Method and kit for treatment of components utilized in a crude oil service operation

Abstract

A method and kit for treatment of a stainless steel or other nickel alloy component utilized in a crude oil service operation including cleaning a surface of the component to remove surface contamination; drying the cleaned surface of the component; applying a coat of Self-Assembled Monolayer of Phosphonate (SAMP) to the cleaned and dried surface of the component to form a treated component; and installing the treated component into a section of a crude oil service operation. The coating reduces paraffin/asphaltene deposition on the component. The kit includes a cleaner wipe impregnated with a cleaning substance for cleaning the component; a nano-coating wipe impregnated with a SAMP for applying a nano-coating of the SAMP to the component; and instructions for treating said component utilizing the cleaner wipe and the nano-coating wipe.

Claims

1. A method for treating cooperating surfaces of an elongated stainless steel tube and a float carrier of a digital level sensor utilized in a crude oil service operation comprising the steps of: cleaning select surfaces of said tube and float carrier to remove surface contamination; drying said cleaned surfaces of said tube and float carrier; applying a coat of a Self-Assembled Monolayer of Phosphonate (SAMP) composition within a glycol based carrier to said cleaned and dried surfaces of said tube and float carrier to form treated components; and installing said treated components into a section of a crude oil service operation, said coating reducing paraffin/asphaltene deposition on said treated components.

2. The method of claim 1 wherein said applying step further comprises utilizing a nano-coating wipe impregnated with said SAMP composition.

3. The method of claim 2 wherein said cleaning step further comprises utilizing a cleaner/wipe impregnated with a cleaning substance.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) FIG. 1 illustrates a diagram of the present invention method showing the process steps.

(2) FIG. 2 is the perspective view of a foil packet of the present inventive kit.

(3) FIG. 3 is a basic illustration of some components of a digital level sensor described in this application.

(4) FIGS. 4A-4F are illustrations of capacitance sensors which have been treated along exposed surfaces with the anti-paraffin coating composition of the present invention.

(5) FIGS. 4A-4C illustrate capacitance sensors having cylindrical outer housings.

(6) FIGS. 4D-4E show an alternative embodiment of a capacitance sensor having a generally rectangular outer housing.

(7) FIG. 4F is a perspective view of the embodiment of FIGS. 4D and 4E.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(8) The present invention, to reduce paraffin/asphaltene deposition on stainless steel and nickel alloy components, utilizes a composition known as a Self-Assembled Monolayer of Phosphonate (SAMP). SAMP is commercially available from a wide range of suppliers. One such supplier is Aculon, Inc., San Diego, Calif. who assisted in the development of the present invention. Typically, SAMP is utilized with an alcohol-based carrier which allows for rapid drying. It is anticipated that the SAMP may be combined with a glycol carrier for use in the treatment of components used in crude oil service operation.

(9) A monolayer is a nanoscale coating that is one molecule thick or 1-4 nanometers in thickness (1 nm=1.times.10-9 meters). A phosphonate is a phosphorous acid connected with a carbon-based group through a highly stable phosphorus carbon bond.

(10) The phosphonic acid reacts with the component surface through stable metal phosphorus bonds, and the carbons are chosen for their non-stick chemical functionality. The SAMP is covalently bound to the substrate, forming a durable, low-surface tension, non-stick surface. This permanent chemical bond is highly stable under ambient conditions. Currently, an alcohol-based carrier is combined with the SAMP in some applications, but using a glycol-based carrier is unique in the crude oil environments of the invention.

(11) Through standard Dyne pen testing, surface energy is shown to be significantly and permanently reduced through application of a nano-coating to the tested component. Field trials with components treated via the present inventive process indicate a significant reduction of paraffin/asphaltene deposition on stainless steel sensor components installed in crude oil storage tanks operated in low acidity/low turbulence applications at normal temperatures.

(12) The present inventive process may be utilized in the manufacture of sensors and instrumentation for a crude oil service operation. The method is simple: clean, dry, apply, insert, and monitor process, as illustrated in FIG. 1.

(13) As an example, the manufacture of a vertical crude oil storage tank level sensor includes a continuous 316L, square, stainless steel outer tubing that cooperates with the float carrier and all electronic sensor components and switches that are activated by the movement of float carrier to measure the level of the liquid in the storage tank. FIG. 3 shows the square tubing 50 of a digital level sensor (DLS), a float carrier 52 with floats members 54 attached to the carrier 52. During operation, the outer surface 56 of tubing comes into contact with the inner surface 58 of the carrier 52. This sliding contact between the tubing 50 and the inner surface 58 of the float carrier 52 is adversely affected if paraffin or asphaltene deposits build up on these surfaces. When deposits build up on the surfaces of the components, the float carrier 52 does not freely move up and down the tubing 50, thereby causing false level readings in the digital level sensor. The outer tubing extends the entire length of the sensor from top tank connection to the bottom of the sensor. After assembly and testing, the sensor is disassembled and the nano-treatment is completed in the following steps:

(14) a. The sensor assembly including the stainless steel tubes 50, float carrier 52, and floats 54 are placed on horizontal support racks. The entire sensor assembly is thoroughly cleaned on all sides with an alcohol or phosphate-based detergent laden sponge or wipe 60 to remove any mill oil, dirt, grease, etc. and liberally flushed with clean water. This process step is repeated until all visual indications of surface contaminants are removed.

(15) b. The assembly is thoroughly dried using clean, lint-free cloth or absorbent paper towels.

(16) c. Immediately after drying, the nano-treatment chemical composition of the present invention (SAMP) is directly applied to the clean outer tube surfaces 56 and the inner carrier surfaces 58 of the assembly parts with a soft cloth or wipe 62 impregnated with the SAMP composition and gently rubbed into the outer surface 56 and inner surface 58 in order to assure complete chemical coverage. After approximately 1 minute of contact time, excess SAMP composition residue is removed and the complete assembly is thoroughly dried and reassembled.

(17) According to the present inventive method, capacitance sensors 70A, 70B, 70C and 70D as shown in FIGS. 4A-4F may be treated as described above. The nano-treatment chemical composition (SAMP) is directly applied to the clean outer surfaces 72A, 72B, 72C, 72D; the inner surfaces 74A-74D; and core elements 78A-78D as described above. It may be further understood that openings 76A, 76B, and 76C in FIGS. 4A-4C allow crude oil to flow through the sensors, 70A-70C and become exposed to the sensor core 78A-78C. In FIGS. 4D-4F, capacitance sensor 70D has a different, unique design wherein rather from utilizing a generally, cylindrical tube 80A-80C, as shown in FIGS. 4A-4C, two spaced-apart stainless steel plates 90 are held in a generally parallel relationship by two, perforated plastic sidewalls 92. A shrink wrapped printed circuit board sensor 94, with an explosion-proof head 91 attached to one end of the sensor, is disposed within the generally rectangular enclosure or housing formed by the two steel plates 90 and the perforated plastic side walls 92.

(18) The nano-treatment chemical composition (SAMP) is applied to the inner surfaces 96 and outer surfaces 98 of the spaced-apart stainless steel plates 90. Crude oil flows through the perforation 93 in the sidewall 92 to be read by the sensor printed circuit board 94.

(19) Excess SAMP composition residue is removed from the treated surfaces. With the sensors 70A, 70B, 70C and 70D, it is the utilization of the anti-paraffin composition along the surfaces exposed to the crude oil which reduces the paraffin build-up which may affect the sensitivity of the sensor.

(20) In future applications involving larger scale factory coating processes, the manual system described above will utilize more automated processes, including spray-type applicators and/or a tank dip system.

(21) In another embodiment, a kit may be employed wherein individual wipes 60 and 62 (FIG. 2) are separately sealed and robustly packaged to withstand long-term storage and handling. Wipe 60 is a cleaning wipe having an alcohol or phosphate-based detergent. Wipe 62 is impregnated with a SAMP composition appropriate for the application. The chemical components are non-toxic, REACH compliant (having approximately the same environmental characteristics as common isopropyl alcohol), and have no known adverse environmental impacts. No specialized training or Personal Protective Equipment (PPE) is required for use.

(22) A proper application of the nano-coating composition produces a permanent molecular bond that is highly stable under normal ambient conditions. However, components subjected to turbulent flow profiles in which basic sediment index is high (abrasive service), or those subject to high acidity/temperature may require a re-application of the protective coating due to surface abrasion of the metal component.

(23) It should be understood that the AP coating is monitored to evaluate the effectiveness of the SAMP composition coating. Recoating of components may be accomplished by cleaning, drying, and applying, as described above.

(24) It should be understood that the SAMP composition of the present invention may be enhanced by the addition of tracer additives which impart a tint or color to treated components. Such tinting will result in an observable indication of the sufficiency of the component coating. As the tint intensity decreases, the operator will be able to determine if additional coating coverage is required. Further, enhancements may include additives to produce a wider range of component surface characterizations including, but to limited to, corrosion inhibitors, anti-static properties, and the like. As described above, utilization of a glycol-based carrier component to the SAMP composition may enhance crude oil process/service applications.

(25) The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described.

(26) Those skilled in the art will recognize other embodiments of the invention which may be drawn from the illustrations and the teachings herein. To the extent that such alternative embodiments are so drawn, it is intended that they shall fall within the ambit of protection of the claims appended hereto.