Ceramsite prepared from sludge and preparation method thereof

Abstract

The invention relates to the field of ceramsite materials, in particular to ceramsite prepared from sludge and a preparation method thereof.The ceramsite is prepared from, by weight, 40-60 parts of sludge powder, 10-15 parts of siliceous shale, 10-20 parts of fly ash, 0.5-1 part of CONSOLID444 (C444) and 0.5-1.5 parts of triisopropanolamine, and the sludge is sludge powder with the water content being about 10%. According to the invention, the introduction of CONSOLID444 (C444) can significantly reduce the water absorption rate of the ceramsite, and at the same time, CONSOLID444 cooperates with triisopropanolamine to enrich and improve the internal pore structure of the ceramsite and significantly improve the mechanical properties of the ceramsite. The obtained ceramsite has a rich pore structure, the stacking density is larger than 850 kg / cm < 3 >, the cylinder compressive strength is larger than 8.0 MPa, the 1h water absorption rate is lower than 5%, and the performance requirements of building materials are met.

Description

Technical Field

[0001] The invention relates to the field of ceramsite materials, and in particular to ceramsite prepared by utilizing sludge and a preparation method thereof. Background Art

[0002] As the name implies, ceramsite is a kind of lightweight and porous building material. Due to its superior physical properties, such as fireproofing, sound insulation, heat insulation, crack resistance, etc., it is widely used in the fields of construction, gardening, environmental protection, etc. At present, the ceramsite used in my country is mainly made of clay as the main raw material. Clay mainly comes from the surface soil. If a large amount of ceramsite made of clay is used as a building material, it will destroy a lot of arable land, which is not conducive to sustainable development.

[0003] At present, some foreign research reports have reported that solid wastes such as riverbed mud, fly ash, coal gangue, municipal sludge and red mud are used as materials for the preparation of expanded clay. If solid wastes can be comprehensively utilized and clay and mineral resources can be used less or not at all, it will bring practical economic and social benefits to the research and development of expanded clay.

[0004] Sludge mainly comes from domestic sewage treatment plants and industrial sewage treatment plants. It is composed of about 80% water and about 20% solids, and about 50% of the solids are organic matter. It has internal fuel and foaming agent functions when preparing high-temperature sintered products, and has high recycling value. However, when using sludge to prepare ceramsite in the prior art, it is easy to have problems such as low bulk density, high water absorption rate, and ceramsite strength that cannot meet the requirements of building materials. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a method for preparing ceramsite by using sludge, wherein the prepared ceramsite has low water absorption rate and significantly improved bulk density and cylinder pressure strength.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is:

[0007] A method for preparing ceramsite by using sludge is prepared from the following raw materials in parts by weight:

[0008] 40-60 parts of sludge powder, 10-15 parts of siliceous shale, 10-20 parts of fly ash, 0.5-1 part of CONSOLID444 (C444), and 0.5-1.5 parts of triisopropanolamine, wherein the sludge is sludge powder with a moisture content of about 10%.

[0009] Preferably, the method for preparing ceramsite using sludge according to the present invention is prepared from the following raw materials in parts by weight:

[0010] 40 parts of sludge powder, 10 parts of siliceous shale, 10 parts of fly ash, 0.5 parts of CONSOLID444 (C444), and 0.5 parts of triisopropanolamine.

[0011] Preferably, the method for preparing ceramsite using sludge according to the present invention is prepared from the following raw materials in parts by weight:

[0012] 60 parts of sludge powder, 15 parts of siliceous shale, 20 parts of fly ash, 1 part of CONSOLID444 (C444), and 1.5 parts of triisopropanolamine.

[0013] Preferably, the method for preparing ceramsite by using sludge according to the present invention is prepared from the following raw materials in parts by weight:

[0014] 50 parts of sludge powder, 12.5 parts of siliceous shale, 15 parts of fly ash, 0.75 parts of CONSOLID444 (C444), and 1 part of triisopropanolamine.

[0015] The present invention also provides a method for preparing ceramsite using sludge, comprising the following steps:

[0016] S1. Place the dehydrated sludge in a rotary dryer equipped with a crushing and stirring device, with the hot air inlet temperature at 300-350°C, and dry until the sludge moisture content is about 10% to obtain sludge powder;

[0017] S2, placing sludge powder, siliceous shale, fly ash, CONSOLID444, and triisopropanolamine in a ball mill according to a proportion, dry-milling and mixing to form a uniform powder, and then granulating to obtain ceramsite blank;

[0018] S3, preheating and sintering the ceramsite blank to obtain the ceramsite.

[0019] Furthermore, in step S2, the particle size of the obtained powder is controlled to be between 300 and 400 meshes.

[0020] Furthermore, in step S3, the preheating temperature is 200-300°C, the heating rate is 20-30°C / min, the calcination temperature is 1050-1150°C, and the calcination time is 40-60min.

[0021] The present invention has the following beneficial effects:

[0022] In the present invention, the introduction of CONSOLID444 (C444) can significantly reduce the water absorption rate of ceramsite, and at the same time, it can enrich and improve the internal pore structure of ceramsite in coordination with triisopropanolamine, and significantly improve the mechanical properties of ceramsite.

[0023] The ceramsite obtained by the present invention has a rich pore structure and a bulk density greater than 850kg / cm 3, cylinder pressure strength is greater than 8.0MPa, and 1h water absorption rate is less than 5%, which meets the performance requirements of building materials. DETAILED DESCRIPTION

[0024] In order to make the purpose and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0025] Example 1

[0026] A method for preparing ceramsite using sludge is prepared by the following steps:

[0027] S1. Place the dehydrated sludge in a rotary dryer equipped with a crushing and stirring device, with the hot air inlet temperature at 300-350°C, and dry until the sludge moisture content is about 10% to obtain sludge powder;

[0028] S2. Weigh by weight: 40 parts of sludge powder, 10 parts of siliceous shale, 10 parts of fly ash, 0.5 parts of CONSOLID444 (C444), and 0.5 parts of triisopropanolamine.

[0029] S3, placing sludge powder, siliceous shale, fly ash, CONSOLID444, and triisopropanolamine in a ball mill according to a proportion, dry-milling until the powder particle size is 300-400 mesh, making a uniform powder, granulating, and obtaining ceramsite blank;

[0030] S4, preheating and sintering the ceramsite blank to obtain the ceramsite, wherein the preheating temperature is 200° C., the heating rate is 20° C. / min, the roasting temperature is 1050° C., and the roasting time is 60 min.

[0031] Example 2

[0032] A method for preparing ceramsite using sludge is prepared by the following steps:

[0033] S1. Place the dehydrated sludge in a rotary dryer equipped with a crushing and stirring device, with the hot air inlet temperature at 300-350°C, and dry until the sludge moisture content is about 10% to obtain sludge powder;

[0034] S2. Weigh by weight: 60 parts of sludge powder, 15 parts of siliceous shale, 20 parts of fly ash, 1 part of CONSOLID444 (C444), and 1.5 parts of triisopropanolamine.

[0035] S3, placing sludge powder, siliceous shale, fly ash, CONSOLID444, and triisopropanolamine in a ball mill according to a proportion, dry-milling until the powder particle size is 300-400 mesh, making a uniform powder, granulating, and obtaining ceramsite blank;

[0036] S4, preheating and sintering the ceramsite blank to obtain the ceramsite, wherein the preheating temperature is 300° C., the heating rate is 30° C. / min, the roasting temperature is 1150° C., and the roasting time is 40 min.

[0037] Example 3

[0038] A method for preparing ceramsite using sludge is prepared by the following steps:

[0039] S1. Place the dehydrated sludge in a rotary dryer equipped with a crushing and stirring device, with the hot air inlet temperature at 300-350°C, and dry until the sludge moisture content is about 10% to obtain sludge powder;

[0040] S2. Weigh by weight: 50 parts of sludge powder, 12.5 parts of siliceous shale, 15 parts of fly ash, 0.75 parts of CONSOLID444 (C444), and 1 part of triisopropanolamine.

[0041] S3, placing sludge powder, siliceous shale, fly ash, CONSOLID444, and triisopropanolamine in a ball mill according to a proportion, dry-milling until the powder particle size is 300-400 mesh, making a uniform powder, granulating, and obtaining ceramsite blank;

[0042] S4, preheating and sintering the ceramsite blank to obtain the ceramsite, wherein the preheating temperature is 250° C., the heating rate is 25° C. / min, the roasting temperature is 1100° C., and the roasting time is 50 min.

[0043] Comparative Example 1

[0044] CONSOLID444 (C444) in Example 3 is omitted; the rest of the design is the same as Example 3.

[0045] Comparative Example 2

[0046] The triisopropanolamine in Example 3 is omitted; the rest of the design is the same as Example 3.

[0047] Comparative Example 3

[0048] CONSOLID444 (C444) and triisopropanolamine in Example 3 are omitted; the rest of the design is the same as Example 3.

[0049] Performance Testing

[0050] The bulk density, water absorption rate and cylinder compressive strength of the ceramsite obtained in the examples and comparative examples were tested in accordance with GB / T 17431.2-2010 “Lightweight aggregate and its test methods Part 2: Lightweight aggregate test methods”. The results are shown in Table 1.

[0051] Table 1 Performance of ceramsite

[0052] Group <![CDATA[Bulk density (kg / cm 3 )]]> 1h water absorption rate (%) Cylinder compressive strength (MPa) Example 1 902 0.43 10.1 Example 2 897 0.47 9.8 Example 3 905 0.41 10.3 Comparative Example 1 793 2.7 7.2 Comparative Example 2 796 1.6 6.9 Comparative Example 3 760 5.3 6.5

[0053] As can be seen from Table 1, the bulk density of the ceramsite of the present invention is greater than 850kg / cm 3 The cylinder pressure strength is greater than 8.0MPa and the 1h water absorption rate is less than 5%, which meets the requirements of 900 grade high-strength lightweight aggregate in the national standard "Lightweight aggregate and its test methods Part 1: Lightweight aggregate".

[0054] The bulk density, cylinder pressure strength, and 1h water absorption of the ceramsite of Comparative Example 1 are all higher than those of Comparative Example 3, indicating that CONSOLID444 (C444) can improve particle strength and bulk density and reduce water absorption; the bulk density, cylinder pressure strength, and 1h water absorption of Comparative Example 2 are all higher than those of Comparative Example 3, indicating that the addition of triisopropanolamine can improve particle strength and bulk density and reduce water absorption. At the same time, by comparing the bulk density, cylinder pressure strength, and 1h water absorption of the ceramsite of Comparative Examples 1 and 2 with those of Example 3, it can be found that triisopropanolamine and CONSOLID444 (C444) have a synergistic relationship in improving the particle strength and bulk density of ceramsite and reducing water absorption.

[0055] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for preparing ceramsite using sludge, characterized in that: It is prepared from the following raw materials in parts by weight: 40-60 parts of sludge powder, 10-15 parts of siliceous shale, 10-20 parts of fly ash, 0.5-1 part of CONSOLID444, and 0.5-1.5 parts of triisopropanolamine, wherein the sludge is sludge powder with a moisture content of 10%.

2. The method for preparing ceramsite using sludge as claimed in claim 1, characterized in that: It is prepared from the following raw materials in parts by weight: 40 parts of sludge powder, 10 parts of siliceous shale, 10 parts of fly ash, 0.5 parts of CONSOLID 444, and 0.5 parts of triisopropanolamine.

3. The method for preparing ceramsite using sludge as claimed in claim 1, characterized in that: It is prepared from the following raw materials in parts by weight: 60 parts of sludge powder, 15 parts of siliceous shale, 20 parts of fly ash, 1 part of CONSOLID444, and 1.5 parts of triisopropanolamine.

4. The method for preparing ceramsite using sludge as claimed in claim 1, characterized in that: It is prepared from the following raw materials in parts by weight: 50 parts of sludge powder, 12.5 parts of siliceous shale, 15 parts of fly ash, 0.75 parts of CONSOLID 444, and 1 part of triisopropanolamine.

5. A method for preparing ceramsite using sludge as claimed in any one of claims 1 to 4, characterized in that: The steps include: S1. Place the dehydrated sludge in a rotary dryer with a hot air inlet temperature of 300-350°C and dry until the sludge moisture content is 10% to obtain sludge powder; S2, placing sludge powder, siliceous shale, fly ash, CONSOLID444, and triisopropanolamine in a ball mill according to a proportion, dry-milling and mixing to form a uniform powder, and then granulating to obtain ceramsite blank; S3, preheating and sintering the ceramsite blank to obtain the ceramsite.

6. A method for preparing ceramsite using sludge as claimed in claim 5, characterized in that: In the step S2, the particle size of the obtained powder is controlled to be 300-400 meshes.

7. The method for preparing ceramsite using sludge as claimed in claim 5, characterized in that: In the step S3, the preheating temperature is 200-300°C, the heating rate is 20-30°C / min, the calcination temperature is 1050-1150°C, and the calcination time is 40-60min.