WO2017031058A1

WO2017031058A1 - Ashless tbn maintenance of lubricant

Info

Publication number: WO2017031058A1
Application number: PCT/US2016/047036
Authority: WO
Inventors: Howard S. Savage; Roger D. England; Corey W. TROBAUGH; Ryan E. DENTON
Original assignee: Cummins Inc.
Priority date: 2015-08-17
Filing date: 2016-08-15
Publication date: 2017-02-23

Abstract

Described herein is a method for extending lubricant life, comprising treating a lubricant with a lubricant additive which comprises a compound selected from the group consisting of urea, ammonium carbonate, ammonium bicarbonate, and ammonium hydroxide to neutralize acids from oil use and/or contamination by combustion condensates. For example, the lubricant of an internal combustion engine can be treated in situ with an aqueous solution of urea, ammonium carbonate, ammonium bicarbonate, and/or ammonium hydroxide. Also provided is a method for extending lubricant life, comprising use of a urea source on a vehicle that is processed and delivered on board to a lubricant to treat reactive species in the lubricant to increase oil drain interval.

Description

ASHLESS TBN MAINTENANCE OF LUBRICANT

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Application No. 62/205,948 filed August 17, 2015, which is incorporated herein by reference in its entirety.

BACKGROUND

[0002] Current engine oils are not equipped to handle long oil drain intervals in many commercial engines. Metal-based total base number (TBN) boosters have been designed to neutralize the acids generated by the combustion process and to ultimately protect the soft metals from increased corrosion. Metal-based TBN boosters have limitations - with normal oil consumption levels, the ash-based chemicals participate in the combustion process and eventually decrease the usable life of the after-treatment systems. Servicing and replacing after-treatment systems, however, is time intensive and expensive. Because of their negative impact on the after-treatment filters, it is difficult to include a sufficient concentration of these metallic based chemicals for longer corrosion protection and longer oil drain intervals.

[0003] In addition, ammonia gas has been used to control TBN. For example, GB Patent No. 856,764 discloses a method of treatment of used marine diesel engine lubricating oil with ammonia either by injecting ammonia gas into the oil or by spraying the oil into an atmosphere of ammonia gas or by washing the oil with aqueous ammonia. However, this method does not solve the problem of extending the lubricant life in a working engine as it concerns the lube oil already spent.

[0004] PCT Publication No. WO 2010/018389 discloses a method of extending the lubricant life in an internal combustion engine, which comprises feeding ammonia gas to the crankcase without it passing through an engine cylinder. The crankcase gases are sampled and measured automatically for acidic species and the flow of ammonia gas into the crankcase is regulated automatically. PCT Publication No. WO 2010/018389 also discloses feeding the ammonia gas into the engine intake. However, ammonia gas is hazardous to the environment.

SUMMARY

[0005] Disclosed here is a method for controlling TBN of engine lubricant that does not rely on ash forming compounds or environmentally hazardous gases. A first set of embodiments described herein relates to a method for extending lubricant life, comprising treating a lubricant with a lubricant additive which comprises an acid neutralizing compound (e.g., ammonium carbonate, ammonium bicarbonate, and ammonium hydroxide) or a precursor to ammonia (e.g., urea, ammonium carbonate, and ammonium bicarbonate), to neutralize acids from oil use and/or contamination by combustion condensates. In some embodiments, the lubricant of an internal combustion engine is treated in situ with an aqueous solution of urea, ammonium carbonate, ammonium bicarbonate, and/or ammonium hydroxide.

[0006] In one embodiment, the lubricant is treated in a diesel engine in situ with the lubricant additive.

[0007] In one embodiment, the lubricant is treated in a natural gas engine in situ with the lubricant additive.

[0008] In one embodiment, the lubricant additive comprises urea. In one embodiment, the lubricant additive comprises an aqueous solution of urea. In one embodiment, a concentration of urea in the aqueous solution is about 30 to 35%.

[0009] In one embodiment, the lubricant is treated in an internal combustion engine in situ with the lubricant additive, and wherein the lubricant additive produces ammonia by thermal decomposition of urea upon contacting hot lubricant. [0010] In one embodiment, the lubricant additive comprises ammonium carbonate. In one embodiment, the lubricant additive comprises an aqueous solution of ammonium carbonate.

[0011] In one embodiment, the lubricant additive comprises ammonium bicarbonate. In one embodiment, the lubricant additive comprises an aqueous solution of ammonium bicarbonate.

[0012] In one embodiment, the lubricant additive comprises ammonium hydroxide. In one embodiment, the lubricant additive comprises an aqueous solution of ammonium hydroxide.

[0013] In one embodiment, the lubricant additive is in liquid form and is substantially free of ammonia gas.

[0014] In one embodiment, the lubricant additive is substantially free of metal- based TBN boosters.

[0015] In one embodiment, the lubricant additive is an ashless additive substantially free of ash forming compounds.

[0016] In one embodiment, the lubricant is derived from synthetic oil, mineral oil, or a mixture thereof.

[0017] In one embodiment, the lubricant is a used engine lubricant. In one embodiment, the lubricant is a new engine lubricant.

[0018] In one embodiment, the treatment with the lubricant additive extends lubricant life by at least about 10%.

[0019] In one embodiment, the lubricant additive increases the TBN of the lubricant by at least about 1 mg KOH/g.

[0020] In one embodiment, an ion exchange or adsorption device is used for treating the lubricant. [0021] In one embodiment, the ion exchange or adsorption device is

periodically regenerated by contacting the lubricant additive.

[0022] Another set of embodiments described herein relates to an ashless oil system and a means for maintaining TBN, which would enable longer oil change intervals without risk to the engine system being lubricated and/or damage to the after- treatment system.

[0023] Still another set of embodiments described herein relates to treatment of lubricant with ammonia derived from urea, ammonium carbonate, ammonium

bicarbonate, and/or other compounds to neutralize acids from oil use and/or

contamination by combustion condensates. Ammonia in water as ammonium hydroxide provides base without ash associated with other caustics. Controlled additions of ammonia/ammonium hydroxide to the oil would neutralize acids and maintain TBN without adding ash forming compounds to the oil.

[0024] Still another set of embodiments described herein relates to use of a urea source on a vehicle that is processed and delivered on board to a lubricant to treat reactive species in the lubricant to increase oil drain interval.

[0025] In one embodiment, an ion exchange or adsorption device is used for treating the lubricant.

[0026] In one embodiment, the ion exchange or adsorption device is

periodically regenerated by contacting a lubricant additive comprising a compound selected from the group consisting of urea, ammonium carbonate, ammonium

bicarbonate, and ammonium hydroxide.

[0027] In one embodiment, the urea source is a diesel exhaust fluid for reducing nitrogen oxide from an exhaust stream.

[0028] In one embodiment, the method comprises contacting the diesel exhaust fluid with hot exhaust gas stream to produce ammonia by thermal decomposition of urea. [0029] In one embodiment, the method comprises processing and delivering the ammonia obtained on board to the lubricant.

[0030] These and other features, together with the organization and manner of operation thereof, will become apparent from the following detailed description and also the accompanying claims and abstract.

DETAILED DESCRIPTION

[0031] Embodiments described herein relates to a method for extending lubricant life, comprising treating a lubricant with a lubricant additive which comprises an acid neutralizing compound (e.g., ammonium carbonate, ammonium bicarbonate, and ammonium hydroxide) or a precursor to ammonia (e.g., urea, ammonium carbonate, and ammonium bicarbonate), to neutralize acids from oil use and/or contamination by combustion condensates.

[0032] The method can comprise, for example, treating the lubricant in an engine in situ with the lubricant additive. The method can comprise, for example, treating the lubricant in an internal combustion engine in situ with the lubricant additive. In certain implementations, the method comprises treating the lubricant in a diesel engine in situ with the lubricant additive. In other implementations, the method comprises treating the lubricant in a natural gas engine in situ with the lubricant additive.

[0033] The lubricant additive can comprise, for example, urea. In certain implementations, the lubricant additive comprises an aqueous solution of urea. The concentration of urea in the aqueous solution can be, for example, about 10% to about 50%), about 20%) to about 40%, or about 30%> to about 35%. In some embodiments, upon contacting of the lubricant additive with the hot lubricant in the engine, the lubricant additive produces ammonia in situ by thermal decomposition of urea.

[0034] The lubricant additive can comprise, for example, ammonium carbonate. In certain implementations, the lubricant additive comprises an aqueous solution of ammonium carbonate. The concentration of ammonium carbonate in the aqueous solution can be, for example, about 10% to about 50 %, about 20% to about 40%, or about 30%) to about 35%. In some embodiments, upon contacting of the lubricant additive with the hot lubricant in the engine, the lubricant additive produces ammonia in situ by thermal decomposition of ammonium carbonate.

[0035] The lubricant additive can comprise, for example, ammonium

bicarbonate. In certain implementations, the lubricant additive comprises an aqueous solution of ammonium bicarbonate. The concentration of ammonium bicarbonate in the aqueous solution can be, for example, about 10% to about 50 %, about 20% to about 40%), or about 30% to about 35%. In some embodiments, upon contacting of the lubricant additive with the hot lubricant in the engine, the lubricant additive produces ammonia in situ by thermal decomposition of ammonium bicarbonate.

[0036] The lubricant additive can comprise, for example, ammonium

hydroxide. In certain implementations, the lubricant additive comprises an aqueous solution of ammonium hydroxide. The concentration of ammonium hydroxide in the aqueous solution can be, for example, about 10% to about 50%, about 20% to about 40%, or about 30% to about 35%.

[0037] In addition to the acid neutralizing compound or the precursor to ammonia, the lubricant additive can further comprise other ashless additives to provide lubrication, corrosion inhibition, or other functional needs.

[0038] The lubricant additive described herein can be, for example, in liquid form and is substantially free of ammonia gas. In certain implementations, the lubricant additive described herein is substantially free of liquid ammonia. In some embodiments, the lubricant additive described herein is substantially free of ammonium phosphate.

[0039] The lubricant additive described herein can be, for example,

substantially free of metal-based TBN boosters. In certain implementations, the lubricant additive described herein is an ashless additive substantially free of ash forming compounds. In some embodiments, the lubricant additive described herein is substantially free of metal species.

[0040] In certain implementations, the method described herein does not comprise the injection of ammonia gas into a crankcase of an engine. In some embodiments, the method described herein does not comprise the injection of ammonia gas into an engine intake.

[0041] The amount of the lubricant additive to be added to the engine lubricant can be, for example, controlled to be proportional to the propensity of the engine operating condition to produce acidic blow-by gases or to thermally degrade the oil. In some embodiments, duty cycle parameters can be used for high thermal degradation to control additive delivery.

[0042] The amount of the lubricant additive to be added to the engine lubricant can be, for example, controlled to be proportional to the pH of the lubricant.

[0043] The amount of the lubricant additive to be added to the engine lubricant can be, for example, controlled to be proportional to the temperature of the lubricant.

[0044] The amount of the lubricant additive to be added to the engine lubricant can be, for example, controlled to be proportional to the separable aqueous fluid content of the lubricant.

[0045] The amount of the lubricant additive to be added to the engine lubricant can be, for example, controlled to be proportional to the electrical conductivity of the lubricant.

[0046] In some embodiments, the lubricant is derived from synthetic oil. In certain implementations, the lubricant is derived from mineral oil. The lubricant can also be, for example, derived from a mixture of synthetic oil and mineral oil.

[0047] In some embodiments, the lubricant is a used engine lubricant, i.e., the lubricant has been run through an engine system undergoing an internal combustion process. The lubricant can be, for example, a used engine lubricant in need of boosting TBN. In certain other implementations, the lubricant is a new engine lubricant.

[0048] The treatment with the lubricant additive described herein can increase the initial TBN of a used engine lubricant by, for example, at least about 1 mg KOH/g, at least about 2 mg KOH/g, at least about 3 mg KOH/g, or at least about 4 mg KOH/g.

[0049] The treatment with the lubricant additive described herein can increase the initial TBN of a new engine lubricant by, for example, at least about 1 mg KOH/g, at least about 2 mg KOH/g, at least about 3 mg KOH/g, or at least about 4 mg KOH/g.

[0050] The treatment with the lubricant additive can extend life of a used engine lubricant by, for example, at least about 10%, at least about 20%, at least about 50%, or at least about 100%.

[0051] The treatment with the lubricant additive described herein can extend life of a new engine lubricant by, for example, at least about 10%>, at least about 20%, at least about 50%), or at least about 100%>.

[0052] The treatment with the lubricant additive described herein can increase standard oil drain intervals for an internal combustion engine by, for example, at least about 10%), at least about 20%, at least about 50%, or at least about 100%, compared to the treatment with a conventional oil additive based on one or more metallic TBN boosters. In certain implementations, the treatment with the lubricant additive described herein can increase standard oil drain intervals for a diesel or natural gas engine by, for example, at least about 10%, at least about 20%, at least about 50%, or at least about 100%), compared to the treatment with a conventional oil additive based on one or more metallic TBN boosters.

[0053] In some embodiments, an ion exchange or adsorption device is used for treating the lubricant. The ion exchange or adsorption device can be periodically regenerated by contacting the lubricant additive described herein. [0054] Additional embodiments described herein relates to use of a urea source on a vehicle that is processed and delivered on board to a lubricant to treat reactive species in the lubricant to increase oil drain interval. The urea source can be, for example, a diesel exhaust fluid which is typically used for reducing nitrogen oxide from an exhaust stream. Upon contacting of the diesel exhaust fluid with hot exhaust gas stream, ammonia can be produced by the thermal decomposition of urea. The ammonia obtained can be processed and delivered on board to a lubricant to treat reactive species in the lubricant to increase oil drain interval.

[0055] As used herein, the singular terms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a compound can include multiple compounds unless the context clearly dictates otherwise.

[0056] As used herein, the terms "substantially," "substantial," and "about" are used to describe and account for small variations. When used in conjunction with an event or circumstance, the terms can refer to instances in which the event or circumstance occurs precisely as well as instances in which the event or circumstance occurs to a close approximation. For example, the terms can refer to less than or equal to ±10%, such as less than or equal to ±5%, less than or equal to ±4%, less than or equal to ±3%, less than or equal to ±2%, less than or equal to ±1%, less than or equal to ±0.5%, less than or equal to ±0.1%), or less than or equal to ±0.05%.

[0057] Additionally, amounts, ratios, and other numerical values are sometimes presented herein in a range format. It is to be understood that such range format is used for convenience and brevity and should be understood flexibly to include numerical values explicitly specified as limits of a range, but also to include all individual numerical values or sub-ranges encompassed within that range as if each numerical value and subrange is explicitly specified. For example, a ratio in the range of about 1 to about 200 should be understood to include the explicitly recited limits of about 1 and about 200, but also to include individual ratios such as about 2, about 3, and about 4, and sub-ranges such as about 10 to about 50, about 20 to about 100, and so forth. [0058] In the foregoing description, it will be readily apparent to one skilled in the art that varying substitutions and modifications may be made to the invention disclosed herein without departing from the scope and spirit of the invention. The invention illustratively described herein suitably may be practiced in the absence of any element or elements, limitation or limitations, which is not specifically disclosed herein. The terms and expressions which have been employed are used as terms of description and not of limitation, and there is no intention that in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention. Thus, it should be understood that although the present invention has been illustrated by specific embodiments and optional features, modification and/or variation of the concepts herein disclosed may be resorted to by those skilled in the art, and that such modifications and variations are considered to be within the scopes of this invention

Claims

CLAIMS What is claimed is:

1. A method for extending lubricant life, comprising treating a lubricant with a lubricant additive comprising a compound or mixture comprising one or more of urea, ammonium carbonate, ammonium bicarbonate, or ammonium hydroxide to neutralize acids from oil use and/or contamination by combustion condensates.

2. The method of claim 1, wherein the lubricant is treated in an internal combustion engine in situ with the lubricant additive.

3. The method of claim 1, wherein the lubricant is treated in a diesel engine in situ with the lubricant additive.

4. The method of claim 1, wherein the lubricant is treated in a natural gas engine in situ with the lubricant additive.

5. The method of claim 1, wherein the lubricant additive comprises urea.

6. The method of claim 1, wherein the lubricant additive comprises an aqueous solution of urea.

7. The method of claim 6, wherein a concentration of urea in the aqueous solution is about 30 to 35%.

8. The method of claim 6, wherein the lubricant is treated in an internal combustion engine in situ with the lubricant additive, and wherein the lubricant additive produces ammonia by thermal decomposition of urea upon contacting hot lubricant.

9. The method of claim 1, wherein the lubricant additive comprises ammonium

carbonate.

10. The method of claim 1, wherein the lubricant additive comprises an aqueous solution of ammonium carbonate.

11. The method of claim 1, wherein the lubricant additive comprises ammonium bicarbonate.

12. The method of claim 1, wherein the lubricant additive comprises an aqueous solution of ammonium bicarbonate.

13. The method of claim 1, wherein the lubricant additive comprises ammonium

hydroxide.

14. The method of claim 1, wherein the lubricant additive comprises an aqueous solution of ammonium hydroxide.

15. The method of claim 1, wherein the lubricant additive is in liquid form and is

substantially free of ammonia gas.

16. The method of claim 1, wherein the lubricant additive is substantially free of metal- based TBN boosters.

17. The method of claim 1, wherein the lubricant additive is an ashless additive

substantially free of ash forming compounds.

18. The method of claim 1, wherein the lubricant is derived from synthetic oil, mineral oil, or a mixture thereof.

19. The method of claim 1, wherein the lubricant is a used engine lubricant.

20. The method of claim 1, wherein the lubricant is a new engine lubricant.

21. The method of claim 1, wherein the treatment with the lubricant additive extends lubricant life by at least about 10%.

22. The method of claim 1, wherein the lubricant additive increases the total base number (TBN) of the lubricant by at least about 1 mg KOH/g.

23. The method of claim 1, wherein an ion exchange or adsorption device is used for treating the lubricant.

24. The method of claim 23, wherein the ion exchange or adsorption device is

periodically regenerated by contacting the lubricant additive.

25. A method for extending lubricant life, comprising use of a urea source on a vehicle that is processed and delivered on board to a lubricant to treat reactive species in the lubricant to increase oil drain interval.

26. The method of claim 25, wherein an ion exchange or adsorption device is used for treating the lubricant.

27. The method of claim 26, wherein the ion exchange or adsorption device is

periodically regenerated by contacting a lubricant additive comprising a compound or mixture comprising one or more of urea, ammonium carbonate, ammonium bicarbonate, or ammonium hydroxide.

28. The method of claim 25, wherein the urea source is a diesel exhaust fluid for reducing nitrogen oxide from an exhaust stream.

29. The method of claim 28, further comprising contacting the diesel exhaust fluid with hot exhaust gas stream to produce ammonia by thermal decomposition of urea.

30. The method of claim 29, further comprising processing and delivering the ammonia obtained on board to the lubricant.