. In certain embodiments when cooling element 206 is a recirculating system, desorber 100 may also include a heat exchanger (not shown). The heat exchanger may be coupled to (i.e., in thermal communication with) the active cooling element and configured to transfer heat from the active cooling element. For example, in embodiments where the active cooling element includes a liquid coolant, heat exchanger may transfer heat from the liquid coolant so that the coolant may be recirculated to cool the desorber within a single sample cycle or in a subsequent sample cycle.
Substances of interest may include at least one of an explosive, an energetic material, a taggant, a narcotic, a pharmaceutical product, a toxin, a chemical warfare agent, a biological warfare agent, a pollutant, a pesticide, a toxic industrial chemical, a toxic industrial material, a homemade explosive, a pharmaceutical trace contaminant, a biomarker for medical applications, a chemical marker for medical applications, a biomarker for clinical hygienic applications, a chemical marker for clinical hygienic applications, a precursor thereof, a byproduct thereof, a metabolite thereof, and combinations thereof.
In trace detection system 600, analysis device 602 may include at least one of an ion mobility spectrometer (IMS), an ion trap mobility spectrometer (ITMS), a drift spectrometer (DS), a non-linear drift spectrometer, a field ion spectrometer (FIS), a radio frequency ion mobility increment spectrometer (IMIS), a field asymmetric ion mobility spectrometer (FAIMS), an ultra-high-field FAIMS, a differential ion mobility spectrometer (DIMS) and a differential mobility spectrometer (DMS), a traveling wave ion mobility spectrometer, a semiconductor gas sensor, a raman spectrometer, a laser diode detector, a mass spectrometer (MS), an electron capture detector, a photoionization detector, a chemiluminescence-based detector, an electrochemical sensor, an infrared spectrometer, a lab-on-a-chip detector, and combinations thereof.
An exemplary technical effect of the methods, systems, and apparatus described herein includes at least one of: (a) increasing sample throughput capabilities of a trace detection system by significantly decreasing cycle times between samples; (b) preventing decomposition and/or loss of subsequent samples resulting from excessive initial desorber temperature; (c) improving analysis sensitivity through identification of substances of interest having widely varying vaporization temperatures; and (d) increasing overall system performance and efficiency by accurately and rapidly identifying a wide range of substances of interest.
Exemplary embodiments of methods, systems, and apparatus for desorbers are not limited to the specific embodiments described herein, but rather, components of systems and/or steps of the methods may be utilized independently and separately from other components and/or steps described herein. For example, the methods may also be used in combination with other non-conventional desorbers and trace detection systems, and are not limited to practice with only the systems and methods as described herein. Rather, the exemplary embodiment can be implemented and utilized in connection with many other applications, equipment, and systems that may benefit from increased efficiency, reduced operational cost, and reduced capital expenditure.
Although specific features of various embodiments of the disclosure may be shown in some drawings and not in others, this is for convenience only. In accordance with the principles of the disclosure, any feature of a drawing may be referenced and/or claimed in combination with any feature of any other drawing.
Some embodiments involve the use of one or more electronic or computing devices. Such devices typically include a processor or controller, such as a general purpose central processing unit (CPU), a graphics processing unit (GPU), a microcontroller, a reduced instruction set computer (RISC) processor, an application specific integrated circuit (ASIC), a programmable logic circuit (PLC), and/or any other circuit or processor capable of executing the functions described herein. The methods described herein may be encoded as executable instructions embodied in a computer readable medium, including, without limitation, a storage device and/or a memory device. Such instructions, when executed by a processor, cause the processor to perform at least a portion of the methods described herein. The above examples are exemplary only, and thus are not intended to limit in any way the definition and/or meaning of the term processor.
This written description uses examples to disclose the embodiments, including the best mode, and also to enable any person skilled in the art to practice the embodiments, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the disclosure is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.
Claims
1. A desorber, comprising:
- an inlet configured to receive a sample;
- a heating element configured to generate a vapor from the sample; and
- an active cooling element configured to cool the desorber.
2. The desorber of claim 1, wherein the heating element is a flash heater.
3. The desorber of claim 1, wherein the active cooling element is at least one of a fan, a high-volume pump, a thermal electric cooler, a compressed gas, a liquid coolant, a gas coolant, an active refrigeration cycle, a compression refrigeration cycle, and an absorption refrigeration cycle.
4. The desorber of claim 1, wherein the active cooling element comprises at least one of an internal cooling element configured to cool an internal portion of the desorber and an external cooling element configured to cool an external portion of the desorber.
5. The desorber of claim 4, wherein the active cooling element comprises both the internal cooling element and the external cooling element.
6. The desorber of claim 4, wherein at least one of the internal cooling element and the external cooling element is a recirculating system.
7. The desorber of claim 1, further comprising a heat exchanger coupled to the active cooling element and configured to transfer heat from the active cooling element.
8. A method of operating a trace detection system for detecting a substance of interest within a sample, the method comprising:
- receiving a first sample at an inlet of a desorber;
- heating, by a heating element, the desorber to a first temperature to release a vapor from the first sample;
- transferring the vapor from the desorber to an analysis device configured to screen the vapor for the substance of interest;
- actively cooling the desorber to at least a second temperature; and
- receiving a second sample at the inlet of the desorber.
9. The method of claim 8, wherein actively cooling the desorber comprises cooling using forced convection.
10. The method of claim 8, wherein actively cooling the desorber comprises cooling an internal portion of the desorber using an internal cooling element.
11. The method of claim 8, wherein actively cooling the desorber comprises cooling an external portion of the desorber using an external cooling element.
12. The method of claim 8, wherein actively cooling the desorber comprises simultaneously cooling an internal portion of the desorber using an internal cooling element and cooling an external portion of the desorber using an external cooling element.
13. The method of claim 8, wherein the first temperature is higher than the second temperature.
14. The method of claim 8, wherein heating the desorber to a first temperature comprises heating the desorber in a plurality of stages to reach the first temperature and vaporize the sample.
15. The method of claim 8, wherein actively cooling the desorber comprises cooling the desorber in a plurality of stages to reach the second temperature.
16. The method of claim 8, wherein a time between receiving the first sample and receiving the second sample is 30 seconds or less.
17. The method of claim 8, wherein a time between receiving the first sample and receiving the second sample is from 30-120 seconds.
18. A system for detecting a substance of interest within a sample, the system comprising:
- a desorber configured to release a vapor from the sample, wherein the desorber comprises an inlet configured to receive the sample, a heating element configured to release the vapor from the sample, and an active cooling element configured to cool the desorber; and
- an analysis device configured to screen the vapor for the substance of interest.
19. The system of claim 18, wherein the substance of interest includes at least one of an explosive, an energetic material, a taggant, a narcotic, a pharmaceutical product, a toxin, a chemical warfare agent, a biological warfare agent, a pollutant, a pesticide, a toxic industrial chemical, a toxic industrial material, a homemade explosive, a pharmaceutical trace contaminant, a biomarker for medical applications, a chemical marker for medical applications, a biomarker for clinical hygienic applications, a chemical marker for clinical hygienic applications, a precursor thereof, a byproduct thereof, a metabolite thereof, and combinations thereof.
20. The system of claim 18, wherein the analysis device includes at least one of an ion mobility spectrometer (IMS), an ion trap mobility spectrometer (ITMS), a drift spectrometer (DS), a non-linear drift spectrometer, a field ion spectrometer (FIS), a radio frequency ion mobility increment spectrometer (IMIS), a field asymmetric ion mobility spectrometer (FAIMS), an ultra-high-field FAIMS, a differential ion mobility spectrometer (DIMS) and a differential mobility spectrometer (DMS), a traveling wave ion mobility spectrometer, a semiconductor gas sensor, a raman spectrometer, a laser diode detector, a mass spectrometer (MS), an electron capture detector, a photoionization detector, a chemiluminescence-based detector, an electrochemical sensor, an infrared spectrometer, a lab-on-a-chip detector, and combinations thereof.
Type: Application
Filed: Sep 20, 2019
Publication Date: Apr 9, 2020
Inventors: Bradley Douglas Shaw (Plaistow, NH), Dung Lu (Malden, MA), Stephen L. Crook (Reading, MA), Karl Goedecke (Everett, MA), Hanh T. Lai (Arlington, MA), Vladimir Romanov (Pelham, NH)
Application Number: 16/577,777