CN108359427A - A kind of ocean gas hydrate stratum Compositional type drilling fluid - Google Patents
A kind of ocean gas hydrate stratum Compositional type drilling fluid Download PDFInfo
- Publication number
- CN108359427A CN108359427A CN201810262424.3A CN201810262424A CN108359427A CN 108359427 A CN108359427 A CN 108359427A CN 201810262424 A CN201810262424 A CN 201810262424A CN 108359427 A CN108359427 A CN 108359427A
- Authority
- CN
- China
- Prior art keywords
- drilling fluid
- mass ratio
- drilling
- hydrate
- gas hydrate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/02—Well-drilling compositions
- C09K8/04—Aqueous well-drilling compositions
- C09K8/06—Clay-free compositions
- C09K8/12—Clay-free compositions containing synthetic organic macromolecular compounds or their precursors
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
Abstract
A kind of ocean gas hydrate stratum Compositional type drilling fluid, is related to exploitation of gas hydrates field.Drilling fluid of the present invention includes following components:Sodium metasilicate, sodium chloride, methanol, ethylene glycol, low viscosity carboxymethyl cellulose LV CMC, polyacrylic acid potassium, xanthans, Vinylcaprolactam homopolymer, propylene glycol phenylate, tetra-n-butyl ammonium phosphate and preparation water, it can be used for ocean gas hydrate storage drilling well to use, has the function of Solid Free, low temperature resistant, it is compounded with synergist in drilling fluid by the way that kinetic inhibitor is added, inhibition is generated with stronger hydrate, and components of drilling liquid is small to environmental hazard, has many advantages, such as that efficient, environmental protection, raw material are cheap and easy to get.
Description
Technical field
The present invention relates to a kind of ocean gas hydrate stratum Compositional type drilling fluids, and in particular to gas hydrates are opened
Adopt field.
Background technology
Gas hydrates in nature are mainly distributed on epeiric ocean deepwater area and land permafrost area, preceding
Person accounts for oneself and finds the overwhelming majority of quantity.Gas hydrates are one of very promising alternative energy sources, to gas hydrates
Research be contemporary geoscience and energy industry developmental research a big hot spot.Submarine sedimentary strata, which is contained, a large amount of natural gas
Hydrate will be explored and be developed to the gas hydrates for assigning the plant certain depths in underground, and drilling well is essential heavy
Want means.The phase equilibrium properties of gas hydrates determine that such strata drilling and general hydrocarbon formations drilling well have very very much not
Together, this kind of strata drilling is also caused to face more complicated well inner question, at present the main problem of gas hydrates drilling fluid
There is the following:
(1) when being crept into natural gas hydrate stratum, since reservoir stress can discharge near the reservoir borehole wall and shaft bottom, stratum
Pressure reduction;And the friction of bit cutting rock, bottomhole and the borehole wall and rock core can all generate a large amount of thermal energy, make hydration
The temperature, pressure condition that object is stabilized is destroyed;To cause the decomposition of hydrate, borehole well instability is caused, drillng operation is made
At adverse effect.
(2) decomposition of mud filtrate invasion and hydrate can cause formation pore pressure to increase in various degree, pore pressure
Increase so that drilling fluid density needed for wellbore stability is kept also accordingly to increase, this not only seriously affects drilling speed, but also increases the borehole wall
Infiltration, makes the pore pressure in well week increase, and to further decrease the stability of the borehole wall, forms vicious circle.
(3) due to entering the water that decomposition of hydrate generates in drilling fluid filtrate and stratum in stratum in drilling process,
Stratum water content is caused gradually to increase.When stratum water content is excessively high, hydrate formation skeleton aquation can be made to aggravate, lead to the borehole wall
It is more unstable.Also, decomposition of hydrate can also be such that the permeability on stratum increases, and drilling fluid is permeated to the borehole wall generates osmotic pressure,
The caving pressure on stratum is set to improve, fracture pressure reduces, and makes the borehole wall be more easy to cave in and pressure break, reduces borehole wall stability.
(4) sea bed gas hydrate is stored, gas hydrates are stored in drilling process, the decomposition of hydrate
The super quiet pore pressure in the storage soil body is set to increase rapidly, so as to cause submarine landslide or foundation of sea floor unstability, in turn
It may cause the destruction of the facilities such as drilling, drilling platforms, submarine pipeline.
Chinese patent literature publication number CN103146364B, patent name are《A kind of high inhibition water-base drilling fluid》, by water
100 parts, 0.2-4 parts of polyamine inhibitor, 0.1-1 parts of inhibitor of coating, 10-25 parts of hydrate inhibitor, 0.1-1 parts of tackifier,
0.5-3 parts of compositions of 0.5-5 parts of fluid loss additive and fluid lubricant.The drilling fluid can inhibit deep water shallow stratum borehole well instability, can
The generation for solving the problems, such as hydrate in deepwater drilling is applicable in the drillng operation of the 3000m depth of waters.Chinese patent literature discloses
Number CN104531106A, patent name are《A kind of efficient hydrate inhibition environmental protection drilling fluid》, by water, bentonite, quaternary amine
Type Gemini surface active agent, inorganic salts, sodium carboxymethyl starch, cationic polyacrylamide, solid anti sinking lubricant GFRH compositions,
The petroleum resources exploitation that can be used for land or ocean, effectively inhibits the generation of hydrate, and components of drilling liquid is to environmental hazard
It is small, have many advantages, such as efficient, environmental protection.Chinese patent literature publication number CN105018052A, patent name are《A kind of low solid phase is low
Warm polymer drilling fluid》, including basal liquid and inorganic agent, wherein basal liquid are answered with sodium bentonite and sodium chloride solution
Match;Inorganic agent is that sulfonated bodies cation exchange resin is compounded with polysaccharide as flow pattern regulator.The drilling fluid is in low temperature
Under the conditions of to decompose strong inhibition capability, good rheological property, fluid loss low.Above-mentioned drilling fluid has one to gas hydrates storage drilling well
Fixed effect, but do not consider to use Compositional type hydrate inhibitor.
Ensure that natural gas hydrate stratum drilling safety successfully carries out, must just take measures to well temperature and pressure
Power is strictly controlled, and controls and reduce the degree of decomposition of hydrate as far as possible using the drilling fluid with good low temperature properties,
To keep wellbore stability and shaft safety, therefore on the basis of the above, the present invention proposes a kind of ocean gas hydrate stratum
Compositional type drilling fluid.
Invention content
The purpose of the present invention is to provide a kind of ocean gas hydrate stratum Compositional type drilling fluid, drilling fluids of the present invention
Including following components:Sodium metasilicate, sodium chloride, methanol, ethylene glycol, low viscosity carboxymethyl cellulose LV-CMC, polyacrylic acid potassium, Huang
Virgin rubber, Vinylcaprolactam homopolymer, propylene glycol phenylate, tetra-n-butyl ammonium phosphate and preparation water, can be used for marine natural air water
It closes object storage drilling well to use, has the function of Solid Free, low temperature resistant, pass through addition kinetic inhibitor and synergist in drilling fluid
Compounding generates inhibition with stronger hydrate, and components of drilling liquid is small to environmental hazard, has efficient, environmental protection, original
Expect the advantages that cheap and easy to get.
In order to achieve the above object, the present invention adopts the following technical scheme that.
A kind of ocean gas hydrate stratum Compositional type drilling fluid, which is characterized in that the drilling fluid includes with the following group
Point:Sodium metasilicate mass ratio is 2.8%-3.2%, sodium chloride mass ratio is 9%-11%, methanol quality ratio be 4.5%-5.5%,
Quality of glycol ratio is 9%-11%, low viscosity carboxymethyl cellulose LV-CMC mass ratioes are 1.8%-2.2%, polyacrylic acid potassium
Mass ratio is 1.8%-2.2%, xanthans mass ratio is 0.4%-0.6%, Vinylcaprolactam homopolymer mass ratio is 0.8%-
1.2%, propylene glycol phenylate mass ratio is 0.8%-1.2%, tetra-n-butyl ammonium phosphate mass ratio is 0.8%-1.2%, remaining group
It is divided into preparation water.
Preferably, the drilling fluid includes following components:Sodium metasilicate mass ratio is 3%, sodium chloride mass ratio is 10%, first
Alcohol mass ratio is 5%, quality of glycol ratio is 10%, low viscosity carboxymethyl cellulose LV-CMC mass ratioes are 2%, polyacrylic acid
Potassium mass ratio is 2%, xanthans mass ratio is 0.5%, Vinylcaprolactam homopolymer mass ratio is 1%, propylene glycol phenylate quality
Than being 1% for 1%, tetra-n-butyl ammonium phosphate mass ratio, remaining components are to prepare water.
In above-mentioned drilling fluid, the sodium metasilicate increases as drilling fluid host agent, thickener, anti-sloughing agent in drilling process
Shale stability, and can mitigate stratum leakage degree, moderately prevent leakage, in the present invention inorganic salts sodium chloride and silicic acid
Sodium can generate synergistic effect, improve the rejection ability of drilling fluid, since sodium metasilicate barrier can form high efficiency permeable membrane, chlorine
The activity of water in drilling fluid can be reduced by changing sodium, and the fluid induced in shale gap enters from exudation in shale in drilling fluid, to
Achieve the purpose that shale goes aquation and improves shale stability.
In above-mentioned drilling fluid, the sodium chloride reduces the solidifying of drilling fluid as thermodynamic inhibitor, and as low-temperature resistance agent
Solid temperature degree.
In above-mentioned drilling fluid, the methanol is as thermodynamic inhibitor, kinetic inhibitor synergist;Methanol can be changed
The thermodynamic condition that hydrate generates, it is suppressed that the nucleation of hydrate.
In above-mentioned drilling fluid, the ethylene glycol is as low-temperature resistance agent, kinetic inhibitor synergist;Ethylene glycol is one kind two
First alcohol has stronger hydrogen bond Forming ability, after being mixed with water, can form firm hydrogen bond with water, can be greatly lowered
The freezing point of solution.
In above-mentioned drilling fluid, the low viscosity carboxymethyl cellulose LV-CMC is used as fluid loss additive.
In above-mentioned drilling fluid, the polyacrylic acid potassium is used as anti-sloughing agent.
In above-mentioned drilling fluid, the xanthans is used as creeping agent, the flow pattern of adjusting drilling well liquid.
In above-mentioned drilling fluid, the Vinylcaprolactam homopolymer is used as kinetic inhibitor, and propylene glycol phenylate,
As kinetic inhibitor synergist, compounding the inhibition of kinetic inhibitor more individually makes for tetra-n-butyl ammonium phosphate, methanol
It is significantly improved when with kinetic inhibitor;The Vinylcaprolactam homopolymer with N- caprolactams (VCL) be monomer,
Azodiisobutyronitrile is initiator, is synthesized by solution polymerization process, and synthetic method is known technology, not in this patent protection
Hold, wherein N- caprolactams (VCL) produce for BASF AG, purity 100%;Azodiisobutyronitrile
It is produced for Tianjin Zhi Yuan chemical reagent Co., Ltd, analysis is pure.
In above-mentioned drilling fluid, the preparation water is conventional source water water, such as river water, well water and filtered seawater etc.;It bores
Well liquid preparation method is conventional drilling liquid making method.
The drilling fluid cools down equipment in use, corresponding drilling fluid can be equipped in drilling platforms, for controlling drilling fluid
Low temperature;It can be equipped with corresponding solid control equipment in drilling platforms, the clay particle for that will be distributed in drilling fluid removes, and reaches drop
Low-soild effect.
The drilling fluid in use, make a trip, more bit change and well logging when, can as needed into drilling fluid be added weight
Spar improves drilling fluid density, for inhibiting decomposition of hydrate, prevents blowout, drilling fluid density is adjusted to 1.2-2.0g/
cm3, when subsequent well taken out barite by ground recycle unit, and drilling fluid is made to restore initial density.
Chlorination can be added in use, in case of saline bed, mud shale easily collapse stratum in the drilling fluid into drilling fluid system
Calcium solution.
The drilling fluid in use, can be needed according to practical storage alkalinity control agent is added adjust pH value 9-10 it
Between.
The present invention the advantage is that compared with the existing technology:
1, the present invention uses sodium metasilicate as drilling fluid host agent, and is clay-free drilling fluid, has good rheological characteristic, and
Can increase to the shale stability in drilling process, and more can fully carry and hang gang drill bits, can effectively reduce and
It prevents the repetition of drilling cuttings broken, and the degree of stratum leakage can be mitigated, moderately prevent leakage.
2, drilling fluid of the present invention can solve the problems, such as that hydrate generates in gas hydrates storage drilling process, can prevent
Bit freezing caused by forming hydrate in drilling process, the safety accidents such as preventer and catheter blockage.
3, drilling fluid of the present invention has good low-temperature stability, keeps low-temperature condition by controlling drilling fluid, can prevent
Gas hydrates store drilling process in foot of hole position hydrate a large amount of decomposition, can avoid cause aperture seriously expand,
The accidents such as blowout, well slough, casing deformation and surface subsidence.
4, drilling fluid of the present invention damages small caused by reservoir, is conducive to that gas water is found and protected in drilling process
Close produce layer.The drilling fluid has the characteristics that Solid Free, low-density, therefore, nearly balance can be achieved in drilling process even
Underbalance pressure drilling can effectively reduce intrusion of the solid phase to stratum, to advantageously reduce to gas hydrates reservoir
Damage.
5, drilling fluid of the present invention uses Compositional type hydrate inhibitor, is compounded by kinetic inhibitor and synergist,
Hydrate generates inhibition relatively exclusive use kinetic inhibitor and is obviously improved, and ocean gas hydrate is stored up
It hides, the decomposition of hydrate can be reduced, to reduce the probability for causing submarine landslide or foundation of sea floor unstability.
Specific implementation mode
Experimental method used in following embodiments is conventional method unless otherwise specified.
The sodium metasilicate used in following embodiments produces for Tianjin Zhi Yuan chemical reagent Co., Ltd, and analysis is pure;Chlorination
Sodium is the prosperous prosperous Chemical Co., Ltd.'s production in Tianjin, and analysis is pure;Methanol produces for the Guangdong rivers Weng chemical reagent Co., Ltd, point
It analyses pure;Ethylene glycol produces for Tianjin Zhi Yuan chemical reagent Co., Ltd, and analysis is pure;Low viscosity carboxymethyl cellulose LV-CMC is
The sincere hundred million Chemical Co., Ltd.s production of Renqiu City;Polyacrylic acid potassium produces for Hebei Yan Xing Chemical Co., Ltd.s;Xanthans is Renqiu
The sincere hundred million Chemical Co., Ltd.s production in city;Propylene glycol phenylate produces for Dow Chemical company, and analysis is pure;Tetra-n-butyl ammonium phosphate
It is produced for Henan Longhua chemical product Co., Ltd of Zhengzhou section, content 97%;Methane gas comes from the limited public affairs of Wuhan China star industrial technology
Department, purity 99.9%.
In the following embodiments, each noun dummy suffix notation, unit correspondence are as follows:Temperature, is abbreviated as T, and unit is Celsius
Degree;Apparent viscosity writes a Chinese character in simplified form AV, unit mPa.s;Plastic viscosity is abbreviated as PV, unit mPa.s;Yield value is abbreviated as YP, unit
Pa;Filter loss is abbreviated as FL, unit ml.
Embodiment one, each component content is in drilling fluid:Sodium metasilicate mass ratio is 2.8%, sodium chloride mass ratio is 9%,
Methanol quality ratio is 4.5%, quality of glycol ratio is 9%, low viscosity carboxymethyl cellulose LV-CMC mass ratioes are 1.8%, poly-
Potassium acrylate mass ratio is 1.8%, xanthans mass ratio is 0.4%, Vinylcaprolactam homopolymer mass ratio is 0.8%, the third two
Alcohol phenylate mass ratio is 0.8%, tetra-n-butyl ammonium phosphate mass ratio is 0.8%, and remaining components are to prepare water.
Embodiment two, each component content is in drilling fluid:Sodium metasilicate mass ratio is 3%, sodium chloride mass ratio is 10%, first
Alcohol mass ratio is 5%, quality of glycol ratio is 10%, low viscosity carboxymethyl cellulose LV-CMC mass ratioes are 2%, polyacrylic acid
Potassium mass ratio is 2%, xanthans mass ratio is 0.5%, Vinylcaprolactam homopolymer mass ratio is 1%, propylene glycol phenylate quality
Than being 1% for 1%, tetra-n-butyl ammonium phosphate mass ratio, remaining components are to prepare water.
Embodiment three, each component content is in drilling fluid:Sodium metasilicate mass ratio is 3.2%, sodium chloride mass ratio is 11%,
Methanol quality ratio is 5.5%, quality of glycol ratio is 11%, low viscosity carboxymethyl cellulose LV-CMC mass ratioes are 2.2%, poly-
Potassium acrylate mass ratio is 2.2%, xanthans mass ratio is 0.6%, Vinylcaprolactam homopolymer mass ratio is 1.2%, the third two
Alcohol phenylate mass ratio is 1.2%, tetra-n-butyl ammonium phosphate mass ratio is 1.2%, and remaining components are to prepare water.
One, two, three drilling fluid allocation method of above-described embodiment is conventional drilling liquid configuration method, passes through following experimental method
It is evaluated:
1 drilling fluid Shale Hydration inhibition is evaluated
When carrying out the Lab-evaluation of correlated performance to drilling fluid, inhibition evaluation experimental is one of important composition portion
Point, the present invention is tested using mud shale expansion Inhibition test, and specific experiment data are as shown in table 1.
1 aquation inhibition of table evaluates data
As can be seen from Table 1, under the same conditions, inhibition energy of one, two, three drilling fluid system of embodiment to shale expansion
Power is clearly.Wherein, initial 2 hour line percent expansion is only 3.5%, 3.4%, 3.3%, and at the end of testing, 16 is small
When line percent expansion be only 7.3%, 7.1%, 6.9%, and the clear water to compare mutually be 40.3%;In experimentation, clearly
Shale expansion percentage in water is in over time the trend to increase substantially, and shale is swollen in embodiment drilling fluid
The variation of swollen percentage is but relatively steady, and when experiment proceeds to 16h, the expansion rate variation of shale is smaller, expansion rate variation by
Gradually tend towards stability.It can be seen that the drilling fluid system can significantly reduce the hydration swelling amount of mud shale, it can be effectively prevented ground
Layer hole instability caused by due to aquation.
2 drilling fluid low temperature rheological behaviours are evaluated
Seabed formation temperature containing hydrate is generally 0 DEG C -4 DEG C, creeps into hydrate formation to decompose inhibition method, often passes through drop
The temperature of low drilling fluid inhibits the decomposition of hydrate, it requires that drilling fluid temperature is less than formation temperature, and with good
Cryogenic property.
In the experiment of drilling fluid low temperature rheological behaviour, cooling drilling fluid is to a certain constant first in high-low temperature test chamber
Temperature.When the temperature of drilling fluid, which is reduced to, tests required a certain steady temperature, continue at this temperature 1 hour
It is cooling.Period at the uniform velocity stirs drilling fluid with glass bar two minutes in every 15 minutes, and the temperature inside drilling fluid is made to keep uniformly dividing
Then cloth tests the rheological parameter of drilling fluid by six fast electronic rotation viscosimeters at this temperature.Wait for that rheological characteristic is tested
After finishing, the density of drilling fluid is tested with densimeter rapidly, tests the filter loss of drilling fluid immediately later.It finally measures and includes
The situation of change of drilling fluid rheology under the conditions of 10 DEG C, 5 DEG C, 0 DEG C, -5 DEG C, -10 DEG C.
Experiment test property of the drilling fluid in 5 different temperatures, experimental result such as following table.
The rheological characteristic of 2 embodiment of table, one drilling fluid at different temperatures
T(℃) | ρ(g/cm3) | Gel(Pa/Pa) | PV(mPa.s) | YP(Pa) | Fl(ml) |
10 | 1.11 | 1.5/2 | 15.7 | 6.5 | 6.7 |
5 | 1.13 | 1.5/2 | 17.8 | 6.9 | 6.6 |
0 | 1.14 | 2/2.5 | 19.9 | 7.4 | 6.5 |
-5 | 1.14 | 2/2.5 | 22.2 | 7.7 | 5.9 |
-10 | 1.14 | 2/2.5 | 22.7 | 7.9 | 5.7 |
The rheological characteristic of 3 embodiment of table, two drilling fluid at different temperatures
T(℃) | ρ(g/cm3) | Gel(Pa/Pa) | PV(mPa.s) | YP(Pa) | Fl(ml) |
10 | 1.13 | 1.5/2 | 17.0 | 6.7 | 6.6 |
5 | 1.14 | 1.5/2 | 18.8 | 7.0 | 6.4 |
0 | 1.16 | 2/2.5 | 20.6 | 7.2 | 5.9 |
-5 | 1.16 | 2/2.5 | 22.7 | 7.7 | 5.8 |
-10 | 1.16 | 2/2.5 | 23.8 | 8.2 | 5.6 |
The rheological characteristic of 4 embodiment of table, three drilling fluid at different temperatures
T(℃) | ρ(g/cm3) | Gel(Pa/Pa) | PV(mPa.s) | YP(Pa) | Fl(ml) |
10 | 1.15 | 1.5/2 | 17.9 | 6.9 | 6.5 |
5 | 1.16 | 1.5/2 | 19.7 | 7.2 | 6.3 |
0 | 1.17 | 2/2.5 | 20.8 | 7.6 | 5.9 |
-5 | 1.17 | 2/2.5 | 22.9 | 7.9 | 5.7 |
-10 | 1.17 | 2/2.5 | 25.0 | 8.4 | 5.4 |
From table 2-4 it is found that as temperature reduces, the plastic viscosity and shear force of drilling fluid increase, but change it is little, all can
In the range of receiving.In addition, drilling fluid ratio of dynamic shear force/yield value to plastic viscosity is higher, be conducive to cutting carring, clean wellbore, filter loss reduce with temperature and
It reduces.Rheological characteristic and stability are preferable under cryogenic for the drilling fluid configured.
3 methane hydrates, which generate, inhibits evaluation
In terms of the hydrate of drilling fluid generates rejection evaluation, the present invention is tested in autoclave by acquiring
The variation of temperature, pressure and other parameters in the process, and the directly observation of visualization window is combined to carry out;Experimental test procedures are:It is first
First the drilling fluid of prepared certain volume is put into reaction kettle, methane gas is passed through, sets high pressure low temperature experimental enviroment,
Air source is cut off, data acquisition software is opened, collected temperature, pressure data are protected in the temperature and pressure variation in observing response kettle
It deposits, during the experiment, in order to simulate drill string rotation, control mixing speed is 200r/min, is surveyed under conditions of there is disturbance
The hydrate inhibition effect of examination drilling fluid of the present invention.
During deepwater drilling, drilling fluid is about 2-4h from shaft bottom to drilling platforms cycle period, according to API standard with
And General Experimental Procedures, under the conditions of the certain water of simulation bathybic temperature and pressure, the drilling fluid containing hydrate inhibitor
It is generated without hydrate in 16h, that is, illustrates that the drilling fluid can meet requirement of the deepwater drilling to hydrate inhibition, experimental temperature
2 DEG C, -5 DEG C, -10 DEG C of selection, pressure select 5mPa, 10mPa, 15mPa, mixing speed 200r/min, experimental period selection
16h。
Comparative example 1
Deionized water is fitted into the reaction kettle of gas hydrates inhibition evaluation experimental device, simulation 500m depth is bored
Well environment, i.e. experimental pressure are 5mPa, and experimental temperature is 2 DEG C, mixing speed 200r/min, the generation of hydrate in reaction kettle
Time is 1.7h.
Comparative example 2
Sodium chloride is configured to the aqueous solution that mass percent is 10%, is packed into gas hydrates inhibition evaluation experimental
In the reaction kettle of device, 1500m depth drilling environments are simulated, i.e. experimental pressure is 15MPa, and experimental temperature is 2 DEG C, mixing speed
200r/min, the generated time of hydrate is 3.2h in reaction kettle.
5 hydrate of table, which generates, inhibits tables of data
Number | Initial pressure (MPa) | Final pressure (MPa) | Pressure drop (MPa) | Temperature (DEG C) |
Embodiment one | 5 | 4.82 | 0.18 | 2 |
Embodiment one | 10 | 9.73 | 0.27 | -5 |
Embodiment one | 15 | 14.64 | 0.36 | -10 |
Embodiment two | 5 | 4.83 | 0.17 | 2 |
Embodiment two | 10 | 9.74 | 0.26 | -5 |
Embodiment two | 15 | 14.65 | 0.35 | -10 |
Embodiment three | 5 | 4.84 | 0.16 | 2 |
Embodiment three | 10 | 9.75 | 0.25 | -5 |
Embodiment three | 15 | 14.66 | 0.34 | -10 |
The result shows that:In one, two, three drilling fluid system experimentation of embodiment, reacting kettle inner pressure and temperature are 16
That apparent variation does not occur in the reaction time of hour, pressure curve more steadily, is dissolved in interior gas always after uncapping
Body is released in seconds, does not observe the generation of hydrate, accordingly it is found that drilling fluid system of the present invention can be in dynamic environment very
Inhibit the generation of hydrate well.
4 contamination resistances are evaluated
Test drilling fluid contamination resistance:It is surveyed after a certain amount of bentonite (4%, 8%) maintenance 72h is added in drilling fluid
Its performance is tried, contamination resistance is evaluated, test temperature is 5 DEG C, as a result be see the table below.
6 embodiment of table, one drilling fluid system contamination resistance is evaluated
Formula | ρ(g/cm3) | Gel(Pa/Pa) | PV(mPa.s) | YP(Pa) | Fl(ml) |
Embodiment one | 1.13 | 1.5/2 | 17.8 | 6.9 | 6.6 |
One+4% bentonite of embodiment | 1.17 | 2/2.5 | 19.4 | 7.6 | 5.8 |
One+8% bentonite of embodiment | 1.2 | 2.5/3 | 20.7 | 8.8 | 5.2 |
7 embodiment of table, two drilling fluid system contamination resistance is evaluated
Formula | ρ(g/cm3) | Gel(Pa/Pa) | PV(mPa.s) | YP(Pa) | Fl(ml) |
Embodiment two | 1.14 | 1.5/2 | 18.8 | 7.0 | 6.4 |
Two+4% bentonite of embodiment | 1.18 | 2/2.5 | 20.4 | 7.7 | 5.6 |
Two+8% bentonite of embodiment | 1.21 | 2.5/3 | 21.9 | 8.9 | 4.9 |
8 embodiment of table, three drilling fluid system contamination resistance is evaluated
Formula | ρ(g/cm3) | Gel(Pa/Pa) | PV(mPa.s) | YP(Pa) | Fl(ml) |
Embodiment three | 1.16 | 1.5/2 | 19.7 | 7.2 | 6.3 |
Three+4% bentonite of embodiment | 1.2 | 2/2.5 | 20.8 | 7.8 | 5.5 |
Three+8% bentonite of embodiment | 1.22 | 2.5/3 | 22.5 | 9.1 | 4.8 |
After 4% and 8% bentonite is added in drilling fluid it can be seen from table 6-8, the viscosity and shear force of drilling fluid on
It rises, but amplitude of variation is little, shows that the drilling fluid contamination resistance is stronger.
5 rate of recovery are evaluated
The rate of recovery that drilling fluid is tested by rolling dispersion experiment, using certain block seabed landwaste as test object, 80
Heat rolling 16h at DEG C, the sieve for being 0.45mm with aperture recycle, and the experimental data are shown in the following table.
The different system rolling rate of recovery comparisons of table 9
System | Primary recovery (%) | Secondary returning yield (%) |
Embodiment one | 90.8 | 89.7 |
Embodiment two | 90.9 | 89.9 |
Embodiment three | 91.5 | 90.2 |
As can be seen from Table 9, the rate of recovery of drilling fluid system is higher, and the primary and secondary rate of recovery reaches 90% or so,
Landwaste primary recovery reacts drilling fluid chemistry inhibition power, and landwaste of the secondary returning yield reaction after mud soak exists
Dispersibility in clear water, dispersibility is smaller to illustrate that the suppressed effect of landwaste is stronger, and the borehole wall more they tends to stablize.
6 lubricities are tested
Using drilling fluid extreme boundary lubrication instrument, the extreme boundary lubrication coefficient of drilling fluid of the present invention is tested, the results showed that three realities
The extreme boundary lubrication coefficient for applying example is respectively 0.0915,0.0924,0.0933, within 0.1, shows that drilling fluid of the present invention has
Good lubricity.
Claims (2)
1. a kind of ocean gas hydrate stratum Compositional type drilling fluid, which is characterized in that the drilling fluid includes following components:
Sodium metasilicate mass ratio is 2.8%-3.2%, sodium chloride mass ratio is 9%-11%, methanol quality ratio is 4.5%-5.5%, second two
Alcohol mass ratio is 9%-11%, low viscosity carboxymethyl cellulose LV-CMC mass ratioes are 1.8%-2.2%, polyacrylic acid potassium quality
Than for 1.8%-2.2%, xanthans mass ratio be 0.4%-0.6%, Vinylcaprolactam homopolymer mass ratio is 0.8%-
1.2%, propylene glycol phenylate mass ratio is 0.8%-1.2%, tetra-n-butyl ammonium phosphate mass ratio is 0.8%-1.2%, remaining group
It is divided into preparation water.
2. a kind of ocean gas hydrate stratum Compositional type drilling fluid as described in claim 1, which is characterized in that the brill
Well liquid includes following components:Sodium metasilicate mass ratio is 3%, sodium chloride mass ratio is 10%, methanol quality ratio is 5%, ethylene glycol
Mass ratio is 10%, low viscosity carboxymethyl cellulose LV-CMC mass ratioes are 2%, polyacrylic acid potassium mass ratio is 2%, xanthans
Mass ratio is 0.5%, Vinylcaprolactam homopolymer mass ratio is 1%, propylene glycol phenylate mass ratio is 1%, tetra-n-butyl phosphoric acid
Ammonium mass ratio is 1%, and remaining components are to prepare water.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201810262424.3A CN108359427A (en) | 2018-03-28 | 2018-03-28 | A kind of ocean gas hydrate stratum Compositional type drilling fluid |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN201810262424.3A CN108359427A (en) | 2018-03-28 | 2018-03-28 | A kind of ocean gas hydrate stratum Compositional type drilling fluid |
Publications (1)
Publication Number | Publication Date |
---|---|
CN108359427A true CN108359427A (en) | 2018-08-03 |
Family
ID=63001796
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN201810262424.3A Withdrawn CN108359427A (en) | 2018-03-28 | 2018-03-28 | A kind of ocean gas hydrate stratum Compositional type drilling fluid |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN108359427A (en) |
-
2018
- 2018-03-28 CN CN201810262424.3A patent/CN108359427A/en not_active Withdrawn
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN108611069A (en) | A kind of argillaceous siltstoue natural gas hydrate stratum Compositional type drilling fluid | |
CN108611072A (en) | A kind of ocean gas hydrate storage Compositional type drilling fluid | |
CN108441187A (en) | A kind of Compositional type ocean gas hydrate storage drilling fluid | |
CN108359421A (en) | A kind of sea bed gas hydrate stratum Compositional type drilling fluid | |
CN108611073A (en) | A kind of siltstone gas hydrates storage Compositional type drilling fluid | |
CN108611066A (en) | A kind of argillaceous siltstoue gas hydrates storage Compositional type drilling fluid | |
CN108611077A (en) | A kind of permafrost region gas hydrates storage Compositional type drilling fluid | |
CN108728061A (en) | A kind of frozen soil layer gas hydrates storage Compositional type drilling fluid | |
CN108611063A (en) | A kind of Compositional type frozen soil layer gas hydrates storage drilling fluid | |
CN108359427A (en) | A kind of ocean gas hydrate stratum Compositional type drilling fluid | |
CN108441181A (en) | A kind of drilling fluid suitable for ocean gas hydrate storage | |
CN108611068A (en) | A kind of marine gas hydrate formation Compositional type drilling fluid | |
CN108611067A (en) | A kind of drilling fluid for ocean gas hydrate storage | |
CN108441193A (en) | A kind of ocean hydrate storage polyvinyl alcohol composite type drilling fluid | |
CN108441186A (en) | A kind of Compositional type marine gas hydrate storage drilling fluid | |
CN108611074A (en) | A kind of drilling fluid for marine gas hydrate storage | |
CN108251083A (en) | A kind of Compositional type sea bottom hydrate stores polyvinyl alcohol drilling fluid | |
CN108441191A (en) | A kind of sea bottom hydrate storage polyvinyl alcohol composite type drilling fluid | |
CN108359422A (en) | A kind of drilling fluid suitable for marine gas hydrate storage | |
CN108441188A (en) | A kind of Compositional type ocean hydrate stores polyvinyl alcohol drilling fluid | |
CN108251081A (en) | A kind of marine gas hydrate stores Compositional type drilling fluid | |
CN108441189A (en) | A kind of sea bottom hydrate storage polyvinyl alcohol type drilling fluid | |
CN108441182A (en) | A kind of sea bed gas hydrate storage Compositional type drilling fluid | |
CN108359428A (en) | A kind of drilling fluid suitable for sea bed gas hydrate storage | |
CN108359423A (en) | A kind of drilling fluid for argillaceous siltstoue gas hydrates storage |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
WW01 | Invention patent application withdrawn after publication |
Application publication date: 20180803 |
|
WW01 | Invention patent application withdrawn after publication |