Petroleum fracturing propping agent prepared from solid waste and preparation method of petroleum fracturing propping agent
By using bauxite washing slime and fly ash as raw materials, oil fracturing proppant was prepared, solving the problem of solid waste storage, realizing efficient and low-cost proppant production, and improving product performance and environmental benefits.
Patent Information
- Application Number
- CN202511530377.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-24
- Publication Date
- 2026-02-06
AI Technical Summary
In existing technologies, the stockpiling of bauxite washing slime and fly ash causes environmental burden and resource waste. Traditional fracturing proppant relies on raw materials with high costs and high environmental impact, and lacks a green and sustainable technological path.
Using bauxite washing slime and fly ash as raw materials, and adding high-grade bauxite, a petroleum fracturing proppant is prepared through mixing and sintering. The fly ash is used to supplement SiO2, and the high-grade bauxite is used to increase the alumina content and reduce the sintering temperature, forming a high-strength ceramsite proppant.
It achieves efficient utilization of solid waste, reduces storage risks, lowers manufacturing costs, improves product performance, complies with environmental protection policies, enhances downhole pumping efficiency, and reduces energy consumption.
Smart Images
Figure CN121471899A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of petroleum fracturing proppant preparation technology, specifically, it relates to a petroleum fracturing proppant prepared using solid waste and its preparation method. Background Technology
[0002] In the mining and processing of bulk bauxite, multiple washing processes are required to remove impurities such as clay and silt to improve quality. This process generates a large amount of bauxite washing slime. Currently, this slime is mostly disposed of by damming or direct landfilling, which not only occupies a large amount of land resources in the long term but also poses serious environmental risks. In addition, the slime still retains a certain proportion of valuable components such as alumina and iron oxide, which are not effectively utilized by traditional disposal methods.
[0003] Fly ash is the fine ash and bottom slag collected from the flue gas of coal-fired power plant boilers by a dust collector. Open-air storage can easily cause dust pollution and the spread of toxic chemicals. Discharging it into water systems can cause siltation and harm to human and biological systems. However, the active ingredients in fly ash can improve the strength of its products.
[0004] In contrast to the challenges of solid waste disposal, the demand for fracturing proppant in the oil and gas extraction sector is becoming increasingly urgent. As a core material for oil and gas well fracturing operations, the preparation of traditional fracturing proppant mainly relies on high-grade bauxite, leading to dual pressures on proppant production, both in terms of resources and the environment.
[0005] A significant contradiction exists in the current technological field: on the one hand, the stockpiling of bauxite washing slime and fly ash causes environmental burden and resource waste, and existing disposal methods have low added value and are difficult to scale up; on the other hand, the fracturing proppant industry relies on a high-cost, high-environmental-cost raw material system and lacks a green and sustainable technological path. Therefore, developing a technical solution that can convert bauxite slime and fly ash into high-value-added fracturing proppant has become an urgent need to solve the problem of slime and fly ash stockpiling and optimize the structure of proppant raw materials. Summary of the Invention
[0006] The technical problem this invention aims to solve is to overcome the shortcomings of existing technologies and provide an oil fracturing proppant prepared from solid waste and its preparation method. The method uses bauxite washing slime and fly ash as raw materials, adding a certain amount of high-grade bauxite to increase the alumina content in the mixture. Simultaneously, the fly ash and bauxite slime complement each other, which is beneficial for supplementing the silicon-aluminum framework components required in the ceramsite sintering process, and the production of their glassy phase can reduce the sintering temperature to some extent. Through the synergistic effect of the raw materials, bauxite slime and fly ash, among other solid wastes, can be effectively utilized, achieving dual solid waste utilization, reducing the risk of solid waste stockpiling, and obtaining a ceramsite proppant with high compressive strength and good thermal stability.
[0007] To solve the above-mentioned technical problems, the basic concept of the technical solution adopted by the present invention is as follows: A method for preparing petroleum fracturing proppant using solid waste specifically includes the following steps: S1. The dried stockpile bauxite slime and bauxite are crushed and dry-ground to obtain -400 mesh material; S2. The -400 mesh material obtained in S1 is mixed with fly ash, bentonite, magnesium slag, manganese ore powder and chromium oxide in a certain proportion to form a mixture. The organic binder and sodium hexametaphosphate are added to water to prepare a 0.5% concentration mixed aqueous solution. S3. Add a 0.5% concentration mixed aqueous solution to the mixture obtained in S2 in a granulator to granulate (or granulate directly with water) to obtain green pellets; the green pellets are sieved to obtain -20 to +80 mesh particle size materials, the +20 mesh green pellets are dried, crushed and ground and returned to granulation, and the -80 mesh green pellets are returned to granulation as mother pellets. S4. The -20 to +80 mesh green pellets described in S3 are preheated and dehydrated to remove surface moisture. The dried green pellets are then sintered at a heating rate of 5℃ / min. The temperature is maintained at 500℃ for 1 hour, and then further heated to 1280℃ and maintained for 1.5 hours. After natural cooling, the oil fracturing proppant is obtained, and finished pellets of different specifications are obtained by sieving.
[0008] Further, calculated by weight: 42-50 parts bauxite washing slime, 22-30 parts fly ash, 20-24 parts high-grade bauxite, 1-2 parts bentonite, 1-2 parts magnesium slag, 0.5-1 parts manganese ore powder, 0.1-0.3 parts chromium oxide, 0-0.05 parts organic binder, and 0-0.1 parts sodium hexametaphosphate.
[0009] Furthermore, the main components of the bauxite slime are Al2O3 20-25%, SiO2 25-35%, Fe2O3 8-12%, CaO 4-6%, and MgO 1-3%; the main components of the fly ash are SiO2 30-40%, Al2O3 20-35%, and Fe2O3 4-6%; the content of Al2O3 in the bauxite is 90-93%, and the content of Fe2O3 is <3%; the main components of the magnesium slag are CaO 40-50%, SiO2 25-35%, MgO 7-10%, and Al2O3 2-5%; and the content of MnO2 in the manganese ore powder is ≥50%.
[0010] Further, the main components of the bauxite slime are Al2O3 24.68%, SiO2 33.77%, Fe2O3 11.57%, CaO 5.82%, and MgO 2.89%; the main components of the fly ash are SiO2 38.69%, Al2O3 32.54%, and Fe2O3 4.63%; the bauxite has Al2O3 92.43% and Fe2O3 2.11%; the organic binder may be, but is not limited to, sodium carboxymethyl cellulose (CMC); the magnesium slag has CaO 45.62%, SiO2 28.79%, MgO 8.77%, and Al2O3 2.54%; and the manganese ore powder has MnO2 ≥ 96.13%.
[0011] Furthermore, the mixed aqueous solution is prepared by adding water to an organic binder and sodium hexametaphosphate at a mass ratio of 1:2. The 0.5% concentration of the mixed aqueous solution accounts for 8-15% of the total weight of the mixture, that is, the weight ratio is 8-15:100.
[0012] Furthermore, the granulation process is carried out in a round pot granulator with an inclination angle of 38–45° and a rotation speed of 18–27 r / min.
[0013] Furthermore, the dehydration of the -20 to +80 mesh green pellets was carried out in a drying oven at a temperature of 80 to 100°C. The calcination stage was carried out in a muffle furnace at a heating rate of 5°C / min. The temperature was held at 500°C for 1 hour to fully remove CMC. The calcination stage was carried out when the temperature reached 1280°C and held for 1.5 hours. The pellets were then naturally cooled to below 800°C to obtain petroleum fracturing proppant pellets.
[0014] By adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art.
[0015] This invention has significant benefits, primarily in achieving efficient utilization of two types of solid waste. It uses bauxite washing mud and fly ash as core raw materials to replace traditional high-cost minerals, resulting in a high overall utilization rate of solid waste. This significantly reduces the land occupation and soil and groundwater pollution risks caused by the stockpiling of these two types of solid waste, aligning with the policy of comprehensive utilization of bulk solid waste.
[0016] Meanwhile, the raw material composition can optimize the process through complementary effects: fly ash supplements the lack of SiO2 in the ore slime, and is combined with high-grade bauxite to increase the alumina content; its glassy phase characteristics reduce the sintering temperature by 50-100℃. By precisely proportioning bauxite washing ore slime and fly ash, the silicon-alumina ratio of the mixture is controlled to 1.2-1.5. This ratio can match the "silicon-alumina skeleton" formation conditions required for the sintering of ceramsite proppant. SiO2 acts as a sintering aid to promote liquid phase generation, solving the problem of "insufficient strength" caused by traditional solid waste addition.
[0017] Furthermore, the addition of high-grade bauxite further optimizes the density of the bauxite skeleton, ensuring that the product meets the high-pressure requirements of downhole drilling. This invention exhibits significant energy-saving effects and outstanding economic benefits; solid waste can replace 30-40% of high-grade bauxite, balancing environmental protection and market competitiveness, making it highly valuable in application.
[0018] In summary, this invention uses bauxite slime and fly ash produced from bauxite washing as the main raw materials, and adds a certain amount of high-grade bauxite to increase the alumina content in the materials. Based on the comprehensive utilization of waste materials, a high-performance petroleum fracturing proppant is prepared. This invention reduces the manufacturing cost of petroleum fracturing proppant and provides a new approach to the recycling and utilization of solid wastes such as bauxite slime and fly ash, achieving a low-pollution, low-carbon, and economical production process.
[0019] The specific embodiments of the present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description
[0020] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention, but do not constitute an undue limitation of the invention. Obviously, the drawings described below are merely some embodiments, and those skilled in the art can obtain other drawings based on these drawings without creative effort. In the drawings: Figure 1 This is a schematic diagram of the process flow of the present invention.
[0021] It should be noted that these accompanying drawings and textual descriptions are not intended to limit the scope of the invention in any way, but rather to illustrate the concept of the invention to those skilled in the art by referring to specific embodiments. Detailed Implementation
[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are used to illustrate the present invention, but are not intended to limit the scope of the present invention. Example 1
[0023] A method for preparing petroleum fracturing proppant using solid waste, the proppant comprising the following raw materials in parts by weight: 42 parts bauxite washing slime, 30 parts fly ash, 24 parts high-grade bauxite, 1.55 parts bentonite, 1.45 parts magnesia slag, 0.8 parts manganese ore powder, and 0.2 parts chromium oxide. The specific preparation process is as follows: S1. The dried stockpile bauxite slime and bauxite are mixed, crushed, and dry-milled to obtain -400 mesh material. S2. The -400 mesh material obtained in S1 is mixed with fly ash, bentonite, magnesium slag, manganese ore powder and chromium oxide in a certain proportion to form a mixture. The organic binder CMC and sodium hexametaphosphate are mixed with water at a mass ratio of 1:2 to prepare a 0.5% concentration mixed aqueous solution. S3. The mixture obtained in S2 is granulated by adding a 0.5% concentration mixed aqueous solution in a round pot granulator. The 0.5% concentration mixed aqueous solution accounts for 10% of the total weight of the mixture. The inclination angle of the round pot granulator is 38-45° and the rotation speed is 18-27 r / min to obtain green pellets. The green pellets are sieved to obtain green pellets of -20 to +80 mesh size. The +20 mesh green pellets are dried, crushed, and ground and then returned to granulation. The -80 mesh green pellets are returned to granulation as mother pellets. S4. The -20 to +80 mesh green pellets described in S3 are preheated and dehydrated to remove surface moisture. Then, the green pellets are sintered in a muffle furnace at a heating rate of 5℃ / min. They are held at 500℃ for 1 hour, then heated to 1280℃ and held for 1.5 hours. After natural cooling to below 800℃, petroleum fracturing proppant is obtained. Different sizes of finished pellets are obtained by sieving. Example 2
[0024] The difference between this embodiment and Embodiment 1 above lies in the raw materials of the proppant. In this embodiment, the proppant comprises the following raw materials in parts by weight: The composition includes 45 parts of bauxite washing slime, 27 parts of fly ash, 24 parts of high-grade bauxite, 1.55 parts of bentonite, 1.45 parts of magnesium slag, 0.2 parts of chromium oxide, and 0.8 parts of manganese ore powder. Example 3
[0025] The difference between this embodiment and Embodiment 1 above lies in the raw materials of the proppant. In this embodiment, the proppant comprises the following raw materials in parts by weight: The composition includes 48 parts of bauxite washing slime, 22 parts of fly ash, 24 parts of high-grade bauxite, 1.55 parts of bentonite, 1.45 parts of magnesium slag, 0.2 parts of chromium oxide, and 0.8 parts of manganese ore powder. Example 4
[0026] The difference between this embodiment and Embodiment 1 above lies in the raw materials of the proppant. In this embodiment, the proppant comprises the following raw materials in parts by weight: 50 parts bauxite washing slime, 22 parts fly ash, 24 parts high-grade bauxite, 1.55 parts bentonite, 1.45 parts magnesium slag, 0.2 parts chromium oxide, and 0.8 parts manganese ore powder.
[0027] The pelletizing performance was tested according to SY / T5108-2014, Test Method for Performance of Proppants Used in Hydraulic Fracturing and Gravel Packing Operations. The pelletizing performance indicators of Examples 1-4 above are shown in Table 1.
[0028] Table 1. Pellet Formation Performance Indicators Example Closing pressure / MPa Breakage rate / % <![CDATA[Body density / g / cm 3 > <![CDATA[Apparent density / g / cm 3 > Acid solubility / % sphericity Example 1 52 7.8 1.43 2.81 5.62 ≥0.8 Example 2 52 8.2 1.38 2.82 5.84 ≥0.8 Example 3 52 8.1 1.35 2.77 5.79 ≥0.8 Example 4 52 8.0 1.37 2.79 5.88 ≥0.8 As shown in Table 1, under the process conditions of this invention, it is possible to prepare standard-compliant pellets using only a small amount of high-grade bauxite and two solid wastes. Based on the performance of the pellets, they are a type of low-density, high-strength ceramic proppant. Compared with the conventional ceramic proppant with a bulk density of 1.65–1.85 g / cm³, they can significantly improve downhole pumping efficiency. At the same time, the calcination temperature is 1280℃, which is 70–120℃ lower than the traditional process, achieving low-temperature sintering and reducing energy consumption.
[0029] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-described technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.
Claims
1. A petroleum fracturing proppant prepared using solid waste, characterized in that, It is made by mixing the following raw materials with water, granulating and sintering: The composition includes 42-50 parts of bauxite washing slime, 22-30 parts of fly ash, 20-24 parts of high-grade bauxite, 1-2 parts of bentonite, 1-2 parts of magnesium slag, 0.5-1 part of manganese ore powder, and 0.1-0.3 parts of chromium oxide.
2. The petroleum fracturing proppant prepared from solid waste according to claim 1, characterized in that: The main components of the bauxite slime are Al2O3 20-25%, SiO2 25-35%, Fe2O3 8-12%, CaO 4-6%, and MgO 1-3%. The main components of the fly ash are SiO2 30-40%, Al2O3 20-35%, and Fe2O3 4-6%. The bauxite contains 90-93% Al2O3 and <3% Fe2O3. The main components of the magnesium slag are CaO 40-50%, SiO2 25-35%, MgO 7-10%, and Al2O3 2-5%. The manganese ore powder contains ≥50% MnO2.
3. The petroleum fracturing proppant prepared from solid waste according to claim 1, characterized in that: The water can be replaced by a mixed aqueous solution of an organic binder and sodium hexametaphosphate, wherein the mass ratio of the organic binder to sodium hexametaphosphate is 1:2, and the organic binder is sodium carboxymethyl cellulose.
4. A method for preparing the proppant as described in any one of claims 1-3, characterized in that, Includes the following steps: S1. The dried stockpile bauxite slime and bauxite are crushed and dry-ground to obtain -400 mesh material; S2. The obtained -400 mesh material is mixed with fly ash, bentonite, magnesium slag, manganese ore powder and chromium oxide in a certain proportion to form a mixture. S3. Add water to the mixture in a pellet mill to granulate and obtain green pellets; then the green pellets are screened to obtain green pellets of -20 to +80 mesh size. The +20 mesh green pellets are dried, crushed and ground and then returned to granulation, while the -80 mesh green pellets are returned to pelletization as mother pellets. S4. Preheat and dehydrate the -20 to +80 mesh green pellets, then sinter them, raise the temperature in stages and hold the temperature, and then cool them naturally to obtain the petroleum fracturing proppant.
5. The method according to claim 4, characterized in that: Granulation in S3 is carried out in a round pot granulator with an inclination angle of 38-45° and a rotation speed of 18-27 r / min.
6. The method according to claim 4, characterized in that: In S3, the water used for granulation is replaced by a mixed aqueous solution. The mixed aqueous solution is a 0.5% concentration solution prepared by adding water to organic binder and sodium hexametaphosphate at a mass ratio of 1:
2. The weight ratio of the 0.5% concentration mixed aqueous solution to the mixed materials is 8-15:
100.
7. The method according to claim 4, characterized in that: Sintering in S4 is carried out in a muffle furnace at a heating rate of 5℃ / min. The temperature is held at 500℃ for 1 hour to fully remove CMC and sodium hexametaphosphate. The temperature is then raised to 1280℃ and held for 1.5 hours. The temperature is then naturally cooled to below 800℃ to obtain petroleum fracturing proppant pellets.