CN103146369A - Novel chemical foamed cement slurry and construction process thereof - Google Patents
Novel chemical foamed cement slurry and construction process thereof Download PDFInfo
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- CN103146369A CN103146369A CN2013100820148A CN201310082014A CN103146369A CN 103146369 A CN103146369 A CN 103146369A CN 2013100820148 A CN2013100820148 A CN 2013100820148A CN 201310082014 A CN201310082014 A CN 201310082014A CN 103146369 A CN103146369 A CN 103146369A
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Abstract
The invention discloses novel chemical foamed cement slurry and a construction process thereof. The novel chemical foamed cement slurry comprises cement, floating bead, waters, a foamed cement foaming agent FCA, a foamed cement foaming agent FCB, a stabilizer FCP, a retarder FCR and a foam stabilizer FCF. The construction process comprises the following steps of: step 1. taking the foamed cement foaming agent FCA, the stabilizer FCP, the floating bead and the retarder FCR in proportion and uniformly dry-mixing into cement; step 2. pouring the foamed cement foaming agent FCB and the foam stabilizer FCF into a water tank of a cement truck in which a foaming agent is injected before construction, adding water till reaching the designed injection volume and agitating for uniformly mixing; and finally, mixing the two mixtures into a well through a pipeline truck or a tee, so that the foaming agent enters the well to form the foamed cement slurry while reacting in a pipe. The novel chemical foamed cement slurry and the construction process thereof have the beneficial effects that inside bubbles are uniformly distributed, are independent of one another, are not communicated with one another and are spherical; and the novel chemical foamed cement slurry is stable in structure and high in strength, and the performances of strength and permeability of the novel foamed cement are superior to the performance indexes of foreign foamed cement.
Description
Technical field
The present invention relates to the cement slurry cementing technical field, is new chemical foam slurry and construction technique thereof concretely.
Background technology
Oil field light weight cement commonly used is divided into four kinds: the first is to add a high proportion of mixing water, and controls free water, is generally to add the solid-state inorganics of viscosity or lightweight filling agent, as removes soil, diatomite, oil base milk sap and perlite etc.; The second is to add light material, particularly organic materials in grout, resembles nut-shell, coke, gilsonite etc.; The third is to add tiny withstand voltage hollow glass ball or Ceramic Balls; The 4th kind is aerated foam cement slurries.
The all widespread uses of front two kinds of methods concerning most wells, are both economical methods, but these two kinds of methods all can only make density be down to 1.32～1.44 g/cm
3, for the lower situation of density requirements, for example the responsive weak zone of abnormal pressure, be difficult to satisfy intensity and infiltrative requirement, in most cases only is used for the neck slurry.The third cement slurry density can be lower than 1.32g/cm
3, the ability that grout is controlled leakage is improved, but bears pressure when larger, and the hollow microsphere in slurry can seepage make variable density larger.And the cost of this grout is also high, is 4～10 times of general low-density cement mortar, and application is restricted.
On the basis of the third light weight cement, people have done again further research and exploration.1975, U.S. Aldrish and Mitchll proposed directly to inflate in grout, namely reach as light-weight additive with gas and fall low-density purpose.1978, the people such as U.S. S.Yamada test also successfully produced the oil well foamed cement for the first time.First Application in 1979, effect is fine.The eighties, the cementing technology of foamed cement have had very great development.People have improved frothing machine, and strict option table surface-active agent is as suds-stabilizing agent, make gas with the form stable dispersion of even bubble disconnected from each other in whole system, produce the foam slurry of excellent property.
Physics inflation (air or N are adopted in the preparation of foamed cement usually
2) method and chemical agent inflation process.Foamed cement mainly has following characteristics: 1, density is low, intensity is high; 2, low permeability; 3, low dehydration; 4, suitable thixotropy; 5, low heat conductivity; 6, anti-channeling.
Foamed cement is through years of researches and application, development and perfect.Especially mechanical aeration (N
2Or air) method is used widely abroad, but this method required equipment is more, and complex process needs well-designed and computer controlled automatic, and difficulty and expense are higher.
Summary of the invention
Purpose of the present invention is exactly the defective that exists for prior art, provides a kind of well cementation effective, and density is low, intensity is high, low permeability, low dehydration, low heat conductivity and the good new chemical foam slurry of anti-channeling.
Another technical problem to be solved by this invention is to provide a kind of construction technique for preparing above-mentioned new chemical foam slurry.
Its technical scheme is: the new chemical foam slurry comprises each component of following weight proportion:
Cement 30%-70% floats pearl 10%-40%, water 50%-88%, foamed cement foaming agent FCA1.0%-2.5%, foamed cement foaming agent FCB0.1%-1.0%, suds-stabilizing agent FCF2%-4%, stablizer FCP1.0%-3%, retarder FCR 0.5%-1.4%.
Wherein the optimum weight proportioning is: cement 20%, float pearl 20.6%, water 50%, foamed cement foaming agent FCA2%, foamed cement foaming agent FCB1.0%, suds-stabilizing agent FCF2%, stablizer FCP3%, retarder FCR 1.4%.
Described foam slurry also comprises water retaining.
The construction technique of new chemical foam slurry is: the one tunnel get in proportion foamed cement foaming agent FCA, stablizer FCP, float pearl and retarder FCR evenly is dry mixed in cement; Before another road construction, foamed cement foaming agent FCB and suds-stabilizing agent FCF are poured in the water tank of annotating the foaming agent cementing truck, and add water to the design total injection, stirring mixes it; At last two-way is mixed into well after piping converges car or threeway, foaming agent enters in inner reaction tube and forms foam slurry in well like this.
After having adopted technique scheme, the beneficial effect that the present invention obtains is: because the foamed cement foaming agent FCA of novel foam cement evenly is dry mixed in cement in advance, the efficient steady bubble effect of suds-stabilizing agent FCF in addition, its inside configuration bubble distribution is even, separate, be not communicated with, and be spherical, Stability Analysis of Structures, the enhancement of the stability of novel foam cement structures and stablizer FCP, the higher major cause of its intensity, so the performance of the intensity of novel foam cement and rate of permeation is better than the performance index of external foamed cement.Under the curing condition that even the present invention is lower in temperature, the time is shorter, can improve intensity.The new chemical foam slurry is to react in grout by whipping agent to generate N
2, by suds-stabilizing agent trap gas, form mutual disconnected foamed cement slurry system, be applicable to the well cementation of general low pressure and easy leaking stratum, water-sensitive strata, thermal recovery well and anti-gas channeling well.
Embodiment
The invention will be further described below in conjunction with embodiment.
Embodiment one:
The new chemical foam slurry comprises each component of following weight proportion:
Cement 30% floats pearl 10%, water 55.4%, foamed cement foaming agent FCA1.0%, foamed cement foaming agent FCB0.1%, suds-stabilizing agent FCF2%, stablizer FCP1.0%, retarder FCR 0.5%.
Described foam slurry also comprises water retaining.Can make grout play the good leak-off, anti-gas channeling, toughness reinforcing etc. of falling by water retaining.
(1) compounding method of additive: foamed cement foaming agent FCA, toughener are stablizer FCP, float pearl and retarder FCR evenly is dry mixed by a certain percentage in cement, well in entrucking; Before construction, foamed cement foaming agent FCB, suds-stabilizing agent FCF are poured in the water tank of annotating the foaming agent cementing truck, and add water to the design total injection, stir and make its mixing.
(2) construction technique: foamed cement foaming agent FCA, FCB and water immediate response generate nitrogen, thus can not be as the common cementing practice, and for fear of the impact of bubble on Shang Shui and lower grey speed, working procedure can be divided into two portions.One tunnel cementing is as breaking plain cement; Foaming agent is annotated on another road, contains foamed cement foaming agent FCB and suds-stabilizing agent FCF, is mixed into well after two-way process manifold truck or threeway, and foaming agent enters in inner reaction tube and forms foam slurry in well like this.In order to test the foamed cement pulp density, can connect a bypass pipe sampling at well head.
(3) parameter is controlled on ground: the construction technology technology of foamed cement except different with general cementing operation, also is the control of ground injection rate.It controls parameter:
1. annotate plain cement density
Density in order to ensure foamed cement reaches design requirements, at first must control basic pulp density well.General density difference does not surpass 0.03 g/cm
3
2. annotate the foaming agent discharge capacity
Owing to containing foaming agent FCB and suds-stabilizing agent FCF in foaming agent, so the displacement size of foaming agent is directly connected to the size of foamed cement gas forming amount, that is the size of foamed cement density, and the size of water cement ratio.Discharge capacity is too small, and the density that enters the well foamed cement is bigger than normal: discharge capacity is excessive, and water cement ratio is bigger than normal, affects intensity.Therefore, the control of the total amount of injection foaming agent liquid and discharge capacity is most important.Foaming agent total amount of liquid size is calculated according to following formula:
Inject foaming agent total amount of liquid=cement total amount * (foamed cement the total water-cement ratio-cement based pulp-water gray scale)
Inject the size of foaming agent liquid displacement, available following formula calculates:
The foaming agent total amount
Foaming agent discharge capacity=------* cementing discharge capacity
The grout total amount
(4) performance index:
Surface water mud density: 0.68～1.35 g/cm
3
Underground cement pulp density: 1.20～1.55 g/cm
3
Ultimate compression strength: 3～20 MPa
In (30 ~ 105 ℃) the lower thickening time: 100～300min is adjustable
Initial consistency :≤25 Bc
Free liquid content: 0～1.5 ml
Novel foam cement is through desk research, experimental result shows: the intensity of novel foam cement and the performance of rate of permeation are better than the performance index of external foamed cement, this is that foaming agent FCA due to novel foam cement evenly is dry mixed in cement in advance, the efficient steady bubble effect of FCF in addition, its inside configuration bubble distribution is even, separate, is not communicated with, and be spherical, constitutionally stable cause.
The stability of novel foam cement structures and the enhancement of FCP are the higher major causes of its intensity.3-8 can find out from table, even under the curing condition lower in temperature, that the time is shorter, intensity has still improved 36%.
Table 3-8 novel foam cement and the contrast of mechanical aeration foamed cement ultimate compression strength
The rate of permeation of novel foam cement depends primarily on the performance of suds-stabilizing agent.FCF suds-stabilizing agent better performances owing to newly developing makes the rate of permeation of foamed cement very low.Under borehole condition, almost suitable with the conventional density plain cement.
1, the application of foamed cement slurry system in oil well
ⅰ, effect
From year June in June, 1994 to 1998, in long celebrating Huachi, this floating bead low-density foamed cement of the Oilfield using slurry system such as Jingan County, Zhenyuan altogether sealing 132 mouthfuls of oil wells, qualification rate of cementing 100%, the factor of merit 80.3% has solved the difficult problem of the long interval isolation of above-mentioned oil field low pressure and easy leaking substantially.
ⅱ, analyzing of applying effects
Analyze from effect and sealing quality (logging trace), adopt the mortar architecture of this extremely-low density, substantially can satisfy and return high request, and YAN ' AN FORMATION top comprises that the sealing quality of river, Lip river layer is also comparatively desirable, reason is:
A, mixed slurry section are short.During well cementation, the mixed slurry of grout and spacer pad, drilling fluid is completed in sleeve pipe mostly.Because cement slurry density is low especially.Thereby and spacer pad, drilling fluid between density difference very little, therefore short being inevitable of mixed slurry section.
B, displacement efficiency are high, and consolidation strength is good.Because this low-density cement mortar is the foam slurry that a kind of chemistry fills nitrogen, be a kind of compressible cement, to talk about by sentence, this grout has good elasticity.Therefore, in displacement process, because the expansion of grout is much bigger to the more conventional low-density cement mortar of the displacement efficiency of mud, in addition, after replacement put in place, the consolidation strength of Behavior of Hardened Cement Paste also can be therefore and better.
C, the anti-performance of altering are good.In condensing process, this chemistry fills the nitrogen low-density cement mortar, and its internal gas pressure can make up the problem that bottomhole wellbore pressure that cement slurry weight loss causes descends fully, is conducive to prevent that oil, gas, water breakthrough are on the impact of cement mantle sealing quality.
2, the application of foamed cement slurry system in gas well
For checking the effect of the floating bead low-density foam slurry of developing, to solve the cementing quality problem of the long interval isolation of the sweet peaceful Central Gas Fields low pressure and easy leaking in Shan, at first on carrying out once, Shan203Jing returning the well cementation test.Shan 203 wells 13 " dark 502.50 meters of bit drills, 10 " 502.23 meters of casing setting depths; 9 " bit drills is dark 2985 meters, and 7 " casing setting depth 2980m. gas-bearing formation mainly is distributed in the stratum such as Taiyuan, Shanxi (2881m) (2936m), Benxi (2965m).The equivalent on top Liu family ditch (2144m) stratum density of breaking only has 1.25g/cm
3, completion mud density 1.11g/cm
3, viscosity 60s, dehydration 7ml, mud cake 0.5mm, the pH value is 11, the hole diameter amplification degree is 12%.Adopt a sealing of the full well of floating bead low-density foam slurry.In construction process, there is no leakage phenomena, the 48h well logging, superior in quality.
After Shan203Jing uses this extremely-low density grout to return well cementation on once to achieve success, successively apply at 13 implication wells such as Shan205Jing, Shan207Jing again, all obtain good effect, qualification rate of cementing reaches 100%, and the factor of merit reaches 84.5%.
Hence one can see that, adds the extremely-low density grout that floats pearl and foaming agent, although its density more only adds the grout that floats pearl much smaller, its cement strength is but high than the latter.This shows, this extremely-low density grout not only has wider density use range, also has the Behavior of Hardened Cement Paste ultimate compression strength high than other light weight cement.Have good over-all properties to float pearl cement as the foam slurry of base slurry, particularly having higher intensity under lower density is that other light weight cements are inaccessiable.
3, conclusion and understanding
(1) extremely-low density grout of the present invention is the combination that chemical method fills nitrogen and floating bead low-density cement mortar, the characteristic that not only has floating bead low-density cement mortar, the favorable elasticity that also has foam slurry more is conducive to improve the cementing of displacement efficiency and cement mantle first and second interface.
(2) extremely-low density grout of the present invention has the characteristics such as the density use range is wide, intensity is high, stability is good.
(3) adopt this extremely-low density grout, not only can satisfy the stratum to the requirement of the performances such as cement slurry density, but also can return well shaft fixing technology on using once, replace the two-stage cementing method that the long interval isolation well of low pressure and easy leaking adopts usually, for saving sizing collar and work time cost in the oil field, have larger economy and technical meaning to reducing brill completion total cost.
Embodiment two:
Cement 20% floats pearl 20.6%, water 50%, foamed cement foaming agent FCA2%, foamed cement foaming agent FCB1.0%, suds-stabilizing agent FCF2%, stablizer FCP3%, retarder FCR 1.4%.
Other and embodiment one are basic identical, do not repeat them here.
Case brief introduction: the 36-8-XX of Soviet Union well
This well 216mm bit drills is to 3462m, and 139.7mm casing setting depth 3460m, distribution of gas reservoir adopt and just annotating anti-extruding process well cementation at 3326～3435m.Just the section of notes 2320-3462m, adopt two solidifying dual density mortar architecture, wherein tail slurry density 1.90 g/cm
3, use foamed cement to starch to press steady anti-channeling, density 1.75 g/cm as neck
3, use the low fluid-loss cement slurry system.Cementing operation is smooth, well logging result demonstration one, the cementing high-quality of second interface, qualification rate 100%, the factor of merit 90%.
Certainly, the present invention is not limited to above-mentioned embodiment, and in a word, those skilled in the art is from above-mentioned enlightenment, within other replacement form of expecting all belongs to protection scope of the present invention.
Claims (4)
1. new chemical foam slurry is characterized in that: each component that comprises following weight proportion:
Cement 30%-70% floats pearl 10%-40%, water 50%-88%, foamed cement foaming agent FCA1.0%-2.5%, foamed cement foaming agent FCB0.1%-1.0%, suds-stabilizing agent FCF2%-4%, stablizer FCP1.0%-3%, retarder FCR 0.5%-1.4%.
2. new chemical foam slurry according to claim 1, it is characterized in that: wherein the optimum weight proportioning is: cement 20%, float pearl 20.6%, water 50%, foamed cement foaming agent FCA2%, foamed cement foaming agent FCB1.0%, suds-stabilizing agent FCF2%, stablizer FCP3%, retarder FCR 1.4%.
3. new chemical foam slurry according to claim 1 and 2, it is characterized in that: described foam slurry also comprises water retaining.
4. the construction technique of new chemical foam slurry according to claim 1 is characterized in that: the one tunnel get in proportion foamed cement foaming agent FCA, stablizer FCP, float pearl and retarder FCR evenly is dry mixed in cement; Before another road construction, foamed cement foaming agent FCB and suds-stabilizing agent FCF are poured in the water tank of annotating the foaming agent cementing truck, and add water to the design total injection, stirring mixes it; At last two-way is mixed into well after piping converges car or threeway, foaming agent enters in inner reaction tube and forms foam slurry in well like this.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104946220A (en) * | 2015-06-12 | 2015-09-30 | 天津中油渤星工程科技有限公司 | Early strength foam cement slurry for well cementation |
| CN105019859A (en) * | 2015-08-20 | 2015-11-04 | 中国海洋石油总公司 | Pressure stabilizing technology capable of improving well cementing quality of high-temperature and high-pressure well |
| CN103525387B (en) * | 2013-09-29 | 2016-01-20 | 中国石油大学(华东) | Foamed cement slurry system and composition |
| CN105545247A (en) * | 2015-12-08 | 2016-05-04 | 中国石油天然气股份有限公司 | Well cementing method for oil and gas well |
| WO2017135951A1 (en) * | 2016-02-04 | 2017-08-10 | Halliburton Energy Services, Inc. | Food grade material as effective clay control agent |
| CN109517589A (en) * | 2017-09-19 | 2019-03-26 | 中国石油化工股份有限公司 | A kind of oil gas well cementing operation dry method light-weight cement slurry and preparation method |
| CN112048290A (en) * | 2020-10-21 | 2020-12-08 | 陕西延长石油（集团）有限责任公司 | Acidic nano foaming agent for high-salinity formation water of low-permeability oil and gas field and preparation method and application thereof |
-
2013
- 2013-03-14 CN CN2013100820148A patent/CN103146369A/en active Pending
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Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103525387B (en) * | 2013-09-29 | 2016-01-20 | 中国石油大学(华东) | Foamed cement slurry system and composition |
| CN104946220A (en) * | 2015-06-12 | 2015-09-30 | 天津中油渤星工程科技有限公司 | Early strength foam cement slurry for well cementation |
| CN104946220B (en) * | 2015-06-12 | 2018-05-25 | 天津中油渤星工程科技有限公司 | A kind of early strong foam slurry of well cementation |
| CN105019859A (en) * | 2015-08-20 | 2015-11-04 | 中国海洋石油总公司 | Pressure stabilizing technology capable of improving well cementing quality of high-temperature and high-pressure well |
| CN105019859B (en) * | 2015-08-20 | 2017-07-28 | 中国海洋石油总公司 | Improve the steady technique of pressure of hp-ht well cementing quality |
| CN105545247A (en) * | 2015-12-08 | 2016-05-04 | 中国石油天然气股份有限公司 | Well cementing method for oil and gas well |
| CN105545247B (en) * | 2015-12-08 | 2018-08-10 | 中国石油天然气股份有限公司 | A kind of oil gas well cementing operation method |
| WO2017135951A1 (en) * | 2016-02-04 | 2017-08-10 | Halliburton Energy Services, Inc. | Food grade material as effective clay control agent |
| CN109517589A (en) * | 2017-09-19 | 2019-03-26 | 中国石油化工股份有限公司 | A kind of oil gas well cementing operation dry method light-weight cement slurry and preparation method |
| CN112048290A (en) * | 2020-10-21 | 2020-12-08 | 陕西延长石油（集团）有限责任公司 | Acidic nano foaming agent for high-salinity formation water of low-permeability oil and gas field and preparation method and application thereof |
| CN112048290B (en) * | 2020-10-21 | 2023-02-28 | 陕西延长石油（集团）有限责任公司 | Acidic nano foaming agent for high-salinity formation water of low-permeability oil and gas field and preparation method and application thereof |
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Application publication date: 20130612 |