INDUSTRY is one of the important production of coal, the inner universal Kaolin mine containing carbonaceous ore is generally gray - dark gray, massive structure, shell-like fracture, aphanitic structure, worm-like crystals, crystalline order It is a kind of kaolinite coal stone which is found in the carboniferous and Erdie coal seams in northern China. The coal-series kaolin deposits in the area are stable and have a reserve of more than 400 million tons. They are generally treated as waste in the mining process of coal mines. How to use them rationally and turn waste into treasures, the characteristics of specific ores must be studied in detail. Because the coal-based kaolin is distributed in different parts such as the top and bottom of the coal seam, its mineral composition and organic matter content are also different, which affects the quality and processing technology of kaolin. This study systematically studied the characteristics of a coal-bearing kaolin in Huaibei, studied the occurrence of harmful components, and proposed a rational development process and technical route. 1. Test materials and test equipment (a) Samples. It is taken from different layers of Huaibei Xincai Coal Mine, and is classified into 1 #æ ·, 2 #æ ·, and 3 #æ ·, respectively, and 3 # is further divided into 3-1 # samples and 3-2 # samples according to the sampling position. (2) Test equipment. YQ-Z-48A whiteness tester, Hangzhou Lightcom Instrument Development Co., Ltd.; DMAX-IIIA X-ray diffractometer, JEOL Ltd.; Leica DMLP transflective/reverse polarizing microscope, Leica, Germany. Second, the ore material composition (1) Ore chemical composition The chemical composition analysis results of the kaolinite ore are shown in Table 1. Table 1 Chemical composition analysis results of kaolinite ore % Note: Determination by the Chemical Analysis Laboratory of the State Key Laboratory of China University of Geosciences. It can be seen from Table 1 that the SiO 2 is 40.98% to 44.97%, and the Al 2 O 3 is 36. 21% to 38.54%. In addition to the 1 # sample, the other two samples are close to the theoretical value of kaolinite (SiO 2 46.55%, Al 2 O 3 39. 50%); the impurity elements are Fe, Ti, P, Mn, S. Sample # 1 the highest content of total iron, 4.10%, and Fe 2 O 3 0.18%, FeO3.53 %, the ferrous-based; # 2 samples TFe 0.71%, wherein the Fe 2 O 3 0.18%, FeO 0.48 %, the content of ferrous iron is less than 1 # ; 3 # sample (3-1 # and 3-2 # mixed sample) TFe 0.61%, of which Fe 2 O 3 0.33%, FeO 0.25%, the lowest ferrous content; 3 The content of TiO 2 in the ore is similar, ranging from 0.44% to 0.68%. The content of S is very low, 0.008% to 0.03%. P 2 O 5 was lower than the 1 # sample (1.30%), and the other samples were lower (0.05% to 0.51%). The content of Mg, Ca, Na, K, Mn is very low. It can be seen that the kaolinite in Huaibei coal-series has a high content of kaolinite and a low content of impurity elements P and S. The main elements to be removed are Fe and Ti. (2) Mineral composition of ore 1. Observation by polarized light microscope (1) 1 #æ ·. The ore is observed in the form of light gray, and the surface is covered with brown granular iron ore. The ore has a speckled structure and a dense block structure. Microscopically, the kaolinite is a cryptocrystal of fine particles. See Fig. 1(a) and Fig. 1(b), light brown. Generally, the particle size of the monomer particles is <2 μm, and the content is 85% to 90%. The siderite is spherule-shaped, granular, and different in size, the maximum is 1.080mm, the minimum is 0.005mm, generally 0.074-0.526mm, and the sheet is brown with a content of about 10%. A small amount of iron dolomite, charcoal and chlorite, under the microscope, a small black carbonaceous carbon, content 3% to 5%. Figure 11 micrograph of sample # (2) 2 #æ ·. The naked eye is dark gray, cryptocrystalline structure, dense block structure, the kaolinite under the microscope is light brown, the particles are fine, generally <2μm, the content is >95%. A small amount of siderite and pyrite, see Figure 2 (a) and Figure 2 (b), particle size 0.049 ~ 0.088 mm, content 1% ~ 2%. A small amount of carbonaceous material is distributed in kaolinite in small black spots. Very small amount of rutile and zircon, are all from the shaped particles, generally less than 0.010 mm. Figure 2 2 #æ ·çš„microphotograph (3) 3 # samples (3-1 # and 3-2 #æ··æ ·). It was observed by the naked eye as light gray-yellow-light yellow, cryptocrystalline structure, dense block structure. The kaolinite under the microscope is in the form of particles, and the monomer is generally <2 μm and the content is 95%. The other components are a small amount of plant charcoal and siderite <2%, see Figure 3 (a) and Figure 3 (b). Figure 33 micrograph of sample # 2. Ore X-ray diffraction analysis The XRD patterns of different ore samples in the mining area are shown in Figure 4. The diffraction peaks of kaolinite and siderite are visible in Figure 4. 11 #æ ·: The content of siderite is about 10%, which is the result of the identification under the microscope. 22 #æ ·: Single XRD pattern analysis, mainly kaolinite, siderite diffraction peak intensity is very weak, indicating its content <2%. 33 #æ ·: From the XRD pattern analysis, the intensity of the diffraction peak of the siderite is higher than 2 # , and the content of siderite is 3% to 4%. Figure 4 Comparison of XRD patterns of different ore samples K-kaolinite; S-rite According to the chemical composition, microscopic observation and XRD phase analysis, the mineral composition of each ore is shown in Table 2. Table 2 Mineral composition and content of mineral samples % 3. Crystallization characteristics of kaolinite in ore The degree of crystallinity and structural order of kaolinite can be analyzed from the X-ray diffraction pattern of non-oriented kaolinite. The X-ray diffraction pattern of a typical crystallized kaolinite is characterized in that the diffraction peaks of both the base reflection and the non-base reflection are strong and the diffraction peaks are symmetric and well decomposed, especially the diffraction peak of 4.18×10 -10 m. (Index (111) mesh), 3.84×10 -10 m diffraction peak (index (021) mesh) and 2.38×10 -10 m diffraction peak (index (003) The two groups of (131) and (201) diffraction peaks on both sides of the mesh network are also well decomposed. These reflection peaks of highly disordered kaolinite are extremely inconspicuous and are replaced by continuous reflection. The diffraction patterns and data of four kaolin ore samples from Huaibei were analyzed (Table 3). The crystal order of kaolinite can be considered as high crystal order. From the analysis of crystallinity alone, the kaolinite in Huaibei can reach high quality kaolin. According to the standard, the crystal order of kaolin is high-crystallinity kaolinite standard, and the purity can reach more than 90%. However, due to its high iron content, especially siderite, it affects its process index. Greatly reduce the industrial value of kaolin. To improve its value, the ore must be further processed. Table 3: Diffraction characteristics of kaolinite in Huaibei and comparison with other regions. 4. Morphology of kaolinite Fourth, kaolinite morphology In order to understand the grain size and morphology of the unprocessed kaolinite in the ore, SEM analysis was performed on the fresh faces of 1 # , 2 # and 3 # (3-1 # and 3-2 # mixed samples). The three types of ore samples are described as follows: (a) 1 #æ ·. The kaolinite monomer is in the form of a sheet, the maximum is 2.5 μm, generally between 2 and 0.5 μm, the size is uneven, the edges of the sheet are irregular, and the aggregate is laminar or worm-like, as shown in Fig. 5(a), (b) ), (c). The small bright spots (<0.5 μm) in the photo are charcoal. Figure 5 1 SEM image of #原原矿 (2) 2 #æ ·. The flaky kaolinite has a monomer content of at most 3 μm, generally between 0.5 and 2.0 μm, and the size is relatively uniform, and the edges of the particles are uneven. The aggregates are in the form of laminations, see Figures 6(a), (b), (c). Figure 6 2 SEM photo of #原原矿 (3) 3 #æ ·. The flaky kaolinite has a monomer content of at most 1.5 μm, generally between 0.5 and 1.0 μm, and the size is relatively uniform, and the aggregate is laminated. The edges of the particles are relatively straight and some of the particles are visible incomplete hexagons, see Figures 7(a), (b), (c). Figure 73 SEM photograph ore sample # In summary, the 1 # -like and 2 # -like kaolinite characteristics are similar, and the monomer particle size is similar. The crystal grain size of the 3 # -like kaolinite is small, and the crystal form is semi-self-shaped, which is better than the 1 # -like and 2 # -like, but the thickness of the monomer is large. Five, ore whiteness characteristics The occurrence of photochromic ions such as Fe and Ti in kaolinite is the main factor affecting the whiteness of calcination. The results of determination of whiteness of raw ore are shown in Table 4. The results of calcination whiteness measurement of 2 # ore at different temperatures are shown in Table 5. Table 4 Raw ore whiteness test results % Note: Constant temperature 1h. Table 52 # whiteness calcined ore at different temperatures It can be seen from Table 4 that the whiteness after the dry preparation of the ore and the whiteness after calcination are related to the mineral composition of the ore, and the 2 # -like, 3-1 # -like and 3-2 # -like raw ore with high kaolinite content. The whiteness is relatively high, ranging from 56.08 # to 68.76%. After 2 # calcination, the whiteness increased more, reaching 69.40%, and the other two whitenesses did not change significantly. After the 1 # -like calcination of the siderite, the whiteness is reduced because the siderite is calcined and converted to hematite under oxidizing conditions. It can be seen from Table 5 that the whiteness of the ore is continuously increased with the increase of the calcination temperature, and it can reach 70.02% at 1350 °C. Comprehensive analysis, only from the analysis of ore chemical composition, according to the kaolin national standard (GB/T 14563-2008), 2 # , 3 # has reached the following standards: 1 paper industry industrial calcined soil products ZT-Dl and ZT-D2 standards; 2 standards for TT-1 and TT-2 of chemical composition of kaolin products for enamel industry; 3 standards for chemical constituents of calcined soil products for rubber and plastics industry XT-Dl and XT-D2; 4 ceramic industry has reached TC-2 and TC- 3 product standards; 4 standards for calcined soil TL-1, TL-2 and TL-3 products for coatings. However, from the whiteness studies in Tables 4 and 5, according to the kaolin national standard (GB/T14563-2008), the requirements for whiteness of various products, the original ore samples are not up to, and the requirements of the national standard cannot be met after calcination. Therefore, if you want to comprehensively use these four ores, you must conduct research on purification and whitening. Conclusion (1) The main mineral composition of Huaibei coal-series kaolin is kaolinite and siderite. The kaolinite has a high content of 90% to 95%, a high degree of crystal order, etc., mainly in the form of worms, a small monomer particle size, a loose structure between the sheet and the sheet, and a thin sheet, which is easy to carry out. Peel off the sheet and reduce its particle size. (2) The high content of the ore concentrate has a great influence on the whitening of raw ore and calcined products. However, the other gangue minerals in this mine are very small, so how to completely remove the siderite becomes a key factor in the development and utilization of the mine. we are OEM tubing pipeline factory ,we could produing what you need ,for car use ,waiting for your request in anytime. Polyamide brake tube,PA corrugated tube, Automobile wire tube Changchun FAW Sihuan Automobile Pipe Co,Ltd , https://www.automobilepipe.com
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