(12) United States Patent
`Jan sen et al.
`
`I IIIII IIIIIIII Ill lllll lllll lllll lllll lllll lllll lllll lllll 111111111111111111
`
`US006936112B2
`
`(10) Patent No.:
`(45) Date of Patent:
`
`US 6,936,112 B2
`* Aug. 30, 2005
`
`(54) HEAT EXCHANGER CLEANING PROCESS
`
`(56)
`
`References Cited
`
`(75)
`
`Inventors: Bruce Robert Jansen, Wichita, KS
`(US); Sean Edward Sears, Wichita, KS
`(US)
`
`(73) Assignee: Refined Technologies, Inc., Wichita,
`KS (US)
`
`( *) Notice:
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 196 days.
`
`This patent is subject to a terminal dis(cid:173)
`claimer.
`
`(21) Appl. No.: 10/304,370
`
`(22)
`
`Filed:
`
`Nov. 26, 2002
`
`(65)
`
`(51)
`(52)
`
`(58)
`
`Prior Publication Data
`
`US 2004/0102351 Al May 27, 2004
`
`Int. Cl.7 . ... ... .. ... ... ... ... .. ... ... ... ... ... .. ... ... ... . BOSB 9/00
`U.S. Cl. ..................... 134/19; 134/22.1; 134/22.11;
`134/22.12; 134/22.14; 134/22.15; 134/22.18;
`134/22.19; 134/26; 134/27; 134/30; 134/31;
`134/34; 134/35; 134/36; 134/37
`Field of Search ....................... 134/19, 22.1, 22.11,
`134/22.12, 22.14, 22.15, 22.18, 22.19, 26,
`27, 30,31, 34-37
`
`U.S. PATENT DOCUMENTS
`* 4/1963
`Loucks . . . . . . . . . . . . . . . . . . . . . . 134/22.1
`* 8/1984
`Tedder . ... ... ... ... .. ... ... ... 62/628
`Mehta et al.
`.............. 134/22.1
`10/1994
`Mehta et al.
`................. 134/10
`2/1995
`Krajicek et al.
`........... 134/22.1
`6/1995
`Hashimoto .. ... ... .. ... ... ... 422/27
`1/2000
`9/2001
`Furuta et al.
`. . . . . . . . . . . . . . 134/22.1
`5/2004 Jansen et al. ............... 510/407
`
`3,084,076 A
`4,464,189 A
`5,356,482 A
`5,389,156 A *
`5,425,814 A
`6,017,492 A *
`6,283,133 Bl
`2004/0102351 Al *
`* cited by examiner
`Primary Examiner----Sharidan Carrillo
`(74) Attorney, Agent, or Firm-Shook, Hardy & Bacon
`L.L.P.
`
`(57)
`
`ABSTRACT
`
`Disclosed is a novel process for cleaning and restoring the
`operating efficiency of organic liquid chemical exchangers
`in a safe and effective manner and in a very short period of
`time, without a need to disassemble the equipment and
`without the need to rinse contaminate from the equipment
`after cleaning. Used is a formulation of monocyclic satu(cid:173)
`rated terpene mixed with a non-ionic surfactant package
`specifically suited to oil rinsing. The terpene-based chemical
`is injected into organically contaminated exchangers using a
`novel process involving high-pressure steam to form a very
`effective cleaning vapor.
`
`18 Claims, 7 Drawing Sheets
`
`8
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`98
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`54
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`116
`
`72
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`70
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`114
`
`118
`
`74
`
`86
`
`Page 1 of 16
`
`ULI EXHIBIT 1005
`
`

`

`U.S. Patent
`
`Aug. 30, 2005
`
`Sheet 1 of 7
`
`US 6,936,112 B2
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`Page 2 of 16
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`ULI EXHIBIT 1005
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`U.S. Patent
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`Aug. 30, 2005
`
`Sheet 2 of 7
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`US 6,936,112 B2
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`ULI EXHIBIT 1005
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`

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`U.S. Patent
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`Aug. 30, 2005
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`Sheet 3 of 7
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`US 6,936,112 B2
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`ULI EXHIBIT 1005
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`

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`U.S. Patent
`
`Aug. 30, 2005
`
`Sheet 4 of 7
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`US 6,936,112 B2
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`ULI EXHIBIT 1005
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`

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`U.S. Patent
`
`Aug. 30, 2005
`
`Sheet 5 of 7
`
`US 6,936,112 B2
`
`57
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`
`Page 6 of 16
`
`ULI EXHIBIT 1005
`
`

`

`U.S. Patent
`
`Aug. 30, 2005
`
`Sheet 6 of 7
`
`US 6,936,112 B2
`
`34
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`
`Page 7 of 16
`
`ULI EXHIBIT 1005
`
`

`

`U.S. Patent
`
`Aug. 30, 2005
`
`Sheet 7 of 7
`
`US 6,936,112 B2
`
`8
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`
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`
`Page 8 of 16
`
`ULI EXHIBIT 1005
`
`

`

`US 6,936,112 B2
`
`1
`HEAT EXCHANGER CLEANING PROCESS
`
`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`
`None.
`
`STATEMENT REGARDING FEDERALLY
`SPONSORED RESEARCH OR DEVELOPMENT
`
`None.
`
`BACKGROUND OF THE INVENTION
`
`This invention relates to a process for cleaning the metal
`surfaces of organically contaminated heat transfer equip(cid:173)
`ment in the petroleum and petrochemical industries to
`quickly, safely, and economically.
`The manufacture of chemicals and petroleum products in
`the field of this invention consumes enormous amounts of
`energy. One major refiner-Exxon Mobil--estimates that it
`expends $190 million dollars in energy per month to operate
`its refineries and chemical facilities. See The Lamp, Exxon
`Mobil, Winter 2002. Exxon Mobil production constitutes
`approximately 10.6% of the United States production capa(cid:173)
`bility. Accordingly, one would estimate that more than $1.7
`billion dollars of energy is consumed per month in produc(cid:173)
`ing these organic products in the petroleum refining industry.
`Much of this consumption is due solely to the fouling of
`system components. The petroleum products and chemicals
`produced in this field naturally tend to deposit on contact
`surfaces, causing the equipment to operate sub-optimally.
`This tendency to deposit exacerbates an already difficult
`situation. As an example, in an article published in Chemical
`Engineering Progress, a heat exchanger fouling rate of 0.35
`yr-1 was used which when applied to a particular piece of
`equipment may cause an annual efficiency penalty of 30%.
`O'Donnell, Barna, Gosling, Chemical Engineering Progress,
`June 2001. These figures are consistent with the values
`published by the Tubular Exchanger Manufacturers Asso(cid:173)
`ciation (TEMA) for exchanger fouling resistance. Consid(cid:173)
`ering this 30% penalty, if petroleum refining and chemical
`processing equipment is not cleaned periodically, the result(cid:173)
`ing cost caused by energy losses attributable to fouling could
`exceed $500 million. FIG. 1 illustrates how fouling (the 45
`result of contaminate deposition on exchanger tube walls)
`affects the heat exchange coefficient for an exchanger over
`time. As the heat transfer coefficient decays, more energy
`must be consumed to accomplish the same fluid heating
`through the exchanger.
`Industry has recognized this problem. An article by
`O'Donnell, Barna and Gosling describes a method used to
`compute an optimal cleaning cycle. Industry benchmarks
`such as the "Solomon Index" rate companies on their ability
`to optimize their processes. All companies have established 55
`an energy reduction and process optimization program.
`However, prior to this invention, no realistic alternative was
`available for cleaning heat exchange equipment without
`stopping the process for a substantial amount of time,
`subjecting the equipment to metal deteriorating chemistry 60
`and deleterious thermal cycles. For example, petroleum
`refiners use crude preheat exchangers to increase the tem(cid:173)
`perature of crude oil entering distillation towers. These
`exchangers operate serially with the tower so that if the
`exchangers are removed from service, the crude feed stops, 65
`shutting down the facility. Depending on the nature of the
`crude, condition of associated equipment, operating tern-
`
`5
`
`2
`peratures and flow rate, exchangers can foul at a rate of
`approximately 0.35 Btu/hr Fft2 per year. Typically, refiners
`will continue to operate these exchangers-despite a 30%
`annual reduction in efficiency-until the plant is shut down
`for major maintenance because the cost to shut down the
`facility and clean the exchangers is too great. Using prior art
`procedures, exchangers would be removed from service for
`3 to 5 days for cleaning. During the prior art procedures,
`exchangers are subjected to corrosive chemicals, abrasive
`10 procedures and large thermal excursions, all of which may
`damage the equipment or make it impossible to reassemble.
`Five days of crude unit shutdown may cause a facility to
`irreversibly lose more than $10 million in revenue.
`Historically, using prior art practices, this loss in revenue
`15 was more costly than the savings provided from cleaning.
`Thus, a decision was generally made to continue to operate
`the fouled, inefficient exchangers until efficiency drops so
`low as to make cleaning cost-effective. If the refinery were
`able to clean the exchangers more quickly, this decision
`20 would be reversed and a great amount of money saved.
`Before the present invention, however, this was not a
`possibility.
`Other problems with the prior art systems are environ(cid:173)
`mental in nature. The inefficiency caused by fouling causes
`25 the emissions of carbon dioxide, sulfur dioxide, nitrogen
`oxide and other gases to be increased. Thus, a cleaning
`regimen that improves efficiency also serves to reduce the
`amount of noxious emissions. The prior art methods also
`produce large quantities of hazardous waste. These methods
`30 typically use water circulation procedures where vessels are
`completely filled with water and cleaning chemistry. After
`cleaning, the water tainted with dangerous impurities must
`be specially treated. A typical refinery turnaround using this
`kind of water-circulation cleaning procedure will produce
`35 approximately 500,000 gallons of hazardous material that
`must be disposed of at high cost to the refinery while
`creating a potential ecological nuisance. Likewise, another
`prior art procedure of blasting solid contaminant from the
`exchanger using high pressure water also produces large
`40 quantities of solid hazardous waste that must be specially
`treated.
`The present invention overcomes these disadvantages in
`the prior art methods by injecting a cleaning agent into
`high-pressure steam, and then introducing the steam and
`cleaning agent, which includes terpenes, into a vented
`exchanger. Terpenes have been used in refineries before. A
`liquid-steam method using terpenes is disclosed in U.S. Pat.
`No. 5,356,482 ("the '482"). The methods disclosed in the
`'482, however, are much different than those here. The '482
`50 discloses the use of terpenes for removing dangerous and
`explosive gases from refinery vessels-not for cleaning the
`metal surfaces inside the exchanger for the purpose of
`improving heat transfer properties-as with the present
`invention. The '482 methods are also different in that they
`involve either the circulation of condensed fluid, or the
`injection of cleaner into a water circulation. These methods
`further require the vessel to be sealed under pressure and to
`cool-a technique that has been known to occasionally
`cause catastrophic collapse. Unlike the '482 methods, rins(cid:173)
`ing condensation is not required. Thus, there is no need to
`reduce the temperature of the vessel to create the necessary
`condensation. Further, the present invention does not use a
`microemulsion of cleaning chemical, or rely on mechanical
`rinsing. Rather, the present invention uses a fully concen(cid:173)
`trated solution of chemical agent in the vapor form to
`accomplish the cleaning. Another important difference is
`that the process of the present invention occurs in a fully
`
`Page 9 of 16
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`ULI EXHIBIT 1005
`
`

`

`US 6,936,112 B2
`
`10
`
`3
`vented exchanger. This eliminates any possibility of cata(cid:173)
`strophic collapse.
`
`SUMMARY OF THE INVENTION
`
`The present invention is a method of cleaning a contami(cid:173)
`nated vessel, comprising the steps of (i) providing a steam
`source; (ii) providing a surfactant source; (iii) providing an
`organic solvent source; (iv) delivering steam from said
`steam source to said vessel; (v) introducing the organic
`solvent from the organic solvent source into the steam
`delivered; (vi) introducing a surfactant from said surfactant
`source into the steam delivered; (vii) removing vaporous
`effluent from said vessel; and (viii) removing contaminant
`from said vessel without the use of hydro-blasting.
`More specifically, the process involves taking the
`exchanger (or exchangers) to be cleaned out of service by
`blocking it in, injecting a terpene and a surfactant package
`into high-pressure steam, and introducing the steam and
`chemistry mixture into the equipment to be cleaned. The
`cleaner is particularly well suited to cleaning large surface
`areas with relatively little cleaning fluid. The equipment
`includes a system of pumps, T-fittings and injector nozzles
`needed to vaporize and accurately control the volumetric
`ratios of chemical vapor and steam. The cleaner injected into
`the steam ideally includes a formulation including a mono(cid:173)
`cyclic saturated terpene mixed with a non-ionic surfactant
`package.
`The process may be used to clean (i) the shell and tube
`sides of one exchanger at once, (ii) the shell and tube sides
`of two exchangers at once, (iii) one side of one exchanger,
`or (iv) one side of one exchanger simultaneously with one
`side of a second exchanger.
`
`BRIEF DESCRIPTION OF THE DRAWING
`
`4
`when a regular maintenance program using the disclosed
`process is established-the area below a curve computed
`using a regular cleaning regimen and above the curve
`without a cleaning regimen. A basic net present value
`5 calculation can be used to determine a most optimal cleaning
`cycle. A curve that identifies a 6 month period as the optimal
`cleaning interval when comparing cost to clean versus loss
`in efficiency is shown in FIG. 4. This interval is much shorter
`than before possible with the prior art methods in which
`delays of 24 months are typical.
`Regular cleaning is possible because the present invention
`enables the exchangers to be cleaned much more quickly
`than with the prior art methods. Because the exchangers are
`cleaned much more quickly, the refinery is able to boost
`15 efficiency by defouling while minimizing downtime. The
`invention does not require equipment disassembly, so equip(cid:173)
`ment requiring cleaning can be cleaned without having to
`remove the equipment from a feed stream. The invention
`does not utilize corrosive chemicals or abrasive techniques
`20 to work effectively so that equipment will not suffer unpre(cid:173)
`dictable damage during the cleaning process. Using the
`disclosed invention, the aforementioned crude preheat
`exchangers can be cleaned without disconnection from the
`feed train in 2 to 4 hours. During the cleaning process the
`25 tube bundles are not removed and the temperature of the
`exchangers remains elevated. In fact, the elevated tempera(cid:173)
`ture of the equipment serves to aid the cleaning process.
`The efficiency and effectiveness of the disclosed invention
`enables completely new operating paradigms. Individual
`30 pieces of equipment in a feed stream foul at different rates.
`Therefore, chemical producers achieve the greatest effi(cid:173)
`ciency gain for the least cleaning expense when targeted
`equipment is cleaned. With the prior art methods, cleaning
`required entire plants of equipment to be completely shut
`35 down for cleaning and maintenance. After shut down, it is
`found that some equipment is quite fouled and other equip(cid:173)
`ment is relatively clean. Nevertheless, because the plant is
`shut down anyway, all the equipment is cleaned-including
`equipment that is relatively clean. The disclosed invention,
`40 however, allows the most fouled ( or capacity constraining)
`equipment to be cleaned on a more frequent basis without
`necessarily cleaning other less-fouled equipment. Preheat
`crude exchangers are installed serially in the distillation
`crude system. There may be as many as 60 exchangers
`45 aligned in series so that each exchanger feeds the next. The
`exchangers foul at different rates, so that at any point one or
`two exchangers affect the performance of the entire feed
`train. The invention of the present invention allows one of
`these most-fouled exchangers to be cleaned while the other
`exchangers remain in service during the 2 to 4 hour cleaning
`process. Thus, cleaning time and resources are not wasted on
`the relatively-clean exchangers. Because the plant does not
`have to be shut down, operating efficiency of the facility is
`dramatically increased.
`These technologies also enable two different exchangers
`to be cleaned in series, as can be seen in FIG. 7. As shown
`in the figure, both sides of two heat exchangers may be
`cleaned at the same time. Like the selective cleaning of a
`single exchanger as discussed above, selectively cleaning
`60 the two most-fouled exchangers in a series reduces resources
`wasted in cleaning the other relatively clean exchangers,
`thus increasing the operating efficiency of the facility.
`The process of the present invention also allows for
`cleaning one side of an exchanger at a time. Exchangers
`65 each have two operating sides, with one side often fouling
`at a faster rate than the other. The process of the present
`invention allows the user to clean only the most-fouled side
`
`The present invention is described in detail below with
`reference to the attached drawing figures, wherein:
`FIG. 1 is a graph showing how fouling affects the heat
`transfer coefficient for a heat exchanger over time.
`FIG. 2 is a graph showing how refinery operating expense
`is reduced when a regular maintenance program using the
`disclosed process is established-the area below a curve
`computed using a regular cleaning regimen and above the
`curve without a cleaning regimen.
`FIG. 3 is a graph comparing the performance of uncleaned
`versus cleaned exchangers on the same system.
`FIG. 4 is a graph comparing the cost of cleaning to the
`loss due to inefficiency due to not cleaning.
`FIG. 5 is a schematic diagram showing the injection 50
`equipment of the present invention.
`FIG. 6 is a schematic diagram showing the administration
`of the cleaning process of the present invention in a single
`shell-and-tube exchanger.
`FIG. 7 is a schematic diagram showing the administration
`of the cleaning process of the present invention in cleaning
`two exchangers at once.
`
`55
`
`DETAILED DESCRIPTION OF THE
`INVENTION
`
`The present invention solves the problems present in the
`prior art methods.
`First, by enabling the exchangers to be cleaned more
`regularly, the resulting unfouled exchangers operate more
`efficiently, with less heat input. Thus, operating expense is
`reduced. FIG. 2 shows how operating expense is reduced
`
`Page 10 of 16
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`ULI EXHIBIT 1005
`
`

`

`US 6,936,112 B2
`
`5
`of an exchanger. The other side of the exchanger is able to
`remain in service.
`It is also possible to simultaneously clean single sides of
`two different exchangers in series using the present inven(cid:173)
`tion. For example, the shell side of one heat exchanger may
`be cleaned at the same time as the shell side of another heat
`exchanger in the series while the tube sides of these
`exchangers are not cleaned. It is also possible to clean two
`tube sides of two different exchangers in series and not the
`shell sides. FIG. 3 charts the effects of these cleaning
`methods on a bank of 8 exchangers, where only the tube
`sides of two exchangers were cleaned. As can be seen from
`the figure, cleaning the tube sides of two different exchang(cid:173)
`ers in series greatly improves overall operating efficiency.
`In addition to improving overall efficiency, the present
`invention is also more environmentally friendly. Again,
`before the present invention, refineries would continue to
`operate heavily-fouled equipment in order to avoid the
`expense of a complete shut-down. The selective cleaning
`methods of the present invention avoid this dilemma-by
`enabling more frequent cleanings. Because the equipment is
`cleaned more often, it operates more efficiently. This reduces
`the amount of heat/energy required to operate the refinery.
`The generation of heat/energy required to operate the refin(cid:173)
`ery creates the emissions of toxins such as carbon dioxide,
`sulfur dioxide, nitrogen oxide and other gases. A reduction
`in energy consumption of 30% could reduce the total emis(cid:173)
`sions of these toxic gases by 6%. Furthermore, the process
`of the present invention does not require circulation or
`rinsing. Instead, by-products of the present invention may be
`processed as regular chemical feed by the refiner since they
`contain a preponderance of feed material. Therefore,
`because no water circulation procedures are necessary, no
`hazardous waste is produced that must be specially treated.
`In addition to protecting the environment, the disclosed
`process also protects refinery workers from hazardous work(cid:173)
`ing conditions. Prior to this invention, workers were
`required to disassemble heavy equipment and then clean it
`by hydro-blasting. Workers would sometimes be crushed or
`otherwise harmed by the heavy equipment involved.
`Additionally, these workers would potentially be exposed to
`the dangerous chemicals used.
`An additional benefit of the process of the present inven(cid:173)
`tion is its ability to clean large equipment using a volume of
`cleaning agent equivalent to only 1-5% of the volume of the
`vessel. Also, the time needed to perform the cleaning
`process is dramatically less than current cleaning processes
`in the industry. By cleaning with less chemical, more
`thoroughly, and in a shorter period of time, the disclosed 50
`process significantly improves cleaning efficiency while
`eliminating the need for dangerous disassembly of equip(cid:173)
`ment.
`The present invention accomplishes the above described
`benefits using a naturally occuring organic solvent as the
`cleaning agent. The cleaning agent is injected directly into
`high-pressure steam lines already present in the refinery's
`system. Once injected, the cleaning agent is vaporized, and
`allowed to clean all surfaces inside the vessel in a very short
`period of time. The cleaning agent is also unique because it
`utilizes a surfactant package that improves the detergency
`(solvency strength) of the product allowing it to be more
`oil-soluble. This enables the users of the process to "rinse"
`using the refinery's hydrocarbon process stream rather than
`the water rinse process used in prior art methods.
`This is accomplished using a cleaning agent having two
`ingredients. The first is a terpene. The term "terpenes"
`
`6
`traditionally applied to cyclic hydrocarbons having struc(cid:173)
`tures with empirical formula C10H16 which occur in the
`essential oils of plants. Knowledge of the chemistry of the
`terpene field has developed and compounds related both
`5 chemically and biogenetically to the C10H16 carbons have
`been identified. Some natural products have been synthe(cid:173)
`sized and other synthetic compounds resemble known ter(cid:173)
`pene structures. Consequently, the term "terpenes" may now
`be understood to include not only the numerous C10H16
`10 hydrocarbons, but also their hydrogenated derivatives and
`other hydrocarbons possessing similar fundamental chemi(cid:173)
`cal structures. These hydrocarbons may be acyclic or cyclic,
`simple or complex, and of natural or synthetic origin. The
`cyclic terpene hydrocarbons may be classified as
`15 monocyclic, bicyclic, or tricyclic. Many of their carbon
`skeletons have been shown to consist of multiples of the
`isoprene nucleus, C5H8 .
`Generally, the terpene selected could be acyclic, bicyclic,
`or tricyclic. Examples of acyclic terpenes that might be used
`20 are geraniolene, myrcene, dihydromycene, ocimene, and
`allo-ocimene. Examples of monocyclic terpenes that might
`be used are p-menthane; carvomethene, methene, dihydrot(cid:173)
`erpinolene; dihydrodipentene; a-terpinene; y-terpinene;
`a-phellandrene; pseudolimonene; limonene; d-limonene;
`25 1-limonene; d,1-limonene; isolimonene; terpinolene; isoter(cid:173)
`pinolene; ~-phellandrene; ~-terpinene; cyclogeraniolane;
`pyronane; a-cyclogeraniolene; ~-cyclogeraniolene;
`y-cyclogeraniolene; methyl-y-pyronene; l-ethyl-5
`5-dimethyl-1,3-cyclohexadiene; 2-ethyl-6,6-dimethyl-1,3-
`30 cyclohexadiene; 2-p-menthene 1(7)-p-methadiene; 3,8-p(cid:173)
`menthene; 2,4-p-menthadiene; 2,5-p-menthadiene; 1(7),4
`(8)-p-methadiene; 3,8-p-menthadiene; l,2,3,5-tetramethyl-
`1-3-cyclo hex adie ne; 1,2,4, 6-te trame thyl-1,3-
`cyclohexadiene; 1,6,6-trimethylcyclohexene and 1,1-
`35 dimethylcyclohexane. Examples bicyclic terpenes that
`might be used are norsabinane; northujene;
`5-isopropylbicyclohex-2-ene; thujane; ~-thujene; a-thujene;
`sabinene; 3, 7-thuj adiene; norcarane; 2-norcarene;
`3-norcarene; 2-4-norcaradiene; carane; 2-carene; 3-carene;
`40 ~-carene; nonpinane; 2-norpinene; apopinane; apopinene;
`orthodene; norpadiene; homopinene; pinane; 2-pinene;
`3-pinene; ~-pinene; verbenene; homoverbanene;
`4-methylene-2-pinene; norcamphane; apocamphane; cam(cid:173)
`pane; a-fenchane; a-fenchene; sartenane; santane; norcam-
`45 phene; camphenilane; fenchane; isocamphane; ~-fenchane;
`camphene; ~-fenchane; 2-norbornene; apobornylene;
`bornylene; 2,7,7-trimethyl-2-norbornene; santene; 1,2,3,(cid:173)
`trimethyl-2-norbornene; isocamphodiene; camphenilene;
`isofenchene and 2,5,-trimethyl-2-norbornene.
`The terpene normally used, and most preferred as the first
`ingredient in the cleaning agent of the present invention is a
`monocyclic saturated terpene that is rich in para-menthane
`(C 10H20). Para-menthane has a molecular weight of
`140.268. This active ingredient includes both the cis- and
`55 trans-isomers. Common and approved synonyms for para(cid:173)
`menthane include: l-methyl-4-(1-methylethyl)-cyclohexane
`and l-isopropyl-4-methylcyclohexane. Para-menthane is all
`natural, readily biodegradable by EPA methods, and non(cid:173)
`toxic by OSHA standards. Monocyclic saturated terpenes,
`60 however, are not the only compounds that may be used as
`the active ingredient of the cleaning agent. Other naturally
`occuring terpenes, such as (i) monocyclic unsaturated iso(cid:173)
`prenoids such as d-limonene (C10H16), (ii) bi-cyclic pine
`terpenes such as -pinene & -pinene, or (iii) any combination
`65 of monocyclic and bi-cyclic terpenes could also be used.
`A second ingredient in the cleaning agent is an additive.
`The additive of the present invention is a non-ionic surfac-
`
`Page 11 of 16
`
`ULI EXHIBIT 1005
`
`

`

`US 6,936,112 B2
`
`7
`tant package which enhances detergency, wetting, oil
`solubility, and oil rinsing. The first major constituent of the
`surfactant package includes a linear alcohol ethoxylate
`(C12-C15) with an ethoxylated propoxylated end cap. This
`linear alcohol ethoxylate greatly enhances the detergency or 5
`cleaning power of the cleaning agent formulation. Linear
`alcohol ethoxylates are also more environmentally friendly
`than more traditional surfactants. They exhibit good
`biodegradation, and aquatic toxicity properties. Another
`major constituent of the cleaning agent surfactant package is 10
`a fatty alkanolamide primarily consisting of amides and tall
`oil fatty N,N-bis(hydroxyethyl) This fatty alkanolamide
`primarily aids in oil rinsing, oil solubility, and wetting. The
`combination in the proper ratios of these two classes of
`surfactants achieves the desired enhancements of the clean- 15
`ing agent formulation. The following non-ionic surfactants
`with an HLB range of 6.0-10.5 are also acceptable as an
`additive package but not limited to (i) nonylphenol
`polyethoxylates, (ii) straight Chain linear alcohol
`ethoxylates, (iii) linear alcohol ethoxylates with block
`copolymers of ethylene and propylene oxide, (iv) oleamide
`DEA, or (v) diethanolamine. Of course, one skilled in the art
`would recognize that other additives could be used which
`would still fall within the scope of the invention.
`The formulation of the cleaning agent of the present 25
`invention is effective at any of the following composition
`ranges by using a combination of the acceptable chemistries
`from above:
`
`8
`exchanger when open and a tube-side outgoing valve 26
`allows flow out. Similarly, a shell side feed in valve 28 and
`feed out valve 30 allow flow through the shell side when
`open. In order to block in the exchanger, valves 24, 26, 28,
`and 30 are closed. This stops the flow of any processing
`fluids, blocking the exchanger in. The fluids remaining in the
`now-blocked-in exchanger are then removed from the
`exchanger by simple draining.
`Once tube and shell sides of the exchanger have been
`drained and blocked in, the source of stream and venting
`systems are tapped into the exchanger. Referring again to
`FIG. 6, each of feeds 16, 18, 20, and 22 have bleeder
`connections at 32, 34, 36, and 38, respectively. Bleeder
`connections 32, 34, 36, and 38 enable the user to gain fluid
`access to exchanger 10 after it is blocked in so that steam
`may be introduced and then vented.
`Steam is tapped into the exchanger using bleeder connec(cid:173)
`tions 32 (associated with the tube side in-feed 16) and 36
`(associated with the shell side out-feed 22). A first source of
`20 steam 40 may usually be tapped into in-feed 16 by simply
`removing a cap (not pictured) that exists on most bleeder
`connections. This same procedure is also used to attach a
`second source of steam 42 to the shell side out-feed 22
`through bleeder connection 36. First and second sources of
`steam, 40 and 42 respectively, are normally obtained from
`preexisting steam lines in the plant. The lines selected
`should have steam temperatures of at least 330 degrees
`Fahrenheit, and are attached to bleeders 32 and 36 in a
`manner well known to those skilled in the art. Ideally, the
`30 line temperatures should be between about 350 to 450
`degrees Fahrenheit. The typical 150 psi refinery steam line
`will work effectively, however, super-heated 40 psi steam
`lines, which deliver steam at temperatures in excess of 400
`degrees Fahrenheit, may be used as well. The injected steam
`35 increases internal temperatures within the exchanger.
`A first source of cleaning agent 44, which is to be used
`later on in the process, Is tapped into steam line 40 upstream
`of the bleeder connection 32. The introduction of cleaning
`agent is made possible by joining source of steam 40 with
`40 cleaner source 44.
`The administration of both steam and cleaner are accom(cid:173)
`plished using an administrator 11. The details regarding
`administrator 11 of the present invention are shown in FIG.
`5. FIG. 5 discloses that steam 40 and cleaner 44 sources
`45 joined at a T-junction 35. Such T-junctions are standard
`plumbing, and acceptable embodiments are readily available
`to one skilled in the art. The refinery steam hose (not shown)
`selected as steam source 40 for use in the cleaning process
`is attached to steam conduit using a standard connector 51.
`50 Conduit 37 transmits the steam under pressure to a first side
`of junction 35. Between steam source 40 and junction 35 on
`conduit 37, a gate valve 43 serves to either open or shut off
`the source of steam 40 after the hose is attached. Immedi-
`ately downstream, a check valve 47 allows flow in the
`downstream direction only. This prevents back flow of
`cleaning chemical or effluent into steam source. Interposed
`on conduit 39 between cleaner source 44 and junction 35 are
`gate valve 45 and check valve 49. Gate valve 45 is used to
`either allow or shut off the flow of cleaner from source 44.
`Check valve 49 allows flow in the downstream only to
`prevent the back flow of steam into the cleaner container. A
`standard elbow 55 is used to converge conduit 37 and 39 into
`junction 35. After steam and cleaner conduits, 37 and 39
`respectively, meet up at junction 35, their collective flows
`65