RU2358930C1 - Mineral binder - Google Patents

Abstract

FIELD: construction.

SUBSTANCE: invention may be used in monolithic erection of building structures - walls, partitions, ceilings, coatings, to produce small-item products, and also to produce dry construction mixes on its basis. Mineral binder includes the following components, wt %: gypsum 50 - 99.5, sugar mud - waste of sugar production with calcite content of 60 - 85% and size particle of less than 50 mcm - 0.5-50.

EFFECT: increased time required for setting of mineral binder.

2 ex, 2 tbl

Description

The invention relates to compositions of binders and can be used in monolithic construction of buildings - walls, partitions, ceilings, coatings, for the manufacture of small items, as well as for the manufacture of dry building mixtures on its basis.

When working with gypsum binders and mixtures based on them, there is a problem of increasing the setting time, which exists at present.

The composition of the gypsum binder is known, where in addition to semi-aquatic gypsum, an addition of finely ground limestone in an amount of 50 to 100% to semi-aquatic gypsum is introduced, which increases the onset of setting from 7.5 minutes to 12 minutes and the end of setting from 11 minutes to 16 minutes (ed. No. 73705, CL 80b, 6 ₀₁ , publ. 01/31/1949), which is taken as a prototype.

However, this composition has an insufficient increase in the interval of the beginning and end of setting for work with it on monolithic castings in building conditions, in addition, the high-strength gypsum used in the composition is expensive for its use in conventional partitions, walls, coating structures, in public internal works.

The technical result to which the claimed invention is directed is to increase the setting time of the mineral binder.

To achieve the technical result, a mineral binder, including gypsum and an additive, contains defecate as an additive, which is a waste from sugar production with a calcite content of 60-85% and a particle size of less than 50 microns, with the following ratio of components, wt.%: Gypsum 50- 99.5, defecate 0.5-50.

As a result of the introduction of a defect, which is a waste product of sugar production with a calcite content of 60-85% and a particle size of less than 50 microns, into the mineral binder as a additive, setting times increased from 10 to 35 times.

The micron sizes of calcite in the defecate are due to the technology of purification of sugar syrup with lime test and its subsequent conversion back to calcite by blowing the solution of sugar syrup with carbon dioxide. In this case, sugar syrup is the interface between the crystals of calcite and organic plant particles, preventing their aggregation and fusion.

Using defecate as a raw material for building products will allow sugar factories to free themselves from production waste.

To select the binder composition, quick-setting (in accordance with GOST 125-79) gypsum of the G-6 grade of the Arakchinsky plant of the Republic of Tatarstan is used with the following setting periods, the start of setting is 3-4 minutes, the end is 10 minutes, as well as normally hardening gypsum of the G-6 grade of the Volgograd plant with the beginning setting 13.5 minutes and the end of setting 17.5 minutes.

As an additive, powdered defecate of the Buinsky sugar plant of the Republic of Tatarstan is used with a content of 70-75% calcite, an initial moisture content of 25%, and a particle size of less than 50 microns.

The procedure for the following two examples was as follows: first, the entire volume of water is poured into the high-speed mixer, in which all defecate is dissolved with stirring for 0.5-1.0 minutes, then gradually the entire volume of gypsum is poured into the mixture with the mixer running, then mix for 1-1.5 minutes and get an astringent.

Example 1

To select the composition of the mineral binder, gypsum of the G-6 grade of the Arakchinsky plant of the Republic of Tatarstan, defect of the Buinsky sugar plant with an initial moisture content of 25%, with an average calcite content of 60-85% are used.

The selection of the composition consists in preliminary standard selection of the water-solid ratio for each binder composition, determination of the normal binder density, followed by determination of the setting time, production of samples in the form of standard rolls and their bending and compression tests according to GOST 23789-79 Gypsum gypsum binders. Test methods.

The binder raw mix is obtained by pre-mixing the defecate with water, followed by the addition of gypsum and in the ratio of gypsum: defecate equal to 99.5: 0.5, 98: 2, 95: 5, 90:10, 80:20, 70:30, 60:40, 50:50, 40:60.

Table 1 Indicators Gypsum G-6 of the Arakchinsky plant RT + defecate with a moisture content of 25% (compositions), wt.% 100: 0 99.5: 0.5 98: 2 95: 5 90:10 80:20 70:30 60:40 50:50 40:60 Water solid ratio 0.58 0.58 0.58 0.57 0.55 0.52 0.5 0.49 0.48 0.6 Setting start 3 5 8 12 twenty 27 33 61 106 281 End of setting (minutes) 10 12 fifteen 21 35 fifty 59 98 194 - Compressive strength after 2 hours (kg / cm ² ) 60 59 55 51 36.6 33 21 5.3 Compressive strength after 7 days (kg / cm ² ) 130 129 126 110 86 70 45 27 23 12 Bending strength after 2 hours (kg / cm ² ) 31 31 thirty 29th 23.8 18.2 13 5,6 Bending strength after 7 days (kg / cm ² ) 54 54 53 51 49 38.9 27 14.2 9.9 7.1

From the above data in table 1 it is seen that when introducing into the composition of the binder defecate in an amount of from 0.5% to 60%, an increase in the setting time is observed. In accordance with the provisions of GOST 125-79, the type of the initial gypsum of the Arakchinsky plant is quick-hardening with the start of setting 3 minutes and the end of 10 minutes, when 5% defecate is introduced into the initial gypsum, the type of binder changes to normal-hardening, and when defecate is introduced 10% or more, the type of binder becomes slowly hardening with the start of setting from 20 minutes or more.

Example 2

It is carried out according to example 1, with the difference that normally-hardening gypsum of the G-6 grade of the Volgograd plant with the following setting periods is used to obtain the raw mix: the beginning of setting is 13.5 minutes, the end is 17.5 minutes.

The compositions and physico-technical characteristics are shown in table 2.

table 2 Indicators Gypsum G-6 of the Volgograd plant + defecate with a moisture content of 25% (compositions), wt.% 100: 0 99.5: 0.5 98: 2 95: 5 90:10 80:20 70:30 60:40 50:50 40:60 Water solid ratio 0.52 0.52 0.52 0.51 0.51 0.48 0.47 0.46 0.46 0.58 Setting start 13.5 14.1 14.1 18.0 24.5 31.5 44.0 61.5 126.5 300 End of setting (minutes) 17.5 18.2 18.2 24.5 36.0 57.0 75.0 110.5 208.0 - Compressive strength after 2 hours (kg / cm ² ) 61.0 60.0 50,5 fifty 38.7 31.6 20,4 5.2 - - Compressive strength after 7 days (kg / cm ² ) 154.8 152.0 150.2 141.6 123.6 105.8 63.8 44.6 29.6 22 Bending strength after 2 hours (kg / cm ² ) 34.1 34.0 33.9 32,3 26,4 19.9 14.3 5,4 - - Bending strength after 7 days (kg / cm ² ) 52.3 50.1 46,4 45.7 43,4 thirty 18.7 11.1 5.8

When 10% defecate is introduced into the initial gypsum, the type of binder changes to slow hardening, with the onset of setting of 20 minutes or more.

When more than 50% of the defect is introduced into gypsum (both the Arakchinsky and Volgograd plants), the water demand increases, water separation is observed, and compressive and bending strength decrease. Finished products with a gypsum: defecate ratio of 70-99.5: 0.5-30 have physical and technical characteristics that meet GOST 125-79, a binder grade from G2 to G6 and 3-4 times longer setting times according to compared with the prototype, and compositions with a gypsum: defecate ratio of 60-50: 40-50 have a setting time of more than 60 minutes and an end of setting of more than 90 minutes and are suitable for the manufacture of dry building mixtures based on them (see tables 1 and 2 )

Field tests of the proposed mineral binder were carried out during the monolithic manufacture of interior partitions. A mixture of a binder, consisting of 70% Arakchinsky gypsum of grade G-6 and 30% defect of Buinsky sugar factory with a water-hard ratio of 0.5 and the start of setting, 36 minutes, and the end of setting 65 minutes, was mixed in a high-speed mixer for 5 minutes, loading the mixer was carried out in the following sequence: first, water and defecate were loaded, followed by gypsum. The prepared binder with a gerotor pump was supplied through hoses to the mounted formwork of the interior partitions. Three hours later, the formwork was dismantled. The resulting partitions had a flat front surface and compressive strength of more than 20 kg / cm ² .

Thus, the proposed mineral binder allows you to increase the setting time by 10-35 times, depending on the brand of gypsum and its deposits.

Claims (1)

Mineral binder, including gypsum and an additive, characterized in that it contains defecate as an additive - sugar production waste with a calcite content of 60-85% and a particle size of less than 50 microns in the following ratio of components, wt.%:
gypsum 50-99.5 defecate 0.5-50