Method of producing nitrogen-depleted gas, method of producing nitrogen-enriched gas, method of nitrogen separation, and system of nitrogen separation

Patent metadata

Field	Value
Publication number	US-10449485-B2
Application number	US-201615287796-A
Country	US
Kind code	B2
Filing date	Oct 7, 2016
Priority date	Oct 9, 2015
Publication date	Oct 22, 2019
Grant date	Oct 22, 2019

Abstract

A nitrogen separation system includes a pressurizing apparatus, a temperature regulation apparatus, a nitrogen separation apparatus. The pressurizing apparatus is configured to pressurize a raw material gas to configure a pressurized raw material gas which is in a vapor-liquid equilibrium state with a liquefied gas and contains methane as a principal component and greater than or equal to 1 mol % nitrogen. The nitrogen separation apparatus is configured to separate nitrogen contained in the pressurized raw material gas by use of a nitrogen selective permeation membrane configured from an inorganic material. The pressurization apparatus pressurizes the raw material gas so that a partial pressure of nitrogen in the pressurized raw material gas is greater than or equal to 2 times and less than or equal to 5 times a pressure of the nitrogen-enriched gas.

First claim

The invention claimed is:

1. A method of producing a nitrogen-depleted gas, the method comprising the steps of:
pressurizing a raw material gas to configure a pressurized raw material gas, the raw material gas being in a vapor-liquid equilibrium state with a liquefied gas, the raw material gas containing methane as a principal component and greater than or equal to 1 mol % nitrogen;
regulating a temperature of the pressurized raw material gas to be higher than a temperature of the raw material gas; and
separating nitrogen contained in the pressurized raw material gas by use of a nitrogen selective permeation membrane configured from an inorganic material to produce a nitrogen-depleted gas and a nitrogen-enriched gas from the pressurized raw material gas; wherein
in the pressurization step, the raw material gas is pressurized so that a partial pressure of nitrogen in the pressurized raw material gas is greater than or equal to 2 times and less than or equal to 5 times a pressure of the nitrogen-enriched gas.

2. The method of producing a nitrogen-depleted gas according to claim 1 , wherein the temperature of the pressurized raw material gas is less than or equal to −40 degrees C.

3. The method of producing a nitrogen-depleted gas according to claim 1 , wherein the nitrogen selective permeation membrane is configured from a zeolite and/or a zeolite like structure compound selected from the group consisting of silicalites, aluminosilicates, titanosilicates, aluminophosphates, and silica aluminophosphates.

4. The method of producing a nitrogen-depleted gas according to claim 3 , wherein the zeolite and/or the zeolite like structure compound includes pores formed by an oxygen 8-membered ring.

5. A method of producing a nitrogen-enriched gas, the method comprising the steps of:
pressurizing a raw material gas to configure a pressurized raw material gas, the raw material gas being in a vapor-liquid equilibrium state with a liquefied gas, the raw material gas containing methane as a principal component and greater than or equal to 1 mol % nitrogen;
regulating a temperature of the pressurized raw material gas to be higher than a temperature of the raw material gas; and
separating nitrogen contained in the pressurized raw material gas by use of a nitrogen selective permeation membrane configured from an inorganic material to produce a nitrogen-depleted gas and a nitrogen-enriched gas from the pressurized raw material gas; wherein
in the pressurization step, the raw material gas is pressurized so that a partial pressure of nitrogen in the pressurized raw material gas is greater than or equal to 2 times and less than or equal to 5 times a pressure of the nitrogen-enriched gas.

6. The method of producing a nitrogen-enriched gas according to claim 5 , wherein the temperature of the pressurized raw material gas is less than or equal to −40 degrees C.

7. The method of producing a nitrogen-enriched gas according to claim 5 , wherein the nitrogen selective permeation membrane is configured from a zeolite and/or a zeolite like structure compound selected from the group consisting of silicalites, aluminosilicates, titanosilicates, aluminophosphates, and silica aluminophosphates.

8. The method of producing a nitrogen-enriched gas according to claim 7 , wherein the zeolite and/or the zeolite like structure compound includes pores formed by an oxygen 8-membered ring.

9. A method of nitrogen separation, the method comprising the steps of:
pressurizing a raw material gas to configure a pressurized raw material gas, the raw material gas being in a vapor-liquid equilibrium state with a liquefied gas, the raw material gas containing methane as a principal component and greater than or equal to 1 mol % nitrogen;
regulating a temperature of the pressurized raw material gas to be higher than a temperature of the raw material gas; and
separating nitrogen contained in the pressurized raw material gas by use of a nitrogen selective permeation membrane configured from an inorganic material to produce a nitrogen-depleted gas and a nitrogen-enriched gas from the pressurized raw material gas; wherein
in the pressurization step, the raw material gas is pressurized so that a partial pressure of nitrogen in the pressurized raw material gas is greater than or equal to 2 times and less than or equal to 5 times a pressure of the nitrogen-enriched gas.

10. The method of nitrogen separation according to claim 9 , wherein the temperature of the pressurized raw material gas is less than or equal to −40 degrees C.

11. The method of nitrogen separation according to claim 9 , wherein the nitrogen selective permeation membrane is configured from a zeolite and/or a zeolite like structure compound selected from the group consisting of silicalites, aluminosilicates, titanosilicates, aluminophosphates, and silica aluminophosphates.

12. The method of nitrogen separation according to claim 11 , wherein the zeolite and/or the zeolite like structure compound includes pores formed by an oxygen 8-membered ring.

Assignees

• Ngk Insulators Ltd

Inventors

• Noda Kenichi

Classifications

• C10L3/105

  of nitrogen · CPC title

• B01D2257/102

  Nitrogen · CPC title

• B01D2256/24

  Hydrocarbons · CPC title

• B01D53/22

  by diffusion (manufacturing semi-permeable membranes B01D67/00; form, structure or properties of semi-permeable membranes B01D69/00; material for semi-permeable membranes B01D71/00) · CPC title

• C10L2290/548

  Membrane- or permeation-treatment for separating fractions, components or impurities during preparation or upgrading of a fuel · CPC title