A study on feasibility of cement clinker manufacture using oyster shell as lime- stone substitute

Abstract

Since the development of shellfish-farming, oyster shells have caused environmental problems along the coast because they are not recycled enough. Previous papers studied recycling oyster shells in construction materials, but they only focused on replacing fine aggregate. This study focuses on the use of oyster shells to replace limestone in manufacturing Portland cement clinker, in order to use a waste material, shells, to make the manufacturing process more sustainable than current cement production methods. The performance of oyster shell cement (OSC) was compared with ordinary Portland cement (OPC) using X-ray powder diffraction, and its structures were identified by Rietveld quantitative phase analysis. The OSC was compared with specimens manufactured with limestone in same conditions (LPC). Cement paste of OPC, OSC and LPC were measured at 1,3, and 7 days to compare strength development. The compressive strength of OPC and OSC developed equivalently over the long-term. The results show that Portland cement clinker can be manufactured using oyster shells, replacing 100% of the limestone. Through this series of analyses, the overall properties of OSC were found to be similar to OPC