JPS63264695A - Mud conditioner - Google Patents

Abstract

PURPOSE:To provide a mud conditioner which exhibits excellent flowability and viscosity in civil engineering works, such as excavation, and boring, and exhibits excellent blending rate when used in a cement milk and which comprises a powder of a particular swellable clay and, mixed therewith, a powder of a mineral other than the clay. CONSTITUTION:5-35pts.wt. powder of a swellable clay (A) mainly composed of montrorillonite having exchangeable cations at least 50% of which are an alkali metal, which powder completely passes a 60-mesh sieve, pref. a 200-mesh sieve is mixed with 95-65pts.wt. powder of a mineral (B) other than component (A), pref. a silicate salt, selected from among olivine, garnet, augite, mica, feldspar and quartz, thereby preparing a mud condition. 100 pts.wt. mud conditioner is mixed with 400-8,000pts.wt. water, thereby preparing a liq. mud.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a mud conditioning material for preparing muddy water used during drilling and excavation in civil engineering works.

(Conventional technology) When excavating deep holes during construction and civil engineering work,
In order to prevent the collapse of the borehole due to seepage of groundwater or oil spillage, muddy water containing bentonite or bentonite and carboxymethylcellulose as its main components is prepared.
This has been injected into holes and then drilled and excavated.

In normal civil engineering work, once a hole of a predetermined depth and shape has been excavated, reinforcing bars, etc. are inserted into the hole, and in order to fix it, muddy water and cement milk are replaced, and foundation work for buildings, etc. is carried out. In some cases, muddy water is removed and excavated soil is backfilled. Furthermore, recently, when using the shape of an excavated hole to form the foundation of a building, it has become common practice to prepare cement milk using muddy water filled in the excavated hole and solidify it to make foundation piles, etc. became. This method not only prevents the generation of waste mud, which has traditionally been difficult to dispose of, but also shortens the construction period for foundation work.

However, when cement is added to muddy water to prepare cement milk using the muddy water and cement, the presence of algae in the milk inhibits the solidification of the milk, so it is recommended to use bentonite for muddy water preparation. Conventionally, it has been difficult to prepare muddy water with good fluidity, high viscosity, and excellent dispersibility unless this bentonite is used.

In addition, according to the research of the present inventors, in cement milk prepared by mixing cement and muddy water, so-called brie sink (the amount of free water due to sedimentation of suspended particles in milk)
It has been confirmed that bentonite is an indispensable material for reducing I).

(Problems to be Solved by the Invention) However, in the case of bentonite, there have been cases in which it has a significantly negative effect on promoting the initial solidification of cement milk, resulting in only a solidified product having low strength. That is, when attempting to prepare bentonite-cement slurry and obtain a solidified product by adding cement to the muddy water used for drilling after drilling using muddy water containing bentonite as a main component, bentonite This delays or inhibits the solidification of the cement slurry, making it difficult to obtain a high-strength solidified product within a predetermined period of time.

It is therefore an object of the present invention to provide a material for the preparation of muds which overcomes the drawbacks of conventional bentonite-containing muds mentioned above.

In other words, the purpose of the tree is civil engineering such as excavation and perforation! For example, when cement milk is made by adding a solidifying agent such as ordinary cement to muddy water, the suspension of cement milk is To provide a material for muddy water that can prevent settling of particles, that is, lower the rate of breathing, and can provide sufficiently satisfactory strength and sturdiness of the solidified product obtained when the cement milk is hardened. There is a particular thing.

(Means for Solving the Problems) The present inventors have conducted intensive research to obtain a material for muddy water containing bentonite having the above-mentioned functions. The difference in the content and the content in the mineral components of the swellable clay containing montmorillonite. The present invention was made based on this knowledge, which was found to have a large effect on strength.

That is, the present invention provides a powder 5 of a swellable clay whose main component is montmorillonite (hereinafter simply referred to as alkali metal type montmorillonite), which is an exchangeable cation or an alkali metal.
~35 parts by weight of mineral powder other than the swelling clay 95 parts by weight
The object of the present invention is to provide a mud conditioning material for civil engineering work, characterized in that it contains ~65 parts by weight.

In the present invention, alkali metal type montmorillonite refers to clay mineral montmorillonite in which the interlayer exchangeable cations are substantially alkali metal ions. Here, "substantially" is expressed in equivalents, and the exchangeable cations are 50 of
% or more is an alkali metal ion, preferably 65% or more. In the present invention, the cation is an alkali metal (sodium, potassium, lithium, etc.) because alkali metal type montmorillonite has a remarkable swelling power for wood. Larger, when swollen 2g in water, 45 rubs or more
This is because it occupies a volume of . Such montmorillonites, such as sodium-type montmorillonite, are usually contained in natural swelling clays, so to obtain highly pure montmorillonites, the swelling clays are dispersed in water and the density is increased by natural sedimentation or centrifugation. In the present invention, such high-purity sodium-type montmorillonite may be used, but the above-mentioned swellable clay containing sodium-type montmorillonite may be used as it is. In the latter case, the active ingredient in the swellable clay is preferably present in an amount of at least 30311% by weight.

Such swellable clay whose main component is alkali metal type montmorillonite is usually in powder form, more preferably in fine powder form, and in reality it is 60 mesh (Tyler standard sieve: the same applies hereinafter), preferably 150 mesh or 200 mesh. The powder is crushed and classified so as to completely pass through the sieve.To obtain such powder, ordinary crushers such as impact crushers, edge runners, ball mills, ring roller mills, and impact crushers can be used. On the other hand, the means for classification is not particularly limited as long as it is possible to classify dry powder, such as a gravity classifier,
Inertial classifiers, centrifugal classifiers, etc. are used. Note that when natural clay is used as a starting material, the final product often contains unnecessary moisture, so it is necessary to add a drying step to the processing methods described above. By appropriately combining these, it is possible to collect the desired fine powder.

Next, in the present invention, the mineral used to be blended into the above-mentioned swelling clay is not particularly limited as long as it is other than the above-mentioned swelling clay with a remarkable swelling power in water. Examples of minerals include olivine, garnet, pyroxene, amphibole, cloud f4, feldspar, and quartz. Those containing such minerals may be produced in the form of igneous rocks, metamorphic rocks, or sedimentary rocks; therefore, rocks such as basalt, andesite, granite, sandstone, slate, tuff 1 shale, etc. can be used. . W4 substances other than silicates,
For example, carbonates and sulfates of calcite, dolomite, gypsum, etc. may be used. In the present invention, these minerals are used in the form of powder, so it is preferable to use minerals that are easy to crush or powdered. Clays with low swelling power in water, such as calcium-type bentonite and diatomaceous earth, are preferred.

It is preferable to use china clay, acid clay, etc.

In addition to the above-mentioned naturally occurring minerals, the materials used in the present invention also include minerals obtained by incineration of ores or artificially produced, such as fly ash, gypsum from flue gas desulfurization, and blast furnace slag.

In the present invention, these materials are also used in powder form, preferably fine powder, but it is preferable that the particle size is the same as that of the above-mentioned swelling clay (alkali metal type montmorillonite) to be mixed. The material also needs to be subjected to processing such as drying, pulverization, and classification, but this is carried out according to the method described above.

In the present invention, the mixing ratio of the swellable clay powder containing alkali metal type montmorillonite as a main component and the mineral powder to be mixed therein is 5 to 35% by weight of the swellable clay in the mixed powder. Preferably 7~
The content shall be 20% by weight.

If the blending ratio of swelling clay is less than 5%, the viscosity will generally be low when preparing muddy water, poor film-forming properties will be obtained, and breathing of suspended particles will be prevented when making TI4 cement milk. On the other hand, if the blending ratio of swelling clay exceeds 35%, the above-mentioned properties as slurry will be improved overall, but the strength of the solidified product obtained by preparing cement milk will decrease. This is not preferable because it leads to a significant decrease in

The only way to uniformly mix the two types of powder in the above mixing ratio is to crush, dry, and classify each powder separately, measure out the predetermined amount of powder, and mix using a mixer. However, in this case, two processing systems are required prior to mixing, or the processing time becomes longer due to repeated use of one system. Another method is to mix a predetermined amount of both before starting processing or during the processing process, and to perform subsequent processing steps at the same time, thereby simplifying the processing.

The method of using the powdered mud-conditioning material of the present invention as mud water is not particularly different from that of conventional mud-conditioning materials.

For example, for 100 parts by weight of this muddy water material, 400 to 800 parts
0FIJ: You can add water from Okibe and use muddy water.

(Effects of the Invention) The mud preparation material of the present invention exhibits a satisfactory breathing rate even when mud is prepared and used as mud, and then cement is added to the mud and used for cement milk.

The solidified product exhibits much higher solidification strength than when using conventional materials for muddy water made of bentonite. Moreover, it exhibits appropriate fluidity, viscosity, and film-forming properties even as muddy water. Therefore, the mud preparation material of the present invention is much easier to handle and has superior functionality compared to conventional muddy water preparation materials.

(Example) Next, the present invention will be explained in more detail with reference to Examples.

Example 1 Southern limit bentonite (moisture content 6.5%, apparent specific gravity 0.6
5.250 mesh under 95.0%, swelling power 21/2g, montmorillonite content 56%, of which 88% is sodium type montmorillonite. Hereinafter, it will be referred to as bentonite A. ) and fly ash discharged from coal-fired power plants (92% of 150 mash)
were weighed in the proportions shown in Table 1 and mixed using a rotary evaporator (manufactured by Shibata Chemical Industry Co., Ltd.) to prepare five types of bentonite-fly ash muddy water preparation materials.

Next, 100 g of each of these materials was poured into 4000 g of water and vigorously stirred for 20 minutes.

Next, add 2000g of ordinary Portland cement,
The mixture was further stirred vigorously for 20 minutes to prepare a uniform muddy water-cement slurry. A portion of the slurry thus obtained was poured into a free sink bag according to the Japan Society of Civil Engineers standards, and the breathing rate was determined by dividing the amount of separated water after 24 hours by the amount of slurry poured. On the other hand, the remaining slurry was poured into a vinyl chloride pipe with a diameter of 15 cm, and after curing in water at 24 hours IL + 20''C, the solidified material was removed from the mold and the penetration resistance value was determined using the method of JIS A6204. It was measured.

The results are shown in Table 1.

As is clear from the if table, the content of bentonite A or O
In the case of (Experiment No. 5), the penetration resistance of the solidified material was extremely high, but the breathing rate was also extremely high, and the apparent viscosity for use as muddy water was low, making it impractical. On the other hand, those with bentonite A content of 50% by weight or more (
Does experiment number 1.2.3) improve the breathing rate?

The solidified material became difficult to solidify, and the penetration resistance value became significantly lower. Compared to these, the case of the present invention material (experiment number 4) containing 25ffi amount of bentonite A.

Both the breathing rate and the penetration resistance value are good. Furthermore, the muddy water of Experiment No. 4 had a high apparent viscosity and excellent film-forming properties peculiar to bentonite.

Example 2 The same experiment as in Example 1 was carried out, except that instead of the fly ash in Example 1, 200 mesh under powder obtained by crushing and drying shale produced in Oe Town, Nishimurayama District, Yamagata Prefecture was used. went. The results at this time are shown in Table 2.

As shown in Table 2, Experiment No. 4 had excellent fleecing properties and I' [ingress resistance]. The muddy water of Experiment No. 4 had a high apparent viscosity and high film-forming properties.

Example 3 Commercially available bentonite (moisture content 8.5%, apparent specific gravity 0.65°, 250 mesh under 78.2%, 111 moisture content ml/2g, calcium type) was used instead of the fly ash in Example 1. In bentonite, 75% or more of montmorillonite is calcium type.Hereinafter, it is referred to as bentonite B.

) was used, but the same experiment as in Example 1 was conducted.

The results are shown in Table 3.

As is clear from the results in Table 3, bentonite A alone has a significantly low penetration resistance value and is completely unusable (experiment number l), whereas experiment number 3 has a low breathing rate and penetration resistance. The value also showed a sufficiently high value. Further, as in Experiment No. 4 of Example 1, the muddy water in this case also had a high apparent viscosity and excellent film-forming properties.

Example 4 In Example 2, an experiment was conducted in exactly the same manner as in Example 2, except that the mixing ratio of the muddy water preparation material was changed. Measurements were also carried out after standing for 7 days. The results are shown in Table 4.

As shown in Table 4, the present invention material 1 <Experiment number 2,
In the case of 3), the resistance value is high.In particular, the penetration resistance value is increased by the oral process, indicating that sufficient solidification strength can be obtained.

Claims (1)

[Claims] It is characterized by containing 95 to 65 parts by weight of a powder of a mineral other than the swelling clay to 5 to 35 parts by weight of a powder of a swelling clay whose main component is montmorillonite whose exchangeable cation is an alkali metal. A mud-conditioning material.