WO2012034404A1 - Gypsum whisker, enhanced mineral wool sound-absorbing plate containing the same and preparation method thereof - Google Patents

Abstract

A gypsum whisker, an enhanced mineral wool sound-absorbing plate containing the same and preparation method thereof are disclosed. The gypsum whisker is prepared with desulphurized gypsum having a purity of 75-90% by steps of slurrying, removing impurities, hydrothermally synthesizing and drying. The enhanced mineral wool sound-absorbing plate contains, by weight, 100 parts of mineral wool, 10-16 parts of attapulgite clay, 5-9 parts of modified starch, 0.6-1.0 parts of polyacrylamide, 0.5-0.7 parts of emulsified paraffin wax, 0.4-0.7 parts of aluminum sulfate and 2-30 parts of the gypsum whisker. The method for preparing the plate includes steps of proportioning, molding, drying and surface-finishing. The gypsum whisker has advantages of high strength, good toughness, high temperature resistance and chemical corrosion resistance, etc. By adding the gypsum whisker, the strength of the plate is enhanced and the bending failure load is increased by 10-30%. In addition, the invention makes effective use of industrial waste and decreases production cost.

Description

 Gypsum whisker, reinforced mineral wool sound absorbing plate containing the gypsum whisker and preparation method thereof

Technical field

 The invention relates to a building decoration material and a preparation method thereof, in particular to a gypsum whisker, a reinforced mineral wool sound absorbing plate containing the gypsum whisker and a preparation method thereof.

Background technique

 Mineral wool board is a new type of building material. It has excellent fireproof, waterproof, moisture proof, soundproofing, heat insulation and easy deep processing. It is widely used in decorative ceilings of public buildings at home and abroad, and can also be used in industry. Factory buildings, high-end residences and high-rise buildings.

 Mineral wool boards generally contain a variety of fillers to enhance physical properties. Gypsum whiskers are non-toxic and harmless. They have the advantages of high strength, good toughness, high temperature resistance, chemical resistance and easy surface treatment. Therefore, they can be used as medium-strength fillers.

Gypsum whiskers can be made from desulfurized gypsum. Desulfurization gypsum is an industrial by-product gypsum obtained by desulfurizing and purifying flue gas generated after combustion of a sulfur-containing fuel (coal, oil, etc.), and is obtained by reacting S0 _{2 in} flue gas with limestone CaC0 ₃ . Its main component is CaS0 ₄ .23⁄40, and a small amount of CaC0 ₃ and CaS0 ₃ as well as some impurities such as fly ash, organic carbon, calcium carbonate, aluminum oxide, silicon oxide and iron oxide. The purity of the desulfurized gypsum varies greatly depending on the desulfurization process and the purity of the limestone feedstock. The purity of the desulfurized gypsum is a key factor affecting the synthesis of gypsum whiskers. If the gypsum contains more impurities, it will cause the whiskers to grow without orientation. Therefore, the preparation of gypsum whiskers is usually in the form of gypsum having a very high level of gypsum, such as the method of CN 200810011193.5 (the method of "preparation of calcium sulfate whiskers using flue gas desulfurization gypsum"). The content of calcium sulphate is higher than 90%. However, the desulfurization process in China is relatively backward, and the purity of desulfurization gypsum is generally between 75% and 90%. Therefore, the existing gypsum whisker preparation process is not applicable to the purity of the current desulfurization gypsum in China.

Therefore, it is necessary to provide a gypsum whisker prepared by a new process, and a reinforced mineral wool sound absorbing plate containing the gypsum whisker and a preparation method thereof. Summary of the invention

 A first object of the present invention is to provide a gypsum whisker which can be prepared using desilsil gypsum having a purity of between 75% and 90%.

 A second object of the present invention is to provide a reinforced cotton wool sound absorbing plate which is added to the reinforced cotton wool sound absorbing panel to improve the strength of the mineral wool sound absorbing panel.

 A third object of the present invention is to provide a method of preparing the above-described reinforced mineral wool sound absorbing panel.

 The present invention relates to a gypsum whisker which is obtained by the following steps:

 Step 1: Mixing the desulfurized gypsum with a purity of 75% to 90% with water to form a slurry having a solid content of 2% to 15%;

 Step 2: adding dilute acid to the slurry prepared in step 1, filtering and washing, and then adding dilute acid to adjust the pH of the slurry to 1 to 5, the solid content is 2% to 15%, and then the The slurry is placed in an autoclave, and oxygen is introduced at a temperature of 50 to 90 ° C and a stirring speed of 50 rpm to 300 rpm, and the reaction is stopped after 5 to 30 minutes;

 Step 3: After adding a crystal stabilizer to the autoclave, the autoclave is sealed, and the temperature is maintained at a temperature of 110 160 ° C and a stirring speed of 50 rpm to 300 rpm. 600 minutes for the hydrothermal synthesis reaction, and then the reaction product is filtered and washed;

 Step 4: The washed product is dried at 110 to 600 ° C for 2 to 5 hours to obtain the gypsum whisker.

 Preferably, the prepared gypsum whiskers have a diameter of 0.1 to 4 μm and an aspect ratio of 30 to 150.

 Wherein, the pH value of the slurry in step 2 is preferably 2 to 3, and the gemstone whiskers prepared in the range have a relatively large aspect ratio and a better performance. The crystal stabilizer of step 3 is selected from the group consisting of magnesium chloride, sodium tripolyphosphate, ethylenediaminetetraacetic acid (EDTA), sodium chloride, aluminum silicate, sodium oleate, sodium stearate, and dodecylbenzene. Sodium, oxalic acid, urea, sodium laurate, sodium citrate, and combinations thereof, the crystal form stabilizer is present in an amount of from 0.01% to 2% by weight.

 The invention also relates to an enhanced mineral wool sound absorbing panel comprising the following components in a weight ratio: mineral wool: 100 parts

Attapulgite clay: 10~16 parts Modified starch:

 Polyacrylamide: 0.6-1.0

石克酸铝: 0.4-0.7份 Emulsified paraffin:

Aluminium silicate: 0.4-0.7 parts

 The above gypsum whiskers: 2~30 parts.

 Preferably, the mineral wool is granular cotton made from industrial waste residue, blast furnace slag. The invention also relates to a method for preparing a reinforced cotton sound absorbing panel, comprising the following steps: Step 1: weighing 100 parts by weight of mineral wool, 10-16 parts by weight of attapulgite clay, 5-9 parts by weight Starch starch, 0.6 to 1.0 part by weight of polyacrylamide, 0.5 to 0.7 part by weight of emulsified paraffin, 0.4 0.7 part by weight of aluminum sulfate, and 2 to 30 parts by weight of the above-mentioned gypsum whisker, and the above raw materials are stirred and mixed. Mixture;

 Step 2: The mixture is formed by a wet process, and cut into a plate by a cutter; Step 3: The plate is dried, the drying temperature is 230-285 ° C, and the drying time is 2 hours. Step 4: cutting the dried plate according to specifications, and performing surface finishing to obtain the enhanced mineral wool sound absorbing plate.

 Preferably, the mineral wool is granular cotton made from industrial waste residue, blast furnace slag. Wherein the wet drawing process in the step 2 is carried out in a web forming machine, and after forming, it is preferably cut into a plate by high pressure water in a cutting machine; the drying temperature in the step 3 is preferably 260 ° C; The surface finishing method of the board in 4 is the same as the existing surface finishing method of the mineral wool board.

 The preparation method of the reinforced cotton wool sound absorbing panel of the invention further comprises the step of packaging, that is, the finished product is qualified and packaged into the warehouse.

 The invention has the following advantages:

In the present invention, gypsum whiskers are prepared from the desulfurized gypsum having a lower purity, and the strength of the mineral wool sound absorbing plate is enhanced by adding gypsum whiskers. The gypsum whisker prepared by the invention has the advantages of high strength, good toughness, high temperature resistance, chemical resistance, etc. It is a fine single crystal, the internal structure is very complete, and the highly ordered atomic arrangement makes it almost free of any common materials. Defects such as holes, impurities, and particle interfaces, the intensity is close to the theoretical value of the crystal - the intensity of the inter-atomic bond. Therefore, the mineral wool of the present invention is sucked After the soundboard is added to the prepared gypsum whiskers, the bending failure load is increased by 10 to 30%. In addition, the present invention can fully utilize the desulfurization gypsum with a purity of 75% to 90%, and not only fully utilizes the industrially desulfurized gypsum to realize waste recycling, but also greatly reduces the production cost. BRIEF abstract

 The embodiments of the present invention are further described below in conjunction with the accompanying drawings:

 Figure 1 is a flow chart of a method for preparing gypsum whiskers of the present invention;

 2 is a flow chart of a method for preparing a reinforced cotton wool sound absorbing panel of the present invention. Preferred embodiment of the invention

 Preparation of gypsum whiskers:

 Gypsum whisker preparation was carried out in accordance with the flow chart shown in Fig. 1, and each of the materials in the following examples was commercially available.

 Example 1

 Step 1: Mix 75% of the desulfurized gypsum with water to make a slurry with a solid content of 15%.

 Step 2: Add dilute sulfuric acid to the slurry prepared in step 1, filter and wash, then add dilute sulfuric acid to adjust the pH of the slurry to 1 and the solid content to 15%, and then put the slurry into the autoclave. Oxygen was introduced at a temperature of 90 ° C and a stirring speed of 300 rpm, and the reaction was stopped after 30 minutes of reaction.

 Step 3: After adding a crystal stabilizer (1.5% by weight of EDTA and 0.5% by weight of sodium sulphate) to the autoclave, close the inlet and outlet to make the high pressure The reaction vessel was sealed. Then, the mixture was kept at a temperature of 160 ° C and a stirring speed of 50 rpm for 600 minutes to carry out a hydrothermal synthesis reaction, and then the reaction product was filtered and washed.

 Step 4: The washed product was dried at 110 ° C for 5 hours to obtain a gypsum whisker product σ.

Example 2 Step 1: The desulfurized gypsum with a purity of 90% was uniformly mixed with water to prepare a slurry having a solid content of 2%.

 Step 2: Add dilute sulfuric acid to the slurry prepared in step 1, filter and wash, then add dilute sulfuric acid to adjust the pH of the slurry to 5, the solid content is 2%, and then put the slurry into the high pressure reaction kettle. Oxygen was introduced at a temperature of 50 ° C and a stirring speed of 50 rpm, and oxygen was stopped after 5 minutes of reaction.

 Step 3: After adding a crystal stabilizer (0.01% by weight of magnesium chloride) to the autoclave, close the inlet and outlet to seal the high pressure reactor. Then, the mixture was kept at a temperature of 110 ° C and a stirring speed of 300 rpm for 240 minutes to carry out a hydrothermal synthesis reaction, and then the reaction product was filtered and washed.

 Step 4: The washed product was dried at 300 ° C for 3 hours to obtain a gypsum whisker product σ.

 Example 3

 Step 1: Mix 85% of the desulfurized gypsum with water to make a slurry with a solid content of 8%.

 Step 2: Add dilute sulfuric acid to the slurry prepared in step 1, filter and wash, then add dilute sulfuric acid to adjust the pH of the slurry to 4, the solid content is 8%, and then put the slurry into the high pressure reaction kettle. Oxygen was introduced at a temperature of 75 ° C and a stirring speed of 200 rpm, and the reaction was stopped after 15 minutes.

 Step 3: After adding a crystal stabilizer (0.3% by weight of sodium chloride) to the autoclave, close the inlet and outlet to seal the high pressure reactor. Then, the mixture was kept at a temperature of 130 ° C and a stirring speed of 150 rpm for 30 minutes to carry out a hydrothermal synthesis reaction, and then the reaction product was filtered and washed.

 Step 4: The washed product was dried at 600 ° C for 2 hours to obtain a gypsum whisker product.

The gypsum whiskers prepared in the above examples have a diameter of 0.1 to 4 μm and a length to diameter ratio of 30 to 150. Enhance the preparation of mineral wool sound absorbing panels:

 The preparation of the reinforced cotton wool sound absorbing panel was carried out in accordance with the flow chart shown in Fig. 2, and each of the materials in the following examples was commercially available. Example 1

 Step 1: Weigh 100 parts by weight of mineral wool, 10 parts by weight of attapulgite clay, 5 parts by weight of modified starch, 0.6 parts by weight of polyacrylamide, 0.5 parts by weight of emulsified paraffin, 0.4 parts by weight of aluminum sulfate, And gypsum whiskers prepared in Example 1 in the preparation of the above gypsum whiskers in an amount of 12 parts by weight. The above raw materials are mixed with water, and thoroughly mixed in a batching mixer to prepare a mixture, and the mixture is output to a returning machine.

 Step 2: The above mixture is formed in a web forming machine by a wet process, and cut into sheets by high pressure water.

 Step 3: The plate is conveyed to a drying kiln through a distributor and dried at a temperature of about 260 ° C for about 2 hours.

 Step 4: Cut the dried plate into 600cm X 600cm size and finish the surface. The surface is processed in the same way as the existing mineral wool board surface.

 Step 5: The finished board is made into a 12mm thick reinforced cotton wool sound absorbing board, and the finished product is inspected and packaged.

 Example 2

 In this embodiment, each component is weighed according to the following ratio: 100 parts by weight of mineral wool, 14 parts by weight of attapulgite clay, 8 parts by weight of modified starch, 0.9 parts by weight of polyacrylamide, 0.6 weight. Parts of emulsifying paraffin, 0.6 parts by weight of aluminum sulfate, and 30 parts by weight of gypsum whiskers prepared in Example 1 in the preparation of the above gypsum whiskers. The preparation procedure was the same as in Example 1, and a 12 mm thick reinforced cotton wool sound absorbing panel was obtained.

 Example 3

In this embodiment, each component is weighed according to the following ratio: 100 parts by weight of mineral wool, 16 parts by weight of attapulgite clay, 9 parts by weight of modified starch, 1.0 part by weight of polyacrylamide, 0.7 weight Parts of emulsifying paraffin, 0.7 parts by weight of aluminum sulfate, and 2 parts by weight of gypsum whiskers prepared in Example 1 in the preparation of the above gypsum whiskers. The preparation procedure was the same as in Example 1, and a 12 mm thick increase was obtained. Strong mineral wool sound absorption board finished.

 The reinforced cotton wool sound absorbing panels prepared in the above Examples 1 to 3 were respectively subjected to physical property tests, and the test results are shown in Table 1 below.

 Table 1 Performance Evaluation of Enhanced Mineral Wool Acoustic Panel

 As shown in Table 1, the reinforced cotton wool sound absorbing plate prepared by the invention has light weight, good sound insulation effect, and the physical and mechanical properties of the reinforced cotton sound absorbing plate are significantly improved compared with the traditional mineral wool sound absorbing plate. The bending damage load of the reinforced cotton wool sound absorbing plate prepared in Example 1 is increased by about 30%, and the bending damage load of the reinforced cotton wool sound absorbing plate obtained in Embodiment 2 is increased by about 18%, and the embodiment 3 is The bending damage load of the enhanced mineral wool sound absorbing panel is increased by about 10%.

Industrial Applicability The gypsum whiskers prepared by the invention have the advantages of high strength, good toughness, high temperature resistance and chemical corrosion resistance, and can be added as fillers to the mineral wool sound absorbing panels to improve the strength of the mineral wool sound absorbing panels.

 Compared with the traditional mineral wool sound absorbing panels, the reinforced cotton wool sound absorbing panels prepared by the invention have significantly improved physical and mechanical properties, especially bending damage loads, and are therefore more suitable for decorative ceilings of public buildings, industrial plants, high-grade residences and high-rise buildings. The building's decorative building materials.

 The invention fully utilizes industrial waste and greatly reduces production costs.

Claims

Claim  1. A gypsum whisker prepared by the following steps:  Step 1: Mixing the desulfurized gypsum with a purity of 75% to 90% with water to form a slurry having a solid content of 2% to 15%;  Step 2: adding the dilute acid to the slurry prepared in step 1, filtering and washing, and then adding dilute acid to adjust the pH of the slurry to 1 to 5, the solid content is 2% to 15%, and then The slurry is placed in an autoclave, oxygen is introduced at a temperature of 50-90 ° C and a stirring speed of 50 rpm to 300 rpm, and the reaction is stopped after 5-30 minutes. ;  Step 3: After adding a crystal stabilizer to the autoclave, the autoclave is sealed, and the temperature is maintained at a temperature of 110 160 ° C and a stirring speed of 50 rpm to 300 rpm. 600 minutes for the hydrothermal synthesis reaction, and then the reaction product is filtered and washed;  Step 4: The washed product is dried at 110 to 600 ° C for 2 to 5 hours to obtain the gypsum whisker.  The gypsum whisker according to claim 1, wherein the gypsum whiskers have a diameter of 0.1 to 4 μm and an aspect ratio of 30 to 150.  3. The gypsum whisker according to claim 1, wherein the slurry of step 2 has a pH of 2 to 3.  4. The gypsum whisker according to claim 1, wherein the crystal stabilizer of step 3 is selected from the group consisting of magnesium chloride, sodium tripolysilicate, ethylenediaminetetraacetic acid, sodium chloride, aluminum sulfate, sodium oleate, Sodium stearate, sodium dodecylbenzene sulfonate, oxalic acid, urea, sodium laurate, sodium citrate, and combinations thereof.  The gypsum whisker according to claim 1, wherein the crystal stabilizer of the step 3 has a weight percentage of 0.01% to 2%.  6. An enhanced mineral wool sound absorbing panel comprising the following components in a weight ratio:  Mineral wool: 100 parts  Attapulgite clay: 10~16 parts  Modified starch: 5-9 parts  Polyacrylamide: 0.6~1.0 parts Emulsified paraffin: 0.5~0.7 parts Aluminium silicate: 0.4 0.7 parts  The gypsum whisker according to any one of claims 1 to 5, which is 2 to 30 parts.  The reinforced cotton wool sound absorbing panel according to claim 6, wherein the mineral wool is granulated cotton made of blast furnace slag.  8. A method for preparing a mineral wool sound absorbing panel, comprising the steps of:  Step 1: Weigh 100 parts by weight of mineral wool, 10 to 16 parts by weight of attapulgite clay, 5 to 9 parts by weight of modified starch, 0.6 to 1.0 part by weight of polyacrylamide, and 0.5 to 0.7 parts by weight of emulsified paraffin And 0.4-0.7 parts by weight of aluminum sulfate, and 2 to 30 parts by weight of the gypsum whisker according to any one of claims 1 to 5, wherein the raw materials are stirred and mixed to form a mixture;  Step 2: The mixture is formed by a wet process, and cut into a plate by a cutter; Step 3: The plate is dried, the drying temperature is 230-285 ° C, and the drying time is 2 hours. Step 4: cutting the dried plate according to specifications, and performing surface finishing to obtain the enhanced mineral wool sound absorbing plate.  The method for preparing a reinforced cotton wool sound absorbing panel according to claim 8, wherein the mineral wool is granulated cotton made of blast furnace slag.  10. The method of preparing a reinforced cotton wool sound absorbing panel according to claim 8, wherein the drying temperature in the step 3 is 260 °C.