WO2004099102A2

WO2004099102A2 - Composition for blocks for masonry and facing and method for their production

Info

Publication number: WO2004099102A2
Application number: PCT/EP2004/004887
Authority: WO
Inventors: Neofit Assenov Spasov
Original assignee: Simem S.R.L.
Priority date: 2003-05-09
Filing date: 2004-05-07
Publication date: 2004-11-18
Also published as: WO2004099102A3; BG65746B1; BG107787A

Abstract

The invented composition allows the production of four types of blocks for masonry and facing, based on Sorel cement and natural fillings. These blocks have different densities, strength and thermal conductivity, are ecological and can be used in houses, social and agricultural buildings. The method for their production is without thermal treatment and the obtained blocks are uniform with precise dimensions and free of internal stress. The ready blocks can be easily proceeded mechanically and they can be applied without special equipment for masonry and facings.

Description

DESCRI PTION

COMPOSITION FOR BLOCKS FOR MASONRY AND FACING AN D METHOD FOR TH EI R PRODUCTION . TECHNI CAL FI ELD The invention concerns the composition for blocks for masonry and facing, based on Sorel cement and natural fillings , and method for their production. The blocks can be applied as ecolog ical prod uct with low cost and high mechanical characteristics in building and facing houses, social and agricu ltural build ings. BACKGROUND ART

Known are verious types of building blocks (bricks) for masonry and facing: regular (red) bricks - made by forming , drying and baking of clay; Lime bricks - made from milled lime and sand by autoclave treatment; Light and foam building bricks - made from diatomite, swelled volcanic glass or clay mixed with combusting agents (wood shavings, coal dust, etc,); Building blocks from mineralized organic waste and binder - Portland cement; build ing blocks form gas and foam concrete. The disadvantages of the known blocks for masonry and facing is the big energy consumption (for drying, baking, thermal and autoclave treatment) and also the liberation of harm emissions of CO₂, dust and others in the environment.

It is well-known that magnesium oxide (the so called caustic magnesite) at the presence of water solution of MgCI₂, MgSO₄ and other salts, easily combines with d ifferent organic and inorganic added fillings and inorganic pigments is used for the production of artificial building materials - xilolite and fibrolite. Their composition includes - caustic magnesite, wood shavings and water solution of

MgCI₂. These materials are used for seamless floor covering and

tiles. The disadvantages of the ready products from xilolite and

fibrolite are deformations (distortion, warping), spider-web surface cracks and big inner cracks and laminations. These defects are due

to the internal stress in the products.

The method of the production of xilolite tiles includes mixing magnesium oxide with wood shavings and adding water solution of MgCI₂. The tiles are pressed. After that is the thermal treatment of the pressed products in a camera at temperature 40-50°C and cooling to 15-18°C. The ready tiles are washed in warm, circulating water for 12 hours and after that they are dried in drier at temperature 60-70°C for 24 hours. It is necessary the ready tiles to be stored for 3 monts in transitional store house in order to reject the tiles with defects.

The disadvantages of the known method is the thermal and water

processing of the tiles because it prolongs the technological process and raise the cost of the products. DISCLOSURE OF INVENTION

The purpose of the invention is to obtain composition , based on Sorel cement and natural fillings, for the production of blocks for masonry and facing with low density, high strength, low thermal conductivity and free of internal stress.

The raw materials and ready products must be ecological. The productions must be done with minimum energy and without harmful emissions in the environment.

The aim of the invention is solved by the following composition:

1 . Magnesium oxide-caustic magnesite. Finely frind , in quantity

from 25 to 60%.

2. Water solution of MgCI₂ with concentration 18-32°Be, in

quantity from 70 to 100% of the quantity of the magnesium

oxide.

3. Fillings: fine quartz, gypsum, calcium carbonate, barium sulfate, natural clay, swelled volcanic glass, expanded clay,

ashes from Termo-Electric Power Stations; cellulose fibers, wood shavings , wood flour , milled wood barks, fibers form palm trees, rice husk, sunflower husk, cotton seed, waste from flex and hemp proceeding, frail, cut strew and other wastes from cereals in quantity from 40 to 75%, used separately or in combination.

4. Additives: MgSO₄ as a additive to the water solution of MgCI₂ - up to 5% of the MgCI₂ quantity; gypsum up to 10% of the quantity of MgO;

5. Coloring agents - natural and artificial inorganic pigments in

quantity from 0 to 5% of the quantity of dry mixture. BEST MODE FOR CARRYI NG OUT THE INVENTION The essence of the invention is the method of production of the a.m . products including the following technological operations: 1 . Making water solution of MgCI₂ and MgSO₄ with specific concentration - liquid phase; 2. Dosing and mixing the dry powder components in orbital mixer - dry phase;

3. Mixing the dry and liquid phases and receiving forming mass;

4. Forming the blocks by rammer or pressing. Hardening of the

blocks without additional treatment.

5. Releasing the blocks from the forms and qualifying.

The production can be done by hand or by machines with different range of automatization. The optimum temperature for the production process is 15-25°C.

The products are formed as hollow blocks (bricks) with cylindrical

or parallelepiped cavities in iron forms with mobile bottoms. The form can be clamped during the process of hardening. The internal stress arisen in the blocks, which is actually accumulated

energy, have the opportunity to designate by changing the volume of the inner cavities of the blocks. The blocks made from fillings that do not swell when moisten can be formed as a solid bricks.

The main advantage fo the proposed composition and method for

producing blocks for masonry and facing is the very low energy

consumption. The structure of the new material is obtained as a result of chemical and phase transformations due to the internal energy of the system.

The used raw materials are natural, ecological, easy to find and cheap. The production of these blocks does not pollute the environment.

By varying the type and the quantity of the fillings and binder, in the above mentioned limits, four groups of grade of blocks can be

obtained:

Group I : density 400 kg/m³; strength 3 MPa; thermal conductivity

0, 14 W/m°C

Group I I: density 600 kg/m³; strength 6,5 MPa; thermal

conductivity 0, 16 W/m°C

Group I I I: density 850 kg/m³; strength 8 MPa; thermal

conductivity 0, 17 W/m°C

Group IV: density 1000kg/m³; strength 10 MPa; thermal conductivity 0, 19 W/m°C

The quantity of the used coat or glue is very small because of the high flatness of the blocks. The blocks can be easily proceeded.

They can be cut and forged.

Examples of the invention The invention can be illustrated by the following examples:

1 . Block with straw filling

Composition:

- powdered MgO - 42% - cut straw - 58%

- water solution of MgCI₂ - 90% of the MgO

Characteristics:

- density - 400 kg/m³

- strength - 3 MPa

- thermal conductivity - 0, 14 W/m°C 2. Block with perlite filling

Composition: - powdered MgO - 34% -perlite - 66%

- water solution of MgCI₂ - 100% of the MgO

Characteristics:

- density - 540 kg/m³

- strength - 6,5 MPa

- thermal conductivity - 0, 16 W/m°C

3. Block with cotton seed filling

Composition: - powdered MgO - 45%

- cotton seeds - 55%

- water solution of MgCI₂ - 75,6% of the MgO Characteristics:

- density - 1000 kg/m³

- strength - 10 MPa

- thermal conductivity - 0, 18 W/m°C

Claims

1 . Composition for the production of blocks for masonry and

facing with the following characteristics:

Dry phase (mix):

- Magnesium oxide (caustic magnesite) in quantity from 25 to

60%;

- Fillings: fine quartz, gypsum, calcium carbonate, barium

sulfate, natural clay, swelled volcanic glass, expanded clay, ashes from Thermo-Electric Power Stations; cellulose fibers, wood shavings, wood flour, milled wood barks, fibers form palm trees, rice husk, sunflower husk, cotton seed, waste from flex and hemp proceeding, frail, cut strew and other wastes from

cereals in quantity from 40 to 75%, used separately or in combination. - Coloring agents - natural and artificial inorganic pigments in quantity from 0 to 5%.

Liquid phase:

- Water solution of MgCI₂ with concentration 18-32° Be, quantity from 70 to 100% of the MgO quantity. Additives:

-MgSO₄ as a additive to the water solution of MgCI₂ - up to 5% of the MgCI₂ quantity;

- gypsum up to 10% of the quantity of MgO;

2. Method for the production of blocks for masonry and facing including in sequence the preparation of dry and liquid phases, their mixing, homogenization and forming by rammer or pressing and is characterized with the fact that the obtained plastic paste is not trated thermally and is formed as solid or hollow blocks with cylindrical or parallelepiped cavities in iron or plastic forms.