박리 마쇄 기술을 적용한 폐콘크리트 미분말의 품질 향상 효과

Quality Improvement Effect of Waste Concrete Fine Powder by Applying Exfoliation Technology

Since the main components of waste concrete fine powder generated in the process of converting waste concrete into recycled aggregate are essentially the same as the main ingredients of cement-clinker, it is possible to use it as a raw material for cement. In addition, because waste concrete fine powder is a decarbonated salt, using it as a raw material for cement clinker is a very important carbon-neutral technology that can be expected to reduce process-derived carbon emission generated during cement manufacturing. However, waste concrete fine powder has a low calcium oxide content of around 10%, so its usability as a clinker raw material is very low. In order to use waste concrete fine powder as a raw material for clinker, the calcium oxide content must be increased to more than 35%. Separating the hardened cement paste from the aggregate while reducing the crushing ration of the aggregate during the crushing process is an important means of increasing the calcium oxide content of waste concrete fine powder. Accordingly, this study conducted an experimental study to increase the calcium oxide content of waste concrete fine powder using exfoliation grinding technology. The characteristics of waste concrete fine powder recovered through the exfoliation grinding technology were examined for waste concrete collected from a domestic intermediate processing company, model concrete manufactured in a laboratory, and commercially available cement bricks. As a result of the experiment, it was possible to recover the waste concrete fine powder with a higher CaO content by applying exfoliation grinding technology, compared to the dust collection fine powder that could be recovered through the crushing and grinding process.