Research on the Transformation of Oyster Shells into a Green, Recyclable, Low Carbon Emission Building Material

Abstract

In response to climate change and sustainable environment, the "circular economy" that reduces energy development and waste reuse is an important carbon reduction strategy in addition to developing green energy. Based on the circular economy theory of local materials and local use, combines quenched blast furnace slag and geopolymer technology to convert waste oysters into building materials bricks for effective utilization. Our goal is to "recycle" oyster shell waste, "reduce" carbon emissions from the manufacturing, and achieve "recycling". Innovative high-pressure bricks that meet local building material standard. The experiment results show that: 1. The ratios of oyster shell and quenched blast furnace slag were 7:3 and 5:5 respectively, made under the pressure of 110kgf/cm². Curing 28 days later, the compressive strength was 27.5MPa and 38.4MPa, respectively. The bending strength was 3.6MPa and the abrasion test was 1.94mm. 2. Crushing the original high-pressure bricks made of oyster shells, added oyster shell powder and quenched blast furnace slag, remade them in a ratio of 7:3. Curing 7 days later, the compressive strength can reach 41.46 and 51.66MPa.3. Each high-pressure brick made of oyster shells will produce 0.206 to 0.219kg CO₂ emissions, which is 49% to 52% fewer carbon emissions than the 0.422kg CO₂ emitted by each high-pressure concrete brick. 4.The remade oyster shell high-pressure reformed bricks will produce 0.295 to 0.304kg CO₂ emissions, which is 28% to 30% lesser carbon emissions than each high-pressure concrete brick. This result can prove that the oyster shell high-pressure bricks can pass Taiwan’s CNS and Green-building materials standard, comply with the circular economy and achieve the goal of net-zero carbon emissions.