Triple point immersion cell article

Patent metadata

Field	Value
Publication number	US-11204288-B2
Application number	US-201916567765-A
Country	US
Kind code	B2
Filing date	Sep 11, 2019
Priority date	Sep 11, 2019
Publication date	Dec 21, 2021
Grant date	Dec 21, 2021

Abstract

A triple point immersion cell article determines a triple point of a non-metallic analyte and includes: a first cryochamber including a first cryo-zone; a second cryochamber including a second cryo-zone that is: nested and disposed in the first cryochamber; and thermally isolated by the first cryochamber; a third cryochamber including a third cryo-zone, the third cryochamber being: nested and disposed in the second cryochamber; thermally isolated from the exterior environment by the first cryochamber and the second cryochamber; and thermally isolated from the first cryochamber by the second cryochamber; and a fourth cryochamber including a fourth cryo-zone disposed in the third cryochamber; a triple-point pressure vessel disposed in the fourth cryochamber; and a thermowell disposed in the triple-point pressure vessel.

First claim

What is claimed is:

1. A triple point immersion cell article for determining a triple point of a non-metallic analyte, the triple point immersion cell article comprising:
a first cryochamber comprising a first cryo-zone;
a second cryochamber comprising a second cryo-zone, the second cryochamber being:
nested and disposed in the first cryochamber; and
thermally isolated from an exterior environment of the triple point immersion cell article by the first cryochamber;

a third cryochamber comprising a third cryo-zone, the third cryochamber being:
nested and disposed in the second cryochamber;
thermally isolated from the exterior environment by the first cryochamber and the second cryochamber; and
thermally isolated from the first cryochamber by the second cryochamber; and

a fourth cryochamber comprising a fourth cryo-zone, the fourth cryochamber being:
nested and disposed in the third cryochamber;
thermally isolated from the exterior environment by the first cryochamber, the second cryochamber, and the third cryochamber; and
thermally isolated from the second cryochamber by the third cryochamber; and
a triple-point pressure vessel comprising a fifth cryo-zone, the triple-point pressure vessel being:
nested and disposed in the fourth cryochamber;
thermally isolated from the exterior environment by the first cryochamber, the second cryochamber, the third cryochamber, and the fourth cryochamber; and
thermally isolated from the third cryochamber by the fourth cryochamber; and

a thermowell disposed in the triple-point pressure vessel, the triple-point pressure vessel being directly accessible from the exterior environment via thermowell.

2. The triple point immersion cell article of claim 1 , further comprising a first cryocooler in thermal communication with the first cryochamber.

3. The triple point immersion cell article of claim 2 , wherein the first cryocooler actively cools the first cryochamber to produce the first cryo-zone.

4. The triple point immersion cell article of claim 2 , wherein the first cryocooler comprises a Stirling cycle cryocooler.

5. The triple point immersion cell article of claim 1 , further comprising a second cryocooler in thermal communication with the second cryochamber.

6. The triple point immersion cell article of claim 5 , wherein the second cryocooler actively cools the second cryochamber to produce the second cryo-zone.

7. The triple point immersion cell article of claim 5 , wherein the second cryocooler comprises a Stirling cycle cryocooler.

8. The triple point immersion cell article of claim 1 , wherein the first cryo-zone and the second cryo-zone are subjected to closed-cycle refrigeration in an absence of a liquid cryogen.

9. The triple point immersion cell article of claim 1 , wherein the fourth cryo-zone is an adiabatic zone with respect to a triple point transition temperature of non-metallic analyte.

10. The triple point immersion cell article of claim 1 , wherein the first cryochamber, the second cryochamber, the third cryochamber, and the fourth cryochamber are reversibly demountable and re-mountable from one another.

11. The triple point immersion cell article of claim 1 , wherein the triple-point pressure vessel accommodates a fixed point of the non-metallic analyte from 75 K to 175 K.

12. The triple point immersion cell article of claim 1 , wherein the fourth cryo-zone provides a stable and reproducible melt plateau for the non-metallic analyte.

13. The triple point immersion cell article of claim 1 , wherein the non-metallic analyte comprises a rare gas condensate.

14. The triple point immersion cell article of claim 1 , wherein the triple-point pressure vessel and triple-point cell interior volume receive a long-stem thermometer or capsule-type thermometer for calibration at the triple point of the non-metallic analyte.

15. The triple point immersion cell article of claim 1 , wherein a pressure of the first cryochamber, the second cryochamber, the third cryochamber, and the fourth cryochamber is high-vacuum.

16. The triple point immersion cell article of claim 1 , wherein the first cryo-zone, the second cryo-zone, the third cryo-zone, and the fourth cryo-zone are subjected to active control.

17. The triple point immersion cell article of claim 1 , further comprising a thermowell with a length that is from 10 cm to 100 cm to receive a long-stem thermometer,
wherein the thermowell is in thermal communication with the first cryo-zone, the second cryo-zone, the third cryo-zone, and the fourth cryo-zone and in mechanical communication with the first cryochamber, the second cryochamber, the third cryochamber, the fourth cryochamber, the triple-point pressure vessel, the triple-point cell interior volume, and the thermowell receiving helium as a heat exchange gas at a pressure from 1 millibar (mbar) to 1.3 bar.

18. The triple point immersion cell article of claim 1 , further comprising a vacuum chamber housing disposed around the first cryochamber.

19. A process for determining a triple point of a non-metallic analyte with the triple point immersion cell article of claim 1 , the process comprising:
evacuating a vacuum chamber in which the first cryochamber is disposed;
cooling the first cryo-zone, the second cryo-zone, the third cryo-zone, and the fourth cryo-zone with a cryocooler;
flowing the non-metallic analyte into the triple point cell interior volume to partially condense the non-metallic analyte;
inserting an immersion cooler in the thermowell to complete condensation of the non-metallic analyte;
initiating freezing of the non-metallic analyte;
removing the immersion cooler;
introducing a calibrated standard platinum resistance thermometer into the thermowell;
flowing helium heat-exchange gas in the thermowell;
adjusting a set point temperature of each of the first cryochamber, the second cryochamber, the third cryochamber, and the fourth cryochamber to a selected value for the non-metallic analyte;
pulse heating of the triple point cell pressure vessel in energy increments;
adjusting a set point of the fourth cryo-zone to an adiabatic condition;
suspending pulse heating;
removing the calibrated standard platinum resistance thermometer;
disposing a test standard platinum resistance thermometer into thermowell;
removing the test standard platinum resistance thermometer from the thermowell;
re-disposing the calibrated standard platinum resistance thermometer in the thermowell;
resuming pulse melting;
completely melting the non-metallic analyte;
reinserting the immersion cooler into the thermowell; and
refreezing the non-metallic analyte to determine the triple point of the non-metallic analyte.

Assignees

• Government Of The Us Secretary Of Commerce

Inventors

• Tew Jr Weston Leo
• Nanninga Jay Robert

Classifications

• G01K1/16

  Special arrangements for conducting heat from the object to the sensitive element · CPC title

• G01K13/006 Primary

  for cryogenic purposes · CPC title

• G01N25/12

  of critical point; of other phase change · CPC title

• G01K11/06

  using melting, freezing, or softening · CPC title

• G01K2203/00

  Application of thermometers in cryogenics · CPC title