RU2637347C2 - Activators for hardening cement for cement compositions with disabled hardening and related methods - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: method of cementing includes supply of cement compositions with delayed setting that contains water, pumice, hydrated lime and retarder, activation of cement compositions with delayed hardening liquid additive for getting activated cement composition, where liquid supplement contains monovalent salt, polyphosphate, dispersant and water, and where monovalent salt is present in liquid additive in an amount of 0.1% to 30 wt % of the liquid additive. Polyphosphate is present in the liquid additive in an amount of 0.1% to 30 wt % of the liquid additive. The dispersant is present in the liquid additive in an amount of 0.1% to 90 wt % of the liquid additive, and water is present in the liquid additive in an amount of 50% to 90 wt % of the liquid additive; and allowing the activated cement composition to harden. The invention also relates to an activated cement composition comprising water, pumice, hydrated lime, retarder, a liquid additive for activating the activated cement composition, wherein the liquid additive contains monovalent salt, polyphosphate, dispersant and water, and where monovalent salt is present in the liquid additive in an amount of 0.1% to 30 wt % of the liquid additive. Polyphosphate is present in the liquid additive in an amount of 0.1% to 30 wt % of the liquid additive. The dispersant is present in the liquid additive in an amount of 0.1% to 90 wt % of the liquid additive, and water is present in the liquid additive in an amount of 50% to 90 wt % of the liquid additive. The invention also relates to a system for cementing.

EFFECT: increasing the efficiency of the cementing method, including when used in subterranean formations with lower bottom hole temperatures.

19 cl, 4 dwg, 20 tbl

Description

BACKGROUND

[0001] Embodiments of the invention relate to underground cementing operations and, in certain embodiments of the invention, to delayed setting cement compositions and methods for their use in underground formations.

[0002] Cement compositions can be used in many underground operations. For example, in underground well construction, a string of pipes (for example, casing, liners, expandable pipes, etc.) can be lowered into the shaft and cemented in place. The in situ cementing of the pipe string is commonly referred to as “primary cementing”. In the conventional primary cementing method, the cement composition is pumped into the annular space between the walls of the wellbore and the outer surface of the pipe string located inside it. The cement composition may solidify in the annular space, thereby forming an annular shell of hardened, substantially sealed cement (i.e., cement shell), which can support and position the pipe string in the wellbore and can connect the outer surface of the pipe string to the subterranean formation . Among other things, the cement sheath surrounding the pipe string prevents fluid migration in the annulus and protects the pipe string from corrosion. Cement compositions can also be used in repair insulating cementing methods, for example, to seal cracks or holes in pipe columns or cement shells, to seal highly permeable formation zones or cracks, to install cement plugs and the like.

[0003] In underground cementing operations, a wide range of cement compositions is used. In some cases, delayed setting cementitious compositions were used. Delayed setting cementitious compositions have the ability to remain in a pumpable liquid state for at least about one day (e.g., at least about 7 days, about 2 weeks, about 2 years or more) at room temperature (e.g., about 26.7 ° C (80 ° F)) when stationary. If it is necessary to use them, cementitious compositions with delayed setting must be capable of activation, as a result of which the proper compression strength appears. For example, a cement setting accelerator may be added to a delayed setting cement composition by which the composition is set into a hardened mass. Among other things, a delayed setting cement composition may be suitable for laying in a wellbore, for example, when it is desired to prepare the cement composition in advance. This makes it possible, for example, to store the cement composition before use. In addition, this makes it possible, for example, to prepare the cement composition in a suitable place, and then transport it to the place of work. Accordingly, it opens the possibility of reducing capital expenditures by reducing the need for storing raw materials and mixing equipment at the work site. This can be especially useful in offshore cementing operations where space on board ships may be limited.

[0004] Although delayed setting cement compositions have been developed previously, their successful use in underground cementing is problematic. For example, delayed setting cement compositions prepared from Portland cement are prone to undesirable gelation, which may limit their use and effectiveness in cementing operations. Other previously delayed setting compositions, for example, containing hydrated lime and silica sand, may be effective in some operations, but they are of limited use at low temperatures because they may not have sufficient compressive strength when used in underground formations with lower static temperatures at the bottom of the well.

[0001] These graphics illustrate certain aspects of embodiments of the present method, and cannot be used to limit or define the method.

FIG. 1 illustrates a system for preparing and delivering a cementitious composition with delayed setting in a wellbore in accordance with certain embodiments of the invention.

FIG. 2A illustrates surface equipment that can be used to place a delayed setting cement composition in a wellbore in accordance with certain embodiments of the invention.

FIG. 2B illustrates the placement of a cement composition with delayed setting in the annular space of a wellbore in accordance with certain embodiments of the invention.

[0005] FIG. 3 is a graph illustrating the relationship between the amount of dispersant and setting time of delayed setting cement compositions activated with a liquid additive that contains a combination of a monovalent salt and a polyphosphate activator.

DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION

[0006] Embodiments of the invention relate to underground cementing operations and, in certain embodiments of the invention, to delayed setting cement compositions and methods for their use in underground formations. In specific embodiments of the invention, improved cement setting activators that are used to activate delayed setting cement compositions can be provided. Embodiments of the invention of cement setting agents can be used to activate a delayed setting cement composition, while also providing desirable thickening times and compression strength.

[0007] Embodiments of delayed setting cement compositions may generally include water, pumice, slaked lime and setting retarder. Optionally, delayed setting cement compositions may further comprise a dispersant. Embodiments of the invention of delayed setting cement compositions may be foamed. Preferably, embodiments of delayed setting cement compositions of the invention may be able to remain in a state suitable for pumping fluid for extended periods of time. For example, delayed setting cement compositions may remain in a suitable state for pumping fluid for at least about 1 day, about 2 weeks, about 2 years, or longer. Preferably, after activation at relatively low temperatures, delayed setting cement compositions can acquire suitable compression strength. While delayed setting cement compositions may be suitable for many underground cementing operations, they may be especially suitable for use in underground formations with relatively low static temperatures at the bottom of the well, for example, temperatures lower than about 93.4 ° C (200 ° F) or ranging from about 37.8 ° C (100 ° F) to about 93.4 ° C (200 ° F). In alternative embodiments of the invention, delayed setting cement compositions can be used in subterranean formations with static downhole temperatures up to 232.3 ° C (450 ° F) or higher.

[0008] Water that is used in embodiments of delayed setting cement compositions can be taken from any source, provided that it does not contain an excess of compounds that may undesirably affect other components in delayed setting cement compositions. For example, a delayed setting cement composition may contain fresh water or salt water. In general, salt water may contain one or more dissolved salts and may be saturated or unsaturated, depending on what is required in a particular application. In embodiments of the invention, seawater or brine from a well may be used. In addition, water may be present in an amount sufficient to form a slurry pulp suitable for pumping. In certain embodiments of the invention, water may be present in the cementitious composition with a delayed setting in an amount that is in the range from about 33% to about 200% by weight of pumice. In certain embodiments of the invention, water may be present in the cementitious composition with a delayed setting in an amount that is in the range from about 35% to about 70% by weight of pumice. Using this description, an ordinary specialist can determine the right amount of water for the selected application.

[0009] Embodiments of the delayed setting cement compositions may include pumice. In general, pumice is a volcanic rock that can exhibit cementing properties in the sense that it can set and solidify in the presence of hydrated lime and water. Pumice stone may also be ground. In general, a pumice stone may have any particle size distribution that is required for specific applications. In certain embodiments of the invention, pumice may have an average particle size in the range of from about 1 micrometer to about 200 micrometers. The average particle size corresponds to d50 values measured by particle size analyzers, such as those made by Malvern Instruments, Worcestershire, United Kingdom. In specific embodiments of the invention, pumice may have an average particle size in the range of from about 1 micrometer to about 200 micrometers, from about 5 micrometers to about 100 micrometers, or from about 10 micrometers to about 50 micrometers. In one specific embodiment, the pumice stone may have an average particle size of less than about 15 micrometers. An example of a suitable pumice stone is a product sold by Hess Pumice Products, Inc., Malad, Idaho, under the name "DS-325 Lightweight Aggregate" having a particle size of less than about 15 micrometers. It should be noted that using particles of too small sizes can create problems with miscibility, while particles of too large sizes are difficult to effectively suspend in the compositions. Using this description, ordinary specialists are able to choose a particle size such that the pumice stone is suitable for the selected application.

[0010] Embodiments of the delayed setting cement compositions may comprise hydrated lime. In this document, the term "slaked lime" means calcium hydroxide. In some embodiments, slaked lime may be supplied as quicklime (calcium oxide), which hydrates when mixed with water to form slaked lime. Slaked lime may be contained in embodiments of the invention of cementitious compositions with delayed setting, for example, for the formation of slurries with pumice. For example, hydrated lime can be included in a mass ratio of pumice to hydrated lime from about 10: 1 to about 1: 1 or from 3: 1 to about 5: 1. If hydrated lime is present, it can be included in delayed setting cement compositions. in an amount, for example, from a range of from about 10% to about 100% by weight of pumice. In some embodiments of the invention, slaked lime may be present in an amount that is between any of the ratios to the mass of pumice from about 10%, about 20%, about 40%, about 60%, about 80%, or about 100% and / or includes any of them. In some embodiments of the invention, the cementitious components that are present in the cementitious composition with a delayed setting may consist essentially of pumice and slaked lime. For example, astringent components can mainly contain pumice and slaked lime without any additional components (e.g. Portland cement, fly ash, slag cement), which set in the presence of water. Using this description, an ordinary specialist can determine the appropriate amount of slaked lime for inclusion in the selected application.

[0011] Embodiments of the delayed setting cement compositions may include a setting retarder. A wide range of setting retarders is suitable for use in delayed setting cement compositions. For example, the set retarder may contain phosphonic acids such as ethylenediamine tetra (methylenephosphonic acid), diethylene triamine penta (methylenephosphonic acid), etc .; lignosulfonates such as sodium lignosulfonate, calcium lignosulfonate, etc .; salts such as tin sulfate, lead acetate, monocalcium phosphate, organic acids such as citric acid, tartaric acid, etc .; cellulose derivatives such as hydroxyl ethyl cellulose (HEC) and carboxyl methyl hydroxyl ethyl cellulose (SMNES); synthetic co- or terpolymers containing sulfonate groups or carboxylic acid groups, such as copolymers of sulfonate-substituted acrylamide-acrylic acid; borate compounds such as alkali borate compounds, sodium metaborate, sodium tetraborate, potassium pentaborate; derivatives or mixtures thereof. Examples of suitable setting retarders include, but are not limited to, phosphonic acid derivatives. One example of a suitable set retarder is the Micro Matrix ^® set retarder, available from Halliburton Energy Services, Inc. In general, a setting retarder may be present in cementitious compositions with delayed setting in an amount sufficient to delay the hardening by the desired time. In some embodiments, the setting retarder may be present in delayed setting cement compositions in an amount from the range of about 0.01% to about 10% by weight of pumice stone. In specific embodiments of the invention, the setting retarder may be present in an amount that is between any of the ratios to the mass of pumice from about 0.01%, about 0.1%, about 1%, about 2%, about 4%, about 6% , about 8% or about 10% and / or includes any of them. An ordinary person skilled in the art can, using this description, determine the appropriate amount of setting retarder for administration to the selected application.

[0012] As indicated previously, embodiments of delayed setting cement compositions may optionally comprise a dispersant. Examples of suitable dispersants include, but are not limited to, dispersants based on sulfonated formaldehyde (e.g., the sulfonated condensation atsetonformaldegida), examples of which may include a dispersant Daxad ^® 19, available from Geo Specialty Chemicals, Ambler, Pennsylvania. Other suitable dispersants may be based dispersants ether polycarboxylate such as Liquiment ^® 558IF and Liquiment ^® 514L, supplied by BASF Corporation Houston, Texas; or Ethacryl ^™ G Dispersant, available from Coatex, Genay, France. A further example of suitable dispersants commercially available is CFR ^™ -3, available from Halliburton Energy Services, Inc, Houston, Texas. Dispersant Liquiment ^® 514L may comprise 36% by weight of a polycarboxylate ether in water. Although various dispersants may be used in accordance with embodiments of the invention, in some embodiments polycarboxylated ether dispersants may be particularly suitable. Without reference to theory, it can be argued that dispersants based on polycarboxylated ether can synergistically interact with other components of the cement composition with a delayed setting. For example, it can be argued that dispersants based on polycarboxylated ether can react with certain retarders (e.g., derivatives of phosphonic acid), which leads to the formation of a gel that suspends pumice and slaked lime in the composition for a long period of time.

[0013] In some embodiments, the dispersant may be contained in delayed setting cement compositions in an amount from the range of about 0.01% to about 5% by weight of pumice. In specific embodiments of the invention, the dispersant may be present in an amount that is between any of the ratios to the mass of pumice from about 0.01%, about 0.1%, about 0.5%, about 1%, about 2%, about 3 %, about 4% or about 5% by weight of pumice and / or includes any of them. An ordinary person skilled in the art can, using this description, determine the appropriate amount of dispersant for administration to the selected application.

[0014] Other additives suitable for use in underground cementing operations may also be contained in delayed setting cement compositions. Examples of such additives include, but are not limited to: weighting additives, lightweight additives, gas generating additives, mechanical additives, absorption control materials, filtration control additives, fluid loss reducers, defoaming agents, blowing agents, thixotropic additives, and combinations thereof . In embodiments of the invention, one or more of these additives may be incorporated into the delayed setting cement compositions after storage, but before the delayed setting cement composition is placed in the subterranean formation. Using this description, an ordinary specialist can easily determine the type and amount of additives that will be useful for a particular application and achieve the desired result.

[0015] It will be understood by those of ordinary skill in the art that embodiments of delayed setting cement compositions should generally have a density suitable for particular applications. For example, delayed setting cement compositions may have a density ranging from about 0.47934 tons per cubic meter (t / m ³ ) (4 pounds per gallon (“lb / gallon”)) to about 2.397 t / m ³ (20 lb / gall). In certain embodiments of the invention, delayed setting cement compositions may have a density in the range of from about 095.86 t / m ³ (8 lb / gall) to about 2,037 t / m ³ (17 lb / gall). Embodiments of the delayed setting cement compositions may be foamed or non-foamed, or may contain other means to reduce their densities, such as hollow microspheres, low density elastic beads, or others known in the art to reduce the density of the additive. In embodiments of the invention, one or more of these additives may be incorporated into the delayed setting cement compositions after storage, but before the delayed setting cement composition is placed in the subterranean formation. Using this description, ordinary specialists can determine the appropriate density for a particular application.

[0016] As indicated previously, delayed setting cement compositions may be in a delayed setting state in which they remain in a form suitable for pumping fluid for at least one day (eg, at least about 1 day, about 2 weeks) , about 2 years or more) at room temperature (for example, about 26.7 ° C (80 ° F)) when stored at rest. For example, delayed setting cement compositions may remain in a condition suitable for pumping fluid for periods of time from about 1 day to about 7 days or more. In some embodiments of the invention, delayed setting cement compositions may remain in a state suitable for pumping fluid for at least about 1 day, about 7 days, about 10 days, about 20 days, about 30 days, about 40 days, about 50 days, about 60 days or longer. It is believed that the fluid is in a condition suitable for pumping if its consistency is less than 70 Verdun consistency units (“Vs”) when measured with a pressure gauge for pressure measurements using the method for determining cement thickening times described in API RP Practice 10B-2, Recommended Practice for Testing Well Cements, First Edition, July 2005.

[0017] If it is necessary to use embodiments of the invention of cementitious compositions with delayed setting, the compositions can be activated (for example, combining them with an activator) to turn into a hardened mass. It is accepted herein that the term “cement setting activator” or “activator” refers to an additive that activates cement compositions with a delayed or very slow setting time and can also accelerate the curing of these or other cement compositions. For example, embodiments of delayed setting cementitious compositions can be activated to turn into a hardened mass over time periods ranging from about 1 hour to about 12 hours. For example, embodiments of delayed setting cement compositions can set with the formation of a hardened mass for periods of time that are between any of about 1 day, about 2 days, about 4 days, about 6 days, about 8 days, about 10 days or about 12 days and / or includes any of these terms.

[0018] In some embodiments of the invention, delayed setting cement compositions after activation can set and acquire the desired compression strength. In general, compression strength is the ability of a material or structure to withstand axial thrust. Compression strength can be measured at a given point in time after activation of the cement composition with a delayed setting, when the resulting composition is at a given temperature and pressure. Compression strength can be measured by destructive or non-destructive methods. When using the destructive method, physical testing of the strength of the samples of the composition for processing the trunk zone at various points in time is performed in a test press. Compression strength is calculated by dividing the breaking load by the cross-sectional area to which it is applied and measured in Bars (units of pound force per square inch (psi)). Non-destructive methods may include the use of an ultrasonic cement analyzer UCA ^™ , which is supplied by Farm Instrument Company, Houston, TX. Compressive strength values can be determined in accordance with API Guide RP 10B-2, Recommended Practice for Testing Well Cements, First Edition, July 2005.

[0019] For example, delayed setting cement compositions can acquire compression strength in 24 hours from a range of from about 3.45 bar (50 psi) to about 344.74 bar (5000 psi), alternatively, from about 6.9 bar ( 100 psi) to about 310.27 Bars (4,500 psi), or alternatively from about 34.48 Bars (500 psi) to about 275.8 Bars (4000 psi). In some embodiments of the invention, delayed setting cement compositions can acquire a compression strength of at least about 3.45 Bars (50 psi), at least about 6.9 Bars (100 psi), at least about 34, in 24 hours. 48 Bar (500 psi) or more. In some embodiments of the invention, the values of compression strength can be determined using destructive or non-destructive methods in the temperature range from 37.8 ° C (100 ° F) to 93.4 ° C (200 ° F).

[0020] In some embodiments of the invention, delayed setting cement compositions may have predetermined thickening times after activation. The thickening time usually refers to the period of time during which the composition, such as a cement composition with a delayed setting, remains in a liquid state suitable for pumping. Many different laboratory techniques can be used to measure thickening times. To measure the suitability for pumping a composition for processing near-barrel areas, you can use a pressure gauge for pressure measurements, following the method described in the above API RP Practice 10B-2 manual. The thickening time may be the period that the composition needs to process the trunk zones to reach 70 Bs, and may be referred to as the time to reach 70 Bs. In some embodiments of the invention, cementitious compositions may have a thickening time of more than about 1 hour, alternatively more than about 2 hours, alternatively more than about 5 hours at 206.85 bar (3000 psi) and temperatures in the range of about 10 ° C. (50 ° F) to about 204.5 ° C (400 ° F), alternatively, in the range of about 26.7 ° C (80 ° F) to about 121.2 ° C (250 ° F) and alternatively at temperature about 60 ° C (140 ° F).

[0021] Embodiments of the invention may include the addition of a cement setting activator to delayed setting cement compositions. Examples of suitable cement setting activators include, but are not limited to: zeolites, amines such as triethanolamine, diethanolamine; silicates such as sodium silicate; zinc formate; calcium acetate; Group IA and IIA metal hydroxides, such as sodium hydroxide, magnesium hydroxide and calcium hydroxide; monovalent salts, such as sodium chloride; divalent salts 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 of the invention, a combination of polyphosphate and a monovalent salt may be used for activation. The monovalent salt may be any salt that dissociates to form a monovalent cation, such as sodium and potassium salts. Specific examples of suitable monovalent salts include potassium sulfate and sodium sulfate. To activate delayed setting cement compositions, in combination with a monovalent salt, a wide range of different polyphosphates can be used, including polymeric metaphosphate salts, phosphate salts, and combinations thereof. Specific examples of suitable metaphosphate salts 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 of the invention, the activator may be prepared and added to the delayed setting cement composition in the form of a liquid additive, for example, a liquid additive containing a monovalent salt, polyphosphate and, optionally, a dispersant.

[0022] Some embodiments of the invention may include a cement setting agent containing nanosilica. It is accepted herein that the term "nanosilica" refers to silica with a particle size of less than or equal to about 100 nanometers ("nm"). The particle size of nanosilica can be measured using any suitable technique. It should be understood that the measured particle size of nanosilica may vary depending on the measurement technique, sample preparation and conditions such as temperature, concentration, etc. One of the methods for measuring the particle size of nanosilica is transmission electron microscopy (TEM). An example of a commercially available instrument that uses laser diffraction is a ZETASIZER Nano ZS particle size analyzer, available from Malvern Instruments, Worcestershire, UK. In some embodiments of the invention, the silica fume may comprise colloidal silica fume. Nanosilica can be stabilized using any suitable technique. In some embodiments of the invention, silica fume can be stabilized with a metal oxide such as lithium oxide, sodium oxide, potassium oxide, and / or a combination thereof. In addition, nanosilica can be stabilized with an amine and / or metal oxide, as described above. Embodiments of the invention with nanosilica have an additional advantage due to the fact that these materials are known to fill the pore space in cements, which can lead to improved mechanical properties of the cement after hardening.

[0023] Some embodiments of the invention may include a cement setting agent containing a combination of monovalent salt and polyphosphate. Monovalent salt and polyphosphate can be combined before adding to the delayed setting cement composition, or they can be added separately to the delayed setting cement composition. The monovalent salt may be any salt that dissociates to form a monovalent cation, such as sodium and potassium salts. Specific examples of suitable monovalent salts include potassium sulfate and sodium sulfate. To activate delayed setting cement compositions, a wide variety of different polyphosphates can be used in combination with a monovalent salt, including, for example, polymer metaphosphate salts, phosphate salts, and combinations thereof. Specific examples of suitable metaphosphate salts 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. It is curious that sodium hexametaphosphate is known in the industry as a powerful moderator of Portland cements. Due to their unique chemistry, polyphosphates can be used as a cement setting agent for the delayed setting cement compositions disclosed herein. The ratio of monovalent salt to polyphosphate may be in the range of, for example, from about 5: 1 to about 1:25 or from about 1: 1 to about 1:10. Embodiments of the cement setting activator may comprise a monovalent salt and a polyphosphate salt in relation to ( monovalent salt to polyphosphate), which is between any of and / or includes any of the ratios of about 5: 1, 2: 1, about 1: 1, about 1: 2, about 1: 5, about 1:10, about 1: 20 or about 1:25.

[0024] In some embodiments of the invention, the combination of a monovalent salt and polyphosphate may be mixed with a dispersant and water to form a liquid additive to activate the delayed setting cement composition. Examples of suitable dispersants include, but are not limited to, the previously described dispersants, such as sulfonated formaldehyde based dispersants and polycarboxylated ether based dispersants. One example of a suitable dispersant based on a sulfonated formaldehyde is a sulfonated acetone-formaldehyde condensate available from Halliburton Energy Services, Inc., as CFR - 3 ^™. One example of a suitable dispersant on the basis of a polycarboxylate ether dispersants represents Liquiment ^® 514L or 5581F, supplied by BASF Corporation, Houston, Texas.

[0025] The fluid additive may act as a cement setting activator. As described above, the cement setting activator can also accelerate the curing of cement with delayed setting or severely retarded cement. The use of a liquid additive to accelerate delayed setting cement or highly delayed cement depends on the composition of the liquid additive, as well as the component composition of delayed setting cement or very slow cement. Using this description, an ordinary specialist is able to develop a formulation of a liquid additive to activate and / or accelerate cement with delayed setting or a very slowed down cement composition.

[0026] The composition of the fluid additive is a delicate balance that correlates with the particular component composition of the delayed setting cement composition. The amount of monovalent salt and polyphosphate must be carefully balanced in relation to the dispersant. A liquid additive with the wrong mixture of components can lead to the creation of a cement composition with a delayed setting with far from optimal rheological properties. In some embodiments of the invention, the fluid additive may be added to the delayed setting cement composition in an amount of from about 1% to about 20% by weight of the cement composition, and, alternatively, from about 1% to about 10% by weight of the cement composition.

[0027] The monovalent salt may be present in the liquid additive in an amount of from about 0.1% to about 30% by weight of the liquid additive. In specific embodiments of the invention, the polyphosphate may be present in an amount that is between any of and / or includes any of the ratio to the weight of the liquid additive from about 0.1%, about 1.0%, about 10%, or about 30%. Using this description, an ordinary specialist is able to calculate the composition of a liquid additive with a sufficient amount of polyphosphate for a specific application.

[0028] The polyphosphate may be present in the liquid additive in an amount of from about 0.1% to about 30% by weight of the liquid additive. In specific embodiments of the invention, the polyphosphate may be present in an amount that is between any of and / or includes any of the ratio to the weight of the liquid additive from about 0.1%, about 1.0%, or about 30%. Using this description, an ordinary specialist is able to calculate the composition of a liquid additive with a sufficient amount of polyphosphate for a specific application.

[0029] The dispersant may be present in the liquid additive in an amount of from about 0.1% to about 90% by weight of the liquid additive. In specific embodiments of the invention, the dispersant may be present in an amount that is between any of the ratios to the weight of the liquid additive of about 0.1%, about 1%, about 50%, or about 90%. Using this description, an ordinary specialist is able to calculate the composition of a liquid additive with a sufficient amount of dispersant for a specific application.

[0030] Water may be present in the liquid additive in an amount of from about 50% to about 90% by weight of the liquid additive. In specific embodiments of the invention, water may be present in an amount that is between any of and / or includes any of the ratio to the weight of the liquid additive from about 50%, about 60%, about 75%, or about 90%. Using this description, an ordinary specialist has the opportunity to calculate the composition of a liquid additive with enough water for a specific application.

[0031] In accordance with embodiments of the invention, the ratio of the components of the fluid additive may be related to the component composition of the delayed setting cement composition. For this reason, the amounts of monovalent salt, polyphosphate, and dispersant are functions of the amounts of lime, pumice, and the total amount of water (i.e., water in the delayed setting cement composition and any water in the fluid additive) that are used in the activated cement composition.

[0032] Without being bound by theory, it can be argued that the main limitations in the formulation of the liquid additive are the solubility limits of the monovalent salt and polyphosphate, as well as the amount of dispersant required to produce cement with acceptable rheological properties. Solubility limits are inherently inherent in the selected monovalent salt and polyphosphate, and therefore cannot be changed; on the other hand, the amount of dispersant is associated with the amounts of monovalent salt and polyphosphate. The amounts of monovalent salt / polyphosphate and dispersant are in a pseudo-direct relationship, therefore, in a balanced composition, an increase in the amount of one of these components requires, to maintain the balance of the composition, an increase in the number of others. For example, if the amounts of monovalent salt and polyphosphate are increased, then the amount of dispersant must also be increased, otherwise the cement composition will be too thick to pump. Conversely, if the amount of dispersant is increased, the cement composition will be too liquid, and solid particles may precipitate from the solution until the amounts of monovalent salt and polyphosphate are also increased.

[0033] In some embodiments of the invention, the fluid additive should provide a thickening time in the wellbore conditions of more than about 1 hour, alternatively, more than about 2 hours, alternatively more than about 5 hours. In some embodiments of the invention, the fluid additive should provide a thickening time in the conditions of the wellbore from about four to about six hours. As described above, the thickening time usually refers to the time during which the fluid, such as the cement composition, remains in a liquid state suitable for pumping. The liquid additive affects the rheological properties of the cement composition. Therefore, a liquid additive can affect the pumping time of cement. If the rheological properties of the cement are not optimal, the activated cement composition may be too thick or too liquid, and therefore may not be suitable for pumping at the right time.

[0034] In some embodiments of the invention, the fluid additive may impart delayed setting cement or highly retarded cement to the desired mechanical properties within 24 hours. Desired 24-hour mechanical properties include compression strengths greater than 17.24 bar (250 psi), uniform density (i.e., no precipitation) and the absence of any free fluid.

[0035] Without being bound by theory, a description is made of the activation mechanism of a delayed setting cement containing lime and pumice using a delayed setting cement activator containing a combination of sodium sulfate and sodium hexametaphosphate. It is believed that sodium sulfate is converted to sodium hydroxide during the reaction with lime. As a result of this reaction, the pH of the cement slurry rises and, therefore, the dissolution rate of silicon dioxide increases. The rate of cement hydration is directly related to the fraction of free silicates and / or aluminosilicates. Sodium hexametaphosphate forms chelating compounds and increases the rate of dissolution of calcium hydroxide. The combination of sodium sulfate and sodium hexametaphosphate creates synergy in various delayed setting cement compositions, which provides better results than the separate use of both cement setting activators.

[0036] A cement setting activator can be added to embodiments of the delayed setting cement composition in an amount sufficient to initiate the conversion of the delayed setting cement composition to a hardened mass. In certain embodiments of the invention, the cement setting agent may be added to the delayed setting cement composition in an amount from the range of about 0.1% to about 20% by weight of pumice stone. In specific embodiments of the invention, the cement setting agent may be present in an amount that is between any of and / or includes any of the ratios to pumice weight of about 0.1%, about 1%, 5%, about 10%, about 15% or about 20%. Using this description, one of ordinary skill in the art can determine the appropriate amount of cement setting agent for administration to a selected application.

[0037] It will be understood by those of ordinary skill in the art that embodiments of delayed setting cement compositions can be used in a variety of underground operations, including primary and repair cementing. In some embodiments of the invention, a delayed setting cement composition is provided that comprises water, pumice, slaked lime, setting retarder, and optionally a dispersant. Delayed setting cementitious composition can be introduced into the underground formation and allowed to solidify there. It is understood herein that the introduction of a delayed setting cement composition into an underground formation includes the introduction into any part of the underground formation, including, but not limited to, the wellbore drilled in the underground formation, the near-wellbore area surrounding the wellbore, or both. Embodiments of the invention may further include delayed setting cement composition activation. Activation of the delayed setting cement composition may include, for example, adding a cement setting activator to the delayed setting cement composition.

[0038] In some embodiments of the invention, a delayed setting cement composition is provided that comprises water, pumice, slaked lime, setting retarder, and optionally a dispersant. Delayed setting cementitious composition can be stored, for example, in a tank or other suitable container. Delayed setting cementitious composition can be left in storage for the desired period of time. For example, a delayed setting cement composition may remain in storage for about 1 day or longer. For example, a delayed setting cement composition may remain in storage for 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 or longer. In some embodiments of the invention, the delayed setting cement composition may remain in storage for a period of time ranging from about 1 day to about 7 days or longer. After this, the delayed setting cement composition can be activated, for example, by adding a cement setting activator, introduced into the underground formation and allowed to solidify there.

[0039] In primary cementing, embodiments of the invention, for example, embodiments of the delayed setting cement composition, can be introduced into the annular space between the casing located in the wellbore and the walls of the wellbore (and / or a larger casing in the wellbore ), where the wellbore passes through the underground formation. Delayed setting cementitious compositions can be allowed to solidify in an annular space to form an annular shell of hardened cement. Delayed setting cementitious composition can form a barrier that prevents fluid migration in the wellbore. Delayed setting cementitious composition may also, for example, support the casing in the wellbore.

[0040] In repair cementing, embodiments of the cementitious composition with delayed setting can be used, for example, in repair insulating work or in the placement of cement plugs. For example, a delayed setting composition can be injected into a wellbore to close an opening (e.g., a void or a crack) in a formation, in gravel packing, in a casing, in a cement sheath and / or between a cement sheath and a casing (e.g., a micro-gap between casing and cement stone).

[0041] An embodiment of the invention includes a cementing method comprising: supplying a delayed setting cement composition comprising water, pumice, slaked lime and setting retarder; activation of the cement composition with a delayed setting of the liquid additive to obtain an activated cement composition, where the liquid additive contains a monovalent salt, polyphosphate, dispersant and water; and allowing solidification of the activated cement composition.

[0042] An embodiment of the invention includes an activated cement composition that comprises: water; pumice; slaked lime; setting retarder; monovalent salt; and polyphosphate.

[0043] An embodiment of the invention includes a cementing system comprising: a delayed setting cement composition, which comprises: water, pumice, slaked lime and setting retarder; and a liquid additive for activating a delayed setting cement composition, which contains: water, a monovalent salt, a polyphosphate and a dispersant.

[0044] Now, with reference to FIG. 1, the preparation of a delayed setting cement composition in accordance with an example embodiment of the invention will be described. FIG. 1 illustrates a system 2 for preparing a cement composition with delayed setting and its subsequent delivery to the wellbore in accordance with certain embodiments of the invention. As shown in the figure, the delayed setting cement composition can be mixed in mixing equipment 4, such as, for example, a jet mixer, a recirculation mixer, a batch mixer, and then pumped into the wellbore using pump equipment 6. In some embodiments of the invention, the mixing equipment 4 and pumping equipment 6 can be placed on one or more cement trucks, which should be clear to ordinary specialists in this field. In some embodiments of the invention, the jet mixer can be used, for example, to continuously mix lime / hardening material with water as the mixture is pumped into the wellbore. In delayed setting embodiments, a recirculation mixer and / or batch mixer can be used to mix the cement composition with the delayed setting, and the activator can be added to the mixer in powder form before pumping the cement composition into the wellbore. In addition, units such as a batch mixer for grout can be installed in line with a reservoir containing a cement setting activator. In this case, the cement setting activator can be supplied simultaneously with the cement slurry when it is pumped out of the mixing unit.

[0045] An example of apparatus for introducing a delayed setting cement composition into an underground formation will be described with reference to FIG. 2A and 2B. FIG. 2A illustrates ground equipment 10 that can be used to hold a delayed setting cement composition in accordance with certain embodiments of the invention. It should be noted that although FIG. 2A generally depicts a surface work site, it should be apparent to those skilled in the art that the principles described herein are equally applicable to subsea operations that use floating or offshore platforms and rigs, without departing from the scope of this description of the invention . As shown in FIG. 2A, ground equipment 10 may include a cementing unit 12, which may contain one or more cement trucks. The cementing unit 12 may contain mixing equipment 4 and pumping equipment 6 (for example, FIG. 1) which should be clear to ordinary specialists. The cementing unit 12 can pump the cementitious composition with a delayed setting 14 through the feed pipe 16 to the cementing head 18, which transfers the cementitious composition with a delayed setting 14 into the well.

[0046] FIG. 2B shows that a delayed setting cement composition 14 can be placed in an underground formation 20 in accordance with an example embodiment of the invention. As illustrated, wellbore 22 may be drilled into subterranean formation 20. Although wellbore 22 is shown extending generally vertically into subterranean formation 20, the principles described herein also apply to wellbores that pass through subterranean formation 20 at an angle such as horizontal and deviated wellbores. As illustrated, wellbore 22 includes walls 24. In the illustrated embodiment, a casing string 26 is inserted into the wellbore 22. The casing string 26 may be cemented to the walls 24 of the wellbore 22 with a cement sheath 28. In the illustrated embodiment, one or more additional casing pipes (e.g., intermediate casing, production casing, liners, etc.) shown here to to the casing 30. As illustrated, in the borehole there is an annular space 32 between the casing 30 and the walls 24 of the borehole 22 and / or the casing string 26. One or more centralizers 34 may be attached to the casing 30, for example, to center the casing columns 30 in the wellbore 22 before and during the cementing operation.

[0047] FIG. 2B shows that the cementitious composition with delayed setting 14 can be pumped down into the casing 30. The cementitious composition with delayed setting 14 can be allowed to flow down inside the casing 30 and through the shoe of the casing 42 at the bottom of the casing 30 rise up around the casing 30 into the annular space 32 of the wellbore. Delayed setting cement composition 14 can be allowed to solidify in the annular space of wellbore 32, for example, to form a cement sheath that supports and positions the casing 30 in wellbore 22. Although not illustrated, it is possible to introduce delayed setting cementitious composition 14 use other equipment. For example, you can use the reverse circulation system, which includes the introduction of a cement composition with a delayed setting 14 in the underground formation 20 not through the casing 30, but through the annular space of the wellbore 32.

[0048] After administration, the delayed setting cement composition 14 may 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 annular space of the wellbore 32. At least a portion of the displaced fluids 36 may exit the annular space of the wellbore 32 via flow line 38 and be deposited, for example, in one or more sumps 40 (eg, in a mud tank), as shown in FIG. 2A. As shown in FIG. 2B, a lower cementing plug 44 may be inserted into the wellbore 22 before the cementitious composition with delayed setting 14, for example, to separate the cemented composition with delayed setting 14 from the fluids 36 that may be inside the casing 30 prior to cementing. After the lower cementing plug 44 reaches the sleeve 46, the diaphragm or other suitable device must open to allow the delayed setting cement composition 14 to pass through the lower cementing plug 44. In FIG. 2B, the lower cementing plug 44 is shown on the sleeve with a stop 46. In the illustrated embodiment, the squeezing plug 48 can be inserted into the wellbore 22 after the delayed setting cement composition 14. The dislodging plug 48 can separate the delayed setting cement composition 14 from the displacement fluid 50, as well as pushing the cement composition with delayed setting 14 through the lower cement plug 44.

[0049] The delayed setting cement compositions described herein as an example may directly or indirectly affect one or more components or parts of equipment related to the preparation, delivery, return, recycling, reuse and / or disposal of the disclosed cement compositions with delayed setting. For example, the delayed setting cementitious compositions described can directly or indirectly affect one or more mixers, associated mixing equipment, drilling fluid reservoirs, storage facilities or blocks, composition separators, heat exchangers, sensors, meters, pumps, compressors, etc. .P. equipment that is used to generate, store, monitor, regulate and / or restore the previous properties of the exemplary cementitious compositions with delayed setting. The delayed setting cement compositions described above can also directly or indirectly affect any transport or delivery equipment that is used to transport delayed setting cement compositions to the well site or delivering them to the well, such as, for example, any transportation containers, nozzles, pipelines, trucks, pipe systems and / or casing used for the composite movement of cement compositions with delayed setting from one place to another, any pumps, comp quarrels or motors (for example, on upper structures or in a well) that are used to drive delayed setting cement compositions, any valves or similar connections that are used to control the pressure or flow rate of delayed setting cement compositions and any sensors (t .e., pressure and temperature), measuring instruments and / or combinations thereof, etc. The delayed setting cementitious compositions described can also directly or indirectly affect various downhole equipment and tools that may come into contact with them, such as, but not limited to, the wellbore casing, the wellbore liner, the completion string, the drill string, technological tool, clutchless long pipe, cable rope, auxiliary rope, tubular rod, drill pipe, hydraulic downhole motors, submersible motors and / and and pumps, cementing pumps, surface mounted motors and / or pumps, centralizers, turbulators, scrapers, check valves (e.g. shoe pipes, adapter couplings, valves, etc.), logging devices and associated telemetry equipment, control mechanisms valves (for example, electromechanical devices, hydromechanical devices, etc.), sliding couplings, outlet pipes, plugs, strainers, filters, flow control devices (for example, flow regulators, autonomous regulators inflow, outflow regulators, etc.), coupler connections (e.g. electro-hydraulic wet connection, dry connection, inductive coupler, etc.), control lines (e.g. electrical, fiber optic, hydraulic, etc.) , observation lines, drill bits and borehole reamers, sensors or distributed sensors, immersion heat exchangers, valves and associated control mechanisms, tool seals, packers, cement plugs, bridge plugs and other insulating devices or components of the well bore azhiny, etc.

[0050] In order to improve understanding of the present embodiments of the invention, the following examples of specific aspects of certain embodiments of the invention are provided. These examples should in no way be taken as limiting or defining the full scope of the embodiments of the invention.

EXAMPLES

Example 1

[0051] The following example describes an example of the composition of a liquid additive intended for use with the delayed setting cement composition as an example. In this example, a fluid additive was added to the cementitious composition with a delayed setting in the amount of 8% of the total mass of slaked lime and pumice. After activation, the delayed setting activated cement composition had a thickening time of 5.5 hours at 37.8 ° C (100 ° F). Thickening time was measured using a pressure consistency meter at 37.8 ° C (100 ° F) in accordance with the method for determining cement thickening times described in API RP Practice 10 B-2, Recommended Practice for Testing Well Cements, First Edition, July 2005. As discussed above, varying the concentration of dispersant without adjusting the amounts of monovalent salt and polyphosphate to compensate for these changes can lead to less than optimal rheology of the cement slurry and change the thickening time.

[0052] An example of a delayed setting cement composition comprises water; DS-325 pumice lightweight aggregate available from Hess Pumice Products, Inc., Malad, Idaho; slaked lime; Dispersant Liquiment 558IF ^®, available from BASF Corporation, Houston, Texas; cement setting retarder and Micro Matrix ^® (MMCR), available from Halliburton Energy Services, Inc., Duncan, Oklahoma. The component composition is shown in Table 1 below. The amounts listed in Table 1 are shown as percent by weight of the pumice stone.

[0053] An example of a liquid additive contained water, a monovalent salt (sodium sulfate), a polyphosphate (sodium hexametaphosphate) and a dispersant Liquiment 558IF ^®. The component composition is presented in the following Table 2. The listed amounts are shown as a percentage of the total composition of the liquid additive.

Example 2

[0054] In this example, a batch of six samples of a liquid additive was prepared for use with an example of a delayed setting cement composition. The composition of the delayed setting cement composition is presented below in Table 3. In Table 3, “% bwP” means “percent by weight of pumice” and “gal / sk” means “gallon per pumice bag weighing 20.87 kg (46 lbs."). The liquid additive comprises water, a monovalent salt (sodium sulfate), a polyphosphate (sodium hexametaphosphate), and a dispersant Liquiment 5581F ^®. The amounts of water, monovalent salt and polyphosphate were kept constant, as shown below in Table 4. The concentration of dispersant was different for each of the six samples, as shown below in Table 5. The fluid additive from Table 4 was added to the cement composition with a delayed setting from Table 3 so so that the mass of the fluid additive is equal to 10% of the total weight of the cementitious composition with delayed setting and the fluid additive.

[0055] The amount of dispersant was varied in the range from 0.00% to 4.3%. The rheology of cement slurries also varied depending on the amount of dispersant present, since the amounts of monovalent salt and polyphosphate were kept constant. Recall that the amount of dispersant is presented as a percentage of the total weight of the activated composition. After preparation, the rheological properties of the samples were determined using Model 35A Farm Viscometer and No. 2 Farm Yield Stress Adapter devices, in accordance with the method described in API RP Practice 10B-2, Recommended Practice for Testing Well Cements. The data are presented in Table 5 below. The rheological data shown in Table 5 are apparent viscosity values measured at a shear rate of 100 (1 / s).

[0056] Example 2 illustrates that changing the amount of dispersant without adjusting the amounts of monovalent salt and polyphosphate to compensate for these changes can lead to the creation of cement mortars with less than optimal rheological characteristics.

[0057] A sample of cement slurry 1 from Table 5 was unusable and non-flowing. For the remaining 5 samples of cement mortar, Archimedes tests were carried out. For Archimedes tests, each of the samples was loaded into 5.08 cm × 10.16 cm (2`` × 4 '') cylinders and allowed to solidify for 24 hours at 60 ° C (140 ° F). Then, the hardened samples were cut into three equally spaced parts along the length of the cylinders. According to the Archimedes principle for density and displacement, we determined the density of the samples and expressed them in units of t / m (lb / gall). The results are presented below in Table 6.

[0058] Samples 2-5 showed no significant problems with precipitation. Sample 6 precipitated. In general, the more dispersant is added, the less viscous the cement slurry becomes. Sample 5 showed the best characteristics of the cement mortar, and represents the best choice compared to the other 5 according to the results of this criterion alone. Other cement mortars can potentially be optimal when factors such as cost and early occurrence of mechanical strength are considered.

Example 3

[0059] The cement slurry composition shown in Table 3 above was used as an example of a delayed setting cement composition. An example of the composition of the liquid additive, however, differs from that presented in Table 4. Table 7 shows the new composition of the liquid additive, specifically for this example.

[0060] Table 8 shows the different values for the dispersant described in Table 7. Four different amounts of dispersant were used. The concentration of dispersant is a percentage of the total mass of activated cement. The amount of dispersant is in the range from 0.0% to 4.3%. After preparation, the rheological properties of the samples were determined using Model 35A Farm Viscometer and No. 2 Farm Yield Stress Adapter devices, in accordance with the method described in API RP Practice 10B-2, Recommended Practice for Testing Well Cements. The data are presented in Table 8 below. The rheological data shown in Table 8 are apparent viscosity values measured at a shear rate of 100 (1 / s).

[0061] Archimedes tests were conducted for 4 cement slurry samples. To conduct Archimedes tests, each of the samples was cut into three equally spaced parts. According to the principle of Archimedes density and displacement determined density of samples and expressed in terms of t / m ³ (lb / gal). The results are presented below in Table 9.

[0062] Significant precipitation was observed in Samples 9 and 10, in which there were 0.68% and 4.3% dispersant, respectively. Compared to Example 2, this indicates that a decrease in the amount of liquid additive added to the sample can also lead to a change in the optimal concentration of dispersant in the liquid additive. In this case, the optimal concentration of the dispersant was 0.45%, whereas in the previous Examples it was 2.4%.

Example 4

[0063] In this Example, the cement slurry described in Table 3 was used as the base composition. The composition of the liquid additive is presented below in Table 10. Sodium sulfate was used as the monovalent salt. As polyphosphate, sodium hexametaphosphate was used. As a dispersant, Coatex 1702, supplied by Coatex Inc., Chester, South Carolina, was used. As shown in Table 11, the concentration of dispersant was varied in the range from 0.45% to 8.33%.

[0064] To determine the effect of changes in dispersant concentration on the compressive strength of hardened samples, the compressive strength of each sample was measured after five days. To measure the compressive stress, the samples were placed for hardening in 2 ”by 4” plastic cylinders, which were placed in a water bath at 87.8 ° C (190 ° F) to form hardened cylinders. Immediately after removal from the water bath, the destructive compressive forces were determined using a mechanical press, in accordance with the method described in API RP 10B-2, Recommended Practice for Testing Well Cements. The results of this testing are presented below in Table 12 in Bars (psi units). The compressive forces given are the average of the data for the two cylinders of each sample.

[0065] Changes in the concentration of dispersant had a direct effect on the compressive strength of the samples. This effect was stronger than the precipitation caused by the addition of a dispersant. Thus, it is obvious that the dispersant can have an antagonistic effect on the activation of sodium hexametaphosphate cement mortar with an extended solidification period, if the slowdown was carried out by phosphonate nitrilotrismethylene triphosphonic acid.

[0066] Archimedes tests were conducted for Samples 1-5. Each of the samples was loaded into 5.08 cm × 10.16 cm (2`` × 4 '') cylinders and allowed to harden for five days at 60 ° C (140 ° F). Then, the hardened samples were cut into three equally spaced parts along the length of the cylinders. According to the Archimedes principle for density and displacement, the densities of the samples were determined and recorded. The results are presented below in Tables 13-17, where the abbreviation PPG refers to units of pound / gallon.

[0067] Samples 4 and 5 showed a slight precipitation.

Example 5

[0068] In this example, ten samples of a liquid additive were prepared for use with a delayed setting cement composition. The component composition of the delayed setting cement composition is shown in Table 18 below. The fluid additive contained water, a monovalent salt in the form of sodium sulfate, polyphosphate in the form of sodium hexametaphosphate, and Liquiment 558IF ^® dispersant. It should be noted that the percentages of the monovalent salt and polyphoeophate were kept constant during the experiment, while the concentration of the dispersant was changed. The composition of the liquid additive is presented below in Table 19. All of the listed amounts are shown as a percentage of the total composition of the liquid additive. The fluid additive of Table 19 was added to the delayed setting cement composition from Table 18 so that the monovalent salt and polyphosphate were present in a total amount of 1.25% bwP or 1.00% bwP.

[0069] The amount of dispersant was varied in the range from 0.10% to 1.39%. The thickening time of cement mortars varied depending on the amount of dispersant present, since the amounts of monovalent salt and polyphosphate were kept constant.

[0070] Compression strength and thickening times of each sample were measured. To measure the compressive stress, the samples were placed for hardening in 2 ”by 4” plastic cylinders, which were placed in a water bath at 87.8 ° C (190 ° F) to form hardened cylinders. Immediately after removal from the water bath, the destructive compressive forces were determined using a mechanical press, in accordance with the method described in API RP 10B-2, Recommended Practice for Testing Well Cements. The results of this test are presented below in Table 20. The compressive forces given are the average of the data for the three cylinders of each sample.

[0071] the Change in the concentration of dispersant in the liquid additive made it possible to control the thickening time of the cement composition with a delayed setting. This additional advantage was realized as a result of the observation that the thickening time of cement samples increased with increasing amount of dispersant. For liquid additive samples containing 1.25% bwP of the monovalent polyphosphate salt, the dependence was almost linear, as shown in FIG. 3.

[0072] It should be understood that the compositions and methods are described in the context of "content", "containment" or "inclusion" of the various components or steps, in addition, the compositions and methods may "consist mainly of" or "consist of" various components and stages. In addition, the singular form used in the claims assumes the presence of one or more of the elements in question.

[0073] For brevity, only certain ranges are fully disclosed herein. However, ranges from any lower limit can be combined with any upper limit to describe a range not described in full, just as ranges from any lower limit can be combined with any other lower limit to describe a range not described in full. in the same way, ranges from any upper limit can be combined with any other upper limit to describe a range not fully described. In addition, in all cases where a numerical range with a lower limit and an upper limit is disclosed, any number and any included range falling within this range are specifically described. In particular, each range of values (in the form of “from about a to about b” or, equivalently, “from about a to b” or, equivalently, “from about a-b”) described herein should be understood as describing each number and range included in a wider range of values, even if they are not fully described. Thus, each point or individual value can act as its own lower or upper limit, combined with any other point or individual value, or with any other lower or upper limit, to describe a range that is not fully described.

[0074] Thus, the present invention is excellent for achieving the objectives and obtaining the advantages mentioned above, as well as its inherent. The specific embodiments of the invention disclosed above are merely illustrative, since the present disclosure of embodiments of the invention can be modified and implemented in various, but equivalent ways, obvious to experts in this field who have the opportunity to familiarize themselves with the present description. Although only individual embodiments of the invention were discussed, this description provides for and encompasses any combination of each embodiment of the invention. In addition, there are no restrictions on the details of the development or design described in this document, except as described in the following claims. Also, the terms in the claims are used in their simple, ordinary meaning, unless otherwise expressly indicated by the applicant. Thus, it is obvious that the specific illustrative embodiments of the invention disclosed above can be modified or modified, while all such changes are within the scope and essence of the present invention. If there is a contradiction in the use of a word or term in the present description and one or more patent (s) or other documents that may be incorporated into this description by reference, the definitions corresponding to the present description should be adopted.

Claims (40)

 1. The method of cementing, including: the delayed setting cement composition containing water, pumice, slaked lime and setting retarder; activation of the cement composition with a delayed setting of the liquid additive to obtain an activated cement composition, where the liquid additive contains a monovalent salt, polyphosphate, dispersant and water, and where the monovalent salt is present in the liquid additive in an amount of from 0.1% to 30% by weight of the liquid additive, moreover, polyphosphate is present in the liquid additive in an amount of from 0.1% to 30% by weight of the liquid additive, while the dispersant is present in the liquid additive in an amount of from 0.1% to 90% by weight of the liquid additive, and water is present in the liquid additive in an amount of from 50% to 90% by weight of the liquid admixture; and enabling the activated cement composition to harden. 2. The method according to p. 1, characterized in that the liquid additive is added to the cement composition with a delayed setting in an amount of from 1% to 20% by weight of the cement composition with a delayed setting. 3. The method according to p. 1, characterized in that the polyphosphate contains sodium hexametaphosphate. 4. The method according to p. 1, characterized in that the monovalent salt contains sodium sulfate. 5. The method according to p. 1, characterized in that the dispersant contains polycarboxylated ether. 6. The method according to p. 1, characterized in that the ratio of the monovalent salt to polyphosphate is from 5: 1 to 1:25. 7. The method according to p. 1, characterized in that the polyphosphate contains sodium hexametaphosphate, the monovalent salt contains sodium sulfate, and the dispersant contains polycarboxylated ether. 8. The method according to p. 1, characterized in that the cement composition with delayed setting remains in a condition suitable for pumping liquid for a period of time from 4 hours to 6 hours after activation. 9. The method according to claim 1, further comprising storing the cement composition with delayed setting for 1 day or longer. 10. The method of claim 1, further comprising introducing the activated cement composition into the subterranean formation. 11. The method according to claim 1, further comprising pumping the activated cement composition through the casing, through the shoe of the casing and into the annular space of the wellbore. 12. Activated cement composition containing: water pumice stone slaked lime; setting retarder; a liquid additive for activating an activated cement composition, wherein the liquid additive contains a monovalent salt, a polyphosphate, a dispersant and water, and where the monovalent salt is present in the liquid additive in an amount of 0.1% to 30% by weight of the liquid additive, wherein the polyphosphate is present in the liquid additive in the amount of from 0.1% to 30% by weight of the liquid additive, while the dispersant is present in the liquid additive in the amount of from 0.1% to 90% by weight of the liquid additive and the water is present in the liquid additive in the amount of 50% to 90 % by weight of liquid additives. 13. The activated cement composition according to claim 12, containing one or more elements defined in any one of paragraphs. 3-7. 14. A cementing system comprising: delayed setting cement composition comprising: water pumice slaked lime and setting retarder; and a liquid additive for activating a cement composition with a delayed setting, containing: water monovalent salt polyphosphate and dispersant, where the monovalent salt is present in the liquid additive in an amount of from 0.1% to 30% by weight of the liquid additive, and polyphosphate is present in the liquid additive in an amount of from 0.1% to 30% by weight of the liquid additive, while the dispersant is present in the liquid additive in an amount of from 0.1% to 90% by weight of the liquid additive and wherein water is present in the liquid additive in an amount of from 50% to 90% by weight of the liquid additive. 15. The cementing system according to p. 14, characterized in that the ratio of monovalent salt to polyphosphate is from 5: 1 to 1:25. 16. The cementing system according to claim 14 or 15, characterized in that the polyphosphate contains sodium hexametaphosphate. 17. The cementing system according to p. 14, characterized in that the monovalent salt contains sodium sulfate, and the dispersant contains polycarboxylated ether. 18. The cementing system according to claim 14 or 15, characterized in that the polyphosphate contains sodium hexametaphosphate, the monovalent salt contains sodium sulfate and the dispersant contains polycarboxylated ether. 19. A cementing system according to claim 14, further comprising: mixing equipment for mixing a delayed setting cement composition and a liquid additive to obtain a delayed setting cement composition; and pumping equipment for the delivery of cement compositions with delayed setting in the wellbore.

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