RU2655669C2 - Foaming of set-delayed cement compositions comprising pumice and hydrated lime - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: method for cementing in a subterranean formation includes providing a set-delayed cement composition comprising water, pumice, hydrated lime, a dispersing agent and a set retarder, wherein the set retarder comprises a phosphonic acid derivative, and the dispersing agent is a polycarboxylic acid ester; foaming the set-delayed cement composition; activating the set-delayed cement composition; introducing the set-delayed cement composition into a subterranean formation; and allowing the set-delayed cement composition to set in the subterranean formation. Also described are additional methods, a foamed set-delayed cement composition and a cementing system.

EFFECT: invention relates to methods and compositions, including those used in various operations performed underground.

27 cl, 3 dwg, 7 tbl

Description

FIELD OF TECHNOLOGY

[001] Cement compositions can be used in various underground operations. For example, during the construction of underground mines, a branch of the pipeline (for example, casing, liners, expandable pipe products, etc.) can be inserted into the wellbore and cemented in place. This process of cementing a branch pipe in place is often referred to as “primary cementing”. In the conventional primary cementing method, the cement composition can be pumped into the annulus between the walls of the wellbore and the outer surface of the pipeline branch located in the specified trunk. The cementitious composition can set in the annulus, thereby forming an annular shell of the hardened, essentially impermeable cement (i.e., cement shell), which can support and position the pipe branch in the wellbore and can connect the outer surface of the branch pipeline with an underground reservoir. Among other things, the cement sheath surrounding the branch of the pipeline functions to prevent the movement of fluids in the annulus, while protecting the branch of the pipeline from corrosion. Cement compositions can also be used in repair cementing methods, for example, to seal cracks or holes in pipe branches or cement shells, to seal highly permeable formation zones or fractures, to place cement plugs, etc.

In underground cementing operations, a wide variety of cement compositions were used. In some cases, delayed setting cement compositions have been used. Slow-setting cement compositions are characterized in that at room temperature (for example, about 80 ° F. (about 27 ° C.)) and when stored at rest, they remain in a suitable fluid state for pumping for at least about one day (for example, at least at least about 7 days, about 2 weeks, about 2 years or more). If necessary, delayed setting cementitious compositions must have the ability to be activated for use, as a result of which acceptable values of compressive strength are manifested. For example, a cement setting accelerator can be added to a delayed setting cement composition, as a result of which the composition sets to form a hardened mass. Among other things, a delayed setting cement composition may be suitable for use in a wellbore, for example, if a cement composition is required in advance. This allows, for example, to store the cement composition until its use. In addition, this allows, for example, to prepare a cement composition in a convenient place, and then move it to the place of work. Accordingly, it is possible to reduce investment by reducing the need for bulk storage at the work site and in mixing equipment. This can be especially useful when performing cementing work at sea, where space on board the vessel may be limited.

Although delayed setting cement compositions have been developed to date, there are difficulties with their successful application in underground cementing operations. For example, delayed setting cement compositions prepared using Portland cement may have undesirable gelation problems that may limit their use and effectiveness in cementing operations. Other delayed setting compositions that have been developed, for example, compositions containing hydrated lime and quartz, may be effective in some operations, but may have limited use at lower temperatures, since they cannot provide a sufficient compressive strength when used in underground formations having a reduced static temperature at the bottom of the well.

BRIEF DESCRIPTION OF THE DRAWINGS

[001] The drawings illustrate certain aspects of some of the embodiments of the present method and should not be used to limit or define this method.

[002] In FIG. 1 shows a system for preparing and delivering a delayed setting cement composition to a wellbore according to some embodiments of the invention.

[003] FIG. 2A shows ground equipment that can be used to place a delayed setting cement composition in a wellbore according to some embodiments of the invention.

[004] FIG. 2B shows the placement of a delayed setting cement composition in the annulus of a wellbore in accordance with some embodiments of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

Typical embodiments of the invention relate to underground cementing operations and, more specifically, according to some embodiments of the invention, to delayed setting cement compositions and methods of using said delayed setting cement compositions in underground formations.

Embodiments of delayed setting cement compositions may generally comprise water, pumice, slaked lime and setting retarder. Optionally, delayed setting cement compositions may further comprise a dispersing agent. Embodiments of delayed setting cement compositions may be foamed. Embodiments of delayed setting cement compositions may preferably remain in a fluidly pumpable state for an extended period of time. For example, delayed setting cement compositions may remain in a pumpable fluid state for at least about 1 day, about 2 weeks, about 2 years, or longer. Preferably, delayed setting cement compositions after activation may exhibit acceptable values of compressive strength at relatively low temperatures. Although delayed setting cement compositions may be suitable for a variety of underground cementing operations, they may be particularly suitable for use in subterranean formations with a relatively low static temperature at the bottom of the well, for example, temperatures below less than about 200 ° F (about 93 ° C) or from about 100 ° F (about 38 ° C) to about 200 ° F (about 93 ° C). In alternative embodiments, delayed setting cement compositions can be used in subterranean formations with static bottomhole temperatures of up to 450 ° F (about 232 ° C) or higher.

Water used in embodiments of delayed setting cement compositions can be obtained from any source, provided that the source does not contain an excessive amount of compounds that may undesirably affect other components contained in delayed setting cement compositions. For example, a delayed setting cement composition may contain fresh water or salt water. Salt water in general may contain one or more salts dissolved in it and may be saturated or unsaturated, as necessary for a particular application. Seawater or saline solutions may be suitable for use in embodiments of the invention. In addition, water may be present in an amount sufficient to form a suspension suitable for pumping. In some embodiments, water may be present in the delayed setting cement composition in an amount of about 33% to about 200% based on the weight of the pumice stone. In some embodiments, water may be present in delayed setting cement compositions in an amount of about 35% to about 70% based on the weight of the pumice stone. One of ordinary skill in the art can determine the appropriate amount of water for a selected application based on the present description.

Embodiments of delayed setting cement compositions may include pumice. In general, pumice is a volcanic rock that can exhibit cementitious properties since it can set and solidify in the presence of hydrated lime and water. Pumice can also be crushed. In general, pumice may have any particle size distribution necessary for a particular application. In some embodiments, pumice may have an average particle size in the range of from about 1 micron to about 200 microns. The average particle size corresponds to d50 values measured using particle size analyzers, such as analyzers manufactured by Malvern Instruments, Worcestershire, United Kingdom. In particular embodiments, the average pumice particle size may be from about 1 micron to about 200 microns, from about 5 microns to about 100 microns, or from about 10 microns to about 50 microns. In one particular embodiment, the average pumice particle size may be less than about 15 microns. An example of a suitable pumice stone is available from Hess Pumice Products, Inc., Malad, Idaho, as a lightweight aggregate DS-325 with a particle size of less than about 15 microns. It should be understood that with too small particle sizes, difficulties with miscibility may occur, while for particles of too large sizes it may not be possible to ensure their effective suspension in these compositions. One skilled in the art can, based on the present description, select a pumice particle size suitable for the selected application.

Embodiments of delayed setting cement compositions may include slaked lime. In this document, the term "slaked lime" will mean calcium hydroxide. In some embodiments, slaked lime can be provided in the form of quicklime (calcium oxide), which hydrates when mixed with water to form slaked lime. Slaked lime can be included in embodiments of delayed setting cement compositions, for example, to produce a hydraulic composition with pumice stone. For example, slaked lime can be included with a weight ratio of pumice to slaked lime ranging from about 10: 1 to about 1: 1, or from 3: 1 to about 5: 1. If slaked lime is present, it can be incorporated into delayed setting cement compositions in an amount of, for example, from about 10% to about 100% based on pumice weight. In some embodiments, slaked lime may be present in an amount varying between any of about 10%, about 20%, about 40%, about 60%, about 80%, or about 100% based on pumice weight, and / or in an amount including any of the listed values. According to some embodiments of the invention, the cementitious components present in the cementitious delayed setting composition can essentially consist of pumice and slaked lime. For example, cementitious components can mainly contain pumice and slaked lime without any additional components (e.g. Portland cement, fly ash, slag cement) that hydraulically set in the presence of water. A person skilled in the art, based on the present description, will be able to determine the appropriate amount of slaked lime necessary for inclusion for the selected application.

Embodiments of delayed setting cement compositions may include a setting retarder. A variety of retarders may be suitable for use in delayed setting cement compositions. For example, a set retarder may include phosphonic acids such as ethylene diamine tetra (methylene phosphonic acid), diethylene triamine penta (methylene phosphonic acid) and the like; lignosulfonates such as sodium lignosulfonate, calcium lignosulfonate and the like; salts such as tin sulfate, lead acetate, monobasic calcium phosphate, organic acids such as citric acid, tartaric acid and the like; cellulose derivatives such as hydroxyl ethyl cellulose (HEC) and carboxymethyl hydroxyethyl cellulose (CMHEC); synthetic copolymers or ternary polymers containing sulfonate groups and carboxylic acid groups, such as copolymers of functionalized acrylamide sulfonate and acrylic acid; borate compounds such as alkali metal borates, sodium metaborate, sodium tetraborate, potassium pentaborate; derivatives thereof or mixtures thereof. Examples of suitable setting retarders include, but are not limited to, phosphonic acid derivatives. One example of a suitable retarder is the Micro Matrix ^® Cement Retarder, available from Halliburton Energy Services, Inc. In general, a setting retarder may be present in delayed setting cement compositions in an amount sufficient to retard setting during the required time. In some embodiments, the setting retarder may be present in delayed setting cement compositions in an amount of about 0.01% to about 10% based on the weight of the pumice stone. According to particular embodiments of the invention, the setting retarder may be present in an amount ranging between any of about 0.01%, about 0.1%, about 1%, about 2%, about 4%, about 6%, about 8% or about 10% relative to the mass of pumice, and / or in an amount including any of the listed values. One skilled in the art can, based on the present description, determine the appropriate amount of setting retarder to be included for the selected application.

As mentioned previously, embodiments of delayed setting cement compositions may optionally contain a dispersing agent. Examples of suitable dispersing agents include, without limitation, sulfonated dispersants formaldehyde-based (e.g., sulfonated acetone-formaldehyde condensation product), examples of which may include Daxad ^® (Daksad) 19 which is available from Geo Specialty Chemicals, Ambler, Pennsylvania. Other suitable dispersants may be esters of polycarboxylic acids such as Liquiment ^® (Likument) 5581F and Liquiment ^® (Likument) 514L, which is available from BASF Corporation Houston, Texas; or Ethacryl G, available from Coatex, Genet, France. A further example of a suitable commercially available dispersant is the CFR ^™ -3 dispersant, which is available from Halliburton Energy Services, Inc, Houston, Texas. Of particular importance for the following examples is the fact that the dispersing agent Liquiment ^® (Likument) 514L contains 36 wt.% Of a polycarboxylic acid ester in water. Although various dispersing agents can be used in accordance with embodiments of the invention, polycarboxylic acid esters used as dispersing agents may be particularly suitable for use in some embodiments of the invention. Without being limited by theory, it is believed that polycarboxylic acid esters used as dispersing agents can synergistically interact with other components of the delayed setting cement composition. For example, it is believed that polycarboxylic acid esters used as dispersing agents can react with certain setting retarders (e.g., phosphonic acid derivatives), resulting in a gel in the formation that suspends pumice and slaked lime in the composition over a long period of time.

In some embodiments, the dispersant can be included in delayed setting cement compositions in an amount of about 0.01% to about 5% based on pumice weight. According to particular embodiments of the invention, the dispersing agent may be present in an amount varying between any of about 0.01%, about 0.1%, 0.5%, about 1%, about 2%, about 3%, about 4% or about 5% relative to the mass of pumice, and / or in an amount including any of the listed values. One skilled in the art can, based on the present description, determine the appropriate amount of dispersant needed to be included for the selected application.

Embodiments of delayed setting cement compositions may contain an additive to improve mechanical properties. Additives to improve mechanical properties can be included in embodiments of delayed setting compositions, for example, to provide an appropriate compressive strength and long-term structural integrity. These properties can be influenced by stresses, loads, temperature, pressure and impact effects of the underground environment. Examples of additives to improve mechanical properties include fibers, such as, inter alia, graphite carbon fibers, glass fibers, steel fibers, mineral fibers, silica fibers, polyester fibers, polyamide fibers and polyolefin fibers. Specific examples of graphite carbon fibers include fibers derived from polyacrylonitrile, rayon, and petroleum pitch. When using these additives to improve mechanical properties may be present in an amount of from about 0.01% to about 5% relative to the weight of pumice. According to particular embodiments of the invention, said additives for improving mechanical properties may be present in an amount ranging between any of about 0.01%, about 0.1%, 0.5%, about 1%, about 2%, about 3%, about 4%, or about 5%, relative to the weight of pumice, and / or in an amount including any of the listed values. Based on the present description, one skilled in the art will be able to determine the appropriate amount of additives to be included to improve mechanical properties for the selected application.

Other additives suitable for use in underground cementing operations may also be included in embodiments of delayed setting cement compositions. Examples of such additives include, but are not limited to, weighting agents, lightweight additives, gas generating additives, absorption control materials, filtration control additives, water loss reducing agents, antifoam agents, blowing agents, thixotropic additives, and combinations thereof. According to embodiments of the invention, one or more of the listed additives can be added to the delayed setting cement composition after storage, but before the said delayed setting cement composition is placed in an underground formation. A person skilled in the art based on the present description will be able to easily determine the type and amount of additive suitable for a particular application and obtain the desired result.

Those skilled in the art will recognize that embodiments of delayed setting cement compositions generally should have a density suitable for a particular application. For example, delayed setting cement compositions can have a density in the range of about 4 pounds per gallon (“lb / gal”) ((about 0.5 kg / l)) to about 20 pounds / gal (about 2.4 kg / l) . In some embodiments, delayed setting cement compositions may have a density in the range of about 8 lb / gal (about 0.96 kg / l) to about 17 lb / gal (about 2.0 kg / l). Embodiments of delayed setting cement compositions may be foamed or not foamed, or may contain other means for lowering their densities, such as hollow microspheres, low density elastic beads, or other density reducing additives known in the art. According to embodiments of the invention, the density can be reduced after storage of the composition, but before it is placed in the subterranean formation. Those skilled in the art can determine, based on the present description, a density suitable for a particular application.

As described above, embodiments of delayed setting cement compositions may be foamed. Embodiments of delayed setting cement compositions can be foamed to provide a lightweight composition that does not unduly affect the formations through which the wellbore passes. In addition to a small mass, the foamed composition may also have the property of improving the ability of the composition to maintain pressure and to prevent the flow of formation fluids into the composition and through the composition during its movement. Foamed compositions may also be preferred because they have poor fluid loss properties, which thus limits losses in fluid circulation. In addition, foamed compositions during setting may also have a lower modulus of elasticity than the modulus of non-foamed compositions, which is often necessary because this allows the resulting cemented cement composition to withstand the loads acting on the composition at the place of use.

In particular embodiments, the delayed setting cement composition can be foamed at the location of the well. For example, delayed setting cementitious compositions can be foamed immediately prior to use. Embodiments can be foamed with a foaming agent and by trapping gas in delayed setting cement compositions. According to particular embodiments of the invention, a foaming additive and gas can be introduced after combining the composition with an activator. Slow setting cementitious compositions can be foamed, for example, to obtain a low density cementitious delayed setting composition.

The gas used to foam the composition may be any suitable gas for foaming, including, but not limited to: air, nitrogen, and combinations thereof. As a rule, the gas should be in an amount sufficient to obtain the desired foam. Foaming additives can be included in embodiments of the invention, for example, to facilitate foaming and / or stabilization of the resulting foam obtained using these additives.

According to particular embodiments of the invention, the foaming agent may include a surfactant or a combination of surfactants that reduce the surface tension of water. For example, a blowing agent may contain anionic, nonionic, amphoteric (including zwitterionic surfactants), a cationic surfactant, or mixtures thereof. Examples of suitable blowing agents include, but are not limited to: betaines; anionic surfactants such as hydrolyzed keratin; amine oxides such as alkyl or alkene dimethyl amine oxides; cocoamidopropyl dimethyl amine oxide; methyl ester sulfonates; alkyl or alkene amidobetaines such as cocoamidopropyl betaine; alpha olefin sulfonates; quaternary surfactants such as tall trimethyl ammonium chloride and trimethyl coco ammonium chloride; C8 to C22 alkyl ethoxylate sulfates; and their combinations. Specific examples of suitable blowing agents include mixtures of the ammonium salt of an alkyl ether sulfate, the cocoamidopropyl betaine surfactant, the cocoamidopropyl dimethyl amine oxide surfactant, sodium chloride and water; mixtures of a surfactant, an ammonium salt of an alkyl ether sulfate, a surfactant cocoamidopropylhydroxysultaine, a surfactant cocoamidopropyl dimethyl amine oxide, sodium chloride and water; mixtures of a surfactant, ethoxylated alcohol ether sulfate, alkyl or alkene amidopropyl betaine and a surfactant alkyl or alkene dimethyl amine oxide; aqueous solutions of the surfactant alpha olefin sulfonate and the surfactant betaine; and their combinations. Examples of suitable blowing agents are ZONESEALANT ^™ 2000 Agent and 1026 ^™ Foaming Agent, both of which are available from Halliburton Energy Services Inc., Houston, Texas. Embodiments may be foamed to provide foam quality in the range of from about 5% to about 80% and, more specifically, from about 18% to about 38%. As used herein, the term “foam quality” refers to the volume of trapped gas and is defined according to the following formula: Foam Quality = (Total Foam Volume - Liquid Volume) / Total Foam Volume.

As mentioned previously, cementitious compositions may exhibit delayed setting as they remain in a pumpable fluid state for at least one day (e.g., at least about 1 day, about 2 weeks, about 2 years or longer) at room temperature when stored at rest. For example, delayed setting cement compositions may remain in a pumpable fluid state for a period of from about 1 day, about 2 weeks, about 2 years or longer. According to some embodiments of the invention, delayed setting cement compositions may remain in a pumpable fluid state for at least about 1 day, about 7 days, about 10 days, about 20 days, about 30 days, about 40 days, about 50 days, approximately 60 days, approximately 2 years or longer. The fluid is considered to be in a pumpable fluid state when said fluid has a consistency of less than 70 Burden consistency units (“Bc”), measured on a high pressure and high temperature consistometer at room temperature (eg, about 80 ° F) (approximately 27 ° С)) according to the procedure for determining the thickening time of cement described in API RP Practice 10B-2, Recommended Practice for Testing Well Cements , first edition, July 2005.

If necessary for use, the implementation options of cement compositions of delayed setting can be activated (for example, by combining with an activator) to ensure setting, resulting in a hardened mass. For example, embodiments of delayed setting cement compositions can be activated to allow setting to produce a hardened mass over a period of time ranging from about 1 hour to about 12 hours. For example, embodiments of delayed setting cement compositions can set to form a set mass over a period of time that varies between any of about 1 day, about 2 days, about 4 days, about 6 days, about 8 days, about 10 days, or approximately 12 days, and / or including any of the listed values.

In some embodiments, delayed setting cement compositions can set in such a way that they have the required compressive strength after activation. The compressive strength is generally the ability of a material or structure to withstand pusher forces directed along the axis. The compressive strength can be measured at a predetermined point in time after activating the delayed setting cementitious composition, while the resulting composition is maintained under specific temperature and pressure conditions. The compressive strength can be measured either using the test method with the destruction of the sample, or using a non-destructive method. When applying the method with the destruction of the sample physically determine the strength of the samples of the compositions of the fluids for processing at various points in time by crushing these samples in a machine for compression testing. The compressive strength is calculated from the breaking load divided by the cross-sectional area that resists the load and is given in units of pound-force per square inch (psi). Non-destructive methods typically use an ultrasonic cement analyzer (“UCA”), available from the Fann Instrument Company, Houston, Texas. The compressive strengths can be determined according to API RP 10B-2, Recommended Practice for Testing Well Cements , First Edition, July 2005.

For example, a delayed setting cement composition can develop a 24-hour compressive strength in the range from about 50 psi (about 345 kPa) to about 5000 psi (about 34.5 MPa), alternatively from about 100 psi (about 689 kPa) to about 4,500 psi (about 31.0 MPa) or alternatively from about 500 psi (about 3447 kPa) to about 4,000 psi (about 27.6 MPa). In some embodiments, the delayed setting cement composition can develop in 24 hours a compressive strength of at least about 50 psi (about 345 kPa), at least about 100 psi (about 689 kPa), at least about 500 psi (approximately 3447 kPa) or more. In some embodiments, the compressive strength can be determined using destructive or non-destructive methods in the temperature range from 100 ° F (about 38 ° C) to 200 ° F (about 93 ° C).

Embodiments of the invention may include the addition of delayed setting cement activator to cement compositions. Examples of suitable cement setting agents include, but are not limited to: amines such as triethanolamine, diethanolamine; silicates such as sodium silicate; zinc formate; calcium acetate; hydroxides of elements of groups IA and IIA, such as sodium hydroxide, magnesium hydroxide and calcium hydroxide; monovalent cation salts such as sodium chloride; salts of a divalent cation, such as calcium chloride; nanosilica (i.e. silica with a particle size of less than or equal to about 100 nanometers); polyphosphates; and their combinations. In some embodiments, a combination of a polyphosphate and a salt of a monovalent cation can be used for activation. The monovalent cation salt may be any salt that dissociates to form a monovalent cation, such as sodium and potassium salts. Specific examples of suitable salts of monovalent cations include potassium sulfate and sodium sulfate. A variety of other polyphosphates can be used to activate delayed setting cement compositions in combination with a monovalent cation salt, including polymeric metaphosphate salts, phosphate salts, and combinations thereof. Specific examples of the polymeric metaphosphate salts that can be used include sodium hexametaphosphate, sodium trimetaphosphate, sodium tetramethaphosphate, sodium pentametaphosphate, sodium heptametaphosphate, sodium octametaphosphate, and combinations thereof. A specific example of a suitable cement setting agent comprises a combination of sodium sulfate and sodium hexametaphosphate. In particular embodiments, an activator may be provided and added to the delayed setting cement composition in the form of a fluid additive, for example, a fluid additive containing a monovalent cation salt, polyphosphate and, optionally, a dispersing agent.

The cement setting agent should be added to embodiments of the delayed setting cement composition in an amount sufficient to activate the delayed setting cement composition to allow setting to produce a hardened mass. According to some embodiments of the invention, the cement setting agent can be added to the delayed setting cement composition in an amount of about 1% to about 20% based on the weight of the pumice stone. According to particular embodiments of the invention, the cement setting agent may be present in an amount varying between any of about 1%, about 5%, about 10%, about 15%, or about 20% relative to the weight of the pumice stone, and / or in an amount including any of the listed values. One skilled in the art can, based on the present description, determine the appropriate amount of cement setting activator to be included for the selected application.

As will be appreciated by those skilled in the art, embodiments of delayed setting cement compositions can be used in various underground operations, including primary and repair cementing. In some embodiments, a delayed setting cement composition comprising water, pumice, slaked lime, setting retarder, and optionally a dispersing agent can be provided. The delayed setting cementitious composition can be introduced into the subterranean formation and left in the specified formation for setting. Herein, introducing a delayed setting cement composition into a subterranean formation includes introducing into any part of the subterranean formation, including, without limitation, into a wellbore drilled in the subterranean formation, into the bottom hole zone surrounding the wellbore, or both a place. Embodiments of the invention may further include activating a delayed setting cement composition. Activation of the delayed setting cement composition may include, for example, adding a cement setting activator to the delayed setting cement composition.

In some embodiments, a delayed setting cement composition comprising water, pumice, slaked lime, setting retarder, and optionally a dispersing agent can be provided. The delayed setting cementitious composition may be stored, for example, in a tank or other suitable container. The delayed setting cementitious composition can be left in storage for a desired period of time. For example, a delayed setting cement composition may remain in storage for a period of time of about 1 day, about 2 weeks, about 2 years, or longer. For example, a delayed setting cement composition may remain in storage for a period of about 1 day, about 2 days, about 5 days, about 7 days, about 10 days, about 20 days, about 30 days, about 40 days, about 50 days, about 60 days, about 2 years or longer. In some embodiments, the delayed setting cement composition may remain in storage for a period of time from about 1 day to about 2 years or longer. After this, the delayed setting cement composition can be activated, for example, by adding a cement setting agent, which is introduced into the subterranean formation, and left to set in said formation. Optionally, the delayed setting cementitious composition can be foamed before being introduced into the subterranean formation.

In primary cementing embodiments, for example, delayed setting cement compositions can be introduced into the annular space between a pipe located in the wellbore and the walls of the wellbore (and / or a larger pipe in the wellbore), while the wellbore passes through an underground layer. The delayed setting cementitious composition can be left to set in an annular space to form an annular casing of hardened cement. The delayed setting cementitious composition may form a barrier preventing the movement of fluids in the wellbore. In addition, the delayed setting cement composition may, for example, provide support to the pipeline in the wellbore.

In the case of primary cementing embodiments, the delayed setting cement composition may be used, for example, in high pressure cementing operations or in the placement of cement plugs. For example, a delayed setting composition can be placed in a wellbore to plug a hole, such as a cavity or crack, present in the formation, in gravel packing, in a pipe, in a cement sheath and / or between a cement sheath and a pipe (for example, a micro-gap between the casing and cement stone).

One typical embodiment of the invention includes a cementing method in a subterranean formation, comprising: providing a delayed setting cement composition comprising water, pumice, slaked lime and setting retarder; providing foaming cement composition delayed setting; activation of the foamed delayed setting cement composition; the introduction of foamed cement composition delayed setting in the subterranean formation; and setting the foamed cement composition of the delayed setting in the subterranean formation.

One typical embodiment of the invention includes a foamed delayed setting cement composition comprising: water, pumice, slaked lime, a foaming agent, entrained gas, and a setting retarder.

One typical embodiment of the invention includes a cementing system comprising: a delayed setting cement composition comprising: water, pumice, slaked lime, setting retarder, a foaming additive for foaming the delayed setting cement composition; gas for foaming a delayed setting cement composition; and a cement setting activator for activating a delayed setting cement composition.

Turning now to FIG. 1, which shows the preparation of a delayed setting cement composition according to typical embodiments of the invention. In FIG. 1 shows a system 2 for producing a delayed setting cement composition and delivery to a wellbore according to some embodiments of the invention. As shown, the delayed setting cement composition can be mixed in mixing equipment 4, such as, for example, a jet mixer, a recirculation mixer or a batch mixer, and then pumped into the wellbore using pumping equipment 6. According to some embodiments of the invention, the mixing equipment 4 and pumping equipment 6 can be located on one or more cement trucks, as will be appreciated by those skilled in the art. According to some embodiments of the invention, a jet mixer can be used, for example, to provide continuous mixing of lime / settable material with water when it is pumped into the wellbore.

A typical method for placing a delayed setting cement composition in a subterranean formation will now be described with reference to FIG. 2A and 2B. In FIG. 2A shows ground equipment 10 that can be used to place a delayed setting cement composition according to some embodiments of the invention. It should be noted that, although in FIG. 2A generally depicts a land-based operation, those skilled in the art will readily understand that, within the scope of the present invention, the principles described herein are equally applicable to underwater operations in which floating or offshore platforms and drilling rigs are used. As shown in FIG. 2A, ground equipment 10 may include a cementing unit 12, which may include one or more cement trucks. As will be appreciated by those skilled in the art, the cementing unit 12 may include mixing equipment 4 and pumping equipment 6 (for example, FIG. 1). Using the cementing unit 12, the delayed setting cement composition 14 can be pumped through the feed pipe 16 into the cementing head 18, which allows the delayed setting cement composition 14 to be moved down into the well.

With reference to FIG. 2B, delayed setting cement composition 14 can be placed in subterranean formation 20 according to typical embodiments of the invention. As shown, in the subterranean formation 20, a wellbore 22 can be drilled. Although the wellbore 22 is shown to extend into the subterranean formation 20 generally vertically, the principles described herein also apply to wellbores that extend through the subterranean formation 20 at an angle, such as horizontal and inclined wellbores. As shown, the wellbore 22 comprises walls 24. According to the illustrated embodiment, a conductor casing 26 is inserted into the wellbore 22. The conductor casing 26 can be cemented to the walls 24 of the wellbore 22 by a cement sheath 28. According to the illustrated embodiment, one or more additional pipelines (for example, an intermediate casing string, production casing string, liners, etc.) may also be located in the wellbore 22, p shown in the figure in the form of a casing string 30. As shown, in the wellbore there is an annulus 32 formed between the casing string 30 and the walls 24 of the wellbore 22 and / or the conductive casing string 26. One or more centralizers can be attached to the casing string 30. 34, for example, to center the casing 30 in the wellbore 22 before and during the cementing operation.

As shown in FIG. 2B, the delayed setting cement composition 14 can be pumped down into the inside of the casing 30. It is possible to allow the delayed setting cement composition 14 to flow into the inside of the casing 30 through the casing shoe 42 at the bottom of the casing 30 and around the casing 30 into the annulus space 32 of the wellbore. The delayed setting cement composition 14 can be left to set in the annulus 32 of the wellbore, for example, to provide a cement sheath that supports and sets the casing 30 in the desired position in the wellbore 22. Although not shown, other methods of introducing a delayed setting cement composition 14 can also be used. For example, you can use the methods of reverse circulation, including the introduction of the cement composition 14 delayed setting in the subterranean formation 20 through the annular space 32 of the wellbore instead of introducing through the casing 30.

When introduced, the delayed setting cement composition 14 can displace other fluids 36, such as drilling fluids and / or displacing fluids, which may be present in the interior of the casing 30 and / or in the annulus 32 of the wellbore. At least a portion of the displaced fluids 36 may exit the annulus 32 of the wellbore through the flow line 38 and settle, for example, in one or more sewage ponds 40 (for example, in a mud storage barn), as shown in FIG. 2A. Turning again to FIG. 2B, which illustrates that prior to cementing into the wellbore 22, prior to the introduction of the delayed setting cement composition 14, a lower plug 44 may be introduced, for example, to allow the delayed setting cement composition 14 to separate from the fluids 36 that may be located inside the casing 30. After as the bottom plug 44 reaches the collar 46 for hanging the column, the diaphragm or other suitable device must break to allow the delayed setting cement composition 14 to pass through the bottom timid 44. In FIG. 2B, the bottom plug 44 is shown on a sleeve 46 for suspending a column. According to the illustrated embodiment, an upper plug 48 can be inserted into the wellbore 22 after the delayed setting cement composition 14. The upper plug 48 can separate the delayed setting cement composition 14 from the displacement fluid 50 and also push the delayed setting cement composition 14 through the bottom plug 44.

Typical delayed setting cement compositions described herein can directly or indirectly affect one or more components or parts of equipment related to the preparation, delivery, re-picking, recycling, reuse and / or removal of the described delayed setting cement compositions. For example, the delayed setting cementitious compositions described may directly or indirectly affect one or more mixers, associated mixing equipment, drilling fluid storage pits, storage facilities or storage devices, composition separators, heat exchangers, sensors, meters, pumps, compressors and etc. used to generate, store, monitor, regulate and / or repair typical delayed setting cement compositions. The described delayed setting cement compositions can also directly or indirectly affect any transport or delivery equipment used to transport the delayed setting cement compositions to or down into the well, such as, for example, any transportation vessels, oil pipelines, pipelines, trucks, pipe products and / or pipes used for the composite movement of delayed setting cement compositions from one place to another, any suckers, compressors, or motors (e.g., ground or submersible) used to drive the cementitious delayed cement compositions, any valves or associated articulation points used to control the pressure or flow rate of the cementitious delayed cement compositions, and any sensors (i.e. pressure and temperature), measuring instruments and / or combinations thereof, etc. In addition, the described delayed setting cement compositions can directly or indirectly affect various submersible equipment and tools that can come into contact with the delayed setting cement compositions, such as, but not limited to, the barrel casing, the barrel liner, production casing, drilling insert columns, drill string, coiled tubing, wire rope, auxiliary cable, drill pipe, couplings for drilling operations, downhole turbine engines, submersible pumps motors and / or pumps, cementing pumps, surface mounted motors and / or pumps, centralizers, turbulizers, scrapers, floats (e.g. shoes, couplings, valves, etc.), downhole logging probes and associated telemetry equipment, mechanisms control valves or fittings (for example, electromechanical devices, hydromechanical devices, etc.), sliding couplings, standard couplings, plugs, strainers, filters, flow control devices (for example, flow regulators, autonomous regulators flow, outflow regulators, etc.), connections (for example, electro-hydraulic wet connector, dry connector, inductive connector, etc.), control lines (for example, electric, fiber optic, hydraulic, etc.), technical inspection lines, drill bits and reamers, sensors or distributed sensors, immersion heat exchangers, valves and associated control devices, tool seals, packers, cement plugs, bridge plugs and other devices for isolating the borehole or lump ponents, etc.

EXAMPLES

For a better understanding of the present embodiments of the invention, the following examples of some aspects of certain embodiments of the invention are provided. In no way should be considered that the following examples limit or determine the scope of the embodiments of the invention.

Example 1

A sample cement composition retardation was prepared using the following components: pumice (lightweight aggregate DS-325), hydrated lime, a dispersing agent (Liquiment ^® (Likument) 5581F), primary retarder (retarder cement setting Micro Matrix ^® (Micro Matrix)), additive weighting (weighting additives MicroMax ^® (MicroMax) which is available from Halliburton Energy Services, Inc., Houston, TX), a secondary retarder (cement setting retarder HR ^® -5, which is available from Halliburton Energy Services, Inc. Houst he, Texas), Portland Class H cement and water. Each component, with the exception of the primary moderator (Micro Matrix ^® cement setting retarder ), is presented as a percentage of pumice mass (bwoP). Primary moderator was measured in gallon units per 46 lb (approximately 21 kg ) pumice bag (gal / bag). The composition is shown below in table 1.

Table 1

The composition of the sample cement composition delayed setting

Material amount Units Mass (g) % bw in total Pumice one hundred % bwoP 58682.7 55.56 Slaked lime twenty % bwoP 11736.5 11.11 Dispersing agent 0.5 % bwoP 291.1 0.28 Primary moderator 0.06
(0.23 L / bag) gal / bag 734.6 0.70 Weighting Additive 2 % bwoP 1173.7 1,11 Secondary retarder 0.5 % bwoP 293.4 0.28 Portland cement 2 % bwoP 1173.7 1,11 Water 53.7 % bwoP 31534.5 29.86 Total - - 105620.2 one hundred

The sample in Example 1 for more than 40 days remained in a flowable state, amenable to mixing, suitable for pumping, and stable without precipitation of solids or gel formation. The measured density of the sample was 13.5 pounds per gallon (approximately 1.6 kg / l). To maintain optimal rheological properties of the suspension, minimal doses of dispersing agent were added during the storage period. Such a typical sample served as a base suspension for the remaining examples described below.

Example 2

The rheological properties of a sample of the delayed setting cement composition described in Example 1 were measured after storage of the samples at room temperature and pressure for 41 days. After obtaining the rheological properties of the samples were determined using a Fann Model 35A viscometer and No. 2 spring using a Fann Yield Stress Adapter according to the procedure described in API RP Practice 10B-2, Recommended Practice for Testing Well Cements . The results of this test are shown below in table 2.

table 2

Viscosity test

Sample age (days) Indications FYSA (Fann Yield Stress Adapter) Rpm 3 6 one hundred 200 300 3D 6D 41 Average 13 13 35 56 75.5 5 four

Example 3

Three samples of delayed setting cement compositions, samples 1-3, and two control samples, control samples 1 and 2 were prepared from the base suspension described in Example 1, 1026 ^™ foaming agent, a foaming additive, was added to each of the three samples in varying amounts after 41 days. In addition, a cement setting activator, CaCl ₂ , was added to sample 2 and control sample ₂ . The amount of cement setting activator added to each sample was sufficient to deliver a delayed setting of 5% of the activator to the cement composition relative to the weight of the pumice stone. The densities of the base and foamed compositions were measured. In addition, the ultimate tensile strength was measured using a mechanical press according to API RP Practice 10B-2, Recommended Practice for Testing Well Cements . In addition, the ultimate compressive strength was measured by curing samples in a 2 ”× 4” plastic cylinder ( 5.08 cm × 10.16 cm) placed in a water bath at 190 ° F (approximately 88 ° C), s the formation of cured cylinders. Immediately after removal from the water bath, tensile strengths were determined for compressive stress using a mechanical press according to API RP 10B-2, Recommended Practice for Testing Well Cements . The results of this test are shown below. The compressive strengths given are the average of the two cylinders of each specimen. Samples and control samples were cured at a pressure of 1 atmosphere, 190 ° F (approximately 88 ° C); measurements of compressive strength were carried out after 72 hours.

Table 3

Composition and characteristics of the composition

Sample 1 Sample 2 Sample 3 Control sample 1 Control sample 2 Sample weight (g) 1363.2 1363.2 1363.2 817.5 817.5 Foaming Additive (g) 8.14 12.21 fourteen - - Activator (g) - 37.87 - - 25.8 The density of the base composition (lbs / gal) 13.5
(approximately 1.6 kg / l) 13.5
(approximately 1.6 kg / l) 13.5
(approximately 1.6 kg / l) 13.5
(approximately 1.6 kg / l) 13.3 *
(approximately 1.59 kg / l) The density of the foamed composition (lb / gal) eleven
(approximately 1.3 kg / l) 9.1
(approximately 1.1 kg / l) 9.2
(approximately 1.1 kg / l) - - Foam quality 19% 33% 32% - - Compression Strength (psi) 639.37
(approximately 4,408 kPa) 534.45
(approximately 3684 kPa) 135.18
(approximately 932 kPa) 1222.46
(approximately 8428 kPa) 1360.14
(approximately 9377 kPa)

* Density of control sample 2 with activator.

Along with the characteristics shown in table 3, the stability of the foam was measured in samples 1-3, both in the suspension state and in the trapped state. The data obtained are shown below in table 4.

Table 4

Foam Stability Measurement Results

Foam stability Sample 1 Sample 2 Sample 3 Suspension Captured state Suspension Captured state Suspension Captured state More than a trace of free fluid? No No No No No No Bubbles on the surface of adhesion of bubbles (rupture, expansion, merging)? No No No No No No Excessive reduction in column height? No No No No No No Signs of stratification of density (banding or dark coloring from top to bottom)? No No No No No No

To measure the density of the suspension of samples 1-3 in the upper, middle and lower parts, the Archimedes method was used. Densities that were close in weight from top to bottom indicate stable foam, while a significant change in densities indicates foam instability. All units are in pounds per gallon. The data obtained are shown below in table 5.

Table 5

Density uniformity

Archimedes Method Example 1 Example 2 Example 3 Top (lb / gal) 10.50
(approximately 1.26 kg / l) 8.95 (approximately 1.07 kg / l) 9.26 (approximately 1.11 kg / l) Mid Part (lb / gal) 10.52
(approximately 1.26 kg / l) 8.99 (approximately 1.08 kg / l) 9.30 (approximately 1.11 kg / l) Bottom (lb / gal) 10.46
(approximately 1.25 kg / l) 8.83 (approximately 1.06 kg / l) 9.25 (approximately 1.11 kg / l)

In conclusion, the rheological properties of the foamed samples 1-3 were measured using the same method used in Example 2 to measure the rheological properties of the base suspension. In table 6 below, the base suspension is designated as control sample 1. The rheological data are shown in table 6 below.

Table 6

Viscosity test

Indications FYSA (Fann Yield Stress Adapter) Density (lb / gal) Rpm 3 6 one hundred 200 300 3D 6D Control sample 1 13.5
(approximately 1.6 kg / l) Average 13 13 35 56 75.5 5 four Sample 1 eleven
(approximately 1.3 kg / l) Average 10 10.5 33.5 50.25 65.5 3,5 2.5 Sample 2 9.1
(approximately 1.1 kg / l)
Average 2.25 3 17.5 29.5 40 1,5 one Sample 3 9.2
(approximately 1.1 kg / l) Average 17 17.5 40.5 56.5 70.5 12 9

Thus, Example 3 indicates that the foamed suspensions exhibit a good compressive strength while maintaining suitable rheological properties and uniform density.

Example four

From the base suspension described in Example 1, two samples of delayed setting cement compositions were prepared, samples 4 and 5. Cement setting activator, CaCl ₂ , was added to the samples in an amount sufficient to deliver 5% relative to the delayed setting cement composition of the cement pumice masses. Sample 5 further included graphite carbon fibers in an amount of about 0.18% based on pumice weight. Graphite carbon fibers were carbon PAN fibers obtained from polyacrylonitrile. To each of the samples was added 1026 ^™ foaming agent, a foaming additive, in an amount of 0.18% relative to the weight of pumice. In addition, the ultimate compressive strength was measured by curing samples in a 2 ”× 4” plastic cylinder (5.08 cm × 10.16 cm) placed in a water bath at 190 ° F (approximately 88 ° C), s the formation of cured cylinders. Immediately after removal from the water bath, tensile strengths were determined for compressive stress using a mechanical press according to API RP 10B-2, Recommended Practice for Testing Well Cements . The results of this test are shown below. The compressive strengths shown are the average of the three cylinders of each specimen. Samples and control samples were cured at a pressure of 1 atmosphere, 190 ° F (approximately 88 ° C); measurements of compressive strength were carried out after 72 hours.

Table 7

Composition and characteristics of the composition

Sample 4 Sample 5 Base suspension (g) 1000 1000 Carbon fiber (g) - 10 Activator (g) 27.8 27.8 Foaming Additive (g) 10 10 The density of the base composition (lbs / gal) 13.5
(approximately 1.6 kg / l) 13.5
(approximately 1.6 kg / l) The density of the foamed composition (lb / gal) 8.33
(approximately 0.99 kg / l) 8.33
(approximately 0.99 kg / l) Compression Strength (psi) 62
(approximately 427 kPa) 143
(approximately 986 kPa)

It should be understood that the proposed compositions and methods are described as “comprising” or “containing” various components or steps, and such compositions and methods may also “consist essentially of” or “consist of” various components and steps. Moreover, it is understood that the singular nouns used in the claims indicate one or more elements in this document.

For brevity, only certain ranges are explicitly provided herein. However, ranges from any lower limit can be combined with any upper limit to provide a range not explicitly given, and also ranges from any lower limit can be combined with any other lower limit to provide a range not explicitly shown in the same way , ranges from any upper limit can be combined with any other upper limit to provide a range not explicitly given. In addition, whenever a numerical range with a lower limit and an upper limit is given, any number and any included range falling within the scope of the specified range are specifically described. In particular, it is understood that each range of values (in the form of “from about a to about b” or equivalent to “from about a to b” or equivalent to “from about ab”) described herein sets each number and range included to a wider range of values, even if not explicitly described. Thus, each point or individual value can serve as its own lower or upper limit, combined with any other point or individual value or any other lower or upper limit, to obtain a range not explicitly given.

Thus, the present embodiments of the invention are well adapted to achieve the aforementioned objectives and advantages, as well as the objectives and advantages that are inherent in this invention. The specific embodiments of the invention described above are only illustrative and can be modified and practiced in various, but equivalent ways, obvious to those skilled in the art who benefit from the ideas described herein. Although individual embodiments are contemplated, the present invention covers all combinations of all of these embodiments. In addition, do not imply any restrictions on the details of the structure or device proposed in this document, except those described in the following claims. In addition, the terms in the claims have their simple ordinary meaning, unless otherwise expressly and clearly defined by the patent holder. Therefore, it is obvious that the specific illustrative embodiments of the invention described above can be changed or modified, and it is believed that all such options are within the scope and essence of the present invention. If there is any contradiction in the application of a word or term in the present description of the invention and in one or more patent (s) or other documents that may be incorporated into this document by reference, definitions shall be adopted that correspond to this description .

Claims (46)

1. A method of cementing in an underground formation, including: providing a delayed setting cement composition comprising water, pumice, slaked lime, a dispersing agent and a setting retarder, the setting retarder containing a phosphonic acid derivative and the dispersing agent being a polycarboxylic acid ester; foaming of a delayed setting cement composition; activation of the delayed setting cement composition; the introduction of a cement composition delayed setting in the subterranean formation; and providing the setting of the cement composition delayed setting in the subterranean formation. 2. The method according to claim 1, characterized in that the foaming of the delayed setting cement composition includes adding a foaming additive to the delayed setting cement composition and providing gas entrainment into the delayed setting cement composition. 3. The method according to p. 2, characterized in that the foaming additive is selected from the group consisting of: betaine; hydrolyzed keratin; amine oxides; alkyl or alkene dimethyl amine oxide; cocoamidopropyl dimethyl amine oxide; methyl ester sulfonate; alkyl or alkene dimethylamidobetaine; cocoamidopropyl betaine; alpha olefin sulfonate; quaternary surfactant; tall trimethylammonium chloride; trimethyl cocoammonium chloride; C8 to C22 alkyl ethoxylate sulfate; and any combination thereof. 4. The method according to any one of paragraphs. 1-3, characterized in that the foaming of the cement composition of the delayed setting provides a foamed cement composition of the delayed setting, the quality of the foam is from about 5% to about 80%. 5. The method according to p. 1, characterized in that the foaming of the cement delayed setting composition provides a foamed delayed setting cement composition with a density of from about 9 pounds per gallon (about 1.1 kg / l) to about 11 pounds per gallon (about 1 3 kg / l). 6. The method according to p. 1, characterized in that the activation of the foamed delayed setting cement composition includes adding to the delayed setting cement composition a cement setting activator, said cement setting activator comprising at least one activator selected from the group consisting of an amine, silicate, zinc formate, calcium acetate, salts of the monovalent cation, salts of the divalent cation, nanosilica, polyphosphate and any combination thereof. 7. The method according to claim 1, wherein the delayed setting cement composition is injected into the subterranean formation using a method including pumping the delayed setting cement composition through a pipeline, through a casing shoe and into the annulus of the wellbore. 8. The method according to p. 1, in which the ratio of slaked lime to pumice is from about 3: 1 to about 5: 1. 9. The method according to p. 1, in which the ratio of slaked lime to pumice is from about 10: 1 to about 1: 1. 10. The method according to p. 1, in which water is present in the cement composition delayed setting in an amount of from about 33% to about 200% relative to the weight of pumice. 11. The method according to p. 1, in which the dispersing agent is present in an amount of from about 0.01% to about 5% relative to the weight of pumice. 12. The method according to p. 1, in which the activation of the cement composition delayed setting comprises adding to the cement composition a delayed setting activator setting cement in an amount of from about 1% to about 20% relative to the weight of pumice. 13. The method according to claim 1, in which the delayed setting cement composition is further stored for a period of about 1 day or for a longer period until the step of activating the delayed setting cement composition. 14. The method according to claim 1, in which the delayed setting cement composition is further stored for a period of about 7 days or for a longer period prior to the step of activating the delayed setting cement composition. 15. Foamed cement composition delayed setting, containing: water pumice slaked lime a dispersing agent and a setting retarder, wherein the setting retarder contains a phosphonic acid derivative and the dispersing agent is a polycarboxylic acid ester; foaming additive trapped gas. 16. Foamed delayed setting cement composition according to claim 15, containing one or more components defined in paragraph 3. 17. A cementing system comprising: delayed setting cement composition comprising: water pumice slaked lime, and a dispersing agent and a setting retarder, wherein the setting retarder contains a phosphonic acid derivative and the dispersing agent is a polycarboxylic acid ester; a foaming additive for foaming a delayed setting cement composition; gas for foaming a delayed setting cement composition; and cement setting activator for activating a delayed setting cement composition. 18. The system of claim 17, further comprising mixing equipment for mixing the foaming additive, gas, and cement setting agent with delayed setting cement composition and pumping equipment for delivering the cement composition to the wellbore. 19. The system according to p. 17 or 18, characterized in that the foaming additive is selected from the group consisting of: betaine; hydrolyzed keratin; amine oxides; alkyl or alkene dimethyl amine oxide; cocoamidopropyl dimethyl amine oxide; methyl ester sulfonate; alkyl or alkendimethylamidobetaine; cocoamidopropyl betaine; alpha olefin sulfonate; quaternary surfactant; tall trimethylammonium chloride; trimethyl cocoammonium chloride; C8 to C22 alkyl ethoxylate sulfate; and any combination thereof. 20. The system of claim 17, wherein the cement setting activator comprises at least one activator selected from the group consisting of amine, silicate, zinc formate, calcium acetate, monovalent cation salt, divalent cation salt, nanosilica, polyphosphate and any combination of them. 21. The system of claim 17, wherein the delayed setting cement compositions are characterized in that it remains in a fluid state suitable for pumping for at least about 7 days. 22. The system of claim 17, wherein the ratio of slaked lime to pumice is from about 3: 1 to about 5: 1. 23. The system of claim 17, wherein water is present in the delayed setting cement composition in an amount of about 33% to about 200% based on the weight of the pumice stone. 24. The system according to p. 17, characterized in that it contains a mixture of a phosphonic acid derivative with at least one setting retarder selected from the group consisting of phosphonic acid, lignosulfonate, organic acid salt, cellulose derivative, synthetic polymer or triple a polymer containing sulfonate groups and carboxylic acid groups, a borate compound, and combinations thereof. 25. The system of claim 17, further comprising at least one substance selected from the group consisting of a sulfated formaldehyde-based dispersant, a dispersant comprising a polycarboxylic acid ester, and combinations thereof. 26. The system of claim 17, wherein the setting retarder comprises a phosphonic acid derivative, wherein the delayed setting cement composition further comprises a dispersing agent that is a polycarboxylic acid ester. 27. The system of claim 17, wherein the cement setting activator comprises at least one activator selected from the group consisting of amine, silicate, zinc formate, calcium acetate, hydroxide of an element of group IA; hydroxide of an element of the group IIA group, salts of the monovalent cation, salts of the divalent cation, nanosilica, polyphosphate, and any combination thereof.

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