Method and system for generating vapors of liquid solutions

Patent metadata

Field	Value
Publication number	US-9597700-B2
Application number	US-201313926075-A
Country	US
Kind code	B2
Filing date	Jun 25, 2013
Priority date	Jun 27, 2012
Publication date	Mar 21, 2017
Grant date	Mar 21, 2017

Abstract

A method and system for generating vapors of liquid solutions where a pneumatically modulated liquid delivery system maintains a defined flow rate for a liquid solution. The pneumatically modulated liquid delivery system includes a flow meter configured to measure a flow rate for the liquid solution flowing from a pressure vessel; a microcontroller configured to determine a pressure necessary to achieve the defined flow rate; and an electronic pressure control unit configured to adjust the pressure inside the pressure vessel. The system includes a nebulizer coupled to the pneumatically modulated liquid delivery system configured to receive the liquid solution from the pneumatically modulated liquid delivery system at the defined flow rate and configured to generate an aerosol of the liquid solution. A heat tube can vaporize the aerosol generated by the nebulizer.

First claim

The invention claimed is:

1. A method for generating vapors from liquid solutions, comprising the steps of:
maintaining a defined flow rate for the liquid solution with a pneumatically modulated liquid delivery system;
delivering the liquid solution to a nebulizer at the defined flow rate;
generating an aerosol of the liquid solution with the nebulizer; and
vaporizing the aerosol in a heated tube,
wherein the step of maintaining the defined flow rate for the liquid solution with the pneumatically modulated liquid delivery system, comprises the steps of:
measuring a flow rate for the liquid solution flowing from a pressure vessel with a flow meter;
determining a pressure necessary to achieve the defined flow rate with a microcontroller; and
adjusting the pressure inside the pressure vessel with an electronic pressure control unit.

2. The method of claim 1 , wherein determining a pressure necessary to achieve the defined flow rate with the microcontroller, comprises the steps of:
recording the measured flow rate; and
calculating the pressure necessary to achieve the defined flow rate with a control algorithm.

3. The method of claim 1 , wherein the step of maintaining the defined flow rate for the liquid solution with the pneumatically modulated liquid delivery system is performed in a closed-loop feedback system.

4. The method of claim 1 , wherein the step of maintaining the defined flow rate for the liquid solution with the pneumatically modulated liquid delivery system is continuously repeated over a defined period of operation.

5. The method of claim 1 wherein the step of generating an aerosol of the liquid solution with the nebulizer comprises the step of passing a high-velocity sheath gas over an orifice of a capillary filled with low volatility liquid solution.

6. The method of claim 2 , wherein the control algorithm is a Proportional Integral Derivative control algorithm.

Assignees

• Field Christopher
• Terray Alexander V
• Hart Sean J
• Rogers Duane A
• Lubrano Adam
• Malito Michael P
• Us Navy

Inventors

• Field Christopher
• Terray Alexander V
• Hart Sean J
• Rogers Duane A
• Lubrano Adam
• Malito Michael P

Classifications

• H01J49/045 Primary

  with means for using a nebulising gas, i.e. pneumatically assisted · CPC title

• G01N21/714

  Sample nebulisers for flame burners or plasma burners (nebulizers per se B05B) · CPC title

• B05B12/087 Primary

  Flow or presssure regulators, i.e. non-electric unitary devices comprising a sensing element, e.g. a piston or a membrane, and a controlling element, e.g. a valve · CPC title