FI79693C - FOERFARANDE FOER FRAMSTAELLNING AV ETT VAERMEISOLERANDE MATERIAL. - Google Patents

Description

1 79693

This invention relates to the production of building materials and in particular to a process for the production of a thermal insulation material.

The thermal insulation material produced by the method according to the invention can be widely used in industrial and agricultural construction, in structures as thermal insulation on reinforced concrete and metal decks, as thermal insulation in pipelines, process industry structures and cables.

Thermal insulation materials are known which contain by weight: expanded perlite sand 55-70 low melting petroleum bitumen 6-15 asbestos fibers 10-20 clay 5-14 organic binder.

‘· 1-2 parts by weight of carboxymethyl_cellulose or 2-10 parts by weight of sulphite yeast mash obtained from the manufacture of sulphite cellulose liquor (SU inventor certificates 188880, 589237) are used as the organic binder.

These thermal insulation materials are prepared by mixing bituminous clay paste, asbestos slurry and an organic binder. The prepared casting mixture is fed to a casting unit, where it is formed into moldings (plates, chutes, segments), which are then heat treated.

According to SU inventor's certificate 589237, the heat treatment is carried out in several stages: - most of the water is removed at a temperature of 200-220 ° C for 3-4 hours; dried to completely remove moisture at 120-130 ° C for 10 hours; the dried sheets are heated to melt the bitumen at 140-150 ° C for 3-4 hours, followed by cooling.

2,79693 Such thermal insulation materials are characterized by low water absorption, low thermal conductivity, but due to their bitumen content, these materials can only be used at low temperatures because they are flammable. Due to their loose structure, they shrink unevenly in the moldings, their mechanical strength is inconsistent through the mass of the moldings and the high moisture content in the casting mixture requires long (17-19 hours) heat treatment and the use of various complex manufacturing tools.

Also known is a thermal insulation material and a process for its preparation (SU inventor certificate 785265) from a mixture containing by weight: lignosulfonic acids or their water-soluble salts 55-70 fillers 6-90 phosphoric acid 2-40 water the rest.

As the filler, any expanded material which is inert to the organic binder can be used, such as expanded perlite sand, claydite gravel, basalt wool. As lignosulfonic acid or its water-soluble salt, sulfite yeast mash from pulp and paper mills can be used.

The above organic binder is mixed with orthophosphoric acid until they dissolve in each other at a temperature of 40-95 ° C. The concentration of the resulting mixture is adjusted by evaporation or dilution with water. This mixture is mixed with the filler, then molded into molds and heat treated at 200 ° C for 8 hours.

By carrying out the method under such conditions and using the component ratios described above, it is possible to produce a thermal insulation material having good mechanical properties but a low water resistance coefficient.

The presence of phosphoric acid in the mixture results in the resulting thermal insulation material deteriorating the corrosion resistance of the metal surfaces in contact with it.

It is an object of the present invention to provide such a method for producing a heat insulating material using a suitable organic binder and selecting the heat treatment conditions of the mixture so as to produce a heat insulating material which provides corrosion resistance and good water resistance as well as good water resistance. .

This object is achieved by a process for preparing a thermal insulation material by mixing expanded perlite sand with an aqueous solution of an organic binder in the form of lignosulphonic acid salts into a uniform mixture, forming moldings from the mixture and heat treating them from an organic binder. , having a viscosity of 0.7 to 50 kPa.s, and that the heat treatment is performed at a temperature of 220 to 260 ° C.

The use of the above-mentioned organic binder and the above-mentioned treatment conditions makes it possible to produce a thermal insulation material having good mechanical strength properties, which is also very water-resistant and ensures corrosion resistance of metal surfaces in contact with it.

The thermal insulation material produced by the method according to the invention belongs to the group of non-combustible materials and cannot be used for insulation purposes on surfaces with a temperature of up to 200 ° C.

The method according to the invention enables the extensive use of waste materials obtained from the pulp and paper industry and, compared to known methods, it requires less energy and labor.

In order to improve the water resistance of the thermal insulation material according to the invention while maintaining its performance properties, it is recommended that mixing be performed using the following component ratios by weight: 4,79693 expanded perlite sand 100 aqueous solution of organic binder in the form of lignosulfonic acid salts

In order to improve the bending strength of the thermal insulation material according to the invention, it is further recommended to add asbestos fibers in the mixing step in an amount of 20 to 50 parts by weight per 100 parts of expanded perlite sand.

In the process for preparing the thermal insulation material according to the invention, expanded oerlite sand (SPS) and an aqueous solution of an organic binder in the form of salts of lignosulfonic acids are mixed into a uniform mixture. Wastes from the pulp and paper industry can be used as the aqueous solution of the organic binder, namely: sulphite alcohol broth (SAS) or sulphite yeast mash (SYM), which differ in the content of difficult-to-ferment sugars (pentoses). The aqueous solution of organic binder obtained from pulp and paper mills is characterized by varying amounts of dry matter and varying viscosity. The required viscosity of the aqueous solution of the organic binder is obtained either by evaporation or by dilution with water. In order to ensure good wetting of the SPS surface in order to obtain a uniform mixture and a water-resistant non-combustible thermal insulation material with good mechanical strength properties, it is necessary to use an aqueous solution of an organic binder having a viscosity of 0.7-50 kPa.s. The use of an organic binder with a viscosity of less than 0.7 kPa.s makes it difficult for the different granules of SPS to bond to each other due to the low dry matter content of the binder solution and thus significantly reduces the water resistance and mechanical strength properties of the thermal insulation material.

. Use of an aqueous solution of an organic binder having a viscosity; is more than 50 kPa.s, causes poorer wetting of the SPS surface, makes it difficult to form a uniform mixture, as a result of which the properties of the produced thermal insulation material vary through the mass.

A significant advantage of the method according to the invention is the ability of the manufactured thermal insulation material to retain its physico-mechanical properties despite the influence of various atmospheric factors such as snow, rain and the like, which property is due to its good water resistance.

The water resistance of a thermal insulation material is characterized by a water resistance factor (K ^). This is equal to the ratio of the final compressive strength of the material sample boiled in distilled water and dried at 100 + 5 ° C to the final compressive strength of the original sample.

In order to obtain a water-resistant material with good chemical and mechanical properties, it is recommended to mix the components in the following proportions by weight: SPS - 100, aqueous solution of organic binder in the form of salts of lignosulfonic acids (calculated as dry matter) - 30-105. If the dry matter content of the organic binder drops below 30 parts by weight, unbound SPS granules are formed, which in turn causes the properties of the obtained thermal insulation material to vary throughout the pulp and this also contributes to more complete combustion of the organic binder on the SPS granules. If the dry matter content of the organic binder in the mixture is more than 105 parts by weight, the porosity of the material decreases, its bulk density increases and the thermal conductivity of the products made therefrom increases. In order to improve the mechanical strength properties of the thermal insulation material and its use properties (higher flexural strength, flexibility, lower brittleness, higher durability of the raw materials), asbestos fibers in an amount of 20 to 50 parts by weight can be added to the mixture (in addition to SPS). 100 parts by weight SPS.

If less than 20 parts by weight of asbestos fibers are included in the mixture, the physico-technical properties of the thermal insulation material do not: improve, whereas if more than 50 parts by weight of asbestos fibers are added, the compressive strength of the thermal insulation material deteriorates.

From the homogeneous mixture prepared as described above, other precursors of the desired shape are then formed, either continuously or intermittently. When molding, the compaction coefficient of the mixture is adjusted depending on the required bulk density, strength and thermal conductivity of the thermal insulation material. The compaction factor K, = 2-4. The heat treatment of the prepared precursor is carried out in one step at a temperature of 220-260 ° C. The duration of the heat treatment of the preform is selected based on the quality of the components of the mixture and the temperature used in the heat treatment. At the above temperatures, the duration is 4.5 to 5.8 hours; the water resistance coefficient Kw of the thermal insulation material is then 0.65 to 0.88.

Heat treatment of the precursor at a temperature below 220 ° C does not allow the production of a water-resistant thermal insulation material. Thus, heat treatment of the precursor at 210 ° C for 5.8 hours gives a thermal insulation material having a water resistance coefficient of only K ,, = 0.27 compared to K ,, = 0.65 with a material w 'w' heat treated at 220 ° C.

Raising the heat treatment temperature above 260 ° C and extending the treatment time beyond 4.5 hours do not result in a higher water resistance factor for the thermal insulation material. When heat-treated at 270 ° C for 4.5 hours, the water resistance factor Kw is 0.88, which is not higher than the Kw value of the material heat-treated at 260 ° C for the same length of time. At such temperature and time parameters, polycondensation of the organic binder in the form of lignosulfonic acid salts results in the formation of a water-insoluble polymer due to the removal of OH groups - phenolic and alcohol hydroxyl groups - and the conversion of SO 2 groups in the lignosulfonate molecule. to form alkali metal sulfates.

It has been found that the bond between the resulting water-insoluble polymer and the expanded perlite sand is of the adhesion type.

Thus, the water resistance of the resulting thermal insulation material determines; occurs mainly in heat treatment from the structure of a water-insoluble polymer formed by an organic binder.

3 .....

Such a lamination insulation material with a bulk density of 400 kg / m 3 has a compressive strength of 1.6 MPa, which is 4 times higher than that of expanded perlite sand li 7,79693, while having good water resistance (K = 0.65-0.88). The thermal insulation material prepared by the method according to the invention does not contain compounds which reduce the corrosion resistance of the metals in contact with the material during use. This property is determined by measuring the pH of an aqueous extract obtained by boiling a sample of thermal insulation material for 4 hours in distilled water.

The pH obtained is 7 (neutral medium), while the pH of the aqueous solution of the organic binder in the form of lignosulfonic acid salts is 4.57-4.67 (acidic medium).

Such a thermal insulation material can be used in construction as a thermal insulation of pipelines, process equipment and outposts, as a thermal shield on a cover made of reinforced concrete and form metal.

To illustrate the invention, a few application examples are presented below.

Example 1

The mixer is charged with 225 kg (100 parts by weight) of expanded ·) '* perlite sand with a bulk density of 75 kg / m "and 340 kg of an aqueous solution of V sulphite yeast mash (30 parts by weight in the dry state) with a viscosity of 0.7 kPa .s, and the components are mixed.The resulting mixture is a uniform mass which is fed to a conveyor press and molded to a K Jens value of 2.5.

• * The preform thus prepared is heat-treated in a tunnel kiln at 220 ° C for 5.8 hours. The resulting thermal insulation material has the following properties:

Bulk density, kg / m ^ 250

Final compressive strength, MPa 0.25

Final bending strength, MPa 0.15

Water resistance factor (Kw) 0.65 "Heat conductivity coefficient W / m.K 0.07

The pH of the aqueous extract after boiling the material in distilled water for 4 hours was 6.85

Example 2

225 kg (100 parts by weight) of expanded 3 8 79693 perlite sand with a bulk density of 75 kg / m and 450 kg of an aqueous solution of sulphite yeast musk (105 parts by weight in the dry state) with a viscosity of 50 kPa.s are charged to the mixer and the components mixed. The resulting mixture as a uniform mass is fed to a conveyor press and molded to a Kdens value of 2.5. The preform thus obtained is heat-treated in a tunnel oven at 260 ° C for 4.7 hours. The resulting thermal insulation material has the following properties: 3

Bulk density, kg / m 400

Final compressive strength, MPa 1.0

Final bending strength, MPa 0.5

Water resistance factor (Kw) 0.88 Heat conductivity coefficient W / m.K 0.078

PH of the aqueous extract after boiling the material in distilled water for 4 hours 7.05.

Example 3

375 kg (100 parts by weight) of expanded perlite sand with a bulk density of 75 kg / m and 600 kg of an aqueous solution of sulphite yeast mash (30 parts by weight as dry matter) with a viscosity of 0.7 kPa.s are charged to the desiccator and the components are mixed . The resulting mixture as a uniform mass is fed to a conveyor press and formed into a Kdens value of 4. The preform thus prepared is heat-treated in a tunnel oven at 260 ° C for 5.2 hours. The resulting thermal insulation material has the following properties:

Bulk density, kg / m 410

Final compressive strength, MPa 1.5

Final bending strength, MPa 0.6

Water resistance factor (Kw) 0.88 Heat conductivity coefficient W / m.K 0.09

PH of the aqueous extract after boiling the material in distilled water for 4 hours 7.0.

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Example 4

200 kg (100 parts by weight) of expanded perlite sand with a bulk density of 100 kg / m 2 and 410 kg of an aqueous solution of sulphite yeast mash (105 parts by weight as dry matter) with a viscosity of 50 kPa.s are charged to the mixer and the components are mixed. The unit mass mixture is fed to a conveyor press and formed to a Kdens value of 2.0. The preform thus prepared is heat-treated in a tunnel oven at 260 ° C for 5.3 hours. The resulting thermal insulation material has the following properties:

Bulk density, kg / min + ^ 370

Final compressive strength, MPa 1.4

Final bending strength, MPa 0.5

Water resistance factor (Kw) 0.88 Heat conductivity coefficient W / m.K 0.075

PH of the aqueous extract after boiling the material in distilled water for 4 hours 7.05.

Example 5

375 kg (100 parts by weight) of expanded 3 perlite sand with a bulk density of 75 kg / m 2 and 410 kg of an aqueous solution of sulphite alcohol broth (55 parts by weight as dry matter) with a viscosity of 50 kPa.s are charged to the mixer and the components are mixed. The mixture as a uniform mass is fed to a conveyor press and molded to a K <3ens value of 4. The preform thus prepared is heat-treated in a tunnel oven at 220 ° C for 4.8 hours. The resulting thermal insulation material has the following properties:

Bulk density, kg / m 500

Final compressive strength, MPa 1.9

Final bending strength, MPa 0.75

Water resistance factor (Kw) 0.68 Heat conductivity coefficient W / m.K 0.095

PH of the aqueous extract after boiling in distilled water for 4 hours 6.9.

10 79693

Example 6

360 kg (100 parts by weight) of expanded 3 perlite sand with a bulk density of 100 kg / m 2 and 385 kg of an aqueous solution of sulphite alcohol broth (55 parts by weight as dry matter) with a viscosity of 50 kPa.s are charged to the mixer and the components are mixed. The mixture in the form of a uniform mass is fed to a conveyor press and molded into an initial value. The preform thus prepared is heat-treated in a tunnel oven at 260 ° C for 4.5 hours. The resulting thermal insulation material has the following properties:

Bulk density, kg / cm -1 470

Final compressive strength, MPa 1.8

Final bending strength, MPa 0.7

Water resistance factor (Kw) 0.88 Heat conductivity coefficient W / m.K 0.092

PH of the aqueous extract after boiling the material in distilled water for 4 hours 7.0.

Example 7

200 kg (100 parts by weight) of expanded 3 perlite sand with a bulk density of 100 kg / m 2, 40 kg of fibrous asbestos (20 parts by weight) and 300 kg of an aqueous solution of sulphite yeast mash (50 parts by weight in dry matter) are charged to the mixer, having a viscosity of 16 kPa.s, and the components are mixed. The mixture as a homogeneous mass is fed to a conveyor press and molded to a K. value 2. The preform thus prepared is treated in a tunnel kiln at 240 ° C for 5.2 hours. The resulting thermal insulation material has the following properties:

Bulk density, kg / m ^ 300

Final compressive strength, MPa 0.55

Final bending strength, MPa 0.5

Water resistance factor (Kw) 0.75 Heat conduction coefficient W / m.K 0.075

PH of the aqueous extract after boiling in distilled water for 4 hours 7.

Il il 79693

Example 8

The mixer is charged with 200 kg (100 parts by weight) of expanded perlite sand with a bulk density of 100 kg / m3, 100 kg of fibrous asbestos (50 parts by weight) and 300 kg of an aqueous solution of sulphite yeast mash (50 parts by weight in dry matter), which the viscosity is 16 kPa.s, and the components are mixed. The mixture as a uniform mass is fed to a conveyor press and molded to a Kdens value of 2. The preform thus prepared is heat-treated in a tunnel oven at 240 ° C for 5.2 hours. The resulting thermal insulation material has the following properties:

Bulk density, kg / m 360

Final compressive strength, MPa 0.7

Final bending strength, MPa 0.6

Water resistance factor (Kw) 0.76 Heat conductivity coefficient W / m.K 0.079

PH of the aqueous extract after boiling in distilled water for 4 hours 7.

Example 9

200 kg (100 parts by weight) of expanded perlite sand with a bulk density of 100 kg / m and 320 kg of an aqueous solution of sulphite yeast mash (30 parts by weight, calculated as dry matter) with a viscosity of 0.7 kPa.s are charged to the mixer and the components are mixed . The mixture as a uniform mass is fed to a conveyor press and formed into κ ^ θη5-3Γνοοη 2.0. The preform thus prepared is heat-treated in a tunnel oven at 220 ° C for 5.7 hours. The resulting thermal insulation material has the following properties:

Bulk density, kg / m 240

Final compressive strength, MPa 0.25

Final bending strength, MPa 0.15

Water resistance factor (Kw) 0.65 Heat conductivity coefficient W / m.K 0.07

PH of the aqueous extract after boiling in distilled water for 4 hours 6.9.

Example 10

The mixer is charged with 350 kg (100 parts by weight) of expanded 3 12 79693 perlite sand having a bulk density of 100 kg / m 2 and 550 kg of an aqueous solution of sulphite yeast musk (30 parts by weight as dry matter) with a viscosity of 0.7 kPa.s, and the components are mixed. The uniform mass mixture is fed to a conveyor press and formed to a K i value of 3.0. The preform thus prepared is heat-treated in a tunnel oven at 260 ° C for 5.1 hours. The resulting thermal insulation material has the following properties: 3

Bulk density, kg / m 400

Final compressive strength, MPa 1.5

Final bending strength, MPa 0.6

Water resistance factor (Kw) 0.88 Heat conductivity coefficient W / m.K 0.09

PH of the aqueous extract after boiling the material in distilled water for 4 hours 7.0.

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Claims (3)

13 7969 3 1. A mixture for the production of a color-insulating material, which can be used for the treatment of organic compounds in the form of a salt of a sulphonylurium, to form a homogeneous mixture, to form a mixture and to form a mixture, organic binders in the form of a lignosulfonic acid salt with a viscosity of 0.7-50 kPa.s, och ^ att Värmebehandlingen genomförs at a temperature of 220-260 C. A process for preparing a heather dietary material, which process comprises mixing expanded peritite sand and an aqueous solution of an organic binder in the form of lignosulfonic acid salts into a uniform mixture, followed by molding and heat treatment, characterized in using an aqueous solution of an organic binder in the form of lignosulfonic acid salts. s, o and that the heat treatment is performed at a temperature of 220-250 ° C. 2. A patent according to claim 1, which comprises a component according to the invention, in the form of: 14 79693 means perlite and 100 wattages of an organic binder in the form of 1-toner, preferably 30-105. Process according to Claim 1, characterized in that the mixing is carried out using the following proportions of components by weight: expanded peritite sand 100 in aqueous solution of organic binder in the form of lignosulfonic acid salts, in dry matter 30 to 105. A method according to claim 1 or 2, characterized in that asbestos fibers are further added to the mixture during mixing in an amount of 20 to 50 parts by weight per 100 parts by weight of expanded perlite sand. 3. A patent according to claim 1 or 2, which comprises a mixture according to the invention of a fibrillator and a game of 20 to 50 wafers per 100 wafers per unit. li