CA2218029A1 - Method and apparatus for measuring deposits in pipelines - Google Patents
Method and apparatus for measuring deposits in pipelines Download PDFInfo
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- CA2218029A1 CA2218029A1 CA 2218029 CA2218029A CA2218029A1 CA 2218029 A1 CA2218029 A1 CA 2218029A1 CA 2218029 CA2218029 CA 2218029 CA 2218029 A CA2218029 A CA 2218029A CA 2218029 A1 CA2218029 A1 CA 2218029A1
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- 238000000034 method Methods 0.000 title claims abstract description 17
- 230000008021 deposition Effects 0.000 claims abstract description 34
- 239000012530 fluid Substances 0.000 claims abstract description 25
- 238000005259 measurement Methods 0.000 claims abstract description 20
- 239000006260 foam Substances 0.000 claims abstract description 15
- 238000013500 data storage Methods 0.000 claims abstract description 7
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- 238000000151 deposition Methods 0.000 description 30
- 230000004907 flux Effects 0.000 description 7
- 239000003921 oil Substances 0.000 description 7
- 241000282887 Suidae Species 0.000 description 6
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- 238000004458 analytical method Methods 0.000 description 2
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- 238000012935 Averaging Methods 0.000 description 1
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Classifications
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/26—Oils; Viscous liquids; Paints; Inks
- G01N33/28—Oils, i.e. hydrocarbon liquids
- G01N33/2811—Oils, i.e. hydrocarbon liquids by measuring cloud point or pour point of oils
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N17/00—Investigating resistance of materials to the weather, to corrosion, or to light
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/26—Oils; Viscous liquids; Paints; Inks
- G01N33/28—Oils, i.e. hydrocarbon liquids
- G01N33/2835—Specific substances contained in the oils or fuels
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- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- General Health & Medical Sciences (AREA)
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- Physics & Mathematics (AREA)
- Immunology (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Physics & Mathematics (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Food Science & Technology (AREA)
- Medicinal Chemistry (AREA)
- Ecology (AREA)
- Environmental & Geological Engineering (AREA)
- Environmental Sciences (AREA)
- Biodiversity & Conservation Biology (AREA)
- Length Measuring Devices With Unspecified Measuring Means (AREA)
Abstract
An apparatus for measuring deposits in pipelines is disclosed. The apparatus consists of a fluid immersible body being sized and shaped to be insertable into a pipeline to at least partially block a flow of fluid past said body in said pipeline. Most preferably, the body is made from a compressible foam portion surrounding a fluid tight electronics chamber. Attached to the compressible body are sensors to measure a thickness of any deposits on the inside of the pipeline. The sensors are connected to data storage means to record the measurements. In a preferred embodiment, the thickness is detected by proximity sensors which sense the proximity of the metal pipe wall. The device is most preferably used for measuring wax deposit thickness. In another embodiment of the invention, there is provided a method for measuring wax deposition rates in pipelines comprising passing the apparatus for measuring deposit thickness through the pipeline on a first occasion, passing the same apparatus through the pipeline on a second occasion, and comparing the measured thicknesses to calculate a rate of change of deposit thickness over time. An another embodiment of the invention, there is provided a method of measuring deposits in pipelines comprising placing a sensing device in the pipeline, passing the sensing device through the pipeline, measuring the deposits in the pipeline and recording the measurements of the deposits in an electronic format.
Description
PN File No.: NEI018/JTN
Title: Method and Apparatus for Measurement of Wax Deposits FIELD OF THE INVENTION
s This invention relates generally to the field of hydrocarbon recovery and transportation. In particular this invention relates to measuring deposits that form on pipeline equipment, such as pipeline walls during the transportation of hydrocarbons such as waxy crude oils through such equipment.
BACKGROUND OF THE INVENTION
The production of oil and gas is important for both economic and strategic reasons. The recovery of oil or gas from a particular reservoir is determined by the economics of operation. If the revenue is less than the operating costs, then the well will be 15 either shut in (to wait for higher prices, better production technology, etc.) or the well may be plugged with concrete and abandoned. The economics of recovery are related to how much (volume) can be drawn up out of the formation. Pipeline deposits, which constrict flow, can seriously negatively affect such 20 economics. In some environments such as offshore pipelines and tubulars each incident of plugging due to wax deposition can cost millions of dollars. It has been recently reported that 17 such incidents occurred in the Gulf of Mexico during a one year period.
To date there is no reliable technique to predict rates of wax 25 deposition. Lab measurements seldom correlate to measured rates in the field. Allelllpls have been made in the past to assess the factors which control the solubility of the parafffin in crude through analytical measurements and thermodynamic models.
However, wax deposition and plugging of pipelines can be less 30 severe in highly waxy crudes and more severe in less waxy crudes. There are pipelines which carry extremely waxy crude and do not require any wax deposit removal.
A reliable characterization and prediction technique for wax deposition could allow optimization of transporVprocess parameters to minimize capital and operating expenses relating to hydrocarbon recovery. Such a technique could also reduce development and operating costs and allow economic oil recovery from marginal oil pools.
s A key problem limiting prior art techniques is the diffficulty of obtaining wax deposition rate data under actual field conditions.
Typically wax deposition rate data is not available for pipelines.
Operators can only get indirect and imprecise observations such as pipeline displacement volume or friction factor or deposition rate 10 data at the inlet or outlet where access to the pipeline can be obtained. Key information about deposit thickness and roughness cannot be determined. As a result there exists no reliable analytical model to predict wax deposition, because the models being used cannot be checked against field measured data to evaluate the correlation between the effects predicted by the model and the actual field results.
The lack of quantitative field data is a very significant problem. Lab and flow loop wax deposition experiments are of limited value because they cannot be benchmarked against actual 20 field measurements. The lack of field data has prevented the development of accurate wax deposition rate models.
Furthermore, assessment and development of improved control strategies (inhibitors, seeding, etc.) or improved remedial strategies, (pigging, hot water, hot oil, solvents, dispersants, etc.) iS restricted without a means to obtain accurate wax deposition rate measurements in the field.
Thus, there is a need to measure wax deposition rates in operating pipelines for the development of improved wax models, controls and evaluation of remedial technology.
Various pipeline parameters have been measured in the past by use of devices known as "pigs". These are objects which are pushed along by the fluid flow in the conduit and which may carry out certain functions such as scraping wax build-up, or monitoring pipeline integrity through sensors mounted in the pig (the so-called "smart pigs"). However, such pigs have not included sensors capable of sensing information about any wax depositions formed in the pipeline, due to the properties of the wax, which include its soft and sticky consistency, its transparency to conventional sensing signals and other factors.
These smart pig devices consist of, for example an s ultrasonic sensor, and a data transmission module mounted in a pig. The pig is displaced through the pipeline by pumping fluid into the pipeline. Typically these pigs are large and rigid and cannot pass through restrictions. The pipeline must be extremely clean (i.e., no accumulated deposits whatsoever) before the owner of the 10 smart pig would risk running the pig into the pipeline. These pigs are very expensive to operate (50K$ per run) so they are usually only run when required by regulatory agencies.
BRIEF SUMMARY OF THE INVENTION
What is desired is a smart pig that is capable of measuring 15 wax deposition in a field environment. Therefore there is provided according to one aspect of the present invention a smart pig for measuring wax deposits in a pipeline or conduit. The requirements for measuring wax deposition rates are quite different from the typical smart pig application. A pig according to 20 the present invention will be conflgured to have one or more of the following attributes:
1) to be able to pass through a variable (and unknown) pipeline inner diameter (due to accumulated deposit) 2) to measure a soft deposit precisely 3) to be relatively low cost to operate, so multiple runs can be used to measure wax accumulation rates 4) to measure the temperature profile in the pipeline to facilitate the use of thermodynamic calculations in predictive techniques, and 5) measure a pressure differential across the pig to facilitate the integrity of the wax deposit being evaluated.
Another aspect of the present invention is to provide a pig with a flexible body to permit it to fit through partially obstructed pipelines, and which includes sensors to measure various parameters relating to pipeline conditions, the state of the pig itself or wax characteristics and a data storage package to record the data being measured. In a further aspect a telecommunications package is provided to permit data to be transmitted in real time.
Another aspect of the present invention is to provide a s means to measure the thickness of the wax deposits in a pipeline over the entire length of the pipeline so that wax deposit accumulation rates can be determined. While some of the most important data is likely to be that of the deposit thickness, other parameters can also be measured to obtain relevant data 10 according to the present invention. Parameters such as deposit roughness, deposit hardness, deposit composition, suspended waxy solids characteristics, concentricity/eccentricity/orientation of deposits, temperature profiles, heat fluxes are also comprehended by the present invention. This data is useful for bench marking deposition rate calculations with real data to build more accurate deposition models and to provide a more accurate predictive technique.
For instance, one common wax deposition model postulates that wax solids in the oil adhere to the pipe walls. Information 20 about wax deposition profiles at pipeline curves provided by the present invention could help verify/disprove this theory.
Furthermore, wax deposit data produced according to the present invention could be extremely helpful to calibrate pipeline hydraulic models.
Wax deposit data generated according to the present invention will also be useful to examine the effects of various chemical treatments. For instance, a number of chemical products are claimed to reduce deposition rates and/or result in softer deposits. At this time there is no practical way to verify the truth of 30 these claims except by indirect means which are generally unreliable. Thus, wax deposit data will also be useful to optimize the effects of various chemical treatments and facilitate the development of better products.
The apparatus according to the present invention will also 35 be useful to measure the wax deposit accumulation rate for remedial processes such as changes in flow line temperature, flow line configuration and variable suspended solids characteristics (i.e., seeding). In this manner the present invention provides real time field measurements of the effect of various control options on the rate and incidence of wax deposition.
Therefore, there is provided according to one aspect of the present invention an apparatus for measuring wax deposits comprising:
a soft pig which is transported through a pipeline by a fluid flowing in said pipeline, said soft pig being capable of passing through a partially restricted pipeline diameter, a means carried by said soft pig to measure a thickness of the wax deposits in said pipeline.
According to additional aspects of the present invention, the soft pig further includes:
a means to measure and locate an inside wall of said pipeline;
a means to measure a temperature of the fluid adjacent to said soft pig;
a means to locate said pig within said pipeline;
a means to determine a hardness of said wax deposits;
a means to capture samples of said wax deposits;
a means to measure an orientation of said wax deposits;
a means to determine a roughness of said wax deposits;
a means to save said measurement data electronically;
a means to communicate said data to a remote data storage module;
a means to calculate wax deposition rates by comparing total accumulation of wax deposits on successive pig trips;
a means to determine deposit composition and melting~0 point and or dissolution temperature from said samples;
a means to calculate heat fluxes and temperature gradients using the temperature profile data a means for numerical calculation of said wax deposit characteristics using said sensors and probes comprising external~5 computational devices and software Furthermore said apparatus is most preferable small, CA 02218029 1997- lO- lO
inexpensive, robust and portable so that it can be readily transported to remote locations to provide measurements in the oilfield.
s BRIEF DESCRIPTION OF THE DRAWINGS
Reference will now be made, by way of example only, to preferred embodiments of the invention as illustrated in the accompanying drawings and in which:
Figure 1 illustrates a schematic of the invention, a soft 10 pipeline pig to measure deposits on a pipeline wall.
Figure 2 illustrates an example of a theoretical measured deposit thickness on two consecutive runs according to the present invention.
Figure 3 illustrates a calculated wax deposition rate.
Figure 4 illustrates a measured temperature profile in the pipeline.
Figure 5 illustrates a calculated heat flux and a calculated temperature gradient at the pipeline wall.
DETAILED DESCRIPTION OF THE PREFERRED
This patent applies to the measurement and prediction of waxy crude properties. As waxy crudes cool down or lose volatiles, during transport from the reservoir to the refinery, parafffin wax will precipitate. This precipitation may occur on the pipeline 25 inner walls or at other locations in the transportation system such as on pumps, rods, valves and the like. The precipitated parafffins cause numerous problems. For example they cause flow obstructions and even plug off pipelines; they cause poor pumpability due to high viscosity and cause a difficulty breaking 30 water/oil emulsions.
Reference is made in this invention to measurement of "deposits" in pipelines. While the primary deposits being measured are wax deposits, it will be understood that other deposits can also be measured such as scales and even coated 35 liners and the like, for thickness and other properties. Thus, the -present invention provides data from inside pipelines about flow restriction, and in particular waxy flow restrictions.
The present invention provides a quantitative approach to understand the processes affecting the waxy crude characteristics.
5 This invention is directed to the measurement of wax deposits and the use of this measured information in the understanding of the dynamics of wax deposition processes in pipelines. The term pipeline and conduit in this application will be understood to mean any closed tube through which a fluid may be pumped and which 10 therefore may carry a pig through its bore. The terms pipeline, conduit and flow line mean any pipe or conduit through which fluids flow and includes tubing strings, casings, above or below grade pipes, underwater pipes, inter-rig pipes or pipelines, hoses, and other fluid passage conduits used in the transportation of hydrocarbons.
Turning to Figure 1, there is shown an intelligent soft pig 10 according to the present invention. The pig 10 is used to characterize and measure wax deposits on the walls of pipelines and flow lines as more fully described below.
The pig 10 has a two-part body including a first portion 12 and a second portion 14. Carried in the pig 10 are the following components, sensors to detect deposit thickness and hardness 16, sensor(s) to detect pig location and orientation (up/down) 18, sensors to detect fluid temperature 20, sensors to detect pipeline inner diameter (ID) 22, and sensors 24 to detect a pressure drop across the pig 10. Deposit thickness, hardness, fluid temperature pipeline ID and pressure sensors are immersed in the pipeline fluid, as shown, while the location and orientation sensors are located inside a pressure capsule 44 located within the first body portion 12.
As shown in the drawing the pipeline inner diameter sensor 22 may take the form of a displacement sensor, such as manufactured by Kaman Instrumentation of Colorado Springs Colorado. The measurements of the inner diameter sensor 22 can 35 be related to the measurements of the thickness sensor 16 to determine the inner diameter of the pipeline The second body portion 14 consists of a sensor mounting structure 30 which in the preferred embodiment is mounted on a springleaf 32. The springleaf 32 is comprised of three spring arms 34a 34b and 34c as shown. It will be appreciated that more or s fewer spring arms can be used and the number desired will depend on the number of sensors used, the degree of redundancy designed into the device and the degree of accuracy required in locating the sensors about the inner circumference of the pipeline being measured. More specifically more sensors around the inner 10 circumference will provide more accurate information about the deposits on the inner circumference about the inner pipeline wall.
However it is believed that three sensors will provide sufficient information.
Turning to the arm 34a, it will now be more particularly described. While the description is in reference to spring arm 34a it is generally applicable also to spring arms 34b and 34c. The spring arm 34a is of a bowed configuration as shown and includes a wax thickness sensor 16 at its outermost point. The natural or rest position the arm 34a is at a position spaced outwardly of the 20 inner diameter of the pipeline 36. The spring arm 34a is compressed to be inserted into the pipeline 36 and therefore the spring arm 34a is urged into contact with the inside surface of the pipeline 36. In this way the spring arm 34a is used to position the wax deposit sensors 16 against the pipeline ID, or against any wax 25 deposit 38 which is present. The tension in the spring 34a is adjusted to vary the penetration of the sensors 16 into the wax deposit 38 and thus obtain data on wax deposit hardness.
Alternatively the sensors 16 may be mounted in sensor mounts 30 having smaller or larger footprints to vary penetration based on 30 deposit 38 hardness and also resolve smaller details of deposit 38 roughness. The wax deposit thickness sensors 16 preferably use either an inductive bridge or a Colpits oscillator as a means to detect the proximity to the steel substrate (i.e. pipewall 36) such as those manufactured by Kaman Instrumentation of Colorado 3s Springs, Colorado. It will be appreciated by those skilled in the art that other types of sensors might also be used, provided that they CA 022l8029 l997- lO- lO
are able to detect the separation distance between a fixed point and the pipeline wall, to obtain a measure of the wax deposit 38 thickness.
It can now be appreciated that with three spring arms 34 the 5 deposit 38 thickness will be tracked at three points around the inner circumference of the pipeline 36 generally separated by 120 degrees. If more data points are required, for example because the deposit thickness varies about the circumference, then more arms and more sensors can be used.
The electronic signals from the outside sensors 16, 20 and 22 are routed via cables 40 through a electrical feedthrough pressure seal 42 into a clean dry pressure chamber 44 which holds the signal conditioning electronics 46 and the data acquisition electronics 48. Some sensors may require the cables 40 be in the form of coaxial wires while others might require twisted pairs, but both are comprehended by the present invention.
Further sensors (up/down orientation, inertial/gps locator) 18 would also be placed inside the clean pressure chamber 44.
Signal conditioning unit 46 include filters, and/or current to 20 voltage conversion prior to the data acquisition 48, as well as shielding and ground connections. The data acquisition system 48 is most preferably a speed - high precision (i.e. 16 bit system) electronic instrument with adequate memory capacity to collect the sensed information. Averaging/smoothing of the data could be 25 achieved via software or hardware means either in the data acquisition package 48 or in a remote station where the sensed data is down loaded. Data processing would also be used to filter out recognizable magnetic anomalies such as pipe welds.
The pressure chamber 44 is encapsulated in a soft foamed 30 rubber or like material 50, having a low durometer rating. The pressure chamber 44 is preferably held within the foam 50 by flexible oversize rubber caps 52 screwed or bolted to the ends of the pressure chamber by fasteners 54. It will be appreciated that other ways of attaching the foam 50 to the pressure chamber 44 3s could also be used.
Most preferably the foam 50 will be removably attached to the pressure chamber 44 to form the pig 10. In this manner, the foam 50 would be disposable and could be discarded after each run. The same pressure chamber 44 and sensors and electronics could then be inserted into different sized foam tubes 50 to readily s adapt the pig 10 to different pipeline diameters.
It will be appreciated that the use of a foam body 50 permits the pig 10 to pass through a pipeline of varying diameter due to, for example, wax deposition. The foam must be stiff enough, on the one hand, to form a reasonable seal with the pipeline wall. In 10 this way the pig 10 will be pushed along by hydraulic pressure as fluid is pumped through the pipeline. On the other hand the foam must be compressible enough to permit the pig 10 to pass through pipeline diameter restrictions caused by wax deposits. Additionally the foam must be of the type that is compatible with crude oil and 15 will not breakdown when immersed therein. For example, polyurethane foam as used in pigs sold by Oll States Industries of Arlington Texas may be used and modified according to the present invention. Also foam density can be varied and is available from Imperial Rubber Company of Nisku, Alberta in 2, 5, 20 and 8 Ibs per cubic foot densities made from buna rubber or neoprene rubber.
The present invention is suitable for pipelines having diameters as large as 36 inches and as small as 2 inches. It will be appreciated however that for smaller pipelines such as 2 inch 25 pipelines smaller electronic packages are required for the onboard data conditioning and storage units.
Reference is made above to a "reasonable seal" between the pig 10 and the pipeline. The better the seal the more closely the pig speed during a run will match the fluid speed. However the 30 present invention also comprehends that there be a fluid flow past (or leak) past the body of the pig. This will allow for a greater control over the speed of the pig 10 and may be desirable to allow any accumulated debris to be pushed ahead of the pig in a fluid plug that is travelling slightly faster than the pig. Of course any 35 such fluid flow past must be controlled to ensure that sufficient pig velocity is maintained and sufficient force is available to push the pig through any pipeline restrictions.
The pressure chamber 44 also contains a source of electric power, such as batteries 60, which supply power to run the sensors, signal conditioning and data acquisition for the duration s of the pig trip.
The data acquisition package 48 and data storage system 49 are preferably capable of running at high precision and high speed to characterize deposit roughness. This data would be typically down loaded onto a computer at a remote location for subsequent data analysis and interpretation, although in some circumstances it might be transferred to a remote computer and interpreted in real-time during the run.
It can now be appreciated that the pig 10 is bidirectional to allow data collection free of disturbance from the pig itself. For 15 instance, by consecutive runs with sensors trailing the first time and then sensors leading the second time, the wax deposition rate data could avoid bias due to the passage of the pig itself. In other words, if the second portion 14 of the pig 10 leads, the sensors' readings will occur before the foam 50 passes over the deposit, 20 making the readings more accurate of the natural state of the wax deposit.
The pig enters the pipeline through a pig launcher, and is recovered at the pipeline outlet via a pig trap in a conventional manner. The velocity of the pig will be determined by the fluid 25 flowrate and the pipe id (accounting for the fluid bypass rate past the pig). Alternatively it may be possible to detect the pipe welds through their magnetic signature, and relate the welds to both location and velocity. Alternatively it may be desirable to use an inertial guidance system or global positioning system (gps) 18 to 30 track pig location.
Once the pig is recovered, the foam shell 50 would be discarded, and the pressure canister 44 opened to access a plug-in connection to download the stored data. The download connection would be an industry standard type such as PCMCIA.
3s Figure 2 shows a theoretical sample of the type of deposit thickness data that the pig would measure. The data tracks the deposit thickness, hardness, and orientation as a function of location within the pipeline if the deposits are asymmetric on the pipewall. Lines A and B for consecutive runs would be used to calculated deposit accumulation rate as shown in Figure 3.
s Figure 4 shows a theoretical schematic of the measured temperature profile within the pipeline. Figure 5 shows the theoretical calculated heat flux based on the rate of change of the temperature. Because wax deposits reduce the heat transfer (i.e.
by preventing convection at the wall), the local heat flux is 10 calculated from measured temperatures. The heat flux can also be related to the temperature gradient at the wall (i.e., across the wax deposit). This data is used to check the hypothesis that the wax deposition rate is correlated with the local heat flux.
By measuring wax deposition rates, as shown in Figure 3, the present invention provides the data necessary to evaluate different wax deposition models. Furthermore, it will be possible according to the present invention to develop more accurate wax deposition models. More sophisticated models can incorporate information about wax deposit roughness, which can have a large 20 impact on the hydraulic efficiency (i.e., pressure drop).
The invention is also useful to determine the impact of operating practices and treatments on wax deposition rates and control. The effect of process parameters (pipeline inlet temperature, flowrate etc.) can be studied and the usefulness of 25 various production chemicals (i.e. wax dispersants, perpend inhibitors, solvents, demulsifiers, flow improvers, and the like) can be determined. Without limiting the types of treatment that can be evaluated there include, solvents, process fluid temperature/flowrate changes, seeding the fluid with wax crystals, 30 pigging and wax chemicals such as dispersants and crystal modifiers. Furthermore the invention is useful to determine the effectiveness of various pipeline design options such as insulated vs uninsulated pipe, pumping speeds temperatures, and overall configurations (bends, junctures and the like).
Additionally, the present invention comprehends capturing a sample of wax from a deposit. In this case, one of the spring -CA 022l8029 l997- lO- lO
leaf arms can carry scraping tool which may be used selectively scrape the wax deposit 38, which scrapings will be recovered for analysis. Most preferably the scraping tool could be actuated (electronically or otherwise) once the pig was in a desired location s so that the wax scrapings could be taken from a known location.
It will be appreciated by those skilled in the art that while reference has been made to specific embodiments of the design various modifications can be made which do not depart from the scope of the instant invention as defined in the appended claims.
10 For example, while reference is made to a foam body, any type of body can be used provided it is flexible enough to pass through pipeline restrictions on the one hand and yet blocks enough flow to motivate the pig on the other hand. Further other configurations of sensor mounts can be used provided that they are positioned to measure properties, including thickness of the overlying wax deposit on the pipeline walls.
Title: Method and Apparatus for Measurement of Wax Deposits FIELD OF THE INVENTION
s This invention relates generally to the field of hydrocarbon recovery and transportation. In particular this invention relates to measuring deposits that form on pipeline equipment, such as pipeline walls during the transportation of hydrocarbons such as waxy crude oils through such equipment.
BACKGROUND OF THE INVENTION
The production of oil and gas is important for both economic and strategic reasons. The recovery of oil or gas from a particular reservoir is determined by the economics of operation. If the revenue is less than the operating costs, then the well will be 15 either shut in (to wait for higher prices, better production technology, etc.) or the well may be plugged with concrete and abandoned. The economics of recovery are related to how much (volume) can be drawn up out of the formation. Pipeline deposits, which constrict flow, can seriously negatively affect such 20 economics. In some environments such as offshore pipelines and tubulars each incident of plugging due to wax deposition can cost millions of dollars. It has been recently reported that 17 such incidents occurred in the Gulf of Mexico during a one year period.
To date there is no reliable technique to predict rates of wax 25 deposition. Lab measurements seldom correlate to measured rates in the field. Allelllpls have been made in the past to assess the factors which control the solubility of the parafffin in crude through analytical measurements and thermodynamic models.
However, wax deposition and plugging of pipelines can be less 30 severe in highly waxy crudes and more severe in less waxy crudes. There are pipelines which carry extremely waxy crude and do not require any wax deposit removal.
A reliable characterization and prediction technique for wax deposition could allow optimization of transporVprocess parameters to minimize capital and operating expenses relating to hydrocarbon recovery. Such a technique could also reduce development and operating costs and allow economic oil recovery from marginal oil pools.
s A key problem limiting prior art techniques is the diffficulty of obtaining wax deposition rate data under actual field conditions.
Typically wax deposition rate data is not available for pipelines.
Operators can only get indirect and imprecise observations such as pipeline displacement volume or friction factor or deposition rate 10 data at the inlet or outlet where access to the pipeline can be obtained. Key information about deposit thickness and roughness cannot be determined. As a result there exists no reliable analytical model to predict wax deposition, because the models being used cannot be checked against field measured data to evaluate the correlation between the effects predicted by the model and the actual field results.
The lack of quantitative field data is a very significant problem. Lab and flow loop wax deposition experiments are of limited value because they cannot be benchmarked against actual 20 field measurements. The lack of field data has prevented the development of accurate wax deposition rate models.
Furthermore, assessment and development of improved control strategies (inhibitors, seeding, etc.) or improved remedial strategies, (pigging, hot water, hot oil, solvents, dispersants, etc.) iS restricted without a means to obtain accurate wax deposition rate measurements in the field.
Thus, there is a need to measure wax deposition rates in operating pipelines for the development of improved wax models, controls and evaluation of remedial technology.
Various pipeline parameters have been measured in the past by use of devices known as "pigs". These are objects which are pushed along by the fluid flow in the conduit and which may carry out certain functions such as scraping wax build-up, or monitoring pipeline integrity through sensors mounted in the pig (the so-called "smart pigs"). However, such pigs have not included sensors capable of sensing information about any wax depositions formed in the pipeline, due to the properties of the wax, which include its soft and sticky consistency, its transparency to conventional sensing signals and other factors.
These smart pig devices consist of, for example an s ultrasonic sensor, and a data transmission module mounted in a pig. The pig is displaced through the pipeline by pumping fluid into the pipeline. Typically these pigs are large and rigid and cannot pass through restrictions. The pipeline must be extremely clean (i.e., no accumulated deposits whatsoever) before the owner of the 10 smart pig would risk running the pig into the pipeline. These pigs are very expensive to operate (50K$ per run) so they are usually only run when required by regulatory agencies.
BRIEF SUMMARY OF THE INVENTION
What is desired is a smart pig that is capable of measuring 15 wax deposition in a field environment. Therefore there is provided according to one aspect of the present invention a smart pig for measuring wax deposits in a pipeline or conduit. The requirements for measuring wax deposition rates are quite different from the typical smart pig application. A pig according to 20 the present invention will be conflgured to have one or more of the following attributes:
1) to be able to pass through a variable (and unknown) pipeline inner diameter (due to accumulated deposit) 2) to measure a soft deposit precisely 3) to be relatively low cost to operate, so multiple runs can be used to measure wax accumulation rates 4) to measure the temperature profile in the pipeline to facilitate the use of thermodynamic calculations in predictive techniques, and 5) measure a pressure differential across the pig to facilitate the integrity of the wax deposit being evaluated.
Another aspect of the present invention is to provide a pig with a flexible body to permit it to fit through partially obstructed pipelines, and which includes sensors to measure various parameters relating to pipeline conditions, the state of the pig itself or wax characteristics and a data storage package to record the data being measured. In a further aspect a telecommunications package is provided to permit data to be transmitted in real time.
Another aspect of the present invention is to provide a s means to measure the thickness of the wax deposits in a pipeline over the entire length of the pipeline so that wax deposit accumulation rates can be determined. While some of the most important data is likely to be that of the deposit thickness, other parameters can also be measured to obtain relevant data 10 according to the present invention. Parameters such as deposit roughness, deposit hardness, deposit composition, suspended waxy solids characteristics, concentricity/eccentricity/orientation of deposits, temperature profiles, heat fluxes are also comprehended by the present invention. This data is useful for bench marking deposition rate calculations with real data to build more accurate deposition models and to provide a more accurate predictive technique.
For instance, one common wax deposition model postulates that wax solids in the oil adhere to the pipe walls. Information 20 about wax deposition profiles at pipeline curves provided by the present invention could help verify/disprove this theory.
Furthermore, wax deposit data produced according to the present invention could be extremely helpful to calibrate pipeline hydraulic models.
Wax deposit data generated according to the present invention will also be useful to examine the effects of various chemical treatments. For instance, a number of chemical products are claimed to reduce deposition rates and/or result in softer deposits. At this time there is no practical way to verify the truth of 30 these claims except by indirect means which are generally unreliable. Thus, wax deposit data will also be useful to optimize the effects of various chemical treatments and facilitate the development of better products.
The apparatus according to the present invention will also 35 be useful to measure the wax deposit accumulation rate for remedial processes such as changes in flow line temperature, flow line configuration and variable suspended solids characteristics (i.e., seeding). In this manner the present invention provides real time field measurements of the effect of various control options on the rate and incidence of wax deposition.
Therefore, there is provided according to one aspect of the present invention an apparatus for measuring wax deposits comprising:
a soft pig which is transported through a pipeline by a fluid flowing in said pipeline, said soft pig being capable of passing through a partially restricted pipeline diameter, a means carried by said soft pig to measure a thickness of the wax deposits in said pipeline.
According to additional aspects of the present invention, the soft pig further includes:
a means to measure and locate an inside wall of said pipeline;
a means to measure a temperature of the fluid adjacent to said soft pig;
a means to locate said pig within said pipeline;
a means to determine a hardness of said wax deposits;
a means to capture samples of said wax deposits;
a means to measure an orientation of said wax deposits;
a means to determine a roughness of said wax deposits;
a means to save said measurement data electronically;
a means to communicate said data to a remote data storage module;
a means to calculate wax deposition rates by comparing total accumulation of wax deposits on successive pig trips;
a means to determine deposit composition and melting~0 point and or dissolution temperature from said samples;
a means to calculate heat fluxes and temperature gradients using the temperature profile data a means for numerical calculation of said wax deposit characteristics using said sensors and probes comprising external~5 computational devices and software Furthermore said apparatus is most preferable small, CA 02218029 1997- lO- lO
inexpensive, robust and portable so that it can be readily transported to remote locations to provide measurements in the oilfield.
s BRIEF DESCRIPTION OF THE DRAWINGS
Reference will now be made, by way of example only, to preferred embodiments of the invention as illustrated in the accompanying drawings and in which:
Figure 1 illustrates a schematic of the invention, a soft 10 pipeline pig to measure deposits on a pipeline wall.
Figure 2 illustrates an example of a theoretical measured deposit thickness on two consecutive runs according to the present invention.
Figure 3 illustrates a calculated wax deposition rate.
Figure 4 illustrates a measured temperature profile in the pipeline.
Figure 5 illustrates a calculated heat flux and a calculated temperature gradient at the pipeline wall.
DETAILED DESCRIPTION OF THE PREFERRED
This patent applies to the measurement and prediction of waxy crude properties. As waxy crudes cool down or lose volatiles, during transport from the reservoir to the refinery, parafffin wax will precipitate. This precipitation may occur on the pipeline 25 inner walls or at other locations in the transportation system such as on pumps, rods, valves and the like. The precipitated parafffins cause numerous problems. For example they cause flow obstructions and even plug off pipelines; they cause poor pumpability due to high viscosity and cause a difficulty breaking 30 water/oil emulsions.
Reference is made in this invention to measurement of "deposits" in pipelines. While the primary deposits being measured are wax deposits, it will be understood that other deposits can also be measured such as scales and even coated 35 liners and the like, for thickness and other properties. Thus, the -present invention provides data from inside pipelines about flow restriction, and in particular waxy flow restrictions.
The present invention provides a quantitative approach to understand the processes affecting the waxy crude characteristics.
5 This invention is directed to the measurement of wax deposits and the use of this measured information in the understanding of the dynamics of wax deposition processes in pipelines. The term pipeline and conduit in this application will be understood to mean any closed tube through which a fluid may be pumped and which 10 therefore may carry a pig through its bore. The terms pipeline, conduit and flow line mean any pipe or conduit through which fluids flow and includes tubing strings, casings, above or below grade pipes, underwater pipes, inter-rig pipes or pipelines, hoses, and other fluid passage conduits used in the transportation of hydrocarbons.
Turning to Figure 1, there is shown an intelligent soft pig 10 according to the present invention. The pig 10 is used to characterize and measure wax deposits on the walls of pipelines and flow lines as more fully described below.
The pig 10 has a two-part body including a first portion 12 and a second portion 14. Carried in the pig 10 are the following components, sensors to detect deposit thickness and hardness 16, sensor(s) to detect pig location and orientation (up/down) 18, sensors to detect fluid temperature 20, sensors to detect pipeline inner diameter (ID) 22, and sensors 24 to detect a pressure drop across the pig 10. Deposit thickness, hardness, fluid temperature pipeline ID and pressure sensors are immersed in the pipeline fluid, as shown, while the location and orientation sensors are located inside a pressure capsule 44 located within the first body portion 12.
As shown in the drawing the pipeline inner diameter sensor 22 may take the form of a displacement sensor, such as manufactured by Kaman Instrumentation of Colorado Springs Colorado. The measurements of the inner diameter sensor 22 can 35 be related to the measurements of the thickness sensor 16 to determine the inner diameter of the pipeline The second body portion 14 consists of a sensor mounting structure 30 which in the preferred embodiment is mounted on a springleaf 32. The springleaf 32 is comprised of three spring arms 34a 34b and 34c as shown. It will be appreciated that more or s fewer spring arms can be used and the number desired will depend on the number of sensors used, the degree of redundancy designed into the device and the degree of accuracy required in locating the sensors about the inner circumference of the pipeline being measured. More specifically more sensors around the inner 10 circumference will provide more accurate information about the deposits on the inner circumference about the inner pipeline wall.
However it is believed that three sensors will provide sufficient information.
Turning to the arm 34a, it will now be more particularly described. While the description is in reference to spring arm 34a it is generally applicable also to spring arms 34b and 34c. The spring arm 34a is of a bowed configuration as shown and includes a wax thickness sensor 16 at its outermost point. The natural or rest position the arm 34a is at a position spaced outwardly of the 20 inner diameter of the pipeline 36. The spring arm 34a is compressed to be inserted into the pipeline 36 and therefore the spring arm 34a is urged into contact with the inside surface of the pipeline 36. In this way the spring arm 34a is used to position the wax deposit sensors 16 against the pipeline ID, or against any wax 25 deposit 38 which is present. The tension in the spring 34a is adjusted to vary the penetration of the sensors 16 into the wax deposit 38 and thus obtain data on wax deposit hardness.
Alternatively the sensors 16 may be mounted in sensor mounts 30 having smaller or larger footprints to vary penetration based on 30 deposit 38 hardness and also resolve smaller details of deposit 38 roughness. The wax deposit thickness sensors 16 preferably use either an inductive bridge or a Colpits oscillator as a means to detect the proximity to the steel substrate (i.e. pipewall 36) such as those manufactured by Kaman Instrumentation of Colorado 3s Springs, Colorado. It will be appreciated by those skilled in the art that other types of sensors might also be used, provided that they CA 022l8029 l997- lO- lO
are able to detect the separation distance between a fixed point and the pipeline wall, to obtain a measure of the wax deposit 38 thickness.
It can now be appreciated that with three spring arms 34 the 5 deposit 38 thickness will be tracked at three points around the inner circumference of the pipeline 36 generally separated by 120 degrees. If more data points are required, for example because the deposit thickness varies about the circumference, then more arms and more sensors can be used.
The electronic signals from the outside sensors 16, 20 and 22 are routed via cables 40 through a electrical feedthrough pressure seal 42 into a clean dry pressure chamber 44 which holds the signal conditioning electronics 46 and the data acquisition electronics 48. Some sensors may require the cables 40 be in the form of coaxial wires while others might require twisted pairs, but both are comprehended by the present invention.
Further sensors (up/down orientation, inertial/gps locator) 18 would also be placed inside the clean pressure chamber 44.
Signal conditioning unit 46 include filters, and/or current to 20 voltage conversion prior to the data acquisition 48, as well as shielding and ground connections. The data acquisition system 48 is most preferably a speed - high precision (i.e. 16 bit system) electronic instrument with adequate memory capacity to collect the sensed information. Averaging/smoothing of the data could be 25 achieved via software or hardware means either in the data acquisition package 48 or in a remote station where the sensed data is down loaded. Data processing would also be used to filter out recognizable magnetic anomalies such as pipe welds.
The pressure chamber 44 is encapsulated in a soft foamed 30 rubber or like material 50, having a low durometer rating. The pressure chamber 44 is preferably held within the foam 50 by flexible oversize rubber caps 52 screwed or bolted to the ends of the pressure chamber by fasteners 54. It will be appreciated that other ways of attaching the foam 50 to the pressure chamber 44 3s could also be used.
Most preferably the foam 50 will be removably attached to the pressure chamber 44 to form the pig 10. In this manner, the foam 50 would be disposable and could be discarded after each run. The same pressure chamber 44 and sensors and electronics could then be inserted into different sized foam tubes 50 to readily s adapt the pig 10 to different pipeline diameters.
It will be appreciated that the use of a foam body 50 permits the pig 10 to pass through a pipeline of varying diameter due to, for example, wax deposition. The foam must be stiff enough, on the one hand, to form a reasonable seal with the pipeline wall. In 10 this way the pig 10 will be pushed along by hydraulic pressure as fluid is pumped through the pipeline. On the other hand the foam must be compressible enough to permit the pig 10 to pass through pipeline diameter restrictions caused by wax deposits. Additionally the foam must be of the type that is compatible with crude oil and 15 will not breakdown when immersed therein. For example, polyurethane foam as used in pigs sold by Oll States Industries of Arlington Texas may be used and modified according to the present invention. Also foam density can be varied and is available from Imperial Rubber Company of Nisku, Alberta in 2, 5, 20 and 8 Ibs per cubic foot densities made from buna rubber or neoprene rubber.
The present invention is suitable for pipelines having diameters as large as 36 inches and as small as 2 inches. It will be appreciated however that for smaller pipelines such as 2 inch 25 pipelines smaller electronic packages are required for the onboard data conditioning and storage units.
Reference is made above to a "reasonable seal" between the pig 10 and the pipeline. The better the seal the more closely the pig speed during a run will match the fluid speed. However the 30 present invention also comprehends that there be a fluid flow past (or leak) past the body of the pig. This will allow for a greater control over the speed of the pig 10 and may be desirable to allow any accumulated debris to be pushed ahead of the pig in a fluid plug that is travelling slightly faster than the pig. Of course any 35 such fluid flow past must be controlled to ensure that sufficient pig velocity is maintained and sufficient force is available to push the pig through any pipeline restrictions.
The pressure chamber 44 also contains a source of electric power, such as batteries 60, which supply power to run the sensors, signal conditioning and data acquisition for the duration s of the pig trip.
The data acquisition package 48 and data storage system 49 are preferably capable of running at high precision and high speed to characterize deposit roughness. This data would be typically down loaded onto a computer at a remote location for subsequent data analysis and interpretation, although in some circumstances it might be transferred to a remote computer and interpreted in real-time during the run.
It can now be appreciated that the pig 10 is bidirectional to allow data collection free of disturbance from the pig itself. For 15 instance, by consecutive runs with sensors trailing the first time and then sensors leading the second time, the wax deposition rate data could avoid bias due to the passage of the pig itself. In other words, if the second portion 14 of the pig 10 leads, the sensors' readings will occur before the foam 50 passes over the deposit, 20 making the readings more accurate of the natural state of the wax deposit.
The pig enters the pipeline through a pig launcher, and is recovered at the pipeline outlet via a pig trap in a conventional manner. The velocity of the pig will be determined by the fluid 25 flowrate and the pipe id (accounting for the fluid bypass rate past the pig). Alternatively it may be possible to detect the pipe welds through their magnetic signature, and relate the welds to both location and velocity. Alternatively it may be desirable to use an inertial guidance system or global positioning system (gps) 18 to 30 track pig location.
Once the pig is recovered, the foam shell 50 would be discarded, and the pressure canister 44 opened to access a plug-in connection to download the stored data. The download connection would be an industry standard type such as PCMCIA.
3s Figure 2 shows a theoretical sample of the type of deposit thickness data that the pig would measure. The data tracks the deposit thickness, hardness, and orientation as a function of location within the pipeline if the deposits are asymmetric on the pipewall. Lines A and B for consecutive runs would be used to calculated deposit accumulation rate as shown in Figure 3.
s Figure 4 shows a theoretical schematic of the measured temperature profile within the pipeline. Figure 5 shows the theoretical calculated heat flux based on the rate of change of the temperature. Because wax deposits reduce the heat transfer (i.e.
by preventing convection at the wall), the local heat flux is 10 calculated from measured temperatures. The heat flux can also be related to the temperature gradient at the wall (i.e., across the wax deposit). This data is used to check the hypothesis that the wax deposition rate is correlated with the local heat flux.
By measuring wax deposition rates, as shown in Figure 3, the present invention provides the data necessary to evaluate different wax deposition models. Furthermore, it will be possible according to the present invention to develop more accurate wax deposition models. More sophisticated models can incorporate information about wax deposit roughness, which can have a large 20 impact on the hydraulic efficiency (i.e., pressure drop).
The invention is also useful to determine the impact of operating practices and treatments on wax deposition rates and control. The effect of process parameters (pipeline inlet temperature, flowrate etc.) can be studied and the usefulness of 25 various production chemicals (i.e. wax dispersants, perpend inhibitors, solvents, demulsifiers, flow improvers, and the like) can be determined. Without limiting the types of treatment that can be evaluated there include, solvents, process fluid temperature/flowrate changes, seeding the fluid with wax crystals, 30 pigging and wax chemicals such as dispersants and crystal modifiers. Furthermore the invention is useful to determine the effectiveness of various pipeline design options such as insulated vs uninsulated pipe, pumping speeds temperatures, and overall configurations (bends, junctures and the like).
Additionally, the present invention comprehends capturing a sample of wax from a deposit. In this case, one of the spring -CA 022l8029 l997- lO- lO
leaf arms can carry scraping tool which may be used selectively scrape the wax deposit 38, which scrapings will be recovered for analysis. Most preferably the scraping tool could be actuated (electronically or otherwise) once the pig was in a desired location s so that the wax scrapings could be taken from a known location.
It will be appreciated by those skilled in the art that while reference has been made to specific embodiments of the design various modifications can be made which do not depart from the scope of the instant invention as defined in the appended claims.
10 For example, while reference is made to a foam body, any type of body can be used provided it is flexible enough to pass through pipeline restrictions on the one hand and yet blocks enough flow to motivate the pig on the other hand. Further other configurations of sensor mounts can be used provided that they are positioned to measure properties, including thickness of the overlying wax deposit on the pipeline walls.
Claims (24)
1. An apparatus for measuring deposits in pipelines comprising:
a fluid immersible body being sized and shaped to be insertable into said pipeline to at least partially block a flow of fluid past said body portion in said pipeline;
sensing means connected to said body portion to measure deposits in said pipeline; and data storage means associated with said sensing means to record said measurements.
a fluid immersible body being sized and shaped to be insertable into said pipeline to at least partially block a flow of fluid past said body portion in said pipeline;
sensing means connected to said body portion to measure deposits in said pipeline; and data storage means associated with said sensing means to record said measurements.
2. An apparatus as claimed in claim 1 wherein said sensing means includes a deposit thickness sensor for measuring the thickness of a deposit in said pipeline at least one location.
3. An apparatus as claimed in claim 2 wherein said body portion is at least partially compressible to permit said body portion to pass through a length of pipeline having a restricted inner diameter for at least some of said length due to the presence of said deposits being measured in said pipeline.
4. An apparatus as claimed in claim 3 wherein said sensing means further includes a pressure sensing means to measure a pressure in said pipeline.
5. An apparatus as claimed in claim 4 wherein said pressure sensing means includes a first pressure sensor and a second pressure sensor to measure pressure on an upstream and a downstream side of said body to permit a pressure drop across said body to be measured.
6. An apparatus as claimed in claim 2 further including position sensors to relate deposit measurements to the position within the pipeline where such measurements were made.
7. An apparatus as claimed in claim 5 wherein said position sensors further relate deposit measurements to an orientation within the pipeline.
8. An apparatus as claimed in claim 2, further including temperature sensors measure fluid temperature within the pipeline.
9. An apparatus as claimed in claim 2, said apparatus further including roughness sensors to measure deposit roughness.
10. An apparatus as claimed in claim 2, said apparatus having hardness sensors to measure deposit hardness.
11. An apparatus as claimed in claims 2 wherein said data storage means is carried in said body portion.
12. An apparatus as claimed in claim 11 wherein said data storage means includes data port means to download stored data to a remote central processing unit for subsequent manipulation of said measurements.
13. An apparatus as claimed in claim 2 wherein said deposit thickness sensors are urged into engagement with said deposits.
14. An apparatus having a plurality of deposit thickness sensors urged into engagement with an inner surface of said deposits.
15. An apparatus as claimed in claim 2 wherein said deposit thickness sensors are mounted on a spring means which urges the sensor into engagement with an inner surface of said deposits.
16. An apparatus as claimed in claim 2 wherein said hardness sensor measure a relative deflection of said deposit thickness sensor under differing loads.
17. An apparatus as claimed in claim 1 wherein said body includes a foam portion and a sealed pressure chamber.
18. An apparatus as claimed in claim 17 wherein said pressure chamber further includes a signal conditioning means to condition signals received from said sensing means.
19. An apparatus as claimed in claim 18 wherein said pressure chamber further includes a power source.
20. An apparatus as claimed in claim 1 wherein said deposit being measured is wax.
21. A method of measuring the effect of wax control treatments in pipelines comprising:
measuring a wax deposit thickness before and after the treatment.
measuring a wax deposit thickness before and after the treatment.
22. A method of predicting wax deposit characteristics in pipelines comprising:
using a model to predict wax deposition in a given pipeline;
measuring actual wax deposition predicted by the model in said given pipeline;
comparing the measured results with the predicted results;
and revising the model to permit a closer correlation to said measured results.
using a model to predict wax deposition in a given pipeline;
measuring actual wax deposition predicted by the model in said given pipeline;
comparing the measured results with the predicted results;
and revising the model to permit a closer correlation to said measured results.
23. A method of measuring wax deposition rates in pipelines comprising:
passing an apparatus for measuring deposit thickness as claimed in claim 1 through the pipeline on a first occasion;
passing the apparatus for measuring deposit thickness as claimed in claim 1 through the pipeline on a second occasion; and calculating the rate of change of deposit thickness over time.
passing an apparatus for measuring deposit thickness as claimed in claim 1 through the pipeline on a first occasion;
passing the apparatus for measuring deposit thickness as claimed in claim 1 through the pipeline on a second occasion; and calculating the rate of change of deposit thickness over time.
24. A method of measuring deposits in pipelines comprising:
placing a sensing device in the pipeline;
passing the sensing device through the pipeline;
measuring the deposits in the pipeline and recording the measurements of said deposits in an electronic format.
placing a sensing device in the pipeline;
passing the sensing device through the pipeline;
measuring the deposits in the pipeline and recording the measurements of said deposits in an electronic format.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2218029 CA2218029A1 (en) | 1997-10-10 | 1997-10-10 | Method and apparatus for measuring deposits in pipelines |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA 2218029 CA2218029A1 (en) | 1997-10-10 | 1997-10-10 | Method and apparatus for measuring deposits in pipelines |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2218029A1 true CA2218029A1 (en) | 1999-04-10 |
Family
ID=4161613
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2218029 Abandoned CA2218029A1 (en) | 1997-10-10 | 1997-10-10 | Method and apparatus for measuring deposits in pipelines |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA2218029A1 (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6931952B2 (en) | 2000-12-22 | 2005-08-23 | Canadian Mining Industry Research Organization | Device for in-line measurement of properties of fluid flows in pipeline systems |
| CN103116015A (en) * | 2013-01-28 | 2013-05-22 | 中国石油大学(华东) | Wax deposition rate measuring device for crude oil |
| CN110208500A (en) * | 2019-07-01 | 2019-09-06 | 中国石油化工股份有限公司 | A kind of crude oil pipeline wax deposit pigging analogue experiment method |
| CN112000916A (en) * | 2020-09-01 | 2020-11-27 | 西安石油大学 | Oil pipeline axial wax deposition distribution rule judgment method based on mass flow change |
| CN113582394A (en) * | 2021-08-10 | 2021-11-02 | 上海海姆环境工程有限公司 | Pretreatment method and device for oil-containing wastewater of ship |
| US20220003638A1 (en) * | 2020-07-01 | 2022-01-06 | Saudi Arabian Oil Company | In-line fluid and solid sampling within flowlines |
| CN114278873A (en) * | 2021-12-23 | 2022-04-05 | 天津大学 | Remote monitoring method for pipeline fault |
| CN116067310A (en) * | 2023-04-06 | 2023-05-05 | 国家石油天然气管网集团有限公司 | Oil and gas pipeline inner diameter detection device and method |
| US11865928B2 (en) | 2021-11-24 | 2024-01-09 | Saudi Arabian Oil Company | Generating power with a conduit inspection tool |
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1997
- 1997-10-10 CA CA 2218029 patent/CA2218029A1/en not_active Abandoned
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6931952B2 (en) | 2000-12-22 | 2005-08-23 | Canadian Mining Industry Research Organization | Device for in-line measurement of properties of fluid flows in pipeline systems |
| CN103116015A (en) * | 2013-01-28 | 2013-05-22 | 中国石油大学(华东) | Wax deposition rate measuring device for crude oil |
| CN103116015B (en) * | 2013-01-28 | 2014-12-17 | 中国石油大学(华东) | Wax deposition rate measuring device for crude oil |
| CN110208500A (en) * | 2019-07-01 | 2019-09-06 | 中国石油化工股份有限公司 | A kind of crude oil pipeline wax deposit pigging analogue experiment method |
| CN110208500B (en) * | 2019-07-01 | 2023-11-14 | 中国石油化工股份有限公司 | Crude oil pipeline wax sediment pipe cleaning simulation experiment method |
| US20220003638A1 (en) * | 2020-07-01 | 2022-01-06 | Saudi Arabian Oil Company | In-line fluid and solid sampling within flowlines |
| US11788934B2 (en) * | 2020-07-01 | 2023-10-17 | Saudi Arabian Oil Company | In-line fluid and solid sampling within flowlines |
| CN112000916A (en) * | 2020-09-01 | 2020-11-27 | 西安石油大学 | Oil pipeline axial wax deposition distribution rule judgment method based on mass flow change |
| CN113582394A (en) * | 2021-08-10 | 2021-11-02 | 上海海姆环境工程有限公司 | Pretreatment method and device for oil-containing wastewater of ship |
| CN113582394B (en) * | 2021-08-10 | 2023-09-12 | 上海海姆环境工程有限公司 | Pretreatment method and device for oil-containing wastewater of ship |
| US11865928B2 (en) | 2021-11-24 | 2024-01-09 | Saudi Arabian Oil Company | Generating power with a conduit inspection tool |
| CN114278873A (en) * | 2021-12-23 | 2022-04-05 | 天津大学 | Remote monitoring method for pipeline fault |
| CN114278873B (en) * | 2021-12-23 | 2022-09-16 | 天津大学 | Remote monitoring method for pipeline fault |
| CN116067310A (en) * | 2023-04-06 | 2023-05-05 | 国家石油天然气管网集团有限公司 | Oil and gas pipeline inner diameter detection device and method |
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