Preparation of ceramsite using sludge and method thereof

Abstract

The present application relates to the field of ceramic materials, and particularly relates to a kind of ceramic prepared by sludge and a preparation method thereof, the ceramic is prepared from the following raw materials by weight parts: sludge powder 40-60 parts, siliceous shale 10-15 parts, fly ash 10-20 parts, CONSOLID444 (C444) 0.5-1 part, triisopropanolamine 0.5-1.5 parts, wherein the sludge is sludge powder with moisture content of about 10%.In the present application, the introduction of CONSOLID444 (C444) can significantly reduce the water absorption of ceramic, and its synergy with triisopropanolamine can enrich and improve the internal pore structure of ceramic, significantly improve the mechanical properties of ceramic.The ceramic obtained by the present application has abundant pore structure, bulk density greater than 850kg / cm 3 , cylinder compressive strength greater than 8.0MPa, 1h water absorption less than 5%, meeting the performance requirements of building materials.

Description

Technical Field

[0001] This invention relates to the field of ceramsite materials, specifically to a method for preparing ceramsite using sludge. Background Technology

[0002] Expanded clay aggregate, as the name suggests, is ceramic-like granules, a lightweight and porous building material. Due to its superior physical properties, such as fire resistance, sound insulation, heat insulation, and crack resistance, it is widely used in construction, landscaping, and environmental protection.

[0003] Currently, some foreign studies have reported the use of solid wastes such as riverbed sediment, fly ash, coal gangue, municipal sludge, and red mud as materials for the preparation of ceramsite. If solid wastes can be comprehensively utilized to reduce or eliminate the use of clay and mineral resources, it will bring practical economic and social benefits to the research and development of ceramsite.

[0004] Sludge mainly originates from domestic and industrial wastewater treatment plants. Its composition is approximately 80% water and 20% solids, with about 50% of the solids being organic matter. It functions as an internal fuel and foaming agent in the preparation of high-temperature sintered products, possessing high recycling value. However, current technologies for preparing ceramsite from sludge often suffer from low bulk density, high water absorption, and insufficient strength to meet building material requirements. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a method for preparing ceramsite using sludge. The prepared ceramsite not only has low water absorption but also significantly improved bulk density and cylinder compressive strength.

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

[0007] A method for preparing ceramsite using sludge, comprising the following parts by weight of raw materials:

[0008] The mixture contains 40-60 parts sludge powder, 10-15 parts siliceous shale, 10-20 parts fly ash, 0.5-1 parts CONSOLID444 (C444), and 0.5-1.5 parts 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 sludge powder, 10 parts siliceous shale, 10 parts fly ash, 0.5 parts CONSOLID444 (C444), and 0.5 parts 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 sludge powder, 15 parts siliceous shale, 20 parts fly ash, 1 part CONSOLID444 (C444), and 1.5 parts triisopropanolamine.

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

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

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

[0016] S1. Place the dewatered sludge in a rotary dryer equipped with a crushing and stirring device. The hot air inlet temperature is 300-350℃. Dry the sludge until the moisture content is about 10% to obtain sludge powder.

[0017] S2. Sludge powder, siliceous shale, fly ash, CONSOLID444, and triisopropanolamine are placed in a ball mill according to the specified ratio, and mixed by dry ball milling to form a uniform powder. Then, the powder is granulated to obtain ceramsite raw material.

[0018] S3. The ceramsite blank is preheated and sintered to obtain the ceramsite.

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

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

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

[0022] In this invention, the introduction of CONSOLID444 (C444) can significantly reduce the water absorption rate of ceramsite. At the same time, its synergistic effect with triisopropanolamine can enrich and improve the internal pore structure of ceramsite, significantly enhancing its mechanical properties.

[0023] The ceramsite obtained by this invention has a rich porous structure and a bulk density greater than 850 kg / cm³. 3 The compressive strength of the cylinder is greater than 8.0 MPa, and the water absorption rate in 1 hour is less than 5%, which meets the performance requirements of building materials. Detailed Implementation

[0024] To make the objectives and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0025] Example 1

[0026] A method for preparing ceramsite using sludge, which is obtained through the following steps:

[0027] S1. Place the dewatered sludge in a rotary dryer equipped with a crushing and stirring device. The hot air inlet temperature is 300-350℃. Dry the sludge until the moisture content is about 10% to obtain sludge powder.

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

[0029] S3. Place sludge powder, siliceous shale, fly ash, CONSOLID444, and triisopropanolamine in a ball mill according to the specified ratio, and dry ball mill until the powder particle size is 300-400 mesh to form a uniform powder. Granulate the powder to obtain ceramsite blank.

[0030] S4. The ceramsite blank is preheated and sintered to obtain the ceramsite, wherein the preheating temperature is 200℃, the heating rate is 20℃ / min, the calcination temperature is 1050℃, and the calcination time is 60min.

[0031] Example 2

[0032] A method for preparing ceramsite using sludge, which is obtained through the following steps:

[0033] S1. Place the dewatered sludge in a rotary dryer equipped with a crushing and stirring device. The hot air inlet temperature is 300-350℃. Dry the sludge until the moisture content is about 10% to obtain sludge powder.

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

[0035] S3. Place sludge powder, siliceous shale, fly ash, CONSOLID444, and triisopropanolamine in a ball mill according to the specified ratio, and dry ball mill until the powder particle size is 300-400 mesh to form a uniform powder. Granulate the powder to obtain ceramsite blank.

[0036] S4. The ceramsite blank is preheated and sintered to obtain the ceramsite, wherein the preheating temperature is 300℃, the heating rate is 30℃ / min, the calcination temperature is 1150℃, and the calcination time is 40min.

[0037] Example 3

[0038] A method for preparing ceramsite using sludge, which is obtained through the following steps:

[0039] S1. Place the dewatered sludge in a rotary dryer equipped with a crushing and stirring device. The hot air inlet temperature is 300-350℃. Dry the sludge until the moisture content is about 10% to obtain sludge powder.

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

[0041] S3. Place sludge powder, siliceous shale, fly ash, CONSOLID444, and triisopropanolamine in a ball mill according to the specified ratio, and dry ball mill until the powder particle size is 300-400 mesh to form a uniform powder. Granulate the powder to obtain ceramsite blank.

[0042] S4. The ceramsite blank is preheated and sintered to obtain the ceramsite, wherein the preheating temperature is 250℃, the heating rate is 25℃ / min, the calcination temperature is 1100℃, and the calcination time is 50min.

[0043] Comparative Example 1

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

[0045] Comparative Example 2

[0046] Triisopropanolamine in Example 3 is omitted; the rest of the design is the same as in 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 in 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 according to GB / T 17431.2-2010 "Lightweight aggregates and their test methods - Part 2: Lightweight aggregates test methods". The results are shown in Table 1.

[0051] Table 1 Performance of Ceramsite

[0052] 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 this invention is greater than 850 kg / cm³. 3The compressive strength of the cylinder is greater than 8.0 MPa, and the water absorption rate in 1 hour is less than 5%, which meets the requirements of the national standard "Lightweight Aggregates and Their Test Methods Part 1: Lightweight Aggregates" for grade 900 high-strength lightweight aggregates.

[0054] The bulk density, cylinder compressive strength, and 1-hour water absorption rate of the ceramsite in Comparative Example 1 were all higher than those in Comparative Example 3, indicating that CONSOLID444 (C444) can improve particle strength and bulk density, and reduce water absorption rate. Similarly, the bulk density, cylinder compressive strength, and 1-hour water absorption rate of Comparative Example 2 were all higher than those in Comparative Example 3, indicating that the addition of triisopropanolamine can improve particle strength and bulk density, and reduce water absorption rate. Furthermore, a comparison of the bulk density, cylinder compressive strength, and 1-hour water absorption rate of the ceramsite in Comparative Examples 1 and 2 with those in Example 3 reveals that triisopropanolamine and CONSOLID444 (C444) have a synergistic effect in improving the particle strength and bulk density of ceramsite and reducing water absorption rate.

[0055] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing ceramsite using sludge, characterized in that: Expanded clay aggregate is prepared from the following raw materials in parts by weight: The mixture contains 40-60 parts sludge powder, 10-15 parts siliceous shale, 10-20 parts fly ash, 0.5-1 part CONSOLID444, and 0.5-1.5 parts triisopropanolamine, wherein the sludge powder has a moisture content of 10%. The preparation process includes the following steps: S1. Place the dewatered sludge in a rotary dryer, with the hot air inlet temperature at 300-350℃, and dry it until the sludge moisture content is 10% to obtain sludge powder. S2. Sludge powder, siliceous shale, fly ash, CONSOLID444, and triisopropanolamine are placed in a ball mill according to the specified ratio, and mixed by dry ball milling to form a uniform powder. Then, the powder is granulated to obtain ceramsite raw material. S3. The ceramsite blank is preheated and sintered at a preheating temperature of 200-300℃, a heating rate of 20-30℃ / min, a calcination temperature of 1050-1150℃, and a calcination time of 40-60min to obtain the ceramsite.

2. The method for preparing ceramsite using sludge as described in claim 1, characterized in that: It is prepared from the following raw materials in parts by weight: 40 parts sludge powder, 10 parts siliceous shale, 10 parts fly ash, 0.5 parts CONSOLID444, and 0.5 parts triisopropanolamine.

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

4. The method for preparing ceramsite using sludge as described in claim 1, characterized in that: It is prepared from the following raw materials in parts by weight: 50 parts sludge powder, 12.5 parts siliceous shale, 15 parts fly ash, 0.75 parts CONSOLID444, and 1 part triisopropanolamine.

5. The method for preparing ceramsite using sludge as described in claim 1, characterized in that, In step S2, the particle size of the obtained powder is controlled at 300-400 mesh.