Cleaner production of high-quality manufactured sand and ecological utilization of recycled stone powder in concrete

This paper reports a case study on cleaner production of digital control manufactured sand (DMS) and ecological utilization of recycled SP (stone powder) in Hechi-Baise Expressway Project. The novel production system can not only produce high-quality manufactured sand, but also recycle waste stone powder and reduce environmental pollution. Compared with common manufactured sand, the digital control manufactured sand has more reasonable gradation, modified particle shape and regulable stone powder content, which will significantly simplify the ecological application of DMS. The performance of fine aggregate type and stone powder content under several engineering mix proportions is evaluated. The results show that compared with manufactured sand (MS) concrete, the working performance of concrete with DMS is increased by 16.19% on average, and the strength is increased by 7.1% on average, and it has excellent resistance to chloride ion penetration., The application of DMS also reduce the cement and supplementary cementitious materials content of concrete. Recycled SP is comprehensively used in the digital control cleaner production of manufactured sand. The zero discharge of solid waste i.e., waste stone, rubble, dust, and slurry is realized, therefore remarkable economic and ecological benefits are achieved.