Preparation method of microcrystalline glass and microcrystalline glass

Abstract

This invention relates to the field of solid waste treatment technology and discloses a method for preparing microcrystalline glass and the microcrystalline glass itself. The method includes the following steps: (1) mixing gasification slag, oily sludge pyrolysis residue, and optional waste glass powder, and calcining the resulting mixture at 1200-1400℃ for 1-2 hours to obtain molten glass liquid, wherein the Fe2O3 content in the glass liquid is 5-15wt%; (2) annealing and cooling the glass liquid to obtain a glass body; (3) holding the glass body at 600-650℃ for 0.5-2 hours, and then subjecting the obtained intermediate product to heat preservation crystallization treatment, followed by cooling. The method provided by this invention achieves the harmlessness, reduction, and resource utilization of solid waste, and produces microcrystalline glass with excellent performance. In addition, the method is simple to operate, technically mature, suitable for automated production, and can prepare products of various shapes according to actual needs, with good product size control.

Description

Technical Field

[0001] This invention relates to the field of solid waste treatment technology, specifically to a method for preparing microcrystalline glass and the microcrystalline glass itself. Background Technology

[0002] Oily sludge is one of the most significant solid wastes generated in the petroleum industry. It is a complex emulsion formed by the combination of hydrocarbons, water, heavy metals, and solid particles from various petroleum components. Due to its hazardous nature and increasing production, there is growing concern about effective disposal methods for oily sludge. In recent years, there has been increasing attention on the harmless treatment and resource recovery of oily sludge. my country's Ministry of Environmental Protection's "National Hazardous Waste List (2021 Edition)" defines oily sludge as HW08 waste mineral oil and mineral oil-containing waste. Pyrolysis technology for oily sludge involves placing organic raw materials under an inert atmosphere for thermal decomposition (500–1000℃). The final disposal process produces bottom slag and fly ash, i.e., oily sludge pyrolysis residue, which are still considered hazardous waste and must be included in hazardous waste management.

[0003] Currently, global energy resources include coal, oil, and natural gas, with coal being the most widely available and diverse. With the development of my country's coal chemical industry, the installed capacity of coal gasification furnaces is increasing. Gasification slag refers to the solid waste formed by the molten liquid phase of coal and additives under high-temperature conditions, along with residual carbon, after water quenching.

[0004] Microcrystalline glass, also known as glass-ceramic or crystallized glass, is a type of polycrystalline solid material containing a large number of microcrystalline and glassy phases, produced by controlling the crystallization of a base glass with a specific composition during heating. Microcrystalline glass is an important new type of inorganic non-metallic material with high mechanical strength, hardness, and significant corrosion resistance. Different original compositions of microcrystalline glass result in different types of main crystalline phases, such as wollastonite, P-quartz, fluorophlogopite, and spinel. Therefore, by adjusting the composition of the base glass and the processing regime, various microcrystalline glasses meeting predetermined performance requirements can be produced. Research indicates that solid waste vitrification technology holds promise for solving the challenges of harmless, reduced-volume, and resource-based utilization of general solid waste and hazardous waste.

[0005] Patent application CN 108191232 A discloses a method for low-temperature sintering of sludge ceramics. This method involves grinding and mixing dried wastewater sludge from a waterworks with ceramic ingredients to obtain a mixture. The ceramic ingredients include feldspar, calcium oxide, alumina, and carbon powder. The mixture is then held at 1200–1270°C for 2–3 hours, followed by salt bath quenching to obtain a glass material. This glass material is then calcined at 800°C for 2–4 hours to obtain glass ceramics. However, this method, in addition to the wastewater sludge, adds ceramic ingredients accounting for 20–50% of the total raw material weight. This results in higher costs for the microcrystalline glass and fails to fully utilize the wastewater sludge, leading to high treatment costs and long processing times. Furthermore, the addition of carbon powder to the wastewater sludge introduces pores into the resulting glass ceramics, resulting in low density. The addition of carbon powder to the ceramic ingredients may also reduce the efficiency of the electric heating furnace. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a method for preparing microcrystalline glass and the microcrystalline glass itself. This method can achieve the harmlessness, volume reduction, and resource utilization of oily sludge and gasification slag, and the microcrystalline glass produced has excellent performance.

[0007] To achieve the above objectives, the present invention provides a method for preparing microcrystalline glass, the method comprising the following steps:

[0008] (1) Mix gasification furnace slag, oily sludge pyrolysis residue and optional waste glass powder, and calcine the resulting mixture at 1200-1400℃ for 1-2 hours to obtain molten glass liquid, and make the Fe2O3 content in the glass liquid 5-15wt%.

[0009] (2) Anneal and cool the molten glass to obtain a glass body;

[0010] (3) The glass body is kept at 600-650°C for 0.5-2 hours, and then the intermediate product is subjected to heat preservation crystallization treatment and then cooled.

[0011] Preferably, in step (1), based on the total weight of the mixture, the content of the gasification slag is 30-90 wt%, the content of the oily sludge pyrolysis residue is 10-70 wt%, and the content of the waste glass powder is 0-30 wt%.

[0012] Preferably, in step (1), based on the total weight of the mixture, the content of the gasification slag is 40-70 wt%, the content of the oily sludge pyrolysis residue is 20-50 wt%, and the content of the waste glass powder is 10-20 wt%.

[0013] Preferably, in step (1), when the mixture contains gasification slag, oily sludge pyrolysis residue and waste glass powder, the calcination temperature of the mixture is 1200-1300℃.

[0014] Preferably, the oily sludge pyrolysis residue is the residue remaining after the oily sludge has been pyrolyzed and utilized.

[0015] Preferably, the oily sludge is selected from oil tank bottom sludge and / or oily sludge from refinery homogenizing tanks.

[0016] Preferably, the residual carbon content of the oily sludge pyrolysis residue is not higher than 10 wt%.

[0017] Preferably, the oily sludge pyrolysis residue contains SiO2, Al2O3, Na2O, K2O, CaO, MgO, Fe2O3, and TiO2, wherein, based on the total weight of the oily sludge pyrolysis residue, the content of SiO2 is 15-40 wt%, the content of Al2O3 is 10-40 wt%, the content of Na2O is 1-5 wt%, the content of K2O is 0.1-0.9 wt%, the content of CaO is 15-25 wt%, the content of MgO is 1-5 wt%, the content of Fe2O3 is 5-15 wt%, and the content of TiO2 is 0-1 wt%.

[0018] Preferably, the hazardous characteristics of the oily sludge pyrolysis residue are as follows, based on the total weight of the oily sludge pyrolysis residue: V content less than 500 ppm, Cr content less than 200 ppm, Mn content less than 2000 ppm, Co content less than 100 ppm, Ni content less than 300 ppm, Cu content less than 100 ppm, Zn content less than 4000 ppm, As content less than 50 ppm, Se content less than 100 ppm, Ba content less than 3000 ppm, and Pb content less than 20 ppm.

[0019] Preferably, the gasification slag contains SiO2, Al2O3, Na2O, K2O, CaO, MgO, Fe2O3, and TiO2, wherein, based on the total weight of the gasification slag, the content of SiO2 is 23–46 wt%, the content of Al2O3 is 8–15 wt%, the content of Na2O is 0.7–3 wt%, the content of K2O is 0.1–2.3 wt%, the content of CaO is 6.1–24.0 wt%, the content of MgO is 0.5–2.1 wt%, the content of Fe2O3 is 5.6–15.6 wt%, and the content of TiO2 is 0.1–0.65 wt%.

[0020] Preferably, the hazardous characteristics of the gasification slag are as follows: based on the total weight of the gasification slag, the V content is less than 100 ppm, the Cr content is less than 100 ppm, the Mn content is less than 1500 ppm, the Co content is less than 50 ppm, the Ni content is less than 30 ppm, the Cu content is less than 50 ppm, the Zn content is less than 40 ppm, and the Ba content is less than 3500 ppm.

[0021] Preferably, the waste glass powder is obtained by sorting, washing, and mechanically grinding waste glass.

[0022] The waste glass is selected from one or more of the following: medical waste glass, waste household glass, and waste glass for building decoration.

[0023] Preferably, the particle size of the waste glass powder is 100-200 mesh.

[0024] Preferably, in step (1), the heating rate of the calcination step is 3 to 7 °C / min.

[0025] Preferably, in step (2), the annealing temperature is 580-620℃ and the annealing time is 1-2h.

[0026] Preferably, in step (3), the process of heat preservation crystallization includes: heating the intermediate product to 800-900°C and holding it at that temperature for 1-2 hours, and then heating it to 1000-1200°C and holding it at that temperature for 1-2 hours.

[0027] Preferably, in step (3), the heating rate during the heat preservation crystallization process is 4 to 7 °C / min.

[0028] A second aspect of the present invention provides a microcrystalline glass, which is prepared by the method described above.

[0029] The advantages and beneficial effects of this invention are:

[0030] 1. In this invention, the raw materials for preparing microcrystalline glass (gasification slag, pyrolysis residue of oily sludge and waste glass powder) are all solid wastes. This can not only give full play to the potential resources of solid wastes and turn waste into treasure, thereby reducing the production cost of microcrystalline glass, but also reduce the treatment cost of solid wastes.

[0031] 2. This invention uses solid waste such as gasification furnace slag, oily sludge pyrolysis residue and waste glass powder as raw materials, and through the design of preparation steps and process parameters, the resulting microcrystalline glass has a uniform composition, few defects such as pores, excellent performance, and low heavy metal leaching, thus alleviating the pressure of hazardous waste on the environment.

[0032] 3. This method is simple to operate, technically mature, and suitable for mechanical and automated production. It can prepare products of various shapes according to actual needs, and the product size is well controlled. Attached Figure Description

[0033] Figure 1 This is an electron microscope image of the microcrystalline glass prepared in Example 1 of the present invention;

[0034] Figure 2 This is an electron microscope image of the microcrystalline glass prepared in Example 2 of the present invention;

[0035] Figure 3 This is an electron microscope image of the microcrystalline glass prepared in Example 3 of the present invention;

[0036] Figure 4 This is an electron microscope image of the microcrystalline glass prepared in Example 4 of the present invention. Detailed Implementation

[0037] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the invention. The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values; these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, endpoint values ​​of various ranges, endpoint values ​​of various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0038] The method for preparing the microcrystalline glass of the present invention includes the following steps:

[0039] (1) Mix gasification furnace slag, oily sludge pyrolysis residue and optional waste glass powder, and calcine the resulting mixture at 1200-1400℃ for 1-2 hours to obtain molten glass liquid, and make the Fe2O3 content in the glass liquid 5-15wt%.

[0040] (2) Anneal and cool the molten glass to obtain a glass body;

[0041] (3) The glass body is kept at 600-650°C for 0.5-2 hours, and then the intermediate product is subjected to heat preservation crystallization treatment and then cooled.

[0042] This invention uses Fe2O3 as a nucleating agent, and by specifically selecting the raw materials and controlling the amount added, and by making the Fe2O3 content in the glass melt 5-15wt%, it is possible to quickly produce high-performance microcrystalline glass.

[0043] In one specific embodiment, the microcrystalline glass is made from gasification slag and pyrolysis residue of oily sludge.

[0044] In another specific embodiment, the microcrystalline glass is made from gasification slag, pyrolysis residue of oily sludge and waste glass powder. The waste glass powder can supplement the system with SiO2, CaO and other substances to improve the performance of the microcrystalline glass. In addition, the waste glass powder can be used as a flux. By adding the waste glass powder, the melting temperature can be reduced, so that the method has the advantages of energy saving, emission reduction and low production cost.

[0045] In a preferred embodiment, the microcrystalline glass is made from gasification slag, oily sludge pyrolysis residue, and waste glass powder. That is, the preparation process of the mixture involves mixing the gasification slag, oily sludge pyrolysis residue, and waste glass powder to obtain the mixture.

[0046] Preferably, based on the total weight of the mixture, the content of the gasification slag is 30-90 wt%, the content of the oily sludge pyrolysis residue is 10-70 wt%, and the content of the waste glass powder is 0-30 wt%. Specifically, when the raw materials of the mixture are gasification slag and oily sludge pyrolysis residue, the content of the gasification slag in the mixture is 30-90 wt%, and the content of the oily sludge pyrolysis residue is 10-70 wt%. When the raw materials of the mixture also contain waste glass powder, the content of the gasification slag in the mixture is a1, 30wt% ≤ a1 < 90wt%, the content of the oily sludge pyrolysis residue is a2, 10wt% ≤ a2 < 70wt%, and the content of the waste glass powder is not higher than 30wt%. Preferably, based on the total weight of the mixture, the content of the gasification slag is 40-70wt%, the content of the oily sludge pyrolysis residue is 20-50wt%, and the content of the waste glass powder is 10-20wt%.

[0047] Furthermore, in step (1), when the mixture contains gasification slag, oily sludge pyrolysis residue and waste glass powder, the calcination temperature of the mixture is 1200-1300℃.

[0048] In this invention, the oily sludge pyrolysis residue is the residue remaining after the oily sludge has been pyrolyzed and utilized, including bottom ash, fly ash, etc. generated during the pyrolysis process.

[0049] Furthermore, the oily sludge is selected from oil tank bottom sludge and / or oily sludge from refinery homogenizing tanks.

[0050] During the melting process, the residual carbon in the pyrolysis residue of the oily sludge and the gasification slag will generate and release gas. In a specific embodiment, the residual carbon content of the pyrolysis residue of the oily sludge is not higher than 10 wt%, thus reducing the amount of waste gas generated during the preparation of microcrystalline glass.

[0051] The present invention does not limit the amount of residual carbon in the gasification slag, but preferably the gasification slag with a low amount of residual carbon. In a specific embodiment, the selected gasification slag has a residual carbon content of 3 to 28%.

[0052] In a specific embodiment, the oily sludge pyrolysis residue contains SiO2, Al2O3, Na2O, K2O, CaO, MgO, Fe2O3, and TiO2. Based on the total weight of the oily sludge pyrolysis residue, the content of SiO2 is 15–40 wt%, Al2O3 is 10–40 wt%, Na2O is 1–5 wt%, K2O is 0.1–0.9 wt%, CaO is 15–25 wt%, MgO is 1–5 wt%, Fe2O3 is 5–15 wt%, and TiO2 is 0–1 wt%. It should be noted that the above are the main components of the oily sludge pyrolysis residue, not all of the components.

[0053] In a specific embodiment, the gasification slag contains SiO2, Al2O3, Na2O, K2O, CaO, MgO, Fe2O3, and TiO2. Based on the total weight of the gasification slag, the content of SiO2 is 23–46 wt%, Al2O3 is 8–15 wt%, Na2O is 0.7–3 wt%, K2O is 0.1–2.3 wt%, CaO is 6.1–24.0 wt%, MgO is 0.5–2.1 wt%, Fe2O3 is 5.6–15.6 wt%, and TiO2 is 0.1–0.65 wt%. It should be noted that the above are the main components of the gasification slag, not all of them.

[0054] The oily sludge pyrolysis residue is classified as hazardous waste. In a specific embodiment, the hazardous characteristics of the oily sludge pyrolysis residue are as follows: based on the total weight of the oily sludge pyrolysis residue, the V content is less than 500 ppm, Cr content is less than 200 ppm, Mn content is less than 2000 ppm, Co content is less than 100 ppm, Ni content is less than 300 ppm, Cu content is less than 100 ppm, Zn content is less than 4000 ppm, As content is less than 50 ppm, Se content is less than 100 ppm, Ba content is less than 3000 ppm, and Pb content is less than 20 ppm.

[0055] The gasification slag is a general solid waste. In a specific embodiment, the hazardous characteristics of the gasification slag are as follows: based on the total weight of the gasification slag, the V content is less than 100 ppm, the Cr content is less than 100 ppm, the Mn content is less than 1500 ppm, the Co content is less than 50 ppm, the Ni content is less than 30 ppm, the Cu content is less than 50 ppm, the Zn content is less than 40 ppm, and the Ba content is less than 3500 ppm.

[0056] The method provided by this invention can synergistically prepare microcrystalline glass using oily sludge pyrolysis residue (hazardous waste) and gasification slag (general solid waste), thereby realizing the resource utilization, reduction and harmlessness of solid waste, which is of great significance for improving environmental stability.

[0057] In this invention, the waste glass powder is obtained by sorting, washing and mechanically grinding waste glass.

[0058] To facilitate subsequent calcination, the particle size of the waste glass powder in this invention is 100-200 mesh.

[0059] The present invention does not limit the source of the waste glass. In one specific embodiment, the waste glass is selected from one or more of medical waste glass, waste household glass, and waste glass for building decoration.

[0060] In a preferred embodiment, the heating rate of the calcination step is 3-7°C / min. By controlling the heating rate, the resulting microcrystalline glass has better performance.

[0061] In a preferred embodiment, in step (2), the annealing temperature is 580–620°C, specifically, for example, 580°C, 585°C, 590°C, 600°C, 605°C, or 620°C. The annealing time is 1–2 hours, specifically, for example, 1 hour, 1.2 hours, 1.5 hours, or 2 hours.

[0062] In a preferred embodiment, in step (3), the glass body is kept at 630-650°C for 0.5-2 hours.

[0063] In one specific embodiment, the heat preservation crystallization process includes heating the intermediate product to 800–900°C and holding it at that temperature for 1–2 hours. In this embodiment, only one crystallization process is performed.

[0064] In another specific embodiment, the heat preservation crystallization process includes: heating the intermediate product to 800-900°C and holding it at that temperature for 1-2 hours, then heating it to 1000-1200°C and holding it at that temperature for 1-2 hours. In this embodiment, two crystallization processes are performed.

[0065] Preferably, the present invention involves two crystallization processes, namely, a heat preservation crystallization process: the intermediate product is first heated to 800-900°C and kept at that temperature for 1-2 hours, and then heated to 1000-1200°C and kept at that temperature for 1-2 hours. In this way, the microcrystalline glass obtained has a lower heavy metal leaching amount and better performance.

[0066] In a preferred embodiment, in step (3), the heating rate during the heat preservation crystallization process is 4–7 °C / min. Specifically, if there are two crystallization processes, the heating rate for both processes is 4–7 °C / min.

[0067] The microcrystalline glass of the present invention is prepared by the method described above.

[0068] The present invention will be described in detail below through embodiments, but the scope of protection of the present invention is not limited thereto. In the following embodiments, the hazardous characteristics of the oily sludge pyrolysis residue are as follows (based on the total weight of the oily sludge pyrolysis residue): V content less than 500 ppm, Cr content less than 200 ppm, Mn content less than 2000 ppm, Co content less than 100 ppm, Ni content less than 300 ppm, Cu content less than 100 ppm, Zn content less than 4000 ppm, As content less than 50 ppm, Se content less than 100 ppm, Ba content less than 3000 ppm, and Pb content less than 20 ppm; the hazardous characteristics of the gasification slag are as follows (based on the total weight of the gasification slag): V content less than 100 ppm, Cr content less than 100 ppm, Mn content less than 1500 ppm, Co content less than 50 ppm, Ni content less than 30 ppm, Cu content less than 50 ppm, Zn content less than 40 ppm, and Ba content less than 3500 ppm.

[0069] Example 1

[0070] (1) Mix gasification furnace slag, oily sludge pyrolysis residue and waste glass powder, and calcine the resulting mixture at 1300℃ for 2 hours to obtain molten glass liquid;

[0071] The mixture comprises the following components by mass fraction: 60 wt% gasification slag, 30 wt% oily sludge pyrolysis residue and 10 wt% waste glass powder.

[0072] The oily sludge is selected from the oily sludge in the homogenizing tank of an oil refinery. The residual carbon content of the pyrolysis residue of the oily sludge is 0.98%. The main components of the pyrolysis residue of the oily sludge, by weight percentage, include: SiO2 17.21%, Al2O3 39.85%, Na2O 1.37wt%, K2O 0.21%, CaO 19.99%, MgO 2.98%, Fe2O3 11.11%, TiO2 0.38%.

[0073] The residual carbon content of the gasification slag is 27.81%, and the main components of the gasification slag by weight percentage include: SiO2 35.04%, Al2O3 10.85%, Na2O 1.05wt%, K2O 2.04%, CaO 9.38%, MgO 0.77%, Fe2O3 8.07%, TiO2 0.50%;

[0074] The waste glass powder is obtained by sorting, washing, mechanically grinding, and passing the waste glass through a 100-mesh sieve. The waste glass is selected from discarded household glass.

[0075] (2) Pour the glass melt (the Fe2O3 content in the glass melt is about 10wt%) into a mold, place it in 600℃ for annealing treatment for 2h, and then cool and shape it to obtain a glass body;

[0076] (3) The glass body is heated to 630°C at a heating rate of 4°C and held for 1 hour. The intermediate product is heated to 850°C at a heating rate of 4°C and held for 2 hours. Then it is cooled to room temperature to obtain microcrystalline glass.

[0077] Example 2

[0078] (1) Mix gasification furnace slag and oily sludge pyrolysis residue, and calcine the resulting mixture at 1350℃ for 2 hours to obtain molten glass liquid;

[0079] The mixture comprises the following components by mass fraction: 70 wt% gasification slag and 30 wt% oily sludge pyrolysis residue;

[0080] The oily sludge used is the same as that in Example 1;

[0081] The residual carbon content of the gasification slag is 3.63%, and the main components of the gasification slag by weight percentage include: SiO2 41.39%, Al2O3 14.89%, Na2O 1.05wt%, K2O 2.04%, CaO 9.38%, MgO 0.97%, Fe2O3 12.36%, TiO2 0.61%;

[0082] (2) Pour the glass melt (the Fe2O3 content in the glass melt is about 12wt%) into a mold, place it in 600℃ for annealing treatment for 2h, and then cool and shape it to obtain a glass body;

[0083] (3) The glass body is heated to 630°C at a heating rate of 7°C and held for 1 hour. The intermediate product is heated to 850°C at a heating rate of 7°C and held for 2 hours. Then it is cooled to room temperature to obtain microcrystalline glass.

[0084] Example 3

[0085] (1) Mix gasification furnace slag, oily sludge pyrolysis residue and waste glass powder, and calcine the resulting mixture at 1300℃ for 2 hours to obtain molten glass liquid;

[0086] The mixture comprises the following components by mass fraction: 40 wt% gasification slag, 40 wt% oily sludge pyrolysis residue, and 20 wt% waste glass powder; the oily sludge, gasification slag, and waste glass powder used are the same as in Example 1.

[0087] (2) Pour the glass melt (the Fe2O3 content in the glass melt is about 8.9wt%) into a mold, place it in 600℃ for annealing treatment for 2h, and then cool and shape it to obtain a glass body;

[0088] (3) The glass body is heated to 630°C at a heating rate of 5°C and held for 1 hour. The intermediate product is heated to 850°C at a heating rate of 5°C and held for 2 hours. Then it is cooled to room temperature to obtain microcrystalline glass.

[0089] Example 4

[0090] (1) Mix gasification furnace slag, oily sludge pyrolysis residue and waste glass powder, and calcine the resulting mixture at 1300℃ for 2 hours to obtain molten glass liquid;

[0091] The mixture comprises the following components by mass fraction: 40 wt% gasification slag, 50 wt% oily sludge pyrolysis residue, and 10 wt% waste glass powder; the oily sludge and waste glass powder used are the same as in Example 1.

[0092] The residual carbon content of the gasification slag is 6.92%, and the main components of the gasification slag by weight percentage include: SiO2 43.98%, Al2O3 13.36%, Na2O 1.95wt%, K2O 0.62%, CaO 16.64%, MgO 0.87%, Fe2O3 7.85%, and TiO2 0.49%.

[0093] (2) Pour the glass melt (the Fe2O3 content in the glass melt is about 8.7wt%) into a mold, place it in 600℃ for annealing treatment for 2h, and then cool and shape it to obtain a glass body;

[0094] (3) The glass body is heated to 630°C at a heating rate of 5°C and held for 1 hour. The intermediate product is heated to 850°C at a heating rate of 5°C and held for 1 hour. Then, the temperature is increased to 1050°C at a rate of 5°C / min and held for 2 hours. Finally, it is cooled to room temperature to obtain microcrystalline glass.

[0095] Example 5

[0096] (1) Mix gasification furnace slag, oily sludge pyrolysis residue and waste glass powder, and calcine the resulting mixture at 1300℃ for 2 hours to obtain molten glass liquid;

[0097] The mixture comprises the following components by mass fraction: 60 wt% gasification slag, 20 wt% oily sludge pyrolysis residue, and 20 wt% waste glass powder; the oily sludge, gasification slag, and waste glass powder used are the same as in Example 1.

[0098] (2) Pour the glass melt (the Fe2O3 content in the glass melt is about 9wt%) into a mold, place it in 600℃ for annealing treatment for 2h, and then cool and shape it to obtain a glass body;

[0099] (3) The glass body is heated to 630°C at a heating rate of 5°C and held for 1 hour. The intermediate product is heated to 850°C at a heating rate of 5°C and held for 1 hour. Then, the temperature is increased to 1050°C at a rate of 5°C / min and held for 2 hours. Finally, it is cooled to room temperature to obtain microcrystalline glass.

[0100] Example 6

[0101] (1) Mix gasification furnace slag and oily sludge pyrolysis residue, and calcine the resulting mixture at 1350℃ for 2 hours to obtain molten glass liquid;

[0102] The mixture comprises the following components by mass fraction: 40 wt% gasification slag, 50 wt% oily sludge pyrolysis residue and 10 wt% waste glass powder; the oily sludge and gasification slag used are the same as in Example 1.

[0103] (2) Pour the glass melt (the Fe2O3 content in the glass melt is about 10.01wt%) into a mold, place it in 600℃ for annealing treatment for 2h, and then cool and shape it to obtain a glass body;

[0104] (3) The glass body is heated to 630°C at a heating rate of 5°C and held for 1 hour. The intermediate product is heated to 850°C at a heating rate of 5°C and held for 1 hour. Then, the temperature is increased to 1050°C at a rate of 5°C / min and held for 2 hours. Finally, it is cooled to room temperature to obtain microcrystalline glass.

[0105] Example 7

[0106] (1) Mix gasification slag, oily sludge pyrolysis residue and waste glass powder, and calcine the resulting mixture at 1200℃ for 2 hours to obtain molten glass liquid;

[0107] The mixture comprises the following components by mass fraction: 40 wt% gasification slag, 45 wt% oily sludge pyrolysis residue and 15 wt% waste glass powder.

[0108] The oily sludge is selected from oily sludge from homogenizing tanks. The residual carbon content of the pyrolysis residue of the oily sludge is 5.89%. The main components of the pyrolysis residue of the oily sludge, by weight percentage, include: SiO2 27.21%, Al2O3 28.87%, Na2O 1.38wt%, K2O 0.42%, CaO 17.79%, MgO 3.88%, Fe2O3 10.75%, and TiO2 0.5%.

[0109] The residual carbon content of the gasification slag is 18.71%, and the main components of the gasification slag by weight percentage include: SiO2 45.04%, Al2O3 10.85%, Na2O 1.05wt%, K2O 2.05%, CaO 9.38%, MgO 0.72%, Fe2O3 10.85%, and TiO2 0.5%.

[0110] The waste glass powder is obtained by sorting, washing, mechanically grinding, and passing the waste glass through a 100-mesh sieve. The waste glass is selected from discarded household glass.

[0111] (2) Pour the glass melt (the Fe2O3 content in the glass melt is about 10.3wt%) into a mold, place it in 580℃ for annealing treatment for 1.5h, and then cool and shape it to obtain a glass body;

[0112] (3) The glass body is heated to 620°C at a heating rate of 4°C and kept at that temperature for 1 hour. The intermediate product is heated to 800°C at a heating rate of 4°C and kept at that temperature for 2 hours. Then it is cooled to room temperature to obtain microcrystalline glass.

[0113] Example 8

[0114] (1) Mix gasification furnace slag and oily sludge pyrolysis residue, and calcine the resulting mixture at 1300℃ for 1 hour to obtain molten glass liquid;

[0115] The mixture comprises the following components by mass fraction: 60 wt% gasification slag and 40 wt% oily sludge pyrolysis residue;

[0116] The oily sludge is selected from tank bottom sludge. The residual carbon content of the pyrolysis residue of the oily sludge is 5.36%. The main components of the pyrolysis residue of the oily sludge, by weight percentage, include: SiO2 26.87%, Al2O3 28.87%, Na2O 1.38wt%, K2O 0.42%, CaO 17.79%, MgO 3.88%, Fe2O3 12.87%, TiO2 0.5%.

[0117] The residual carbon content of the gasification slag is 6.7%, and the main components of the gasification slag by weight percentage include: SiO2 38.78%, Al2O3 14.56%, Na2O 0.77wt%, K2O 1.04%, CaO 14.7%, MgO 2.06%, Fe2O3 15.6%, and TiO2 0.33%.

[0118] (2) Pour the glass melt (the Fe2O3 content in the glass melt is about 12.7wt%) into a mold, place it in 620℃ for annealing treatment for 1h, and then cool and shape it to obtain a glass body;

[0119] (3) The glass body is heated to 650°C at a heating rate of 7°C and held for 1 hour. The intermediate product is heated to 900°C at a heating rate of 7°C and held for 1 hour. Then, the temperature is increased to 1200°C at a rate of 7°C / min and held for 2 hours. Finally, it is cooled to room temperature to obtain microcrystalline glass.

[0120] Example 9

[0121] The implementation is carried out in accordance with the manner described in Example 4, except that in step (3), the glass body is heated to 630°C at a heating rate of 10°C / min and kept at that temperature for 1 hour.

[0122] Example 10

[0123] The process was carried out in accordance with the method described in Example 4, except that in step (3), the intermediate product was heated to 850°C at a heating rate of 10°C / min and held for 1 hour, and then heated to 1050°C at a rate of 10°C / min and held for 2 hours, and then cooled to room temperature to obtain microcrystalline glass.

[0124] Comparative Example 1

[0125] The mixture was carried out in accordance with the manner described in Example 4, except that Fe2O3 was added externally to make the Fe2O3 content in the mixture 20 wt%.

[0126] Comparative Example 2

[0127] The implementation was carried out in accordance with the manner described in Example 4, except that more waste glass powder was added and gasification slag and oily sludge pyrolysis residue with low iron oxide content were selected so that the Fe2O3 content in the glass melt was 3wt%.

[0128] Comparative Example 3

[0129] The implementation was carried out in accordance with the method described in Example 4, except that only oily pyrolysis sludge was used as raw material. That is, step (1) was: calcining the oily sludge pyrolysis residue at 1300°C for 2 hours to obtain molten glass liquid.

[0130] Test Example 1

[0131] The microcrystalline glass prepared in the examples was characterized using electron microscopy. The microstructure of the microcrystalline glass prepared in Example 1 is as follows: Figure 1 As shown, the microstructure of the glass-ceramic prepared in Example 2 is as follows. Figure 2 As shown, the microstructure of the glass-ceramic prepared in Example 3 is as follows. Figure 3 As shown, the microstructure of the glass-ceramic prepared in Example 4 is as follows. Figure 4 As shown.

[0132] Depend on Figure 1-4 It can be seen that the microcrystalline glass prepared in Examples 1-4 has two microstructures: first, the voids are filled with a glass phase; second, there are uniformly distributed lamellar grains, indicating that the particle size of the prepared microcrystalline glass samples is basically at the micrometer level and the arrangement is relatively uniform. Figure 4 and Figure 1-3 The comparison shows that the microcrystalline glass prepared by two crystallization processes contains thinner and larger multilayered plate-like crystals with disordered orientation, which are evenly and densely distributed, have well-developed crystal morphology, and contain a small amount of glass phase.

[0133] Test Example 2

[0134] The microcrystalline glass prepared in Examples 1-10 and Comparative Examples 1-3 was tested for its physicochemical properties, including relative density (determined by Archimedes method), acid resistance (determined according to JC / T258, ≥96% is considered qualified), alkali resistance (determined according to JC / T258, ≥98% is considered qualified), Mohs hardness (determined according to 6.5.4 of JC / T872-2000), water absorption (determined according to JG / T 463, limit value is 0.05), and Mohs hardness (determined according to 6.5.4 of JC / T872-2000). The test results are shown in Table 1 below.

[0135] Table 1

[0136]

[0137]

[0138] As can be seen from the results in Table 1, the density of the microcrystalline glass prepared in Examples 1-8 is 2.5 g / cm³. 3 The above-mentioned properties, including acid resistance of 98.3% or higher, alkali resistance of 99% or higher, Mohs hardness of 7 or higher, and water absorption of ≤0.05%, all meet the corresponding standards, indicating that the method provided by this invention can produce microcrystalline glass with excellent performance.

[0139] The microcrystalline glass prepared in Comparative Examples 1-3 had acid resistance of 88.0-88.3%, alkali resistance of 88.1-88.7%, and Mohs hardness of 4-5, all of which were unqualified. In addition, the water absorption rate exceeded the limit. This shows that the present invention, through the design of raw materials and various parameters, produces microcrystalline glass with excellent performance.

[0140] Furthermore, the microcrystalline glass prepared in Examples 9-10 had better performance than the comparative example, but worse performance than Examples 1-8, indicating that excessively high heating rates can also affect the performance of microcrystalline glass.

[0141] Test Example 3

[0142] The microcrystalline glass obtained in Examples 1-10 and Comparative Examples 1-3 were used to prepare acid leaching solutions according to the methods specified in 6.2 and 7 of GB / T 30810-2014. The heavy metal leaching amount was tested according to the method specified in GB / T 30810. The results are shown in Table 2 below.

[0143] Table 2

[0144] Example number Cr (mg / L) Ni (mg / L) Mn (mg / L) Zn (mg / L) Example 1 0.11 0.075 0.45 0.18 Example 2 0.15 0.15 0.67 0.20 Example 3 0.10 0.072 0.46 0.17 Example 4 0.03 Not detected Not detected Not detected Example 5 0.04 Not detected Not detected Not detected Example 6 0.12 0.080 0.55 0.68 Example 7 0.09 Not detected 0.12 0.13 Example 8 0.10 Not detected 0.15 0.21 Example 9 0.18 0.18 0.91 0.85 Example 10 0.15 0.17 0.89 0.93 Comparative Example 1 0.25 0.20 0.25 1.1 Comparative Example 2 0.24 0.23 0.23 0.97 Comparative Example 3 0.24 0.22 0.25 1.06

[0145] As shown in Table 2, the leaching concentrations of Cr, Zn, and Ni in Examples 1-10 all meet the requirements of the Chinese national standard (the standard requires that the leaching concentrations of Mn and Zn be less than 1 mg / L, and the leaching concentrations of Cr and Ni be less than 0.2 mg / L). This indicates that the present invention utilizes oily sludge and gasification slag to synergistically prepare microcrystalline glass, reducing the potential pollution risk of heavy metals to the ecological environment. In contrast, the leaching concentrations of Cr and Zn in Comparative Example 1 exceeded the standard requirements, as did the concentrations of Cr and Ni in Comparative Example 2 and Comparative Example 3.

[0146] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method of producing a microcrystalline glass, characterized by, The method includes the following steps: (1) Mix gasification slag, oily sludge pyrolysis residue and optional waste glass powder, and calcine the resulting mixture at 1200~1400℃ for 1~2h to obtain molten glass liquid, and make the Fe2O3 content in the glass liquid 5~15wt%; (2) Anneal the molten glass and cool it to form a glass body; (3) The glass body is kept at 600~650℃ for 0.5~2h, and then the intermediate product is subjected to heat preservation crystallization treatment. The heating rate during the heat preservation crystallization process is 4~7℃ / min, and then cooled. The oily sludge pyrolysis residue contains SiO2, Al2O3, Na2O, K2O, CaO, MgO, Fe2O3, and TiO2. Based on the total weight of the oily sludge pyrolysis residue, the content of SiO2 is 15-40 wt%, Al2O3 is 10-40 wt%, Na2O is 1-5 wt%, K2O is 0.1-0.9 wt%, CaO is 15-25 wt%, MgO is 1-5 wt%, Fe2O3 is 5-15 wt%, and TiO2 is 0-1 wt%. The gasification slag contains SiO2, Al2O3, Na2O, K2O, CaO, MgO, Fe2O3, and TiO2. Based on the total weight of the gasification slag, the content of SiO2 is 23-46 wt%, the content of Al2O3 is 8-15 wt%, the content of Na2O is 0.7-3 wt%, the content of K2O is 0.1-2.3 wt%, the content of CaO is 6.1-24.0 wt%, the content of MgO is 0.5-2.1 wt%, the content of Fe2O3 is 5.6-15.6 wt%, and the content of TiO2 is 0.1-0.65 wt%.

2. The method of claim 1, wherein, In step (1), based on the total weight of the mixture, the content of the gasification slag is 30~90wt%, the content of the oily sludge pyrolysis residue is 10~70wt%, and the content of the waste glass powder is 0~30wt%.

3. The method of claim 1, wherein, In step (1), based on the total weight of the mixture, the content of the gasification slag is 40-70 wt%, the content of the oily sludge pyrolysis residue is 20-50 wt%, and the content of the waste glass powder is 10-20 wt%.

4. The method of claim 1, wherein, In step (1), when the mixture contains gasification slag, oily sludge pyrolysis residue and waste glass powder, the calcination temperature of the mixture is 1200~1300℃.

5. The method of claim 1, wherein, The oily sludge pyrolysis residue is the residue remaining after the oily sludge has been pyrolyzed and utilized.

6. The method of claim 1, wherein, The oily sludge is selected from oil sludge at the bottom of oil tanks and / or oily sludge from homogenizing tanks in oil refineries.

7. The method according to claim 1, characterized in that, The residual carbon content of the pyrolysis residue of the oily sludge is not higher than 10 wt%.

8. The method according to claim 1, characterized in that, The hazardous characteristics of the oily sludge pyrolysis residue are as follows: based on the total weight of the oily sludge pyrolysis residue, the V content is less than 500 ppm, the Cr content is less than 200 ppm, the Mn content is less than 2000 ppm, the Co content is less than 100 ppm, the Ni content is less than 300 ppm, the Cu content is less than 100 ppm, the Zn content is less than 4000 ppm, the As content is less than 50 ppm, the Se content is less than 100 ppm, the Ba content is less than 3000 ppm, and the Pb content is less than 20 ppm.

9. The method according to claim 1, characterized in that, The hazardous characteristics of the gasification slag are as follows: based on the total weight of the gasification slag, the V content is less than 100 ppm, the Cr content is less than 100 ppm, the Mn content is less than 1500 ppm, the Co content is less than 50 ppm, the Ni content is less than 30 ppm, the Cu content is less than 50 ppm, the Zn content is less than 40 ppm, and the Ba content is less than 3500 ppm.

10. The method according to claim 1, characterized in that, The waste glass powder is obtained by sorting, washing, and mechanically grinding waste glass; The waste glass is selected from one or more of the following: medical waste glass, waste household glass, and waste glass for building decoration.

11. The method according to claim 1, characterized in that, The particle size of the waste glass powder is 100-200 mesh.

12. The method according to claim 1, characterized in that, In step (1), the heating rate of the calcination step is 3~7℃ / min.

13. The method according to claim 1, characterized in that, In step (2), the annealing process is carried out at a temperature of 580~620℃ and an annealing time of 1~2h.

14. The method according to any one of claims 1-13, characterized in that, In step (3), the heat preservation crystallization process includes: heating the intermediate product to 800~900℃ and keeping it at that temperature for 1~2 hours.

15. The method according to any one of claims 1-13, characterized in that, In step (3), the heat preservation crystallization process includes: heating the intermediate product to 800~900℃ and holding it for 1~2h, and then heating it to 1000~1200℃ and holding it for 1~2h.

16. A microcrystalline glass, characterized in that, The microcrystalline glass is prepared by the method according to any one of claims 1-15.

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