DD159443A1 - METHOD FOR PRODUCING AN INJECTION MIXTURE FOR SALT GRAINS - Google Patents

Abstract

The invention relates to a method for producing an injection mixture for sealing and solidifying in mining, in particular in potash and rock salt mining, by means of Magnesiabinder and MgCl deep 2 or MgSO deep 4-solution. The invention aims to produce an injection mixture characterized by controllable reaction times, low viscosity, excellent flow properties, pumpability and stability of the mixture. It was found that the addition of slate meal in the fraction up to 0.04 mm in amounts up to 60% to the proportion of magnesia binder meets these requirements.

Description

The invention relates to a method for producing a hardening injection mixture for salt rocks.

c) Characteristic of the known technical solutions

In order to seal against saline inflows and to solidify tectonic fault zones as well as otherwise stressed mountain sections in potash and rock salt mining, the selection of a suitable mortar for an injection mixture is very difficult. Cement suspensions are excreted as a binder component since the cement corrodes upon contact with saline solutions. Plastic mixtures such as e.g. Polyurethane, urea-formaldehyde glue do not meet all safety and quality requirements for injections in salt mining and are also very expensive.

The use of the known magnesium oxide chloride (sulfate) binder as injection mixture for salt rocks would be a great advantage for potash mining, since virtually the second binder component (MgCl ₀ - or MgSCL solution) is partially underground in potash mining , But alone can with the binding components

- Й JUN. 1981 -: = ί.) Я ί) 7

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MgO - MgCl ₂ J MgSO ₂ - H ₂ O without additive no effect can be achieved.

It has already been described that Sorelbinder are not resistant to saline solutions containing MgSO.-portions. Their hardening time is not adjustable, and exothermic reactions cause cracks in the compressed injection mixture. It is therefore proposed the addition of ammonium salts and aminoplasts. However, this injection mixture has not attained a practical significance since, apart from economic considerations, the mentioned objectives of the invention are not achieved in the practical injection-molding operation.

The use of injection mixtures, especially in coal mining, has hardened to solidify the coal collisions, which are produced from MgO, MgGl ₂ solution and bentonite. The bentonite supplement can be up to 25 % . The Bentonitzusatz should be effective especially in the dispersion phase by controlling the setting process stabilizing and beyond the dispersion transmits the typical of its montmorillonite share the many clays thixotropic property.

Contrary to expectations, the bentonite does not behave chemically inert to the salt solutions produced in potash mining. The always present in these salt solutions SO ^, - percentage reacts with the equivalent Oa ⁺⁺ -Between lattice ion ~ of the bentonite is substantially constituting montmorillonite "It will CaSO ^ H ₂ O (gypsum), CaSO ^ 1/2 HPO.. (Halibhi / drat) and silicic acid are formed, so that this is due to the dissolution of the indium-trillonillonite content, that is, under the conditions of potash mining a bentonite dissolution occurs.

d) Object of the invention

The aim of the invention is to produce an injection mixture characterized by controllable reaction times, low viscosity, excellent flow properties, adhesion with the salt rocks, optimum processing properties (PiwipfcihiGke.it) stability of the mixture

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and safe handling.

e) Presentation of the essence of the invention

The invention has for its object to produce a hardening injection mixture for sealing against saline inflow and for solidifying tectonic fault zones and otherwise claimed mountain sections, which fully meets the requirements of potash mining.

It has been found that by the addition of slate flour, preferably in the fraction - o, o4 ram, in amounts up to 6o % to Magnesiabinderanteil meets these requirements surprisingly full.

The saline solutions in the potash production with 1oo g / l MgClI or MgSOb contents <1oo g / l can be used as second binder to the magnesia binder. Depending on the desired strength values in the hardening injection mixture, MgGl ₂ .6H ₂ O must additionally be added to the mixing liquid. In detail, there are the following advantages with slate meal addition compared to the previously used Injektionsniischungen including bentonite additives. With the addition of slate flour, a homogeneous, stable, well pumpable mortar is achieved and thus a "loop-filling of the cavities in the mountains reached, in which the suspension is able to penetrate due to the size of the largest grain." With the use of MgO slate flour salt solution suspension there ^has been a reduction in the required Verproßdruckes by about 5 °% This set the stage for an increase in the injection range when exploiting the maximum are;. Ve-rpreßdruckes created.

Due to the high proportion of illite and kaolinite in shale meal, resistance to the presence of MgSO 3 -containing salt solutions is achieved for the first time, and this results in the universile application of this injection mixture in potash and rock salt mining.

230639

The pumpability of the mixture is doubled. With the addition of slate flour, the shrinkage and swelling phenomena of the MgO mortars are lower, the adhesion of the MgO mortar in the upcoming salt rock is further improved.

The invention will be explained in more detail in the following embodiments.

embodiment

mixture

mix recipe

ivIgO Sa Izlsg.

/ kg / / 1 /

additive

/ Kg /

g .H ₂ (T.

/ Kg /

mixing ratio

MgO: additive

g ₀ ; 6H ₂ O; Salztösuns

Sorelbindermisch. without additive Ъ zw. Ar ₁ In onium chloride-glaze.

33

11

: 0: o, 33

Sorelbindermisch ·; ' with Bentcnitzusatz -glitter mix. 27 25 6 11 1: о , 22; , 52 o, 93 Sorelbindermisch. m.Schiefermehl- addition 21 '25 12 11 1: о ^ 7 : : 1.19 : о : о

Composition of saline solution

64 g MgSCL / 1 113 S MgClp / 1

84 g KG1 / 1 133 S NaC1 / 1 876 g H ₂ 0 / l

CT) CO

mixture

Properties d. Injek .tionsrai sling

• l) r uc kfestig-кеіѣ V

± ^J ump-

able to-

ness

/ min / homogeneity d. VIvIi s с hung

Resistance to upcoming saline , esp. MgSO 4 solution.

Vexpxeßdruck

SoreIbindermisch «without additive or Aairnoniumchlorid -glerr.-mix.

32

53 Separations Strengthening of strength approx. 5 min. Cracks in the spiked mixture

I like it. 8o % strong Koxxosionseischeinungen, Eißbildungen

high pressure, low injection accuracy

Soxeibindermisch «with bentonite additive

20

76 mortar. Stability level remains stable, loss about 80 %, no strong corrosion. social phenomena

average pressure, medium injection range

tears, cracks

Sorelbinder mix · m.Schiefermehlzusatz

135 mortar mix stays stable

no signs of corrosion and cracking loss of strength 5 - 1o%

low injection pressure, large injection range (2-3 times)

Claims (3)

1. A process for the preparation of an injection mixture for salt rocks for sealing and solidifying in mining, in particular in potash and rock salt mining, by means of Magnesiabinder and MgCl ₂ or, MgSO _{Z |} ~ Solution _/ characterized in that slate meal, preferably in the fraction <o, o4 mm, is added to the magnesia binder mixture, the slate meal being up to about 60% of the fraction of magnesia binder. 2. A method for producing a salt rock injection mixture according to item 1 _; characterized in that the slate meal is preferably composed of ₄ the clay minerals illite and kaolinite. 3. A process for preparing an injection mixture for salt rocks according to item 1, characterized in that the saline solutions in potash mining are used as Anmachflüssigkeit and contained in them MgCl ₂ - and MgSO ^ - contents as a second binder component, the Magnesiabinder.