Adjusting a fuel on-board a vehicle

Patent metadata

Field	Value
Publication number	US-11293386-B2
Application number	US-201715810407-A
Country	US
Kind code	B2
Filing date	Nov 13, 2017
Priority date	Feb 16, 2016
Publication date	Apr 5, 2022
Grant date	Apr 5, 2022

Abstract

A fuel separation system includes a fuel separator configured to receive a fuel stream and separate the fuel stream, based on a volatility of the fuel stream, into a vapor stream defined by a first auto-ignition characteristic value and a first liquid stream defined by a second auto-ignition characteristic value, the second auto-ignition characteristic value greater than the first auto-ignition characteristic value; and a heat exchanger fluidly coupled between a fuel input of the fuel stream and the fuel separator, the heat exchanger configured to transfer heat from the vapor stream to the fuel stream, and output a heated fuel stream to the fuel separator and a second liquid stream defined by the first auto-ignition characteristic value.

First claim

What is claimed is:

1. A fuel separation system, comprising:
a first stage fuel separator configured to receive a fuel stream and separate the fuel stream, based on a volatility of the fuel stream, into a vapor stream defined by a first auto-ignition characteristic value and a first liquid stream defined by a second auto-ignition characteristic value, the second auto-ignition characteristic value greater than the first auto-ignition characteristic value;
a second stage fuel separator arranged in series with and downstream of the first stage fuel separator and configured to separate the vapor stream into an oxygenate stream and a compound stream, the second stage fuel separator further configured to direct the oxygenate stream to combine with the first liquid stream, and to direct the combined stream to a secondary heat exchanger;
a primary heat exchanger fluidly coupled between a fuel input of the fuel stream and the first stage fuel separator, the primary heat exchanger configured to transfer heat from the vapor stream to the fuel stream, and output a heated fuel stream to the first stage fuel separator and a second liquid stream defined by the first auto-ignition characteristic value;
a variable orifice fluidly coupled directly between the primary heat exchanger and the first stage fuel separator to receive the heated fuel stream and adjust a pressure of the heated fuel stream that enters the first stage fuel separator; and
a controller operatively coupled to control at least one of the first stage fuel separator or the variable orifice to vary a volumetric flow rate of at least one of the heated fuel stream, the vapor stream, or the first liquid stream, and adjust the pressure of the heated fuel stream that enters the first stage fuel separator so that the first auto-ignition characteristic value of the vapor stream meets a desired vapor stream auto-ignition characteristic value, and the second auto-ignition characteristic value of the first liquid stream meets a desired liquid stream auto-ignition characteristic value.

2. The fuel separation system of claim 1 , wherein the primary heat exchanger is configured to condense the vapor stream to the second liquid stream defined by the first auto-ignition characteristic value.

3. The fuel separation system of claim 1 , further comprising a heater coupled between the primary heat exchanger and the first stage fuel separator and configured to receive the heated fuel stream and further heat the heated fuel stream.

4. The fuel separation system of claim 1 , wherein the controller is configured to vary at least one of the first auto-ignition characteristic value or the second auto-ignition characteristic value based, at least in part, on at least one engine operating condition.

5. The fuel separation system of claim 4 , wherein the at least one engine operating condition comprises an engine load, an engine torque, and engine speed, a fuel vapor-liquid ratio, a fuel vapor lock index, a fuel drivability index, a fuel T90 or T95 property, a fuel lubricity, a fuel viscosity, or an engine speed-torque ratio.

6. The fuel separation system of claim 1 , wherein at least one of the first or second stage fuel separators comprises a flash distillation separator.

7. The fuel separation system of claim 1 , wherein the first stage fuel separator comprises a first stage flash distillation fuel separator and the second stage fuel separator comprises a second stage flash distillation fuel separator.

8. The fuel separation system of claim 7 , wherein the first stage flash distillation fuel separator is configured to receive the fuel stream and separate the fuel stream, based on the volatility of the fuel stream, into the vapor stream defined by the first auto-ignition characteristic value and the first liquid stream defined by the second auto-ignition characteristic value, and
the second stage flash distillation fuel separator is configured to separate the vapor stream into the oxygenate stream and the compound stream.

9. The fuel separation system of claim 8 , wherein the second stage flash distillation fuel separator is configured to direct the oxygenate stream to combine with the first liquid stream, and to direct the compound stream to the secondary heat exchanger.

10. The fuel separation system of claim 1 , wherein the first auto-ignition characteristic value comprises a first research octane number (RON) or a first cetane number, and the second auto-ignition characteristic value comprises a second RON or a second cetane number.

11. The fuel separation system of claim 5 , wherein the primary heat exchanger is configured to condense the vapor stream to the second liquid stream defined by the first auto-ignition characteristic value, and the system further comprises a heater coupled between the primary heat exchanger and the first stage fuel separator and configured to receive the heated fuel stream and further heat the heated fuel stream.

12. The fuel separation system of claim 9 , wherein the primary heat exchanger is configured to condense the vapor stream to the second liquid stream defined by the first auto-ignition characteristic value, and the system further comprises a heater coupled between the primary heat exchanger and the first stage fuel separator and configured to receive the heated fuel stream and further heat the heated fuel stream.

13. A method for separating a fuel on-board a vehicle, comprising:
separating, with a first stage fuel separator, a heated fuel stream into a vapor stream and a first liquid stream based on a volatility of the fuel stream, the vapor stream defined by a first auto-ignition characteristic value and the first liquid stream defined by a second auto-ignition characteristic value, the second auto-ignition characteristic value greater than the first auto-ignition characteristic value;
separating, with a second stage fuel separator arranged in series with and downstream of the first stage fuel separator, the vapor stream into an oxygenate stream and a compound stream;
directing the oxygenate stream from the second stage fuel separator to combine with the first liquid stream;
directing the combined stream to a secondary heat exchanger;
supplying an unheated fuel stream and the vapor stream from the first stage fuel separator to a primary heat exchanger;
transferring heat from the vapor stream to the unheated fuel stream to heat the unheated fuel stream;
circulating the heated fuel stream through a variable orifice fluidly coupled directly between the primary heat exchanger and the first stage fuel separator;
controlling the variable orifice to adjust a pressure of the heated fuel stream between the primary heat exchanger and the first stage fuel separator with the variable orifice so that the first auto-ignition characteristic value of the vapor stream meets a desired vapor stream auto-ignition characteristic value, and the second auto-ignition characteristic value of the first liquid stream meets a desired liquid stream auto-ignition characteristic value;
controlling at least one of the first stage fuel separator or the variable orifice to vary a volumetric flow rate of at least one of the heated fuel stream, the vapor stream, or the first liquid stream;
supplying the heated fuel stream to the first stage fuel separator; and
supplying a second liquid stream defined by the first auto-ignition characteristic value from the primary heat exchanger to a fractional fuel tank.

14. The method of claim 13 , further comprising condensing, with the primary heat exchanger, the vapor stream to form the second liquid stream.

15. The method of claim 13 , furthe

Assignees

• Saudi Arabian Oil Co

Inventors

• Hamad Esam Z
• Algunaibet Ibrahim M

Classifications

• F02B61/00

  Adaptations of engines for driving vehicles or for driving propellers; Combinations of engines with gearing (the engine torque being divided by a differential gear for driving a scavenging or charging pump and the engine output shaft F02B39/06; adaptations or combinations of rotary-piston or oscillating-piston engines F02B53/14) · CPC title

• B60K15/00

  Arrangement in connection with fuel supply of combustion engines {or other fuel consuming energy converters, e.g. fuel cells}; Mounting or construction of fuel tanks · CPC title

• F02D19/0671

  Means to generate or modify a fuel, e.g. reformers, electrolytic cells or membranes · CPC title

• F02M37/20

  characterised by means for preventing vapour lock · CPC title

• F02D19/081

  Adjusting the fuel composition or mixing ratio; Transitioning from one fuel to the other · CPC title