Patent Description:
Inorganic scale deposition has been a persistent problem in many oil and gas production systems. Scale deposits can restrict hydrocarbon flow, damage equipment, induce localized corrosion, and interfere with oil-water separation. For example, calcium carbonate scale deposition in surface flowlines is a significant issue for many oil wells and has been known to interrupt or stop oil production. In some cases, wells have been in a shut-in state due to heavy calcium carbonate scale in flowlines, leading to enormous economic losses. Many approaches have been deployed to control scale formation.

<CIT> describes a water softening device that includes a filter which is configured to decrease hardness of a first stream of raw water to produce a second stream of water with decreased hardness. The device includes a first sensor for measuring an electrical property of the first stream and a second sensor for measuring an electrical property of the second stream. The ratio of the measured properties can be used as an indicator to estimate the exhaustion state of the filter.

<CIT> describes a kit for retrofitting an unregulated water softening system with a fully automatic intersection control. The kit includes a first module, in particular a soft water module, with an inlet, a drain and a first flow meter for flowing water. The kit includes a second module, in particular a hard water module, with an inlet, a drain, a water hardness sensor and a second flow meter for water flowing through and a control valve with a motorized actuator for adjusting the water flow of the flowing water. The kit includes a control unit for evaluating the data of the two flowmeters and the water hardness sensor and for controlling the motorized adjusting device. Water flows through the water softener over a set on the control unit programmed blend water hardness.

<CIT> describes a method for monitoring a water treatment system, in particular a water-circuit filling system, with which water is charged into a water circuit, in particular a heating or cooling circuit. The water-treatment system includes a vessel that has water treatment elements. The exhaustion state of the water-treatment elements is monitored by a measuring unit. In the monitoring unit, the following parameters are determined: an amount of water M flowing through the vessel, a first, instantaneous conductivity LI of untreated water, a second, instantaneous conductivity L2 of treated water or of partially treated water after a blending. The exhaustion of the water-treatment elements is signaled when an instantaneous residual capacity RK of the water treatment elements determined from the amount of water M and one or more associated first conductivities LI falls below a first limiting value GW1, and in that, likewise, an exhaustion of the water-treatment elements is signaled when a deviation of the second instantaneous conductivity L2 exceeds a second limiting value GW2 by a predetermined theoretical value SW. Accordingly, a changing raw water quality can automatically be recognized and the used state of the water-treatment elements can be monitored with high reliability.

<CIT> describes a method of recovering oil from an oil-bearing formation including recovering an oil-water mixture from the oil-bearing formation and separating produced water from the oil water mixture. The produced water includes phosphonate anti-sealant compounds. An oxidant is mixed with the produced water to deactivate the phosphonate anti-scalant compounds, thereby permitting dissolved solids in the produced water to precipitate. After deactivating the phosphonate anti-scalant compounds, the produced water is directed into a ceramic membrane which filters the produced water, producing a permeate stream and a retentate stream having suspended solids and precipitants therein.

This disclosure describes systems and methods that are used in treating fluids in oilfield facilities. These systems and methods are used to treat fluids to inhibit scale in surface components of oilfield facilities. In another example, these systems and methods could be used to address additional production chemistry issues such as corrosion and emulsion.

In contrast to the solid scale inhibitor deployment techniques that place scale inhibitors in the rathole at the bottom of a well or mixed with proppant or sand for well completion, these systems and methods include adding a solid scale inhibitor into a vessel in line with a surface pipeline. In a representative example, a vessel loaded with solid-state inhibitor is connected to a produced fluid pipeline from an oil or gas well near wellhead and some of the produced water is diverted into the vessel. The diverted water in the holding rank releases active scale inhibition compounds from the solid inhibitor product. Water from the vessel with the active scale inhibition compounds is returned to the pipeline, which results in the downstream pipeline being treated with the inhibitor to prevent scale deposition. The concentration of scale inhibitor in the main stream can be controlled by adjusting the flow rate of the side stream. In addition, and in contrast to existing methods of continuously injecting a liquid scale inhibitor, this approach does not require a metering injection pump, which significantly simplifies the treatment procedure, reduces maintenance cost, and improves treatment reliability.

Some systems and methods use a solid scale inhibitor material at a surface facility to introduce active scale inhibition compounds into pipelines carrying fluids produced from a wellbore by diverting a side stream of the produced water into a vessel holding the solid scale inhibitor material and returning the diverted flow into the pipeline. The diverted produced water enters the container and causes a release of active scale inhibition compounds from solid inhibitor into the produced water. The diverted produced water, now containing the active scale inhibition compounds, merges with the produced fluid in the pipeline. The concentration of scale inhibitor in the mixed stream can be adjusted to reduce or prevent scale buildup in surface components of the system by adjusting the flow rate of the diverted water.

Some methods of inhibiting scale in an oilfield facility include diverting a side stream of produced water from a pipeline into a vessel containing a solid scale inhibitor material to release of active scale inhibition compounds from the solid scale inhibitor material into the diverted produced water, returning the diverted produced fluid containing the active scale inhibition compounds into the pipeline, and adjusting a flow rate of the diverted side stream of the produced water to change a level of active scale inhibition compounds in the flow of produced water in the pipeline. The active scale inhibition compounds include one or more of: phosphonates, phosphonate esters, and polymeric compounds.

Embodiments can include one or more of the following features.

In some embodiments, methods include measuring the level of the scale inhibition compounds in the produced water in the pipeline downstream of the vessel. In some embodiments, methods include replacing the sold scale inhibitor material when adjusting the flow rate of the diverted side stream fails to maintain the level of active scale inhibition compounds in the flow of produced water in the pipeline at or above a threshold level. In some embodiments, methods include setting the threshold level based at least in part on the length of flowlines through the oilfield facility.

In some embodiments, adjusting the flow rate of the diverted side stream includes controlling a bypass valve upstream of the vessel.

According to the invention, adjusting the flow rate of the diverted side stream includes controlling a main valve disposed in the pipeline between a location in the pipeline where the side stream is diverted and a location in the pipeline where the side stream is returned.

In some embodiments, adjusting the flow rate of the diverted side stream includes controlling a return valve downstream of the vessel.

In some embodiments, the pipeline is a surface pipeline and the flow of produced water is produced from a well of the oilfield facility.

In some embodiments, the solid scale inhibitor material is in the form of capsules and the active scale inhibition compounds are enclosed by permeable or semi-permeable materials.

In some embodiments, the solid scale inhibitor materials include a porous solid material with high surface areas with the active scale inhibition compounds adsorbed into the porous solid material. In some embodiments, the porous solid material includes one or more of: activated carbon, zeolite, cluster of nanoparticles and carbon nanotubes, and microporous thin films.

In some embodiments, methods include continuously diverting the side stream of the produced water from the pipeline into the vessel, and continuously merging the diverted produced fluid containing the active fluid treatment agent back into in the flow of produced water in the pipeline.

Some scale prevention systems for use in an oilfield facility include a pipeline carrying a flow of produced water from a wellhead, a vessel containing a solid scale inhibitor material configured to release active scale inhibition compounds into produced water in the vessel, a bypass line providing a fluid connection between the pipeline and an inlet of the vessel, a return line providing a fluid connection between an outlet of the vessel and the pipeline, and a sensor downstream of a location at which the return line connects to the pipeline, the sensor operable to measure a level of the active scale inhibition compounds in produced water in the pipeline. The active scale inhibition compounds include one or more of: phosphonates, phosphonate esters, and polymeric compounds.

Embodiments of these systems can include one or more of the following features.

In some embodiments, systems include a flowmeter disposed to measure a flowrate in the bypass line or the return line.

Systems according to the invention include a main valve in the pipeline positioned between a location at which the bypass line connects to the pipeline and a location at which the return line connects to the pipeline.

Systems according to the invention include a controller operatively coupled to the main valve and to the sensor, where the controller is configured to adjust a flow rate of the produced water entering the vessel based at least in part on a signal received from the sensor.

In some embodiments, systems include a bypass valve in the bypass line. In some embodiments, systems include a return valve in the return line.

In some cases, these systems and methods can significantly simplify the treatment process, reduce maintenance costs, and provide efficient and reliable treatment results. In particular, these systems and methods can provide continuous injection of scale inhibitor to protect against scale deposition in surface components of oilfield facilities such as, for example, oil field flowlines. This approach can provide long-term, more consistent protection than intermittent approaches such as existing squeeze treatments.

In addition to being more effective than existing oilfield scale control solutions, these systems and methods are anticipated to reduce operation costs due to a simplified technique and lower maintenance requirement. In some cases, the ongoing controlled application scale inhibitors lowers overall inhibitor requirements relative to approaches that apply pulses of inhibitor to the oilfield facilities. This scale treatment program is easy to adjust in response to changing conditions and fluid being treated. The control provided by this approach provides a an advantage over approaches, such as placement of solid inhibitor in rathole at the bottom of well below tubing, in which there is no control on interaction of produced fluid with solid inhibitor and the resulting concentration of active scale inhibitor released into the produced water. This approach also avoids the downhole restrictions in fluid flow and associated impacts on production that can result from approaches that place a container with treatment chemicals in a downhole tubular. By applying the scale inhibitor at the surface downstream of the well, this approach can also reduce or eliminate the potential of formation damage induced by squeeze treatment.

The system and methods described can be effective in maintaining effective levels of treatment chemicals in surface installations. This is important, for example, because scale formation is more severe at the surface than downhole due to changes in temperature and pressure. The reduction in pressure as produced fluid flows from the subsurface to the surface decreases scaling mineral solubility and, therefore, increases the scaling potential for pH sensitive scale types, such as carbonate and sulfide.

The systems and methods of this disclosure can provide controllable levels of scale inhibitors in surface installations in contrast to squeeze treatments and downhole solid inhibitor batch treatments are often only designed to provide scale inhibition for downhole equipment, which typically have less scaling problem due to relatively low scaling tendency and a short residence time of the produced water. Moreover, the scale inhibitor concentrations in the produced water in the downhole-focused treatments are insufficient to prevent scale formation when the produced water travels to surface. Increased scaling tendency, coupled with longer residence life, especially for producers with long flowlines, demands higher scale inhibitor concentration to stop scale formation at surface.

These systems and methods can also protect formation productivity by introducing treatment chemicals after produced fluids leave a well. In contrast, scale inhibitor squeeze treatment systems rely on pumping an inhibitor product into a reservoir under high pressures and part of the pumped inhibitor produce is retained by reservoir rocks--by either an adsorption or precipitation processes. During production, the retained inhibitors are gradually released into the produced water and scale formation is be prevented if the released scale inhibitor concentration is high enough. However, there is no control over the inhibitor concentration and frequent repeated treatments are often required. Moreover, this treatment can cause formation damage, which reduces hydrocarbon recovery.

The systems and methods of this disclosure can more effectively provide protection than approaches in which solid-state scale inhibitors used for downhole scale control have high strength solid inhibitor particles are incorporated with the fracturing proppants. However, because of the limited amount of inhibitor added, these downhole methods only provide temporary scale protection.

This specification describes systems and methods of treating fluids produced from a well by diverting a side stream of produced fluids into a container holding solid treatment material. The diverted fluids release treatment compounds from solid treatment material before being returned to the main stream of the produced fluids. For example, these systems and methods can be used to control scaling deposition in oil well surface flowlines and trunklines. In this approach, a side stream of produced water is diverted into a container holding solid scale inhibitor material. The diverted produced water enters the container and releases active scale inhibition components from solid inhibitor. The diverted produced water, now containing active scale inhibition components, merges with the produced fluid in the pipeline. By adjusting the flow rate of the diverted water, scale inhibitor concentration in the mixed stream is adjusted to reduce or prevent scale buildup in surface components of the system.

This approach can reduce or eliminate production losses due to scale deposition. The solid-state scale inhibitor can provide a continuous supply of scale control ingredient without using an injection pump. In contrast to pulsed squeeze treatments, this approach can provide long-term ongoing protection to equipment. The described systems and methods can be used in addition to the squeeze treatment to prevent scale formation in surface flowlines and facilities as squeeze treatment is mainly used to control scale in subterranean formation. In addition, this approach is anticipated to reduce operation costs relative to systems and methods that rely on continuous injection of treatment compounds.

These systems and methods can also be used to introduce additional types of treatment agents such as, for example, corrosion inhibitors, paraffin inhibitors, asphaltene inhibitors, oxygen scavengers, biocides, gas hydrate inhibitors, salt inhibitors, foaming agent, emulsion breakers and surfactants, into a oilfield facility. Integration of different oilfield chemical treatments into a single process can be performed by adding different treatment chemicals in a solid form in the same vessel.

<FIG> shows an oilfield facility <NUM> with a well <NUM> extending into a subterranean formation <NUM> from a wellhead <NUM>. A pipeline <NUM> extends between the wellhead and downstream components <NUM> (for example, trunklines, oil-water separators, and water knockout units) of the oilfield facility <NUM> to transport fluids (for example, produced water) produced from the well to the downstream components <NUM>. A treatment system <NUM> is attached to the flowline <NUM>. The treatment system <NUM> is a scale inhibitor system and is described with respect to scale inhibitors. As previously noted, some treatment systems are used to supply other treatment chemicals in addition to scale inhibitors.

The treatment system <NUM> includes a vessel <NUM>, a bypass line <NUM> providing a fluid connection between the pipeline <NUM> and an inlet <NUM> of the vessel <NUM>; and a return line <NUM> providing a fluid connection between an outlet <NUM> of the vessel <NUM> and the pipeline <NUM>. The return line <NUM> directs the return flow <NUM> of produced water (containing the active scale inhibition compounds) to the pipeline <NUM> at a location downstream of the connection of the bypass line <NUM>.

In the treatment system <NUM>, the vessel <NUM> is a tank. Some treatment systems use non-tank vessels such as, for example, chemical storage drums or holding ponds. A solid scale inhibitor material <NUM> is disposed in the vessel <NUM> to release active scale inhibition compounds and optionally other treatment chemicals into fluids flowing through the vessel <NUM>.

In operation, fluid flowing from the wellhead <NUM> flows through the pipeline <NUM> as indicated by arrow <NUM>. A portion of the fluid is diverted through the bypass line <NUM> as indicated by arrow <NUM> while the rest of the fluid continues down the pipeline <NUM> as indicated by arrow <NUM>. The diverted fluid flows through the vessel <NUM>. Contact between the diverted fluid and the solid-state treatment chemicals <NUM> in the vessel <NUM> releases a portion of the treatment chemicals into the diverted flow. The diverted fluid and released treatment chemicals flow through the return line <NUM> as indicated by arrow <NUM> to merge with the fluid that was not diverted to form a treated fluid stream that flows down the pipeline <NUM> as indicated by arrow <NUM>. By mixing the remaining flow <NUM> with the returned flow <NUM>, the concentration of treatment chemicals <NUM> (for example, active scale inhibition compounds) in the treated stream <NUM> to prevent scale formation in downstream is controlled by the flowrate and concentration of the treatment chemicals <NUM> of the return flow <NUM>.

While the oilfield facility <NUM> is described as a surface facility having a surface pipeline <NUM>, these systems and methods can also be applied in other settings such as, for example, on an offshore platform or in a facility with underground pipelines.

<FIG> is a more detailed schematic of the treatment system <NUM> showing a control system <NUM> that is configured to control the flowrate and concentration of the active scale inhibition compounds <NUM> of the return flow <NUM>. The control system <NUM> is operatively coupled to a main valve <NUM> in the pipeline <NUM> between the bypass line <NUM> and the return line <NUM>. The treatment system <NUM> also includes a bypass valve <NUM> in the bypass line <NUM> and a return valve <NUM> in the return line <NUM>. Both the bypass valve <NUM> and the return valve <NUM> are also operatively connected to the controller <NUM>. The control system <NUM> is also in communication with flowmeters <NUM>, <NUM> and sensors <NUM>, <NUM>, <NUM>. The sensor <NUM> measures chemical concentrations in the vessel <NUM>, the sensor <NUM> measures chemical concentrations in the return line <NUM>, and the sensor <NUM> measures chemical concentrations in the pipeline <NUM> downstream of a location at which the return line <NUM> connects to the pipeline <NUM>. For example, the sensor <NUM> can be operable to measure a level of the active scale inhibition compounds in produced water in the pipeline <NUM>. In this situation, the controller can be operatively coupled to the main valve <NUM> and to the sensor <NUM> and configured to adjust a flow rate of the produced water entering the vessel <NUM> based at least in part on a signal received from the sensor <NUM>.

The control system of the treatment system <NUM> is configured to provide sufficient inhibitor concentration in a simple and cost effective way by using the solid scale inhibitors in the vessel <NUM> and controlling the flowrate of the bypass flow <NUM>. In operation, the control system <NUM> controls the treatment system <NUM> to provide the scale inhibitor compounds <NUM> in a concentration sufficient to control scale deposition in pipeline <NUM> and associated equipment (for example, downstream equipment <NUM>). For example, scale inhibitor concentrations of <NUM> to <NUM> parts per million (ppm) have been found to be appropriate for surface flowlines and oil-water separation units. Operation of the main valve <NUM>, the bypass valve <NUM>, and the return valve <NUM> controls the flowrate of the bypass flow <NUM>, based on the flowrate of the produced water <NUM> in the pipeline.

In treatment systems where the return line <NUM> is the only fluid exit from the vessel <NUM>, the flowrate of the bypass flow <NUM> equals the flowrate of the return flow <NUM> once the vessel <NUM> is full. In some systems, a pump (not shown) is provided in the vessel <NUM> in order to provide a pressure on the return line <NUM> such that the vessel <NUM> does not have to support the pressure of the fluid in the bypass line <NUM> (for example, the vessel is not full and the pump and one or more of the valves <NUM>, <NUM>, <NUM> are used to control the fill level of the vessel <NUM>).

In this system, the vessel <NUM> has ports <NUM>, <NUM> that can be used to access the interior of the vessel <NUM>. For example, the ports <NUM>, <NUM> can used during tank cleaning and maintenance and during the removal and replacement of depleted solid material. Some systems have more or fewer access ports.

In treatment system <NUM>, the vessel <NUM> is a holding tank storing a volume of produced water. In some systems, the vessel is merely a holding unit for the solid scale inhibitor material <NUM> and the bypass flow <NUM> passes through the holding unit without settling such that the active scale inhibition compounds <NUM> are introduced into the stream of the bypass flow <NUM> and delivered to the return line <NUM>. In some instances, the vessel <NUM> is between <NUM> and <NUM> cubic meters in volume, and the bypass lines <NUM> and return line <NUM> are between <NUM> (<NUM> inches) and <NUM> (<NUM> inches) in internal diameter.

The solid scale inhibitor material <NUM> can be in different forms. In some instances, the solid scale inhibitor material <NUM> is a precipitated solid formed by reacting the active scale inhibition compounds <NUM> with other chemical compounds, such as multi-valence cations such as alkaline earth metal ions (for example, calcium, magnesium, barium, and strontium) or heavy metal ions (for example, iron, nickel, copper, and zinc). In some instances, the solid scale inhibitor material <NUM> is in the form of capsules, where the active scale inhibition compounds <NUM> are enclosed by permeable or semi-permeable materials. In some instances, the solid inhibitor material <NUM> is prepared by adsorbing active scale inhibition compounds <NUM> on porous solid materials with high surface areas, such as activated carbon, zeolite, cluster of nanoparticles and carbon nanotubes, or microporous thin films.

In some instances, the active scale inhibition compounds <NUM> are based on phosphonates, phosphonate esters, or polymeric compounds, or a combination of two or more different types of active scale inhibition compounds. Phosphonate inhibitors include all organic compounds with one or more ortho-phosphate function groups, these include but not limited to amino trimethylene phosphonate, bishexamethylene triamine pentamethylene phosphonate, hexamethylenediamine tetramethylene phosphonate, diethylenetriamine pentamethylene phosphonate, ethylene diamine tetramethylene phosphonate, <NUM>-hydroxyethylidene-<NUM>,<NUM>- diphosphonate, hexamethylene diamine tetramethylene phosphonate, polyamino polyether methylene phosphonate, and <NUM>-phosphonobutane-<NUM>,<NUM>,<NUM>-tricarboxylic acid. Examples of phosphate ester inhibitors are triethanolamine phosphate ester, hydroxyamine phosphate ester, and polyhydric alcohol phosphate ester. Examples of polymeric scale inhibitors are based on polyacrylate or polymaleic function groups such as polyacrylate or polymaleic acid homopolymer, their sulfonated forms, or other co- or multi-polymerirs base on these function groups.

<FIG> is a flowchart of a method <NUM> of treating fluids in an oilfield facility. The method <NUM> is described with reference to the system components shown in <FIG> and <FIG>. The method <NUM> includes diverting a side stream of the fluids from a pipeline <NUM> into a vessel <NUM> containing a solid material <NUM> to release of an active fluid treatment agent <NUM> from the solid material <NUM> into the diverted produced water (step <NUM>). The pipeline can be a surface pipeline with the flow of produced water produced from a well of the oilfield facility. Some methods include continuously diverting the side stream of the produced water from the pipeline into the vessel; and continuously merging the diverted produced fluid containing the active fluid treatment agent back into in the flow of produced water in the pipeline.

In methods for treating produced water to reduce the likelihood of scale formation, the side stream <NUM> of produced water <NUM> is diverted from a pipeline <NUM> of an oilfield facility <NUM> into a vessel <NUM> containing a solid scale inhibitor material <NUM>. The produced water in the vessel <NUM> causes a release of active scale inhibition compounds <NUM> from the solid scale inhibitor material <NUM> into the produced water. In some cases, the active scale inhibition compounds include one or more of: phosphonates, phosphonate esters, and polymeric compounds. The solid scale inhibitor material can be in the form of be in the form of capsules in which the active scale inhibition compounds are enclosed by permeable or semi-permeable materials. The solid scale inhibitor materials also can be in the form of a porous solid material with high surface areas (for example, one or more of: activated carbon, zeolite, cluster of nanoparticles and carbon nanotubes, and microporous thin films) with the active scale inhibition compounds adsorbed into the porous solid material.

In some methods, the active fluid treatment agent includes additionally one or more of a corrosion inhibitor, a paraffin inhibitor, an asphaltene inhibitor, an oxygen scavenger, a biocide, a gas hydrate inhibitor, a salt inhibitor, a foaming agent, an emulsion breaker, and a surfactant.

The diverted produced fluid containing the active fluid treatment agent <NUM> is then merged into the pipeline <NUM> (step <NUM>). In methods for treating produced water to reduce the likelihood of scale formation, the produced water in the vessel <NUM> containing active scale inhibition compounds <NUM> is returned to the pipeline <NUM> of the oilfield facility <NUM> to merge with the remaining flow <NUM> of produced water in the pipeline <NUM>.

The flow rate of the diverted side stream of the produced water is adjusted to change a level of the active fluid treatment agent in the flow of produced water in the pipeline <NUM> (step <NUM>) downstream of the treatment system <NUM>. The flow rate of the diverted side stream can be adjusted by controlling a bypass valve <NUM> upstream of the vessel, by controlling a main valve <NUM> disposed in the pipeline between a location in the pipeline where the side stream is diverted and a location in the pipeline where the side stream is returned, by controlling a return valve downstream of the vessel or some combination of these approaches.

Methods for treating produced water to reduce the likelihood of scale formation can include measuring the level of the scale inhibition compounds in the produced water in the pipeline downstream of the vessel. When adjusting the flow rate of the diverted side stream fails to maintain the level of active scale inhibition compounds in the flow of produced water in the pipeline at or above a threshold level, the solid scale inhibitor material can be replaced. The threshold level can be set based at least in part on the length of flowlines through the oilfield facility.

The control system <NUM> can be a manual control system or some or all of the described functionality ("the functions") can be implemented, at least in part, via a computer program product, for example, a computer program tangibly embodied in an information carrier, such as one or more non-transitory machine-readable media or storage device, for execution by, or to control the operation of, one or more data processing apparatus, for example, a programmable processor, a DSP, a microcontroller, a computer, multiple computers, and/or programmable logic components.

A computer program can be deployed to be executed one or more processing devices at one site or distributed across multiple sites and interconnected by a network.

Actions associated with implementing all or part of the functions can be performed by one or more programmable processors or processing devices executing one or more computer programs to perform the functions of the processes described herein. All or part of the functions can be implemented as, special purpose logic circuitry, for example, an FPGA and/or an ASIC (application-specific integrated circuit).

Components of a computer include a processor for executing instructions and one or more memory devices for storing instructions and data.

While this specification contains many specific implementation details, these should not be construed as limitations on the scope of what may be claimed, but rather as descriptions of features that may be specific to particular embodiments of these systems and methdods. Moreover, although features may be described herein as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.

Moreover, the separation of various system modules and components in the embodiments described herein should not be understood as requiring such separation in all embodiments, and it should be understood that the described program components and systems can generally be integrated together in a single product or packaged into multiple products.

Elements described in detail with reference to one embodiment, implementation, or application optionally may be included, whenever practical, in other embodiments, implementations, or applications in which they are not specifically shown or described. For example, if an element is described in detail with reference to one embodiment and is not described with reference to a second embodiment, the element may nevertheless be claimed as included in the second embodiment. Thus, to avoid unnecessary repetition in the following description, one or more elements shown and described in association with one embodiment, implementation, or application may be incorporated into other embodiments, implementations, or aspects unless specifically described otherwise, unless the one or more elements would make an embodiment or implementation non-functional, or unless two or more of the elements provide conflicting functions.

Particular embodiments of the subject matter have been described. However, other systems and methods can be used to implement the described approaches.

For example, the oilfield facility <NUM> of <FIG> has one treatment system <NUM>. Some oilfield facilities have multiple treatment systems disposed in parallel or in series. For example, facilities with longer flowlines can include multiple treatment systems <NUM> along the flowlines as shown in <FIG>. Alternatively or additionally, individual treatments systems can be operated to increase initial inhibitor concentration at the discharge from the vessel. In facilities with multiple treatment systems at intermediate locations, the spacing between systems is determined by severity of scaling problem and inhibitor release rate from solid inhibitor product.

In another example, the actions recited in the claims can be performed in a different order and still achieve desirable results. In particular, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In certain implementations, multitasking and parallel processing may be advantageous. In addition, other steps may be provided, or steps may be eliminated, from the described flows, and other components may be added to, or removed from, the described systems.

Claim 1:
A method of inhibiting scale in an oilfield facility, the method comprising:
diverting, via a bypass line (<NUM>), a side stream of produced water from a pipeline (<NUM>) into a vessel (<NUM>) containing a solid scale inhibitor material (<NUM>) to release active scale inhibition compounds from the solid scale inhibitor material into the diverted produced water, wherein the active scale inhibition compounds comprise one or more of phosphonates, phosphonate esters, and polymeric compounds;
returning, via a return line (<NUM>), the diverted produced fluid containing the active scale inhibition compounds into the pipeline;
measuring a level of the active scale inhibition compounds produced in the pipeline with a sensor (<NUM>) downstream of a location at which the diverted fluid is returned to the pipeline; and
adjusting a flow rate of the diverted side stream of the produced water to change a level of active scale inhibition compounds in the flow of produced water in the pipeline based at least in part on a signal received from the sensor, wherein adjusting the flow rate of the diverted side stream comprises adjusting a main valve (<NUM>) in the pipeline positioned between a location at which the bypass line connects to the pipeline and a location at which the return line connects to the pipeline.