Process and apparatus for making aqueous hydrocarbon fuel compositions, and ...

1

PROCESS AND APPARATUS FOR MAKING
AQUEOUS HYDROCARBON FUEL
COMPOSITIONS, AND AQUEOUS
HYDROCARBON FUEL COMPOSITION

5

TECHNICAL FIELD

This invention relates to a process and apparatus for making aqueous hydrocarbon fuel compositions. The invention also relates to stable aqueous hydrocarbon fuel compositions. The process and apparatus are suitable for dispensing the fuels to end users in wide distribution networks.

BACKGROUND OF THE INVENTION

Internal combustion engines, especially diesel engines, 15 using water mixed with fuel in the combustion chamber can produce lower NO^,, hydrocarbon and particulate emissions per unit of power output. However, a problem with adding water relates to the fact that emulsions form in the fuel and these emulsions tend to be unstable. This has reduced the 20 utility of these fuels in the marketplace. It would be advantageous to enhance the stability of these fuels sufficiently to make them useful in the marketplace. Another problem relates to the fact that due to the instability associated with these fuels, it is difficult to make them available to end users 25 in a wide distribution network. The fuels tend to break down before they reach the end user. It would be advantageous to provide a process and apparatus that could be used for blending these fuels at the dispensing site for the end user and therefore make the fuels available to end users in wide 30 distribution networks.

SUMMARY OF THE INVENTION

This invention provides for a process for making an 3J aqueous hydrocarbon fuel composition, comprising: (A) mixing a normally liquid hydrocarbon fuel and at least one chemical additive to form a hydrocarbon fuel-additive mixture; and

(B) mixing said hydrocarbon fuel-additive mixture with 40 water under high shear mixing conditions in a high shear mixer to form said aqueous hydrocarbon fuel composition, said aqueous hydrocarbon fuel composition including a discontinuous aqueous phase, said discontinuous aqueous phase being comprised of aqueous droplets having a mean 45 diameter of 1.0 micron or less. A critical feature of this invention relates to the fact that the aqueous phase droplets have a mean diameter of 1.0 micron or less. This feature is directly related to the enhanced stability characteristics of the inventive aqueous hydrocarbon fuel compositions. 50

This invention further provides for an apparatus for making an aqueous hydrocarbon fuel composition, comprising: a high shear mixer; a blend tank; a chemical additive storage tank and a pump and conduit for transferring a chemical additive from said chemical additive storage tank 55 to said blend tank; a conduit for transferring a hydrocarbon fuel from a hydrocarbon fuel source to said blend tank; a conduit for transferring a hydrocarbon fuel-additive mixture from said blend tank to said high shear mixer; a water conduit for transferring water from a water source to said 60 high shear mixer; a fuel storage tank; a conduit for transferring an aqueous hydrocarbon fuel composition from said high shear mixer to said fuel storage tank; a conduit for dispensing said aqueous hydrocarbon fuel composition from said fuel storage tank; a programmable logic controller for 65 controlling: (i) the transfer of said chemical additive from said chemical additive storage tank to said blend tank; (ii)

2

the transfer of said hydrocarbon fuel from said hydrocarbon fuel source to said blend tank; (iii) the transfer of said hydrocarbon fuel-additive mixture from said blend tank to said high shear mixer; (iv) the transfer of water from said water source to said high shear mixer; (v) the mixing of said hydrocarbon fuel-additive mixture and said water in said high shear mixer; and (vi) the transfer of said aqueous hydrocarbon fuel composition from said high shear mixer to said fuel storage tank; and a computer for controlling said programmable logic controller.

In one embodiment, the inventive apparatus is in the form of a containerized equipment package or unit that operates automatically. This unit can be programmed and monitored locally at the site of its installation, or it can be programmed and monitored from a location remote from the site of its installation. The fuel is dispensed to end users at the installation site. This provides a way to make the aqueous hydrocarbon fuels compositions prepared in accordance with the invention available to end users in wide distribution networks.

This invention also relates to an aqueous hydrocarbon fuel composition comprising: a continuous phase of a normally liquid hydrocarbon fuel; a discontinuous aqueous phase, said discontinuous aqueous phase being comprised of aqueous droplets having a mean diameter of 1.0 micron or less; and an emulsifying amount of an emulsifier composition comprising (i) a hydrocarbon fuel-soluble product made by reacting a hydrocarbyl substituted carboxylic acid acylating with ammonia or an amine, the hydrocarbyl substituent of said acylating agent having about 50 to about 500 carbon atoms, (ii) an ionic or a nonionic compound having a hydrophilic lipophilic balance (HLB) of about 1 to about 10, or a mixture of (i) and (ii), in combination with (iii) a water-soluble salt distinct from (i) and (ii).

BRIEF DESCRIPTION OF THE DRAWINGS

In the annexed drawings, like parts and features have like designations.

FIG. 1 is a flow sheet illustrating one embodiment of the inventive process and apparatus.

FIG. 2 is an overhead plan view illustrating one embodiment of the inventive apparatus which is in the form of a containerized equipment package or unit.

FIG. 3 is a flow sheet illustrating the electronic communication between a plurality of programmable logic controllers associated with corresponding apparatus for operating the inventive process, the programmable logic controllers being located remotely from a programming computer communicating with such programmable logic controllers and a monitoring computer communicating with such programmable logic controllers.

FIG. 4A is a partial cut away view of one embodiment of the high shear mixer provided for in accordance with the invention, this high shear mixer being a rotor-stator mixer having three rotor-stators arranged in series.

FIG. 4B is an enlarged plan view showing the interior of one of the rotors and one of the stators illustrated in FIG. 4A.

FIG. 5 is a plot of the number of aqueous phase droplets verses droplet diameter determined for the aqueous hydrocarbon fuel composition (formulation A) produced in the Example.

DETAILED DESCRIPTION OF THE
PREFERRED EMBODIMENTS

As used herein, the terms "hydrocarbyl substituent," "hydrocarbyl group," "hydrocarbyl substituted," "hydrocar3

bon group," and the like, are used to refer to a group having one or more carbon atoms directly attached to the remainder of a molecule and having a hydrocarbon or predominantly hydrocarbon character. Examples include:

(1) purely hydrocarbon groups, that is, aliphatic (e.g., 5 alkyl, alkenyl or alkylene), and alicyclic (e.g., cycloalkyl, cycloalkenyl) groups, aromatic groups, and aromatic-, aliphatic-, and alicyclic-substituted aromatic groups, as well as cyclic groups wherein the ring is completed through another portion of the molecule 1° (e.g., two substituents together forming an alicyclic group);

(2) substituted hydrocarbon groups, that is, hydrocarbon groups containing non-hydrocarbon groups which, in the context of this invention, do not alter the predomi- 15 nantly hydrocarbon nature of the group (e.g., halo, hydroxy, alkoxy, mercapto, alkylmercapto, nitro, nitroso, and sulfoxy);

(3) hetero substituted hydrocarbon groups, that is, hydrocarbon groups containing substituents which, while 20 having a predominantly hydrocarbon character, in the context of this invention, contain other than carbon in

a ring or chain otherwise composed of carbon atoms. Heteratoms include sulfur, oxygen, nitrogen. In general, no more than two, and in one embodiment no more than one, non-hydrocarbon substituent is present for every ten carbon atoms in the hydrocarbon group. The term "lower" when used in conjunction with terms such as alkyl, alkenyl, and alkoxy, is intended to describe such groups that contain a total of up to 7 carbon atoms.

The term "water-soluble" refers to materials that are soluble in water to the extent of at least one gram per 100 milliliters of water at 25° C.

The term "fuel-soluble" refers to materials that are soluble

35

in a normally liquid hydrocarbon fuel (e.g. gasoline or diesel fuel) to the extent of at least one gram per 100 milliliters of fuels at 25° C.

The Process and Apparatus

40

The inventive process may be conducted on a batch basis or on a continuous basis. The process and apparatus described below relates to a batch process. Referring initially to FIG. 1, the apparatus includes high shear mixer 10, blend tank 12, hydrocarbon fuel inlet 14, chemical additive 4J storage tank 16, water storage tank 18, antifreeze agent storage tank 20, aqueous hydrocarbon fuel storage tank 22, and fuel dispenser 24.

Hydrocarbon fuel enters through hydrocarbon fuel inlet 14 and flows to blend tank 12 through conduit 30. Arranged 50 in series along conduit 30 between inlet 14 and blend tank 12 are isolation valve 32, pressure gauge 34, strainer 36, pump 38, solenoid valve 40, flow meter and totalizer 42, calibration outlet is valve 44, check valve 46 and isolation valve 48. 55

Conduit 50 extends from chemical additive storage tank 16 to blend tank 12 and is adapted for transferring the chemical additive from chemical additive storage tank 16 to blend tank 12. Arranged in series along conduit 50 are isolation valve 52, quick disconnect 54, isolation valve 56, 60 strainer 58,. pump 60, solenoid valve 62, flow meter and totalizer 64, calibration outlet valve 66, check valve 68 and isolation valve 69.

Conduit 70 extends from water storage tank 18 to connecting tee 71 where it connects with conduit 90. Arranged 65 in series along conduit .70 between water storage tank 18 and connecting tee 71 are valves 72 and 73, strainer 74,

4

pump 76, solenoid valve 78, flow meter and totalizer 80, calibration outlet valve 81, check valve 82, and isolation valve 83. Conduit 84 extends from water inlet 85 to water deionizer 86. Conduit 87 extends from water deionizer 86 to water storage tank 18.

Conduit 90 extends from antifreeze storage tank 20 to connecting tee 71.

Arranged in series along conduit 90 between antifreeze agent storage tank 20 and connecting tee 71 are valves 92 and 94, strainer 96, pump 98, solenoid valve 100, flow meter and totalizer 102, check valve 104 and isolation valve 106.

Conduit 108 extends from connecting tee 71 to connecting tee 110. Conduit 116 extends from blend tank 12 to connecting tee 110. Actuated valve 118 is positioned between blend tank 12 and connecting tee 110 in conduit 116. Conduit 112 extends from connecting tee 110 to the inlet to high shear mixer 10. Check valve 114 is located in conduit 112 between connecting tee 110 and the inlet to high shear mixer 10.

Conduit 120 extends from the outlet to high shear mixer 10 to aqueous hydrocarbon fuel storage tank 22. Arranged in series along conduit 120 are throttling valve 122, connecting tee 124 and actuated valve 126. Conduit 130 extends from connector tee 124 to blend tank 12. Actuated valve 132 is positioned in conduit 130 between connecting tee 124 and blend tank 12. Conduit 130 is provided for recycling the mixture of hydrocarbon fuel-additive mixture and water (and optionally antifreeze agent) back through blend tank 12 and then again through high shear mixer 10.

Conduit 135 extends from aqueous hydrocarbon fuel storage tank 22 to connecting tee 110 and is provided for recycling aqueous hydrocarbon fuel composition from tank 22 back through high shear mixer 10 when it is desired to subject the aqueous hydrocarbon fuel composition to additional high shear mixing. Arranged in series along conduit 135 are isolation valve-136, actuated valve 137 and calibration outlet valve 138. This recycling can be done to avoid undesired settling in tank 22 after the aqueous hydrocarbon fuel composition has been blended.

Conduit 140 extends from aqueous hydrocarbon fuel storage tank 22 to fuel dispenser 24. Dispensing pump 142 is connected to conduit 140 and is positioned between aqueous hydrocarbon fuel storage tank 22 and fuel dispenser 24. Dispensing pump 142 is adapted for pumping the aqueous hydrocarbon fuel composition from aqueous hydrocarbon fuel storage tank 22 to fuel dispenser 24. Users of the aqueous hydrocarbon fuel composition may obtain the fuel from dispenser 24.

A programmable logic controller (PLC), not shown in FIG. 1, is provided for controlling: (i) the transfer of chemical additive from the chemical additive storage tank 16 to blend tank 12; (ii) the transfer of hydrocarbon fuel from hydrocarbon fuel inlet 14 to the blend tank 12; (iii) the transfer of hydrocarbon fuel-additive mixture from the blend tank 12 to high shear mixer 10; (iv) the transfer of water from the water storage tank 18 to high shear mixer 10; (v) the mixing in high shear mixer 10 of the hydrocarbon fuel-additive mixture and the water; and (vi) the transfer of the aqueous hydrocarbon fuel composition from the high shear mixer 10 to the aqueous hydrocarbon fuel storage tank 22. When an antifreeze agent is used, the PLC controls the transfer of the antifreeze agent from the antifreeze agent storage tank 20 to connecting tee 71 where it is mixed with water from conduit 70. When it is desired to recycle the aqueous hydrocarbon fuel composition through mixer 10 for additional high shear mixing, the PLC also controls such