Method for preparing basalt fiber by modifying basalt ore with lithium extraction solid waste raw slag

Abstract

The invention discloses a method for preparing basalt fibers from lithium extraction solid waste original slag modified basalt ores, which can effectively utilize the lithium extraction solid waste original slag modified basalt ores to prepare the basalt fibers through a wire drawing production process. The method comprises the following steps: mixing powdery lithium extraction solid waste raw slag and powdery basalt ore, and uniformly stirring to form a mixture raw material; the method comprises the following steps: adding a mixture raw material into a kiln by a charging machine, heating the mixture raw material to melt the mixture raw material into a flow-state melt, homogenizing the melt in the kiln, feeding the homogenized melt into a material channel, entering a bushing plate, forming fibers through the bushing plate, and drawing by a drawing machine to prepare the basalt fibers.

Description

Technical Field

[0001] The invention relates to the utilization of lithium extraction solid waste slag and basalt fiber, and in particular to a method for preparing basalt fiber by modifying basalt ore with lithium extraction solid waste slag. Background Art

[0002] In recent years, with the rapid development of the lithium battery industry at home and abroad, the market demand for lithium resources has grown rapidly. At present, lithium resources mainly come from lithium ore and salt lakes. Lithium ores are mainly spodumene and lithium mica. Among them, the spodumene sulfuric acid roasting method will produce 7 to 10 tons of solid waste slag for every ton of lithium salt (lithium carbonate) produced. The country produces more than 5 million tons of solid waste slag every year, which has certain harm to the environment. Technicians in this field usually desulfurize the solid waste slag from lithium extraction to generate desulfurized lithium slag (also known as silicon aluminum powder, with high content of SiO2 and Al2O3, commonly used as glass fiber raw material) and by-products (i.e., iron-rich secondary slag). Due to the large amount of sulfur element (SOx is 6 to 12%) in the solid waste slag from lithium extraction by sulfuric acid roasting, it affects the application, and the by-product (i.e., iron-rich secondary slag) has a large amount of iron oxide enrichment (T Fe2O3: 2 to 10%) and cannot be used in the field of glass fiber and is discarded.

[0003] The production of basalt fiber uses basalt ore as raw material. However, not all basalt ores can be directly used as raw materials for the industrial production of basalt fiber. This is mainly because the content of SiO2, Al2O3 and other chemical components in some basalt ores is relatively low, resulting in low high-temperature viscosity of the melt and high crystallization temperature, which in turn affects the wire drawing production process and makes it impossible to smoothly produce continuous basalt fiber. Basalt ores like this are widely distributed in my country and have very large reserves, but they cannot be used to produce continuous basalt fibers. The industry urgently needs modification technology for this type of basalt ore raw materials to make them suitable for use as raw materials for wire drawing production. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a method for preparing basalt fiber by modifying basalt ore with lithium extraction solid waste slag, which can effectively utilize lithium extraction solid waste slag to modify basalt ore and make basalt fiber through a wire drawing production process.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] A method for preparing basalt fiber by modifying basalt ore with the original residue of lithium extraction solid waste, comprising the following steps: mixing powdery original residue of lithium extraction solid waste and powdery basalt ore, and stirring evenly to form a mixture raw material; adding the mixture raw material into a kiln by a feeder, heating the mixture raw material to melt and fuse it into a fluid molten material, homogenizing the molten material in the kiln, flowing the homogenized molten material into a runner, entering a spinneret, forming fibers through the spinneret, and drawing the fibers by a wire drawing machine to make basalt fiber.

[0007] As a preferred example, the original residue of lithium extraction solid waste is the solid waste generated during the process of extracting lithium resources from lithium ore; forming the mixture raw material includes: directly mixing the powdery original residue of lithium extraction solid waste and powdery basalt ore, and stirring evenly to form the mixture raw material; the mass ratio of the powdery original residue of lithium extraction solid waste to the powdery basalt ore is 5-20:80-95; or, before mixing with the powdery basalt ore, the original residue of lithium extraction solid waste is first subjected to flotation desulfurization treatment to generate desulfurized lithium slag and iron-rich secondary slag, mixing the powdery iron-rich secondary slag and powdery basalt ore, and stirring evenly to form the mixture raw material; the content of iron oxide substances in the iron-rich secondary slag is higher than that in the original residue of lithium extraction solid waste; the mass ratio of the powdery iron-rich secondary slag to the powdery basalt ore is 5-20:80-95.

[0008] As a preferred example, the basalt ore is natural basalt ore; the working temperature of the kiln is 1450-1550 °C; heating the mixture raw material means: heating the mixture raw material by any one or a combination of two methods of flame heating and electric heating; the difference △T between the fiber-forming temperature and the crystallization temperature of the molten material obtained after melting is greater than or equal to 50 °C.

[0009] As a preferred example, the basalt ore is neutral, basic or ultrabasic volcanic rock ore, and the mass percentages of the main components in the volcanic rock ore are:

[0010] SiO2: 40.0-54.0%;

[0011] Al2O3: 10.0-16.0%.

[0012] As a preferred example, the mass percentages of the main components in the original residue of lithium extraction solid waste are:

[0013] SiO2: 50-65%;

[0014] Al2O3: 17-27%;

[0015] SOx: 6-12%;

[0016] The loss on ignition LOI of the original residue of lithium extraction solid waste is 5-16%.

[0017] As a preferred example, the iron-rich secondary slag obtained after the flotation desulfurization treatment of the original lithium-extracting solid waste residue has the following main component mass percentages:

[0018] SiO2: 60 - 67%;

[0019] Al2O3: 21 - 27%;

[0020] T Fe2O3: 2 - 10%;

[0021] SOx: 0.5 - 2%;

[0022] The loss on ignition LOI of the iron-rich secondary slag is 2 - 5%.

[0023] As a preferred example, the basalt ore contains the following components by mass percentage:

[0024] SiO2: 52.06%;

[0025] Al2O3: 15.74%;

[0026] MgO: 6.93%;

[0027] CaO: 8.53%;

[0028] T Fe2O3: 10.49%;

[0029] Na2O: 3.27%;

[0030] The rest is the balance;

[0031] The original lithium-extracting solid waste residue contains the following components by mass percentage:

[0032] SiO2: 54.80%;

[0033] Al2O3: 22.52%;

[0034] MgO: 0.18%;

[0035] CaO: 5.05%;

[0036] T Fe2O3: 1.13%;

[0037] TiO2: 0.10%;

[0038] K2O: 0.50%;

[0039] SOx: 9.6%;

[0040] The loss on ignition LOI of the original lithium-extracting solid waste residue is 5.32%;

[0041] The rest is the remainder.

[0042] As a preferred example, the mass ratio of the powdered lithium-extracted solid waste raw slag to the powdered basalt ore is 1:9; the working temperature of the leakage plate is 1350 °C.

[0043] As a preferred example, the basalt ore contains the following components by mass percentage:

[0044] SiO2: 43.42%;

[0045] Al2O3: 14.00%;

[0046] MgO: 8.96%;

[0047] CaO: 9.13%;

[0048] T Fe2O3: 12.82%;

[0049] Na2O: 3.47%;

[0050] TiO2: 2.99%;

[0051] K2O: 1.69%;

[0052] The rest is the remainder;

[0053] The iron-rich secondary slag contains the following components by mass percentage:

[0054] SiO2: 63.54%;

[0055] Al2O3: 24.75%;

[0056] MgO: 0.44%;

[0057] CaO: 1.29%;

[0058] T Fe2O3: 2.95%;

[0059] TiO2: 0.25%;

[0060] K2O: 1.08%;

[0061] SOx: 0.5%;

[0062] The loss on ignition LOI of the iron-rich secondary slag: 3.83%;

[0063] The rest is the remainder.

[0064] As a preferred example, the mass ratio of the iron-rich secondary slag to the powdered basalt ore is 1:9; the working temperature of the leakage plate is 1360 °C.

[0065] Compared with the prior art, the method for preparing basalt fiber by using the original slag of lithium extraction solid waste to modify basalt ore of the present invention can effectively utilize the original slag of lithium extraction solid waste to modify basalt ore and produce basalt fiber through a wire drawing production process. The method includes the following steps: mixing powdery original slag of lithium extraction solid waste and powdery basalt ore, and stirring evenly to form a mixture raw material; adding the mixture raw material into a kiln by a feeder, heating the mixture raw material to melt and fuse it into a fluid molten material, and homogenizing the molten material in the kiln. The homogenized molten material flows into a runner, enters a spinneret, forms fibers through the spinneret, and is drawn by a wire drawing machine to produce basalt fiber. In addition, the original slag of lithium extraction solid waste can be first subjected to desulfurization treatment to generate desulfurized lithium slag and powdery iron-rich secondary slag, and the powdery iron-rich secondary slag and powdery basalt ore are mixed and stirred evenly to form a mixture raw material. The original slag of lithium extraction solid waste and the iron-rich secondary slag can provide raw materials of SiO2 and Al2O3 compounds with higher content for modifying basalt ore with less Al2O3 and SiO2, improve the high-temperature viscosity parameter of the basalt ore melt, and adjust it to a suitable degree for wire drawing. Specific Embodiment

[0066] The technical solution of the present invention will be described in detail below.

[0067] A method for preparing basalt fiber by using the original slag of lithium extraction solid waste to modify basalt ore according to an embodiment of the present invention includes the following steps:

[0068] Mix powdery original slag of lithium extraction solid waste and powdery basalt ore, and stir evenly to form a mixture raw material; add the mixture raw material into a kiln by a feeder, heat the mixture raw material to melt and fuse it into a fluid molten material. Preferably, the working temperature of the kiln is 1450-1550°C. Homogenize the molten material in the kiln. A uniform and stable melt is beneficial to the stability of the wire drawing operation. The homogenized molten material flows into a runner, enters a spinneret, forms fibers through the spinneret, and is drawn by a wire drawing machine to produce basalt fiber.

[0069] In the above preparation method, the original slag of lithium extraction solid waste is a solid waste generated during the process of extracting lithium resources from lithium ore. The method of the present application is to reuse the solid waste, turn waste into treasure, and realize the circular use of resources. During the process of preparing basalt fiber, the sulfur-containing tail gas generated by adding the original slag of lithium extraction solid waste is absorbed by denitrification and desulfurization equipment on the tail gas discharge pipeline of the production device to meet the gas emission standard.

[0070] In the above preparation method, there are two methods for forming the mixture raw material:

[0071] The first method is as follows: directly mix the powdered lithium-extracted solid waste raw residue with powdered basalt ore and stir evenly to form a mixture raw material. In this method, the mass ratio of the powdered lithium-extracted solid waste raw residue to the powdered basalt ore is 5-20:80-95.

[0072] The second method is as follows: before the lithium-extracted solid waste raw residue is mixed with the powdered basalt ore, it is first subjected to flotation desulfurization treatment to generate desulfurized lithium slag and by-products. The by-product is iron-rich secondary slag. Mix the powdered iron-rich secondary slag with the powdered basalt ore and stir evenly to form a mixture raw material. In this method, the mass ratio of the powdered iron-rich secondary slag to the powdered basalt ore is 5-20:80-95. The content of iron oxide substances in the iron-rich secondary slag is higher than that in the lithium-extracted solid waste raw residue.

[0073] In the above two methods, the first method is to directly modify the basalt ore with the lithium-extracted solid waste raw residue, and the second method is to modify the basalt ore with the powdered iron-rich secondary slag generated by the flotation desulfurization treatment of the lithium-extracted solid waste raw residue.

[0074] The lithium-extracted solid waste raw residue is a mineral substance with relatively high SiO2 and Al2O3 contents. The SiO2 content in the lithium-extracted solid waste raw residue is 50-65%, the Al2O3 content is 17-27%, and it also contains about 10% of SOx. Most of the sulfur compounds will be removed during the flotation desulfurization process. The lithium-extracted solid waste raw residue is an ideal mineral substance with high SiO2 and Al2O3 contents and an ideal modifying substance for low-viscosity basalt ore.

[0075] At the same time, the SiO2 content in the iron-rich secondary slag, one of the products after the flotation desulfurization treatment of the lithium-extracted solid waste raw residue, is about 60-67%, the Al2O3 content is about 21-27%, and the TFe2O3 content is 2-10%. The Fe2O3 content in basalt ore and basalt fiber is relatively high. Therefore, the iron-rich secondary slag is also an ideal mineral substance with high SiO2 and Al2O3 contents and an ideal modifying substance for low-viscosity basalt ore. High-temperature viscosity data of basalt ore melt are obtained through a high-temperature viscometer. When the temperature corresponding to the logarithm of the fiber-forming viscosity lgη = 2.5 is less than 1300 °C, the high-temperature viscosity is low, and the temperature difference ΔT between the fiber-forming temperature and the crystallization temperature < 50 °C, which is low-viscosity basalt ore. The fiber-forming temperature is the temperature corresponding to the logarithm of the fiber-forming viscosity lgη = 2.5.

[0076] The SiO2 content in the original lithium-extracting solid waste slag and the iron-rich secondary slag is about 50-67%, and the Al2O3 content is about 17-27%, which can provide relatively high contents of SiO2 and Al2O3. The original lithium-extracting solid waste slag and the iron-rich secondary slag can provide raw materials of SiO2 and Al2O3 compounds with relatively high contents for modifying basalt ores with less Al2O3 and SiO2, improve the high-temperature viscosity parameters of the basalt ore melt, and adjust it to a suitable degree for wire drawing. The original lithium-extracting solid waste slag and the iron-rich secondary slag are suitable as ingredients for modifying basalt ores.

[0077] The method of this embodiment uses the original lithium-extracting solid waste slag or the iron-rich secondary slag after the original lithium-extracting solid waste slag is treated by flotation desulfurization as a modifier, mixes it with the natural basalt ore raw material, improves the performance of the basalt melt with low silicon and aluminum contents, enables it to carry out wire drawing production, and prepares basalt fibers. By increasing the contents of SiO2 and Al2O3 in the natural basalt ore, the high-temperature viscosity of its melt is increased, the temperature corresponding to the fiber-forming viscosity is increased, and it is higher than the crystallization temperature, so that the temperature difference ΔT between the fiber-forming temperature and the crystallization temperature is ≥50 °C, which is beneficial to wire drawing operations.

[0078] In the method of this embodiment, the basalt ore is a natural basalt ore. Especially for natural basalt ores with low silicon and aluminum contents, through the method of this embodiment, they are modified, so that the modified basalt ores can be wire drawn to make basalt fibers.

[0079] Preferably, in the method of this embodiment, heating the mixture raw material means: heating the mixture raw material by any one or a combination of two of flame heating and electric heating.

[0080] Preferably, in the method of this embodiment, the difference between the fiber-forming temperature and the crystallization temperature of the melt obtained after melting is greater than or equal to 50 °C. This reduces the risk of crystallization at the spinneret, avoids broken ends and flying filaments caused by crystallization, improves the stability of wire drawing operations, and enables the wire drawing process to proceed smoothly.

[0081] Preferably, the basalt ore is a neutral, basic or ultrabasic volcanic rock ore. Some neutral, basic and ultrabasic volcanic rock ores are all natural basalt ores with low contents of SiO2 and Al2O3, and are also natural basalt ores with low high-temperature viscosity. Such ores are not suitable as raw materials for direct wire drawing. The mass percentages of the main components in the basalt ore are:

[0082] SiO2: 40.0-54.0%;

[0083] Al2O3: 10.0-16.0%.

[0084] The basalt ore is selected from natural basalt ores, and its main components include SiO2 and Al2O3.

[0085] Preferably, the mass percentages of the main components in the lithium extraction solid waste slag in the above embodiment are:

[0086] SiO2: 50-65%;

[0087] Al2O3: 17-27%;

[0088] SOx: 6-12%;

[0089] The loss on ignition (LOI) of the lithium extraction solid waste slag is 5-16%.

[0090] In this preferred embodiment, SOx is sulfur oxides contained in lithium extraction solid waste slag.

[0091] Preferably, the iron-rich secondary slag obtained after the lithium extraction solid waste slag is subjected to flotation desulfurization treatment has the following main components in percentage by weight:

[0092] SiO2: 60-67%;

[0093] Al2O3: 21-27%;

[0094] T Fe2O3: 2-10%;

[0095] SOx: 0.5-2%;

[0096] The loss on ignition (LOI) of the iron-rich secondary slag is 2-5%.

[0097] In this preferred example, SOx is sulfur-containing oxides in the iron-rich secondary slag after flotation desulfurization of the lithium-extracting solid waste slag. The mass content of SiO2 in the iron-rich secondary slag is 60-67%, and the mass content of Al2O3 is 21-27%. The higher the content of these two components in the iron-rich secondary slag, the more conducive it is to improve the viscosity of low-viscosity basalt.

[0098] The present invention modifies neutral, basic and ultrabasic basalt ore (volcanic rock) powders with low SiO2 and Al2O3 content in chemical composition, low high-temperature viscosity of melt and high crystallization temperature by adding powdered lithium extraction solid waste slag or iron-rich secondary slag (by-product of desulfurization lithium slag), and stirs and mixes the powder mixture evenly. Due to the modification of basalt by lithium extraction solid waste slag or iron-rich secondary slag, the content of SiO2 and Al2O3 is increased, the high-temperature viscosity of melt is increased, the crystallization temperature of melt is reduced, and the drawing operation temperature △T range is increased, so that it is suitable for wire drawing production and continuous basalt fiber products can be produced.

[0099] The following experiments are conducted to verify that the technical solution of the present invention can be implemented.

[0100] There are two types of natural basalt ores in the experiment. One type of natural basalt ore is mined from Hebei Province and is denoted as 1#. The other type of natural basalt ore is basic basalt ore, mined from Shandong Province and denoted as 2#.

[0101] The original slag of lithium extraction solid waste in the experiment comes from Tianqi Lithium Industry Co., Ltd.

[0102] For some of the above-mentioned original slag of lithium extraction solid waste, a flotation desulfurization treatment process is adopted to obtain desulfurized lithium slag and by-products (iron-rich secondary slag). Specifically, in the original slag solution, calcium carbonate is added to convert sulfur elements into calcium sulfate. At the same time, a surfactant is added to generate bubbles, enabling calcium sulfate to be enriched together with the bubble layer and separated (desulfurized) to form gypsum product slag. Next, a magnetic separation device is used to enrich iron oxides to form by-products, namely iron-rich secondary slag. The slag obtained after the desulfurization and iron removal steps of the original slag of lithium extraction solid waste is desulfurized lithium slag. The production cost of desulfurized lithium slag is much higher than that of the original slag of lithium extraction solid waste.

[0103] Using GB / T 43309-2023 Determination of Chemical Elements in Glass Fibers and Their Raw Materials - X-ray Fluorescence Spectrometry and GB / T1549-2008 Chemical Analysis Methods for Fiber Glass, the main components and contents of the above two types of natural basalt ores are detected, and the detection results are shown in Table 1. The same method is used to detect the main components and contents of the original slag of lithium extraction solid waste, desulfurized lithium slag, and iron-rich secondary slag, and the detection results are shown in Table 2. The X-ray fluorescence spectrometer (XRF) is an X-ray fluorescence spectrometer produced by SPECTRO of Germany. The inductively coupled plasma emission spectrometer (ICP) is an Agilent 5110 ICP-OES produced by the United States.

[0104] Loss on ignition is a parameter in the process of testing components. It is a part of the substance composition. When calculating the content of the main components of a substance at high temperature, the loss on ignition data should be removed and the percentage content should be recalculated. Using the loss on ignition test method in GB / T 1549-2008 Chemical Analysis Methods for Fiber Glass, the loss on ignition (LOI) of the above two types of natural basalt ores is measured, and the measurement results are shown in Table 1. The same method is used to measure the loss on ignition (LOI) of the original slag of lithium extraction solid waste, desulfurized lithium slag, and iron-rich secondary slag, and the measurement results are shown in Table 2. The muffle furnace used in the measurement is the SX2-4-13 model produced by Nanjing Huiheng Scientific Instruments Co., Ltd. The manufacturer of the electronic balance is Mettler-Toledo, and the model is ML204.

[0105] Table 1

[0106] Component Name Basalt Ore 1# Basalt Ore 2# <![CDATA[SiO2]]> 52.06 43.42 <![CDATA[Al2O3]]> 15.74 14.00 MgO 6.93 8.96 CaO 8.53 9.13 <![CDATA[T Fe2O3]]> 10.49 12.82 <![CDATA[TiO2]]> 1.45 2.99 <![CDATA[K2O]]> 0.66 1.69 <![CDATA[Na2O]]> 3.27 3.47 MnO 0.15 0.21 <![CDATA[SO x > 0.21 0.03 <![CDATA[P2O5]]> 0.03 0.45 LOI 0.28 2.2 Total 99.80 99.37

[0107] T Fe2O3 represents the total content of iron oxides in basalt ore.

[0108] Table 2

[0109] Original Residue of Lithium Extraction Solid Waste Secondary Slag Rich in Iron Desulfurized Lithium Slag <![CDATA[SiO2]]> 54.80 63.54 68.8 <![CDATA[Al2O3]]> 22.52 24.75 26.8 MgO 0.18 0.44 0.16 CaO 5.05 1.29 0.94 <![CDATA[T Fe2O3]]> 1.13 2.95 0.88 <![CDATA[TiO2]]> 0.10 0.25 0.08 <![CDATA[K2O]]> 0.50 1.08 0.69 <![CDATA[SO x > 9.6 0.50 0.5 LOI 5.32 3.83 0.4 Total 99.20 98.63 99.25

[0110] The method for preparing basalt fibers according to the present invention includes four embodiments:

[0111] Embodiment 1

[0112] Mix 100 g of powdered lithium-extracted solid waste raw residue with 900 g of basalt ore 1#. The mass ratio of the powdered lithium-extracted solid waste raw residue to the powdered basalt ore is 1:9. Stir evenly to form a mixture raw material. Feed the mixture raw material into a kiln by a feeder. The temperature of the kiln is 1500 °C. Electric heating is used for the mixture raw material to melt and fuse it into a fluid molten material, and the molten material is homogenized in the kiln. The homogenized molten material flows into a runner and then into a spinneret. The working temperature of the spinneret is 1350 °C. Fibers are formed through the spinneret and drawn by a wire drawing machine to produce basalt fibers.

[0113] Embodiment 2

[0114] Mix 100 g of powdered iron-rich secondary slag with 900 g of basalt ore 1#. The mass ratio of the powdered iron-rich secondary slag to the powdered basalt ore is 1:9. Stir evenly to form a mixture raw material. Feed the mixture raw material into a kiln by a feeder. The temperature of the kiln is 1500 °C. Flame heating is used for the mixture raw material to melt and fuse it into a fluid molten material, and the molten material is homogenized in the kiln. The homogenized molten material flows into a runner and then into a spinneret. The working temperature of the spinneret is 1360 °C. Fibers are formed through the spinneret and drawn by a wire drawing machine to produce basalt fibers.

[0115] Embodiment 3

[0116] Mix 200 g of powdered lithium-extracted solid waste raw residue with 800 g of basalt ore 2#. The mass ratio of the powdered lithium-extracted solid waste raw residue to the powdered basalt ore is 1:4. Stir evenly to form a mixture raw material. Feed the mixture raw material into a kiln by a feeder. The temperature of the kiln is 1450 °C. Electric heating is used for the mixture raw material to melt and fuse it into a fluid molten material, and the molten material is homogenized in the kiln. The homogenized molten material flows into a runner and then into a spinneret. The working temperature of the spinneret is 1320 °C. Fibers are formed through the spinneret and drawn by a wire drawing machine to produce basalt fibers.

[0117] Embodiment 4

[0118] Mix 200 grams of powdered iron-rich secondary slag with 800 grams of basalt ore #2. The mass ratio of the powdered iron-rich secondary slag to the powdered basalt ore is 1:4. Stir evenly to form a mixture raw material. Feed the mixture raw material into a kiln by a feeder. The temperature of the kiln is 1450 °C. Heat the mixture raw material by electricity and flame to melt and fuse it into a fluid molten material, and homogenize the molten material in the kiln. The homogenized molten material flows into a runner and then into a bushing. The working temperature of the bushing is 1330 °C. Fibers are formed through the bushing and drawn by a wire drawing machine to produce basalt fibers.

[0119] Example 5

[0120] Mix 100 grams of powdered lithium-extracted solid waste raw slag with 1900 grams of basalt ore #2. The mass ratio of the powdered lithium-extracted solid waste raw slag to the powdered basalt ore is 1:19. Stir evenly to form a mixture raw material. Feed the mixture raw material into a kiln by a feeder. The temperature of the kiln is 1550 °C. Heat the mixture raw material by flame to melt and fuse it into a fluid molten material, and homogenize the molten material in the kiln. The homogenized molten material flows into a runner and then into a bushing. The working temperature of the bushing is 1350 °C. Fibers are formed through the bushing and drawn by a wire drawing machine to produce basalt fibers.

[0121] Example 6

[0122] Mix 200 grams of powdered iron-rich secondary slag with 1600 grams of basalt ore #2. The mass ratio of the powdered iron-rich secondary slag to the powdered basalt ore is 1:8. Stir evenly to form a mixture raw material. Feed the mixture raw material into a kiln by a feeder. The temperature of the kiln is 1500 °C. Heat the mixture raw material by electricity and flame to melt and fuse it into a fluid molten material, and homogenize the molten material in the kiln. The homogenized molten material flows into a runner and then into a bushing. The working temperature of the bushing is 1345 °C. Fibers are formed through the bushing and drawn by a wire drawing machine to produce basalt fibers.

[0123] Comparative Example 1

[0124] Continuously feed the raw material of basalt ore #1 into a kiln by a feeder. The temperature of the kiln is 1480 °C. Heat the raw material by flame to melt and fuse it into a fluid molten material, and homogenize the molten material in the kiln. The homogenized molten material flows into a runner and then into a bushing. The working temperature of the bushing is 1300 °C. Draw the fibers by a wire drawing machine.

[0125] Comparative Example 2

[0126] The basalt ore 2# raw material is continuously added into the kiln by a feeding machine. The temperature of the kiln is 1480°C. The raw material is electrically heated to melt and fuse into a fluid molten material, and the molten material is homogenized in the kiln. The homogenized molten material flows into the runner and enters the bushing. The working temperature of the bushing is 1195°C, and wire drawing cannot be carried out.

[0127] Comparative Example 3

[0128] 100 grams of powdered desulfurized lithium slag and 900 grams of basalt ore 1# are mixed. The mass ratio of the powdered desulfurized lithium slag to the powdered basalt ore is 1:9; they are stirred evenly to form a mixture raw material; the mixture raw material is added into the kiln by a feeding machine. The temperature of the kiln is 1550°C. The mixture raw material is heated by flame to melt and fuse into a fluid molten material, and the molten material is homogenized in the kiln. The homogenized molten material flows into the runner and enters the bushing. The working temperature of the bushing is 1370°C. Fibers are formed through the bushing and drawn by a wire drawing machine to produce basalt fibers.

[0129] Comparative Example 4

[0130] 200 grams of powdered desulfurized lithium slag and 1600 grams of basalt ore 2# are mixed. The mass ratio of the powdered desulfurized lithium slag to the powdered basalt ore is 1:8; they are stirred evenly to form a mixture raw material; the mixture raw material is added into the kiln by a feeding machine. The temperature of the kiln is 1550°C. The mixture raw material is heated by electricity and flame to melt and fuse into a fluid molten material, and the molten material is homogenized in the kiln. The homogenized molten material flows into the runner and enters the bushing. The working temperature of the bushing is 1350°C. Fibers are formed through the bushing and drawn by a wire drawing machine to produce basalt fibers.

[0131] In the preparation processes of the above 6 examples and 4 comparative examples, the fiber-forming temperature of the molten material obtained after melting is the working temperature of the bushing. A gradient furnace is used to measure the crystallization temperature, and the measurement method is in accordance with Standard No. ASTM C829-81. The measurement results are shown in Table 3. The temperature difference △T is obtained by subtracting the crystallization temperature from the fiber-forming temperature T (lgη = 2.5) of the molten material obtained after melting. If △T is greater than or equal to 50°C, wire drawing is easy; if △T is less than 50°C, wire drawing is difficult. The smaller △T is, the more difficult wire drawing is. When △T is negative, wire drawing is almost impossible.

[0132] Table 3

[0133]

[0134] The chemical composition of basalt ore 1# contains 52.06% SiO2 and 15.74% Al2O3. Meanwhile, the contents of CaO and MgO are high. The fiber forming temperature is 1220-1305°C, the upper limit of crystallization temperature is 1280°C, and the melt drawing operating temperature range △T is 25-(-60)°C, which is relatively narrow. It is judged that crystallization and yarn breakage will occur in the drawing process.

[0135] The chemical composition of basalt ore 2# has an SiO2 content of 43.42% and an Al2O3 content of 14.00%. At the same time, the CaO and MgO contents are high. The fiber forming temperature is 1165-1190°C, the upper limit temperature of crystallization is 1360°C, and the melt drawing operating temperature range △T is: (-170°C) ~ (-195°C). The fiber forming range is a negative number and the range is extremely narrow, making it extremely difficult to judge the drawing process.

[0136] For the above two basalt ores, in order to realize their wire drawing production, the basalt ore raw materials must be formulated, and the direction of the formulation is to increase their high temperature viscosity and reduce their upper limit crystallization temperature. Although the upper limit crystallization temperature of Example 1 is high, the wire drawing temperature is higher, ΔT is 50, which is more conducive to wire drawing operation.

[0137] As shown in Table 3, the ΔT of Comparative Examples 1 and 2 is less than or equal to 20°C, and it is not easy to draw a wire. In particular, the ΔT of Comparative Example 2 is -165°C, and it is almost impossible to draw a wire. The ΔT of Examples 1 to 4 is above 50°C, and it is possible to draw a wire. Although Example 2 can achieve wire drawing, the high fiber forming temperature may affect the life of the bushing.

[0138] As can be seen from Table 3, in basalt ore 1#, after adding lithium extraction solid waste slag, its wire drawing operating temperature range gradually increased from 20°C to 50°C, which was significantly widened, which was conducive to industrial production, but at the same time, the temperature of the leak plate was also increasing. The more lithium extraction solid waste slag was added, the higher the temperature of the leak plate. After adding iron-rich secondary slag, its wire drawing operating temperature range gradually increased from 20°C to 80°C, which was better than adding lithium extraction solid waste slag alone, but at the same time, the temperature increase of the leak plate was basically the same as that of the sample modified with lithium extraction solid waste slag.

[0139] Basalt ore 2#, which is not suitable for direct wire drawing production, has a wire drawing operating temperature range gradually increased from -165℃ to 50℃ after adding lithium extraction solid waste slag, which is significantly wider and conducive to industrial production. After adding iron-rich secondary slag, its wire drawing operating temperature range gradually increased from -165℃ to 70℃, which is better than adding lithium extraction solid waste slag alone, but at the same time, its leak plate rise temperature is basically the same as that of the sample modified with lithium extraction solid waste slag.

[0140] It can be seen from Table 3 that the modification of basalt ore with iron-rich secondary slag has a better effect. Comparing Example 1 and Example 2, for the samples modified with iron-rich secondary slag, the crystallization temperature is lower, the △T range is larger, and the bushing temperature is basically the same. Therefore, the modification of basalt ore with iron-rich secondary slag has a better effect. Comparing Example 2 and Comparative Example 3, as well as Example 6 and Comparative Example 4, the modification effect of basalt ore with iron-rich secondary slag is better than that with desulfurized lithium slag.

[0141] In Example 2 and Comparative Example 3, the mass ratio of iron-rich secondary slag to basalt ore is the same as that of desulfurized lithium slag to basalt ore. The crystallization temperature of Comparative Example 3 is 1310 °C, and the crystallization temperature of Example 2 is 1280 °C. The crystallization temperature of Example 2 is 30 °C lower than that of Comparative Example 3. A lower crystallization temperature is beneficial for the bushing of the drawing die not to be blocked by crystallization, and the drawing operation is more stable. The fiber-forming temperature of Example 2 is 1360 °C, and the fiber-forming temperature of Comparative Example 3 is 1370 °C. The fiber-forming temperature of Example 2 is lower than that of Comparative Example 3. A lower fiber-forming temperature and a lower bushing temperature are beneficial for extending the service life of the bushing. The △T of Example 2 is 80 °C, and the △T of Comparative Example 3 is 60 °C. The △T of Example 2 is greater than that of Comparative Example 3. The larger the △T, the wider the temperature range for the drawing operation, which is beneficial for the operation of the drawing process.

[0142] The iron-rich secondary slag is enriched with iron oxides in its composition, which promotes the melting effect and simultaneously reduces the crystallization temperature, having a good effect on the drawing process.

[0143] Similarly, in Example 6 and Comparative Example 4, the mass ratio of iron-rich secondary slag to basalt ore is the same as that of desulfurized lithium slag to basalt ore. The crystallization temperature of Example 6 is 1290 °C, and the crystallization temperature of Comparative Example 4 is 1300 °C. The crystallization temperature of Example 6 is lower than that of Comparative Example 4. The fiber-forming temperature of Example 6 is 1345 °C, and the fiber-forming temperature of Comparative Example 4 is 1350 °C. The fiber-forming temperature of Example 6 is lower than that of Comparative Example 4. The △T of Example 6 is 55 °C, and the △T of Comparative Example 4 is 50 °C. The △T of Example 6 is greater than that of Comparative Example 4.

[0144] Therefore, the modification of basalt ore with iron-rich secondary slag has a better effect than that with desulfurized lithium slag.

[0145] The above shows and describes the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above specific embodiments. The above specific embodiments and the descriptions in the specification are only for further explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed.

Claims

1. A method for preparing basalt fiber by modifying basalt ore with waste residue from lithium extraction, characterized in that, The method includes the following steps: Mix and stir evenly powdered lithium extraction solid waste raw slag and powdered basalt ore to form a mixture raw material; add the mixture raw material into a kiln by a feeder, heat the mixture raw material to melt and fuse it into a fluid molten material, homogenize the molten material in the kiln, let the homogenized molten material flow into a runner, enter a bushing, form fibers through the bushing, and draw the fibers by a fiber drawing machine to produce basalt fibers.

2. The method according to claim 1, wherein The lithium extraction solid waste raw slag is solid waste generated during the process of extracting lithium resources from lithium ore; Forming the mixture raw material includes: directly mixing and stirring evenly powdered lithium extraction solid waste raw slag and powdered basalt ore to form a mixture raw material; the mass ratio of the powdered lithium extraction solid waste raw slag to the powdered basalt ore is 5-20:80-95; Or, Before the lithium extraction solid waste raw slag is mixed with the powdered basalt ore, it is first subjected to flotation desulfurization treatment to generate desulfurized lithium slag and iron-rich secondary slag, mix and stir evenly the powdered iron-rich secondary slag and the powdered basalt ore to form a mixture raw material; the content of iron oxide substances in the iron-rich secondary slag is higher than that in the lithium extraction solid waste raw slag; the mass ratio of the powdered iron-rich secondary slag to the powdered basalt ore is 5-20:80-95.

3. The method according to claim 1, characterized in that, The basalt ore is natural basalt ore; The working temperature of the kiln is 1450-1550 °C; Heating the mixture raw material means: heating the mixture raw material by any one or a combination of two methods of flame heating and electric heating; The difference △T between the fiber-forming temperature and the crystallization temperature of the molten material obtained after melting is greater than or equal to 50 °C.

4. The method according to claim 1, characterized in that The basalt ore is neutral, basic or ultrabasic volcanic rock ore, and the mass percentages of the main components in the volcanic rock ore are: SiO2: 40.0-54.0%; Al2O3: 10.0-16.0%.

5. The method according to claim 2, characterized in that, The mass percentages of the main components in the lithium extraction solid waste raw slag are: SiO2: 50-65%; Al2O3: 17-27%; SOx: 6-12%; The loss on ignition LOI of the lithium extraction solid waste raw slag: 5-16%.

6. The method according to claim 2, wherein The iron-rich secondary slag obtained after the lithium extraction solid waste raw slag is subjected to flotation desulfurization treatment, and the mass percentages of the main components are: SiO2: 60-67%; Al2O3: 21-27%; T Fe2O3: 2-10%; SOx: 0.5-2%; The loss on ignition LOI of the iron-rich secondary slag: 2-5%.

7. The method according to claim 2, characterized in that, The basalt ore contains the following components by mass percentage: SiO2: 52.06%; Al2O3: 15.74%; MgO: 6.93%; CaO: 8.53%; T Fe2O3: 10.49%; Na2O: 3.27%; The rest is the balance; The lithium extraction solid waste raw slag contains the following components by mass percentage: SiO2: 54.80%; Al2O3: 22.52%; MgO: 0.18%; CaO: 5.05%; T Fe2O3: 1.13%; TiO2: 0.10%; K2O: 0.50%; SOx: 9.6%; The loss on ignition (LOI) of the original lithium-extracted solid waste residue: 5.32%; The rest is the balance.

8. The method according to claim 7, wherein The mass ratio of the powdered original lithium-extracted solid waste residue to the powdered basalt ore is 1:9; the working temperature of the leakage plate is 1350 °C.

9. The method according to claim 2, characterized in that The basalt ore contains the following components by mass percentage: SiO2: 43.42%; Al2O3: 14.00%; MgO: 8.96%; CaO: 9.13%; T Fe2O3: 12.82%; Na2O: 3.47%; TiO2: 2.99%; K2O: 1.69%; The rest is the balance; The iron-rich secondary slag contains the following components by mass percentage: SiO2: 63.54%; Al2O3: 24.75%; MgO: 0.44%; CaO: 1.29%; T Fe2O3: 2.95%; TiO2: 0.25%; K2O: 1.08%; SOx: 0.5%; The loss on ignition (LOI) of the iron-rich secondary slag: 3.83%; The rest is the balance.

10. The method according to claim 9, wherein The mass ratio of the iron-rich secondary slag to the powdered basalt ore is 1:9; the working temperature of the leakage plate is 1360 °C.

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