RU2250883C2 - Binder for production of radiation-protective materials - Google Patents

Abstract

FIELD: sulfur binders used for manufacture of sulfur concrete for protection against radiation and filling seams of linings, equipment and building structures working under conditions of ionizing radiation.

SUBSTANCE: proposed binder contains, mass-%: sulfur, 45.75-46.49; baryta at specific surface of 250 sq m/kg and average density of 4350 kg/m, 51.96-52.8; reinforcing additive (asbestos fiber), 0.23-1.83; modifying additive (paraffin), 0.46-0.47.

EFFECT: enhanced radiation protective properties of binder.

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Description

The invention relates to compositions of sulfur binders and can be used for the manufacture of sulfur concrete, intended for protection against radiation, as well as for pouring the joints of the lining, equipment and building structures, operating under conditions of exposure to ionizing radiation.

A known composition for the manufacture of building products (and.with. No. 1085958, C 04 V 19/06, C 04 V 43/12), including, wt.%:

Smelting heads - 50.0 ... 55.0

Trisulfide piperidine - 1.0 ... 1.1

Flax fire - 8.0 ... 10.0

Ground quartz sand - 35.0 ... 40.0

The disadvantage of this composition is the use of expensive and potentially hazardous to human health organic additives - trisulfidepiperidine. In addition, quartz sand is used as a filler, which, under the action of ionizing radiation, significantly changes its crystalline structure, which leads to a decrease in the physicomechanical parameters of binders, concrete, and mortars prepared on its basis [1]. The reinforcing additive - flax flax - also undergoes degradation under the influence of ionizing radiation, which will lead to premature destruction of the materials prepared on the specified composition.

The closest is a composition for protection against natural radiation background (patent No. 2153714, G 21 F 1/10, C 04 V 28/36), including, wt.%:

Sulfur - 25 ... 30

Finely ground filler

fractions of 0.14 mm - 20 ... 25

Sand fractions 0.14-5.0 mm - 20 ... 25

Crushed stone fractions of 5.0-10.0 mm - the rest

The disadvantage of this composition for protection against natural radiation background is the insufficiently high tensile strength in bending and the use of radiation-friendly and expensive ultrabasic rocks such as serpentinite or quartzite as filler, sand and gravel.

The purpose of the invention is to increase the bending strength of a binder while maintaining high average density.

This goal is achieved in that the binder, including sulfur and a filler, additionally contains a reinforcing additive and a modifying additive, as a filler it contains barite with a specific surface of 250 m ² / kg and an average density of 4350 kg / m ³ , asbestos fiber as a reinforcing additive and as a modifying additive - paraffin with the following components, wt.%:

Sulfur - 45.75 ... 46.43

Barite with a specific surface

250 m ² / kg and medium density

4350 kg / m ³ - 51.96 ... 52.8

Asbestos fiber - 0.23 ... 1.83

Paraffin - 0.46 ... 0.47

To prepare the binder used technical sulfur that meets the requirements of GOST 127-93.

The use of barite as an filler having an average density of 4350 kg / m ³ and a specific surface area of 250 m ² / kg makes it possible to increase both the average density and the strength of the binder.

The introduction of asbestos fiber into the binder can significantly increase the strength and average density of the binder. The introduction of paraffin can improve the rheological properties of the mixture, increase the strength and protective properties of astringent neutron radiation.

A binder is prepared as follows. Dosed quantities of paraffin and asbestos fiber are introduced into the sulfur melted at a temperature of 150 ... 160 ° C, the mixture is mixed until a homogeneous mass is obtained. Then barite heated to a temperature of 150 ... 160 ° C is introduced and the mixture is again thoroughly mixed, kept for 5 ... 10 minutes at a temperature of 150 ... 160 ° C and placed in heated metal molds. After cooling for 30 ... 40 minutes, the molds are stripped.

The compositions of the proposed binder are shown in table 1, and its properties are shown in table 2.

Table 1 Components The content of components, wt.% Composition 1 2 3 Prototype Sulfur 46.49 46.38 45.75 25 ... 30 Barite 52.8 52.68 51.96 - Asbestos fiber 0.23 0.46 1.83 - Paraffin 0.47 0.47 0.46 - Fine-ground filler fraction 0.14 mm - - - 20 ... 25 Sand fraction 0.14-5.0 mm - - - 20 ... 25 Crushed stone fractions of 5.0-10.0 mm - - - rest

table 2 Indicator Composition 1 2 3 prototype Ultimate shear stress, Pa 57.8 65.8 148.1 - The average density, kg / m ³ 2560 2550 2540 2040 ... 2620 Bending Strength, MPa 14.0 13.5 13.1 - The limit of compressive strength, MPa 51.0 50.8 50,5 12.5 ... 50.5 The coefficient of linear attenuation of γ radiation 0.3 MeV 0.319 0.318 0.317 - 0.5 MeV 0.230 0.220 0.210 - 1 MeV 0.160 0.150 0.140 -

As can be seen from table 2, the proposed binder has the rheological properties of injection mixtures, a sufficiently high average density (comparable to the prototype), high values of the coefficient of linear attenuation of γ-radiation and higher compressive and bending strengths.

Literature

1. Dubrovsky VB Radiation resistance of building materials. - M .: Stroyizdat, 1977 .-- 285 p.

Claims (1)

A binder for the manufacture of radiation-protective building materials, including sulfur and a filler, characterized in that it contains barite with a specific surface area of 250 m ² / kg and an average density of 4350 kg / m ³ and an additional modifying additive - paraffin and reinforcing additive - asbestos fiber in the following components, wt.%:  Sulfur 45.75 ... 46.43  The specified barite 51.96 ... 52.8 Paraffin 0.46 ... 0.47 Asbestos fiber 0.23 ... 1.83