Methods and systems for distributing liquid chemicals

• US 6,168,048 B1
• Filed: 09/22/1998
• Issued: 01/02/2001
• Est. Priority Date: 09/22/1998
• Status: Expired due to Fees

• Current Assignee: American Air Liquide Incorporated (L'Air Liquide SA), L'Air Liquide Societe Anonyme Pour L'Etude et L'Exploitation Des Procedes Georges Claude (L'Air Liquide SA)
• Original Assignee: American Air Liquide Incorporated (L'Air Liquide SA)
• Inventors: Xu, Mindi, Vigor, Xavier
• Primary Examiner(s): Kaufman, Joseph A.
• Application Number:
  US09/158,740
• Time in Patent Office: 833 Days
• Field of Search: 222/1, 222/61, 222/64, 222/135, 222/189.06, 222/318, 222/386.5, 222/399
• US Class Current: 222/1
• CPC Class Codes: B67D 1/045 using elastic bags and pistons actuated by air or other gas
• CPC Class Codes: B67D 7/025 specially adapted for transferring liquids of high purity
• CPC Class Codes: Y02E 60/34 Hydrogen distribution

Abstract

Briefly, this invention uses one or more pressure vessels having installed therein on its inside a balloon of flexible and non-expandable wall to smoothly and continuously deliver a chemical to any end user without contamination and gas dissolution. Since the balloon installed inside the pressure vessel isolates a high pressure gas from the chemicals, gas dissolution in the chemical and the resulted gas bubble problems are effectively eliminated. Further, contaminants in the high pressure gas which fills the balloon will not be transferred into the chemical and the extremely toxic chemical will not be transferred into the gas to be exhausted as a serious environmental issue. Unlike the vacuum/pressure system, the contamination by the ambient air leaking into the system is avoided because the disclosed delivery system is always with the pressure higher or equal to the ambient pressure.

Claims

1. A system for transferring and delivering a liquid chemical from a bulk source to an end use station, the system comprising:

(a) a pressure vessel connected to the bulk source by a delivery conduit, the pressure vessel having an internal surface, the delivery conduit having a pump therein;

(b) a balloon positioned within the pressure vessel, the balloon having an interior and an interior surface and an exterior and an exterior surface;

(c) a space adapted to receive liquid chemical, the space defined by at least a portion of the balloon exterior surface and at least a portion of the pressure vessel internal surface; and

(d) means for delivering a pressurized gas into the balloon, whereby upon entrance of the gas into the balloon, the liquid chemical is forced out of the space and to an end use station through a discharge conduit, the balloon connected to the pressure vessel only at a pressurized gas inlet.

2. System in accordance with claim 1 wherein said pressure vessel, balloon, and means for delivering pressurized gas are all controlled by a computer.

3. System in accordance with claim 1 wherein all components are housed in a cabinet.

4. System in accordance with claim 1 wherein more than one pressure vessel and balloon combination are present in parallel flow relation to each other, allowing continuous delivery of the liquid chemical to an end use.

5. System in accordance with claim 1 wherein the delivery conduit includes a first sample port.

6. System in accordance with claim 5, further including a first recirculation conduit connecting the delivery conduit and the bulk source.

7. System in accordance with claim 1 further comprising a second sample port on said discharge conduit.

8. System in accordance with claim 7 further comprising a second recirculation conduit connecting the discharge conduit with said bulk source.

9. System in accordance with claim 1 further comprising a manifold connected to said discharge conduit, said manifold having conduits to multiple end use stations.

10. System in accordance with claim 1 including a third recirculation conduit connecting the end use station to said bulk source.

11. Method of transferring and delivering a liquid chemical from a bulk source to an end use station, the method comprising the steps of:

(a) delivering liquid chemical from a bulk source through a delivery conduit using a pump to a pressure vessel, the pressure vessel having an interior surface;

(b) providing a balloon inside the pressure vessel, the balloon having interior and exterior surfaces, the liquid chemical occupying at least a portion of a space between the pressure vessel interior surface and balloon exterior surface the balloon connected to the pressure vessel only at a pressurized gas inlet; and

(c) delivering a gas to the balloon, thereby causing liquid chemical to flow from the space to an end use station through a discharge conduit.

12. Method in accordance with claim 11 including controlling said pressure vessel, said balloon, and said means for delivering pressurized gas by a computer.

13. Method in accordance with claim 11 comprising switching to a second pressure vessel and balloon combination present in parallel flow relation to said pressure vessel, allowing continuous delivery of said liquid chemical to an end use.

14. Method in accordance with claim 11 comprising sampling the liquid chemical flowing through the delivery conduit.

15. Method in accordance with claim 11, comprising recirculating the liquid chemical through a first recirculation conduit connecting the delivery conduit and the bulk source.

16. Method in accordance with claim 11 comprising sampling the liquid chemical flowing through said discharge conduit.

17. Method in accordance with claim 11 comprising recirculating the liquid chemical through a second recirculation conduit connecting the discharge conduit with said bulk source.

18. Method in accordance with claim 11 comprising delivering the liquid chemical through a manifold connected to said discharge conduit, said manifold having conduits to multiple end use stations.

19. Method in accordance with claim 11 comprising recirculating the liquid chemical through a third recirculation conduit connecting the end use station to said bulk source.