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본 연구에서는 분쇄 메커니즘이 상이한 볼 밀, 교반 밀, 제트 밀 등의 분쇄기를 사용하여 벽개면이 발달된 고품위의 조립질 규회석의 분쇄 특성을 연구하여 high aspect ratio(HAR) 등급의 규회석을 제조할 수 있는 가능성을 알아보았다. 실험에 사용된 규회석의 결정상은 주로 α-wollastonite였으며, 50.6%의 SiO2, 47.0%의 CaO, 0.6%의 Al2O3, 0.2%의 Fe2O3, 1.1%의 MgO가 함유되어 있었다. 볼 밀로 규회석을 60분에서 120분 동안 분쇄하여 규회석 분체의 평균 입경(d50)을 8.4㎛에서 6.8㎛로 만들면 백색도 90~93, 종횡비 4:1 이하, loose bulk density 0.89~0.86g/cm3, tapped bulk density 1.45~1.36g/cm3이었다. 교반 밀로 규회석을 15분에서 25분 동안 분쇄하여 규회석 분체의 평균입경을 8.8㎛에서 4.9㎛로 만들면 백색도 92~95, 종횡비 6:1~4:1, loose bulk density 0.71~0.60g/cm3, tapped bulk density 1.22~0.90g/cm3이었다. 그러나 제트 밀의 wheel의 속도를 7,000rpm에서 9,000rpm까지 조절하여 규회석 분체의 평균입경을 9.9㎛에서 7.4㎛까지 분쇄한 결과, 백색도 91~92, 종횡비가 14:1이상, loose bulk density는 0.44~0.40g/cm3, tapped bulk density는 0.66~0.62g/cm3로 되어 HAR 등급의 규회석 분체를 제조할 수 있었다.


The characteristics of wollastonite powder ground for manufacturing high aspect ratio(HAR) wollastonite powder by various mills such as a ball mill, stirred ball mill, and jet mill having each different comminution mechanisms were investigated in the study. The α-wollastonite which contains 50.58% SiO2, 47.01% CaO, 0.56% Al2O3, 0.16% Fe2O3, and 1.14% MgO was used for this study. From the comminution of the wollastonite by a ball mill for 60minutes (d50: 8.4㎛) to 120minutes(d50: 6.8㎛), wollastonite powder which has the whiteness of between 90~93.0, the aspect ratio of below 5:1, the loose bulk density of between 0.89~0.85g/cm3, and the tapped bulk density of between 1.45~1.36g/cm3 was obtained. And, through the comminution of the wollastonite by a stirred ball mill for 15minutes(d50: 8.8㎛) to 25minutes(d50: 4.9㎛), wollastonite powder which has the whiteness between 92 and 95, the aspect ratio range of 6:1~4:1, the loose bulk density between 0.71 and 0.60g/cm3, and the tapped bulk density of between 1.22 and 0.90g/cm3 was obtained. Also, by a jet mill under the wheel speed of between 7,000rpm (d50: 9.9㎛) to 9,000rpm(d50: 7.4㎛), wollastonite powder which has the whiteness of between 91~92, the aspect ratio of above 14:1, the loose bulk density of between 0.44~0.40g/cm3, and the tapped bulk density of between 0.66~0.62g/cm3 was obtained. Therefore, it was found that relatively high aspect ratio wollastonite powder can be manufactured by using a jet mill.