JP6531604B2 - Composition comprising wood fiber - Google Patents

Description

  The present invention relates to a composition comprising wood fiber, a water soluble polymer and a solvent. In particular, the invention relates to wood fiber containing compositions having high viscosity and good particle dispersibility.

  In recent years, there has been an increase in the tendency to actively use renewable resources. For example, fibrous cellulose is widely known as a reproducible resource, and among them, fibrous cellulose derived from wood has been widely used mainly as a raw material of paper products.

  The fine fibrous pulverized material of cellulose fine powder or particles has high affinity to water because of its large surface area, strong ability to hold water, high viscosity even at low concentration, and excellent suspension stability Because it can form a suspension, it is useful as an excellent humectant, dispersant, thickener.

The application of fibrous cellulose or pulp is widely considered, and its use in various compositions is being considered.
Patent Document 1 shows a swollen highly water-absorptive polymer stabilizer composition for soil excavation containing water and highly water-absorptive polymer particles, wherein the specific gravity of the swollen highly water-absorptive polymer stabilizer composition for ground excavating is 1.20 or less A swollen superabsorbent polymer stabilizer composition for ground excavations is described which is in the range of Patent document 1 includes that an auxiliary material for improving the pore wall stability may be contained, and the auxiliary material is selected from bentonite, sawdust, pulp, rock wool, anti-soiling material such as fiber, or water-soluble polymer. It is described that it is at least one of

  In addition, Patent Document 2 describes a hydraulic composition containing ground granulated blast furnace slag, an ultrafine powdery substance, a water-soluble polymer, a curing stimulant, an aggregate, a natural fiber and water. The hydraulic composition described in Patent Document 2 contains 3 parts by weight to 10 parts by weight of natural fiber with respect to the total weight 100 parts by weight of granulated blast furnace slag and the ultrafine powdery substance, and contains water in the composition. The proportion is 18 to 23% by weight.

JP, 2013-57061, A JP 10-120456 A

When using fibrous cellulose as a thickener, it is desired that the fibrous cellulose-containing composition has high viscosity and at the same time exhibits good particle dispersibility.
As described in the background art, a fine fibrous grind of cellulose fine powder or particles is useful as a thickener, but depending on the type of fibrous cellulose, the fibrous cellulose-containing composition does not exhibit sufficient viscosity There is a case. Furthermore, even if the fibrous cellulose-containing composition exhibits high viscosity, the particle dispersibility may be poor.

  Patent Document 1 describes a swollen highly water-absorptive polymer stabilizer composition for excavating ground, which contains an auxiliary material such as a fiber and a water-soluble polymer, in addition to water and highly water-absorptive polymer particles. There is no discussion of the influence of the above on the properties of the composition (in particular, the viscosity and the particle dispersibility). In addition, although the hydraulic composition described in Patent Document 2 can give a cured product having improved nonflammability and is described as being useful as a building material, the fiber property is the property of the composition. The influence on (particularly, viscosity and particle dispersibility) has not been studied.

  The problem to be solved by the present invention is to provide a wood fiber-containing composition which has high viscosity and at the same time exhibits good particle dispersibility. Furthermore, another problem to be solved by the present invention is to provide a fluid for treating an underground layer, which contains the above-mentioned wood fiber-containing composition. Furthermore, another problem to be solved by the present invention is to provide a method of treating an underground layer using the above-mentioned wood fiber-containing composition, and a method of producing petroleum resources. Furthermore, another problem to be solved by the present invention is to provide a method for producing the above-mentioned wood fiber-containing composition.

  As a result of intensive studies to solve the above problems, the present inventors have found that, by blending wood fiber and a water-soluble polymer in a solvent, the freeness and lignin content in the solid content satisfy the predetermined conditions. It has been found that a composition can be provided which exhibits a viscosity and good particle dispersibility. The present invention has been completed based on these findings.

That is, according to the present invention, the following inventions are provided.
(1) wood fiber having (a) freeness of 50 to 300 and lignin content of 5 to 25% by mass in solid content, (b) water-soluble polymer, and (c) solvent Composition containing.
(2) The composition according to (1), wherein the wood fiber comprises at least fibrous cellulose.
(3) The composition as described in (1) or (2) whose solid content concentration of wood fiber is 0.2 mass% or more and 1 mass% or less.
(4) The composition according to any one of (1) to (3), wherein the water-soluble polymer is a nonionic polymer.

(5) The composition according to any one of (1) to (4), wherein the water-soluble polymer is a natural polysaccharide.
(6) The composition according to any one of (1) to (5), wherein the solid content concentration of the water-soluble polymer is 0.1% by mass or more and 1% by mass or less.
(7) The composition according to any one of (1) to (6), wherein the solvent is water.
(8) The composition according to any one of (1) to (7), which is used as a thickener (9) A composition for treating an underground layer according to any one of (1) to (8) Composition.

(10) Fracturing fluid, mud water, cementing fluid, well control fluid, well kill fluid, acid fracturing fluid, acid diverting fluid, stimulating fluid (Stimulation fluid), sand control fluid, completion fluid, wellbore consolidation fluid, remediation treatment fluid, spacer fluid, drilling fluid The composition according to (9) for use in addition to (drilling fluid), fracturing packing fluid (frac-packing fluid), water-conforming fluid (grave packing fluid), or gravel packing fluid object.

(11) The composition as described in (9) or (10), as well as a weighting agent, a viscosity modifier, a dispersant, a coagulant, an anti-smud agent, a dehydration regulator, a pH regulator, a friction modifier, a hydration expansion At least one selected from the group consisting of control agents, emulsifiers, surfactants, biocides, antifoams, scale inhibitors, corrosion inhibitors, temperature stabilizers, resin coatings, crack supports, salts, and proppants Underground processing fluids, including:
(12) The fluid for treatment of an underground layer according to (11), which is a fracturing fluid, muddy water or cementing fluid.
(13) A method of treating an underground layer, comprising treating the underground layer with the composition according to (9) or (10) or the fluid according to (11) or (12).

(14) A method of producing petroleum resources, comprising treating an underground formation with the composition according to (9) or (10), or the fluid according to (11) or (12).
(15) the step of concentrating or drying the dispersion of wood fibers, and re-dispersing the obtained concentrate or dried product and the water-soluble polymer in a solvent to obtain a re-dispersion, from (1) to (10) The manufacturing method of the composition in any one of to.
(16) from the step (1), comprising the steps of: concentrating or drying the dispersion containing wood fiber and the water-soluble polymer, and re-dispersing the obtained concentrate or dried product in a solvent to obtain a re-dispersion 10) The manufacturing method of the composition in any one of 10).
(17) The production method according to (15) or (16), wherein the concentration is carried out by any of a concentration agent, a dryer, or filter dehydration.

  According to the present invention, a composition having high viscosity and excellent particle dispersibility can be provided. The composition of the present invention can be used, for example, as a thickener, and can be used in a wide range of fields including industrial products such as pharmaceuticals, cosmetics, foods, and construction fields. In particular, the composition of the present invention can be used in fluids involved in oil, gas production where the need for high viscosity thickeners is very high.

  Values for the mass of fibers such as cellulose are based on bone dry mass (solids) unless otherwise stated. Also, the numerical range "X to Y" includes the values at both ends, unless otherwise specified.

[Composition of the present invention]
The composition of the present invention comprises (a) wood fibers having a freeness of 50 to 300 and a lignin content of 5 to 25% by mass in the solid content, (b) a water-soluble polymer, and (c And a solvent. In a composition formulated in a solvent together with a water-soluble polymer, by using a wood fiber having a freeness of 50 or more and 300 or less and a lignin content in the solid content of 5% by mass or more and 25% by mass or less It has become possible to achieve both high viscosity and good particle dispersibility.

<Wood fiber>
Examples of wood fibers include paper pulp, cotton-based pulp such as cotton linter and cotton lint, non-wood-based pulp such as hemp, straw, bagasse, and cellulose isolated from sea squishy or seaweed, but is not particularly limited. . The wood fiber preferably contains at least fibrous cellulose, but is not particularly limited. The wood fibers may include fibrous cellulose and hemicellulose. As the wood fibers, machined ones such as defibration treatment described later can be used.

Examples of the pulp include chemical pulp, semi-chemical pulp, mechanical pulp, non-wood pulp, and deinked pulp made from waste paper, among which mechanical pulp is preferred. As mechanical pulp, there are ground pulp (GP), bleached ground pulp (BGP), unbleached ground pulp (UGP), thermomechanical pulp (TMP, BCTMP) and the like. The raw materials of wood fiber may be used singly or in combination of two or more.
The solid content concentration of wood fiber in the composition of the present invention is preferably 0.2% by mass or more and 1% by mass or less, more preferably 0.3% by mass or more and 0.9% by mass or less, still more preferably Although it is 0.4 mass% or more and 0.8 mass% or less, it is not limited in particular.

<Disintegration processing>
As the wood fiber, one that has been subjected to disentanglement treatment may be used, or one that is not subjected to disentanglement treatment may be used. In the fibrillation treatment, usually, the fibrillation treatment device is used to fibrillate the wood fibers to obtain a fine fiber-containing slurry, but the treatment device and the treatment method are not particularly limited.
As the defibration processing apparatus, a high-speed fibrillation machine, a grinder (millstone type crusher), a high pressure homogenizer, an ultrahigh pressure homogenizer, a high pressure collision type crusher, a ball mill, a bead mill, etc. can be used. Alternatively, use an apparatus for wet grinding such as a disc refiner, a conical refiner, a twin screw kneader, a vibration mill, a homomixer under high speed rotation, an ultrasonic disperser, or a beater as a defibration treatment apparatus. You can also. The defibration processing apparatus is not limited to the above. Preferred defibration treatment methods include, but are not particularly limited to, a high-speed fibrillation machine, a high-pressure homogenizer, and an ultra-high pressure homogenizer, which are less affected by the grinding media and less likely to be contaminated.

  At the time of the defibration treatment, it is preferable to dilute the fiber raw material with water and an organic solvent singly or in combination to form a slurry, but it is not particularly limited. As the dispersion medium, polar organic solvents can be used in addition to water. Preferred polar organic solvents include, but are not particularly limited to, alcohols, ketones, ethers, dimethylsulfoxide (DMSO), dimethylformamide (DMF), and dimethylacetamide (DMAc). As alcohols, methanol, ethanol, n-propanol, isopropanol, n-butanol, or t-butyl alcohol etc. are mentioned. Examples of ketones include acetone or methyl ethyl ketone (MEK). Examples of ethers include diethyl ether or tetrahydrofuran (THF). The dispersion medium may be one type, or two or more types. The dispersion medium may also contain solid components other than the fiber material, such as urea having hydrogen bonding property.

  In the present invention, the composition containing wood fiber, water-soluble polymer and solvent may be concentrated and dried before being subjected to the defibration treatment. In this case, the method of concentration and drying is not particularly limited, and examples thereof include a method of adding a thickener to a slurry containing wood fibers, a method of using a generally used dehydrator, a press, and a dryer. Also, known methods can be used, such as the methods described in WO2014 / 024876, WO2012 / 107642, and WO2013 / 121086. Alternatively, concentrated wood fibers may be sheeted. The sheet can also be crushed and subjected to disintegration processing.

As an apparatus used for a grinding | pulverization at the time of grinding | pulverizing a wood fiber, although the following can be used, it does not specifically limit.
High-speed fibrillation machine, grinder (miller type crusher), high pressure homogenizer, ultra high pressure homogenizer, high pressure collision type crusher;
Ball mill, bead mill, disc type refiner, conical refiner, twin screw kneader, vibration mill, homomixer under high speed rotation, ultrasonic dispersion machine, beater:

<Characteristics of wood fiber>
The freeness of the wood fiber used in the present invention is 50 or more and 300 or less, and the lignin content in the solid content is 5% by mass or more and 25% by mass or less. By setting the freeness and the lignin content in the solid content in the above range, it is possible to provide a wood fiber-containing composition having high viscosity and at the same time exhibiting good particle dispersibility.

  The freeness of wood fiber is more preferably 70 or more and 280 or less, still more preferably 100 or more and 250 or less, still more preferably 120 or more and 230 or less, and particularly preferably 130 or more and 220 or less. Freeness can be measured in accordance with JIS P 8121.

For wood fibers, the lower limit of the lignin content in the solid content may be 5% by mass or more, preferably 7% by mass or more, more preferably 10% by mass or more, and still more preferably 15% by mass or more And particularly preferably 17% by mass or more. The upper limit of the lignin content in the solid content may be 25% by mass or less, preferably 23% by mass or less, and more preferably 22% by mass or less.
Measurement of lignin content in solid content can be calculated from L (%) = Kappa number × 0.13 according to TAPPI / ANSI T 236. The Kappa number can be measured in accordance with JIS P 8211.

<Fiber width and fiber length of wood fiber>
When the wood fiber contains fibrous cellulose, the fibrous cellulose may be coarse fibrous cellulose, fine fibrous cellulose, or a mixture of coarse fibrous cellulose and fine fibrous cellulose.

  The average fiber width of the coarse fibrous cellulose (sometimes simply referred to as coarse fibers) is, for example, 1 μm or more, preferably 5 μm or more, and more preferably 10 μm or more, as observed by an electron microscope.

  The average fiber width of the fine fibrous cellulose (sometimes simply referred to as fine fibers) is preferably 2 to 1000 nm, more preferably 2 to 100 nm, and more preferably 2 to 50 nm, as observed by an electron microscope. The thickness is more preferably 2 nm to 10 nm, but is not particularly limited. When the average fiber width of the fine fibrous cellulose is less than 2 nm, it is dissolved in water as a cellulose molecule, and thus the physical properties (strength, rigidity, and dimensional stability) as the fine fibrous cellulose are not expressed. Here, the fact that the fine fibrous cellulose has an I-type crystal structure can be identified in a diffraction profile obtained from a wide-angle X-ray diffraction photograph using CuKα (λ = 1.5418 Å) monochromatized with graphite. Specifically, it can be identified from having typical peaks at two positions near 2θ = 14 ° to 17 ° and 2θ = 22 ° to 23 °.

  The measurement of the fiber width by electron microscopic observation of fibrous cellulose is performed as follows. An aqueous suspension of fibrous cellulose having a concentration of 0.05 to 0.1% by mass is prepared, and the suspension is cast on a hydrophilized carbon film-coated grid to prepare a sample for TEM observation. If wide fibers are included, an SEM image of the surface cast on glass may be observed. Observation with an electron microscope image is performed at a magnification of 1000 times, 5000 times, 10000 times or 50000 times depending on the width of the fiber to be constructed. However, the sample, observation conditions and magnification are adjusted to satisfy the following conditions.

(1) One straight line X is drawn at an arbitrary position in the observation image, and 20 or more fibers cross the straight line X.
(2) Draw a straight line Y intersecting perpendicularly with the straight line in the same image, and 20 or more fibers cross the straight line Y.

  With respect to the observation image satisfying the above conditions, the width of the fiber intersecting with the straight line X and the straight line Y is visually read. Thus, three or more sets of images of at least non-overlapping surface portions are observed, and for each image, the width of the fiber intersecting the straight line X and the straight line Y is read. Thus, a fiber width of at least 20 x 2 x 3 = 120 is read. The average fiber width of the fibrous cellulose (simply called "fiber width") is the average value of the fiber widths read in this way.

  The fiber length of fibrous cellulose is not particularly limited, but is preferably 0.1 to 1000 μm, more preferably 0.1 to 800 μm, and particularly preferably 0.1 to 600 μm. When the fiber length is less than 0.1 μm, the crystalline region of fibrous cellulose is also broken, and the original physical properties can not be exhibited. If it exceeds 1000 μm, the slurry viscosity of the fiber becomes very high and it becomes difficult to handle. The fiber length can be determined from image analysis by TEM, SEM, AFM.

<Water-soluble polymer>
Examples of the water-soluble polymer used in the present invention include synthetic water-soluble polymers, natural polysaccharides, cellulose derivatives, starches, glycerins, hyaluronic acids and the like, but are not particularly limited. Examples of the synthetic water-soluble polymer include carboxyvinyl polymer, polyvinyl alcohol, alkyl methacrylate / acrylic acid copolymer, polyvinyl pyrrolidone, sodium polyacrylate, polyethylene glycol, polypropylene glycol, polyacrylamide and the like. Examples of natural polysaccharides include xanthan gum, guar gum, tamarind gum, carrageenan, locust bean gum, quince seed, alginic acid, pullulan, carrageenan, pectin and the like. As a cellulose derivative, carboxymethylcellulose, methylcellulose, hydroxyethylcellulose etc. can be mentioned, for example. Examples of starches include cationized starch, raw starch, oxidized starch, etherified starch, esterified starch, amylose and the like. As glycerins, polyglycerin etc. can be mentioned, for example. Examples of hyaluronic acids include hyaluronic acid, metal salts of hyaluronic acid, and the like.
Among the above, natural polysaccharides are particularly preferable as the water-soluble polymer, but it is not particularly limited.
Although the number average molecular weight of the water-soluble polymer is not particularly limited, it is generally 500 or more and 1,000,000 or less, and for example, 1,000 or more and 500000 or less.

  The water-soluble polymer may be any of a nonionic polymer, an anionic polymer, a cationic polymer, or an amphoteric polymer, and is not particularly limited, but preferably a nonionic polymer can be used.

  The solid content concentration of the water-soluble polymer in the composition of the present invention is preferably 0.1% by mass or more and 1% by mass or less, more preferably 0.1% by mass or more and 0.8% by mass or less The content is preferably 0.2% by mass or more and 0.5% by mass or less, but is not particularly limited.

<Solvent>
As a solvent used in the present invention, water, an organic solvent, or a mixture of water and an organic solvent can be used. As the solvent, water or a mixture of water and an organic solvent is preferable, and water is particularly preferable.

  Examples of the organic solvent include alcohols, ketones, ethers, dimethyl sulfoxide (DMSO), dimethylformamide (DMF), and dimethyl acetamide (DMAc), but are not particularly limited. As alcohols, methanol, ethanol, n-propanol, isopropanol, n-butanol, or t-butyl alcohol etc. are mentioned. Examples of ketones include acetone or methyl ethyl ketone (MEK). Examples of ethers include diethyl ether or tetrahydrofuran (THF).

  The content of the solvent in the composition of the present invention is preferably 50% by mass to 99.8% by mass, and more preferably 70% by mass to 99.8% by mass, but is not particularly limited.

<Characteristics of composition>
The composition of the present invention is a wood fiber-containing composition which has high viscosity and at the same time exhibits good particle dispersibility.
The viscosity of the composition can be measured by rotating for 3 minutes at a rotational speed of 3 rpm at 25 ° C. using a B-type viscometer (analog viscometer T-LVT, manufactured by BLOOK FIELD).
The viscosity of the composition of the present invention is preferably 70 mPa · s or more, more preferably 80 mPa · s or more, and still more preferably 100 mPa · s or more, but is not particularly limited. The upper limit of the viscosity is not particularly limited, but generally it is 20000 mPa · S or less, preferably 10000 mPa · S or less, more preferably 8000 mPa · S or less, particularly preferably 5000 mPa · s or less .

  The method for evaluating the particle dispersibility of the composition is not particularly limited, but the particles may be added to the composition of the present invention and stirred, and then the dispersibility of the particles may be evaluated. One example of the evaluation of the particle dispersibility is the evaluation method described in the examples described later.

<Method of producing composition>
The method for producing the composition of the present invention is not particularly limited, and wood fibers, a water-soluble polymer, and a solvent may be blended respectively. For example, the composition of the present invention may be produced as a dispersion by adding wood fiber and a water-soluble polymer to a solvent, respectively, and stirring using a disperser. Alternatively, the composition of the present invention is produced by a process of concentrating or drying a wood fiber dispersion, and re-dispersing the obtained concentrate or dry product and a water-soluble polymer in a solvent to obtain a re-dispersion liquid. You can also Also, the composition of the present invention is produced by the process of concentrating or drying a dispersion containing wood fibers and a water-soluble polymer, and re-dispersing the obtained concentrate or dried product in a solvent to obtain a re-dispersion. You can also
The concentration of wood fibers can be carried out either by means of a thickener, drier or filter dewatering.

<Use of the composition of the present invention>
The composition of the present invention can be used to modify various properties of the fluid by being added to the fluid, and can be used for various purposes taking advantage of such properties.
As a use of the composition of this invention, if it is a general use of wood fibers, such as fibrous cellulose, it can be used without a restriction | limiting especially. Specifically, thickener compositions, ie, applications such as thickeners and dispersants (compositions for treating underground layers, cosmetics, foods, beverages, etc.), friction modifiers, cold insulators, pharmaceuticals, bath agents, paints, Although the use of chemicals (agrochemicals etc.) etc. is mentioned, it is not particularly limited. Among the above, particularly preferably, the composition of the present invention can be used as a thickener or a composition for treating an underground layer.

The following applications can be mentioned, for example, in connection with underground treatment.
The composition of the present invention can be used as a thickener in the treatment of underground formations including seawater in the treatment of underground formations such as the seabed.
The composition of the present invention can be used as an anti-soiling agent and a dehydrating agent in the underground formation treatment fluid if it has water barrier properties.
When the composition of the present invention has thixotropic properties, it can exhibit excellent ability to form a well wall when used in mud. In addition, when used as a cementing fluid, it is possible to facilitate the press-in of cement. Thus, the composition of the present invention can be used as a tunnel wall former or cementing modifier.

  The composition of the present invention may also exhibit an emulsifying function by trapping oil droplets between the fine fiber network in the underground formation processing fluid, and can be expected to be used as an emulsifier. Specifically, it can be used for the use of an emulsion-based fluid for treatment of an underground layer, and the stabilization of an emulsion substance blended in the fluid for underground treatment. The compositions of the invention can be used at high temperatures, for example up to 300 ° C. The decomposition temperature of the fine fibrous cellulose is 300 ° C., and because of the high crystallinity, there is no melting point or glass transition point, and therefore there is no hetitation like a general resin. Therefore, it can also be used in high water depth wells.

  The composition of the present invention can be used by dispersing it in a suitable dispersion medium. The dispersion medium is not particularly limited as long as it can disperse fine fibrous cellulose, and water, an organic solvent, an oil (eg, light oil, mineral oil, synthetic oil, edible oil, non-food oil), etc. may be used. Can.

  Wood fibers contained in the composition of the present invention can be disassembled using a breaker. Disassembling can prevent viscosity control and retention in the underground layer. As the breaker, various components capable of decomposing wood fibers can be used. Examples thereof include, but are not limited to, oxidizing agents such as ammonium persulfate and sodium persulfate, acids such as hydrochloric acid and sulfuric acid, and enzymes such as cellulase.

  The wood fibers contained in the composition of the present invention can be crosslinked in order to improve the viscosity effect and the like. As the crosslinking agent, various components capable of crosslinking wood fibers can be used. Examples include, but are not limited to, borate, potassium hydroxide, nitrate, zirconium, titanium and the like.

[fluid]
The composition of the present invention can be used for thickening, anti-smudging, dehydration control, emulsification, pit formation, cementing control, as described above, and is resistant to salts, so it can be used to treat underground layers, For example, it can be added to various fluids used in well drilling. Such fluids include fracturing fluid, mud water, cementing fluid, well control fluid, well kill fluid, acid fracturing fluid, acid diverting fluid ), Stimulation fluid, sand control fluid, completion fluid, wellbore consolidation fluid, remediation treatment fluid, spacer fluid These include drilling fluid, frac-packing fluid, water-conforming fluid, gravel-packing fluid, and the like.

  When the composition of the present invention is used by being contained in a fluid, the content is not particularly limited as long as the intended effect is exhibited. Typically, the fluid may contain wood fibers at a solids concentration (as a total of wood fibers) at 0.005 to 10% by weight, preferably 0.01 to 5% by weight. More preferably, the solid content concentration of the wood fiber in the fluid is 0.05 to 2% by mass from the viewpoint that the waterproofness can be sufficiently exhibited even at high temperature.

<Other components in fluid>
The fluid provided by the present invention may contain, in addition to the composition of the present invention, various components added to the fluid for conventional underground treatment. Examples of components to be added include weighting agents, viscosity modifiers, dispersants, flocculants, anti-smud agents, dehydration regulators, pH regulators, friction modifiers, hydration / expansion regulators, emulsifiers, surfactants, Biocides, antifoams, scale inhibitors, corrosion inhibitors, temperature stabilizers, resin coatings, crack supports, salts and proppants can be mentioned, but are not limited thereto. Moreover, not only 1 type but 2 or more types of components may be added.

  The load material is used to increase the specific gravity of the fluid and to prevent the stability of the bare well wall and the emission of gas, water and the like. As a weighting material, minerals such as barite and hematite can be used, but are not limited thereto.

  Viscosity modifiers, also called gelling agents, thickeners, and thickeners, are used to optimize the viscosity of the fluid. As components for this purpose, in addition to minerals such as bentonite, atavalgite, sepiolite, synthetic squameite and the like, natural and synthetic polymers which are water soluble are used.

  One of the preferable examples of the water-soluble polymer is one derived from a natural polysaccharide. Specific examples of viscosity modifiers include natural products or natural products derived from guar gum and guar gum derivatives, methylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropylmethylcellulose, hydroxyethylmethylcellulose, glyoxal-added hydroxypropylmethylcellulose, carboxymethylcellulose, and carboxyl Water-soluble cellulose derivatives such as ethyl cellulose, gum arabic, alginic acid and esters thereof, alginate, eremi resin, gati gum, carrageenan, karaya gum, carob bean gum, polysaccharide thickener, tamarind gum, tragant gum, starch glycolate, starch salt, Although there are farcereran, glucose, glucose polysaccharides, sucrose, xanthan gum and the like, But it is not limited to these. The synthetic polymer includes, but is not limited to, hydrolyzed polyacrylamide (PHPA polymer), polyvinyl alcohol, polyacrylate polymer and the like.

  Anti-smudging agents are used to prevent the outflow of subsurface treatment fluids. As an anti-soiling agent, sawdust, straw, cellophane, cement, pulp fiber, polylactic acid, polyglycolic acid, polyarylate and the like can be used, but it is not limited thereto.

  Dehydration modifiers are used to reduce dewatering and to enhance the well-wall protection. As a dehydration regulator, a sulfonated asphalt derivative, a starch derivative, a polyarylate, a polyanionic cellulose-based polymer and the like are used, but it is not limited thereto.

  Emulsifiers are used to disperse in one liquid the other liquid which is usually difficult to mix. As an emulsifier, glycerin ester, saponin, sucrose fatty acid ester, lecithin, polyethylene glycol, polyoxyethylene cetyl ether, polyoxyethylene oleyl ether, polyoxyethylene stearyl ether, polyoxyethylene lauryl ether, polyoxyethylene octyl dodecyl ether, Polyoxyethylene decyl tetradecyl ether, polyoxyethylene behenyl ether, ethyl caprate, cetyl palmitate, stearyl stearate, cetyl octanoate, hexyl decyl isostearate, octyl isononanoate, dodecyl isononanoate, glycerin stearate, glycerin palmitate , Tri (caprylic acid capric acid) glycerin, sorbitan monostearate, sorbitan oleate, Propylene glycol thearylate, propylene glycol oleate, propylene glycol laurate, glycol stearate, glycol dioleate, polyethylene glycol monostearate, polyoxy ethylene glycol isostearate, polyoxyethylene hydrogenated castor oil laurate, polyoxyethylene hydrogenated castor oil Examples include, but are not limited to, oil, polyoxyethylene sorbitan fatty acid ester, dimethylconcopolyol.

  The proppant is a solid of about 0.5 mm, and is pressed into the fracture at the time of fracturing or the like, and used as a support so as not to close the fracture. Examples of proppants include, but are not limited to, sand, glass beads, ceramic particles, resin-coated sand, and the like.

(muddy water)
An example of a fluid containing the composition of the present invention is mud water used in well drilling. The content of fibrous cellulose in the muddy water is not particularly limited as long as the intended effect is exhibited. The muddy water contains fibrous cellulose in solid concentration (as the total amount of fibrous cellulose), for example, 0.004 to 40 mass%, preferably 0.04 to 4 mass%, and 0.08 to 2 mass It is more preferable to contain%.

Mud that is used during well drilling is generally used to remove debris from the well bottom and transport it to the ground. Mud water also controls the pressure in the well to prevent unintended fluid inflow and ejection to the ground, protects the well wall and prevents the collapse of the underground layer, and further drill string and It also has the role of reducing friction with the walls and cooling downhole equipment. It also plays a role in providing underground information by transporting waste and gas. The muddy water includes bentonite muddy water, lignosulfonate muddy water, KCl polymer muddy water, oil-based muddy water, etc. According to this embodiment, various kinds of muddy water are provided.

  In general, bentonite mud is cheap and easy to handle, but it is weak to salt and cement and tends to gel. Conventionally, carboxymethyl cellulose etc. may be added to supplement these determinations, but the present invention may provide bentonite mud with higher performance.

  According to the present invention, there is provided a dispersed mud comprising the composition of the present invention. Such mud fluid may contain conventional lignosulfonate (sometimes referred to as lignin sulfonic acid), lignite (humic acid derivative), pH adjuster (for example, sodium hydroxide), and a weighting agent as a dispersant. Dispersed mud, protection function of mudstone, ease of control of viscosity and specific gravity, temperature (usual use temperature of lignosulfonate mud is said to be about 175 ° C, working temperature of lignite mud is said to be about 190 ° C), salt, It can be expected that the resistance by cement etc. is further enhanced as compared with the conventional lignosulfonate mud water.

  The muddy water of the present invention can also be configured as KCl muddy water. It is known that K ions are very excellent in the action of suppressing swelling and dispersion of clays. On the other hand, it has been conventionally used in combination with xanthan gum or partially hydrolyzed polyacrylamide (PHPA) polymer, which can exhibit thickening and protective colloid even in a liquid containing a large amount of K ions because the cohesion is too strong. The The composition of the present invention can be used together with or in place of xanthan gum or PHPA. The KCl mud provided by the present invention is expected to have a higher ability to protect mudstone, ease of control of viscosity and specific gravity, and resistance by salt, cement, etc., as compared to conventional KCl-polymer mud. it can.

  The muddy water of the present invention can also be configured as an oil-based muddy water. The oil-based mud includes an invert emulsion oil mud which is an emulsion of water-in-oil type prepared using an oil mud having an oil content of 95% by mass or more, and 15 to 35% by mass of water and an emulsifier. Oil-based mud, in general, suppresses hydration / swelling of mudstone, suppresses high temperature stability, lubricity, prevents productivity damage due to water infiltration into oil, and less causes metal corrosion compared to aqueous mud. , There are advantages such as less deterioration due to corruption. According to this embodiment, it can be expected that a further improved oil-based mud can be provided while taking advantage of these characteristics.

(Fracturing fluid)
One example of a fluid comprising the composition of the present invention is a fracturing fluid used in pressure crushing. The content of fibrous cellulose in the fracturing fluid is not particularly limited as long as the intended effect is exhibited. The fracturing fluid contains fibrous cellulose in solid concentration (as the total amount of fibrous cellulose), for example, 0.002 to 20% by mass, preferably 0.02 to 2% by mass, 0.04 It is more preferable to contain 1 mass%.

  The fragmentation fluid generally contains about 90 to 95% by mass of water or an organic solvent as a solvent or dispersion medium, and about 5 to 9% by mass of proppant (support). Furthermore, depending on the case, it contains 0.5 to 1% by mass of various additives such as gelling agent, scale inhibitor, acid for dissolving rock and the like, friction reducing agent and the like. These components and additives can also be contained in the same range as the fracturing fluid of the present invention.

  Fibrous cellulose, in addition to stable dispersion of proppant in fracturing fluid, can perform flexible viscosity control by further improving viscosity by crosslinking reaction, or decomposing after use to reduce viscosity of fluid it can. It is also possible to use it as a degradable antisoiling agent in fracturing fluid. By preventing the generation of mud, pressure can be easily applied in the pit, so that a better crack can be formed. If a conventional anti-smudging agent is added to the fracturing fluid, there is a risk of blocking the gas production flow path, but if the fibrous anti-soiling agent consisting of fibrous cellulose is decomposed after use, it will block the production flow path I have not.

(Cementing fluid)
An example of a fluid comprising the composition of the invention is a cementing fluid. The content of fibrous cellulose in the cementing fluid is not particularly limited as long as the intended effect is exhibited. The cementing fluid contains fibrous cellulose in solid concentration (as the total amount of fibrous cellulose), for example, 0.001 to 40% by mass, and preferably 0.01 to 20% by mass, preferably 0.05 to 5 It is more preferable to contain mass%.

  As cementing fluid, high temperature durable cement such as general purpose cement such as tricalcium silicate or class G cement used for high temperature well can be used. In order to optimize the cementing time, a caking agent such as a cement quick curing agent or a cement retarder can be used as an additive. In addition, cement dispersants, fluidity improvers, low specific gravity, low dewatering cement additives and the like can also be used. In addition, a dehydrating regulator, a strength stabilizer, a weighting agent, a cement spacer additive for improvement of substitution efficiency and for underground cleaning, a chemical wash additive for performing well surface cleaning, and the like can be added. In addition, cement slurry antifoaming agent, scale inhibitor, anti-smud agent, calcium aluminate, sodium polyphosphate, fly ash, foaming agent, foam stabilizer, and a sufficient amount of gas to form foam etc. It can also be done. The fluid may optionally include particles of inert, crushed rubber in order to provide elasticity to the cementing fluid upon curing.

  Fine fibrous cellulose forms a three-dimensional network in water, and even fine materials can be stably dispersed. For example, in cementing fluid, cement particles of 10 μm or less are present. The fine fibrous cellulose can be stably dispersed even in particles of 10 μm or less. In addition, hydrophobic particles can also be stably dispersed in water, and, for example, hydrophobically treated pigment particles, minerals and the like can also be stably dispersed. Further, since the fine fibrous cellulose is highly hydrophilic, it is possible to suppress the water separation of the cementing fluid. Since the salt resistance is also high, the compatibility with a cementing fluid containing a large amount of calcium is also good.

In addition, in high temperature wells containing carbon dioxide, such as geothermal wells, a cementing fluid that does not degrade in the presence of carbon dioxide containing saltwater is desired. Also, cement compositions used in geothermal wells and similar wells should be lightweight, for example, having a density in the range of about 9.5 to about 14 pounds per gallon (about 1.14 to about 1.68 g / cm ³ ) Is preferred. The cementing fluid of the present invention can also be configured to such a density range.

[Processing method of underground layer, production method of oil resource]
The present invention also provides a method of treating an underground formation, comprising treating the underground formation with the composition or fluid of the present invention. The underground layer (sometimes referred to as the stratum) also includes the bottom layer of the seabed.

  The treatment of the subterranean formation involves the drilling of wells used for various purposes. Wells may be exploratory wells or wildcat, evaluation wells (appraisal wells), exploration wells (exploratory wells or exploration wells), delineation wells, development wells, production wells, injection wells It includes, but is not limited to, injection wells, observation wells, service wells and the like.

In addition, the treatment of the underground layer includes the following.
Cementing: This is mainly done to fill the gap between the casing and the well wall with cement to fix the casing after digging the well.
・ Well investigation, well logging: This includes mud logging. Mud logs are used to observe and analyze gas and cuttings in circulating drilling mud, so that oil and gas reservoirs can be detected early and rock facies being drilled can be known.
-Recovery of petroleum resources: This includes water flooding, chemical flooding.
・ Well stimulation: The purpose is to improve the properties of reservoirs in and around wells and improve productivity. This includes washing with hydrochloric acid etc., acidizing, hydraulic fracturing, hydrofracturing, fracking to create a crack in the reservoir to secure the fluid flow path. Furthermore, in the case of production from the sand layer, the sand control (sand control), the fluid containing resin, etc. are undergrounded to prevent the inflow of sand into the well of the sand and the fluid containing the sand from damaging the tubing and equipment. The resin consolidation (plastic consolidation) etc. which press-fit in a layer and harden a sandstone are included.
• Well finishing with aqueous mud, oil based mud, chemical fluid or brine.
• Fracturing using high pressure fracturing fluid to create a passage (cracks, fractures) in a low permeability tight underground layer.
・ Well workover (well workover).
・ Abolished mine processing.

  The invention also provides a method of producing petroleum resources comprising treating an underground formation with the composition or fluid of the invention. Petroleum resources refer to all solid, liquid and gaseous mineral hydrocarbons present underground. Typical examples of petroleum resources are the general divisions liquid oil and gaseous natural gas. As petroleum resources, in addition to conventional petroleum (oil), natural gas, tight sand gas, shale oil, tight oil, heavy oil, super heavy oil, shale gas, coal bed gas, bitumen, heavy oil, oil Includes sand, oil shale and methane hydrate.

  The following examples illustrate the invention, but the scope of the invention is not limited by the examples. The compounding amount represents mass%.

<Measurement of freeness>
The freeness was measured in accordance with JIS P 8121.

<Calculation of lignin content>
The lignin content L was measured according to TAPPI / ANSI T 236, and was calculated from L (%) = Kappa number × 0.13.

<Measurement of Kappa number>
The Kappa number was measured in accordance with JIS P 8211. The products 1 and 2 were subjected to a test at a dry weight of 0.25 g, and the test results with Kappa number in the range of 5 to 100 were applied. However, 100 ml of potassium permanganate (0.2 mol / L) was used for the product 1. The correction factor for conversion to potassium permanganate 50% (mass / mass) consumption was 1.061 for the product 1 and 1.035 for the product 2 with reference to TAPPI / ANSI T 236.

<Production Example 1>
The wood chip which mixed 60 mass% of red pines and 40 mass% of larchs was used as a raw material wood chip.
The wood chips were crushed in a ball mill. The pulverized chips were diluted with ion exchange water to a concentration of 2% by mass, and then passed through a single disc refiner whose clearance was set to 50 μm five times to obtain a product 1. The freeness of this product was 219 ml, and the lignin content in the solid content was 21.7% by mass.

<Production Example 2>
To the product 1, 1.5 mass% caustic soda per bone dry mass was added, and subjected to oxygen exposure at an oxygen pressure of 0.75 MPa, a temperature of 100 ° C., and a time of 60 minutes. To the product after oxygen exposure, 0.8 mass% of chlorine dioxide per bone dry mass was added, and D0 stage treatment was performed at 60 ° C. for 60 minutes. The resulting product was diluted with water to a concentration of 3% by mass, then dehydrated and washed to a concentration of 10% by mass. Add 1.0% by mass of caustic soda, 0.3% by mass of hydrogen peroxide per bone dry mass to the product after D0 stage, pressurize with oxygen gas to 0.15MPa, E / OP stage at 70 ° C for 90 minutes I did the processing. The resulting product was diluted with water to a concentration of 3% by mass, then dehydrated and washed to a concentration of 10% by mass. 0.2% by mass of chlorine dioxide and 0.05% by mass of caustic soda were added to the product after the E / OP stage and D1 stage treatment was carried out at 70 ° C. for 180 minutes to obtain a product 2 . The freeness of this product 2 was 131 ml, and the lignin content in the solid content was 17.5% by mass.

<Production Example 3>
The wood chip which mixed 70 mass% of larchs, 25 mass% of Douglas fir, and 5 mass% of slash pine was used as a raw material wood chip.
This wood chip is infiltrated into a white liquor with a degree of sulfurization of 27% and an effective alkali of 10% in an infiltration tower for 1 hour at a liquid ratio of 4.0, and then in the digester using the same white liquor, the liquid ratio The kraft digestion was carried out for 5 hours at 5.0 and the digestion temperature of 150 ° C. After completion of the kraft digestion, the black liquor was separated, and the obtained chips were washed with a pressure diffuser and a diffusion washer, and then foreign matter and undegraded matter were removed by a screen.
The obtained digested product was subjected to a bleaching treatment in the same manner as in Production Example 1 to obtain a product 3. The freeness of this product was 764 ml, and the lignin content in the solid content was 0.52% by mass.

Production Example 4
Water was added to softwood bleached kraft pulp (manufactured by Oji F-TEX Co., Ltd., water 50% by mass, freeness 700 ml) to a concentration of 4% by mass. Then, use a double disc refiner to beat irregular freeness (flat weave 80 mesh, according to JIS P8121 except for the amount of pulp collected 0.3 g, 265 ml) and beat until the average fiber length becomes 0.66 mm. I got four. The freeness of this product was 28 ml and the lignin content in the solid was 0.39% by mass.

<Production Example 5>
A slurry of product 1 (concentration 3.5 wt%) is vacuum filtered and dewatered using a Buchner funnel and vacuum pump to produce 219 ml freeness and 21.7 wt% lignin content in solids The product 5 (concentration 17.5 mass%) was obtained.

<Production Example 6>
A slurry of product 2 (concentration 3.5% by weight) is vacuum filtered and dewatered using a Buchner funnel and a vacuum pump, producing 131 ml freeness and 17.5% by weight lignin content in solids The thing 6 (concentration 16 mass%) was obtained.

Production Example 7
The product 5 was dried using a dryer at 105 ° C. for 16 hours to obtain product 7 (concentration 100 mass%) having a freeness of 219 ml and a lignin content of 21.7 mass% in the solid content .

<Production Example 8>
The product 6 was dried using a drier at 105 ° C. for 16 hours to obtain product 8 (concentration 100 mass%) having a freeness of 131 ml and a lignin content of 17.5 mass% in the solid content .

<Production Example 9>
The product 6 was air dried at 22 ° C. for 5 days to obtain a product 9 (concentration 80.5 mass%) having a freeness of 131 ml and a lignin content of 17.5 mass% in the solid content.

Production Example 10
The product 3 was dried using a drier at 105 ° C. for 16 hours to obtain a product 10 (concentration 100 mass%) having a freeness of 764 ml and a lignin content of 0.52 mass% in the solid content .

<Production Example 11>
Wood chips derived from spruce pine were crushed by a Hadano Sangyo DD mill. The obtained ground product was dried at 105 ° C. for 16 hours using a drier to obtain 100% by mass of product 11. The freeness of this product was 550 ml, and the lignin content in the solid content was 26.8% by mass.

<Measurement of fiber width>
The fiber widths of the products 1 to 4 and the product 11 were measured by the following method.
It was diluted with water to a concentration of 0.01 to 0.1% by mass and dropped onto a hydrophilized carbon grid film. After drying, it was stained with uranyl acetate and observed with a transmission electron microscope (JEOL-2000EX, manufactured by JEOL Ltd.).
Moreover, it diluted with water to the density | concentration of 0.01-0.1 mass%, and dripped at the slide glass. A cover glass was put on and observed with a digital microscope (Hirox, KH-7700).

  From the above, it was confirmed that products 1 to 4 and product 11 contained fine fibrous cellulose having an average fiber width of 1000 nm or less. Moreover, the coarse fiber-like cellulose whose average fiber width is larger than 1 micrometer, and whose fiber length is 10 micrometers or more was also contained in the products 1-4 and the product 11. FIG.

Example 1
It was added to ion exchange water so that the final concentration of the product 2 (concentration 3.5 mass%) was 0.6 mass% and the final concentration of guar gum was 0.4 mass%. The mixture was stirred at 1400 rpm for 10 minutes using a disperser to prepare 120 g of a dispersion.
Example 2
A dispersion was prepared in the same manner as in Example 1 except that Product 1 (concentration 3.5% by mass) was used instead of Product 2.
Example 3
A dispersion was prepared in the same manner as in Example 1 except that the final concentration of guar gum was changed to 0.2% by mass.
Example 4
A dispersion was prepared in the same manner as in Example 1 except that the final concentration of guar gum was changed to 0.3% by mass.
Example 5
A dispersion was prepared in the same manner as in Example 1 except that the final concentration of guar gum was changed to 0.5% by mass.

Example 6
A dispersion was made in the same manner as Example 1, except using the product 6 instead of the product 2.
Example 7
A dispersion was prepared in the same manner as in Example 1 except that Product 5 was used instead of Product 2.
Example 8
A dispersion was made in the same manner as Example 1 except using the product 8 instead of the product 2.
Example 9
A dispersion was prepared in the same manner as in Example 1 except that Product 7 was used instead of Product 2.
Example 10
A dispersion was prepared in the same manner as in Example 1 except that Product 9 was used instead of Product 2.
Example 11
A dispersion was prepared in the same manner as in Example 1 except that xanthan gum was used instead of guar gum.

Comparative Example 1
A dispersion was prepared in the same manner as in Example 1 except that no guar gum was added.
Comparative Example 2
A dispersion was prepared in the same manner as in Example 2 except that no guar gum was added.
Comparative Example 3
A dispersion was prepared in the same manner as in Example 8 except that no guar gum was added.
Comparative Example 4
A dispersion was prepared in the same manner as Example 9, except that no guar gum was added.
Comparative Example 5
A dispersion was prepared in the same manner as in Example 10 except that no guar gum was added.

Comparative Example 6
A dispersion was prepared in the same manner as in Example 1 except that the product 2 was not added.
Comparative Example 7
A dispersion was prepared in the same manner as in Example 11 except that the product 2 was not added.
Comparative Example 8
A dispersion was prepared in the same manner as in Example 1 except that Product 4 (concentration 3.5% by mass) was used instead of Product 2.
Comparative Example 9
A dispersion was prepared in the same manner as in Comparative Example 8 except that no guar gum was added.
Comparative Example 10
A dispersion was prepared in the same manner as in Example 1 except that Product 3 (concentration 12.5% by mass) was used instead of Product 2.

Comparative Example 11
A dispersion was prepared in the same manner as Comparative Example 10 except that no guar gum was added.
Comparative Example 12
A dispersion was made in the same manner as Example 1, except that the product 10 was used instead of the product 2.
Comparative Example 13
A dispersion was prepared in the same manner as in Comparative Example 12 except that no guar gum was added.
Comparative Example 14
A dispersion was prepared in the same manner as in Example 1 except that Product 11 was used instead of Product 2.
Comparative Example 15
A dispersion was prepared in the same manner as in Comparative Example 14 except that no guar gum was added.

<Evaluation>
The viscosities of the dispersions of Examples 1 to 11 and Comparative Examples 1 to 15 were measured by the following method. The particle dispersibility of the dispersions of Examples 1 to 11 and Comparative Examples 1 to 15 was evaluated based on the following criteria. The results are shown in Table 1.

(Measurement of viscosity)
The viscosity of the aqueous solution after dispersion was measured by rotating for 3 minutes at a rotational speed of 3 rpm at 25 ° C. using a B-type viscometer (analog viscometer T-LVT, manufactured by BLOOK FIELD).
The unit of viscosity is mPa · S.

(Evaluation of particle dispersibility)
100 g of the prepared dispersion was taken, and 10 g of proppant (for example, Bauxite 40/80 manufactured by SINTEX Corporation) was added to prepare a proppant dispersion stirred for 1 minute. The prepared proppant dispersion was placed in a 100 ml volumetric cylinder, and the scale of the graduated cylinder on which the top of the proppant dispersion was located (hereinafter referred to as "scale before standing") was read and then allowed to stand for 1 hour. Later, the scale of the measuring cylinder on which the top of the proppant is located (hereinafter referred to as "scale after standing") was read. The scale was read by setting the scale of the uppermost end of the measuring cylinder before settling to 0 ml and the scale of the lower end of the measuring cylinder to 100 ml. The particle dispersibility was evaluated from the value of the scale according to the following criteria. The particle dispersibility can be said to be better as the scale after stationary is smaller. With the composition of the present invention, particle dispersibility can be less than 70 ml. In a preferred embodiment it may be less than 55 ml and in a further preferred embodiment it may be less than 40 ml.

Evaluation criteria:
:: scale after standing is less than 40 ml ○: scale after standing is 40 ml or more and less than 55 ml Δ: scale after standing is 55 ml or more and less than 70 ml ×: scale after standing is 70 ml or more

  As shown in the examples, the composition containing wood fiber and water-soluble polymer mechanically fibrillated had high viscosity and particle dispersibility as a thickener. In particular, the viscosities obtained in Examples 1 and 11 were simply the viscosities of the composition alone and higher than the combined viscosities, and it was shown that a suitable lignin content exerts an excellent synergetic effect. . Although Examples 6-10 included the drying process, it was shown that a big difference can not be confirmed in a result and this method is applicable also to dried material.

  Comparative Examples 8 and 9 have a very good water familiarity, as can be seen from the low freeness of the product. Also, it contains almost no lignin. Therefore, a strong hydrogen bond is formed between water and the fiber, and the water-soluble polymer can not be properly dispersed in the vicinity of the wood fiber, and the particle dispersibility is not exhibited due to aggregation.

  In Comparative Examples 10 to 13, as can be seen from the high degree of freeness of the product, the water compatibility is poor and lignin is hardly contained. Therefore, a strong hydrogen bond between the fibrous cellulose causes the wood fiber to partially condense, thereby preventing the formation of a hydrogen bond with the water-soluble polymer. Therefore, the particle dispersibility was not exhibited for the viscosity.

  In Comparative Examples 14 and 15, the freeness of the product is high, and as can be seen from the high lignin content, they are hydrophobic and hydrogen bonds with the water-soluble polymer are less likely to be formed. In addition, the viscosity and the particle dispersibility were low because they were not very compatible with water.

Claims (16)

A composition comprising (a) wood fibers having a freeness of 50 to 300 and a lignin content of 10 to 25% by mass in the solid content, (b) a water-soluble polymer, and (c) a solvent . (A) wood fibers having a freeness of 50 to 300 and a lignin content of 5 to 25% by mass in the solid content, (b) a water-soluble polymer, and (c) a solvent; Composition to be used as a thickener . (A) wood fibers having a freeness of 50 to 300 and a lignin content of 5 to 25% by mass in the solid content, (b) a water-soluble polymer, and (c) a solvent; The composition which is a composition for layer treatment . The composition according to any one of claims 1 to 3 , wherein the wood fibers comprise at least fibrous cellulose. The composition according to any one of claims 1 to 4, wherein the solid content concentration of wood fiber is 0.2% by mass or more and 1% by mass or less. The composition according to any one of claims 1 to 5 , wherein the water-soluble polymer is a nonionic polymer. The composition according to any one of claims 1 to 6 , wherein the water soluble polymer is a natural polysaccharide. The composition according to any one of claims 1 to 7 , wherein the solid content concentration of the water-soluble polymer is 0.1% by mass or more and 1% by mass or less. The solvent is water, the composition according to any one of claims 1 to 8. 10. The composition according to any one of claims 1 and 3 to 9 for use as a thickener. The composition according to any one of claims 1 , 2 and 4 to 10, which is a composition for treating underground formation. A method of treating an underground formation, comprising treating the underground formation with the composition according to claim 3 or 11 . A method of producing petroleum resources comprising treating an underground formation with the composition according to claim 3 or 11 . The process according to any one of claims 1 to 11 , comprising the steps of concentrating or drying the wood fiber dispersion, and redispersing the obtained concentrate or dried product and the water-soluble polymer in a solvent to obtain a redispersion liquid. The manufacturing method of the composition as described in a term. The process according to any one of claims 1 to 11 , comprising the steps of concentrating or drying a dispersion containing wood fibers and a water-soluble polymer, and redispersing the obtained concentrate or dried product in a solvent to obtain a redispersion. The manufacturing method of the composition as described in one term. The production method according to claim 14 or 15 , wherein the concentration is performed by any of a concentration agent, a dryer, or a filter dehydration.