Mineral carbonation using alkaline waste and byproducts to reduce CO 2 emissions in Taiwan

Climate change induced partly by emissions of carbon dioxide (CO 2 ) is an urgent issue worldwide, calling for advanced methods of carbon sequestration. Since CO 2 -emitting industries often generate alkaline waste, sequestrating CO 2 by mineral carbonation of alkaline waste is promising both for carbon capture and utilization, and for preventing waste disposal. Here we review the principles of mineral carbonation and we discuss mineral carbonation of alkaline waste and byproducts in Taiwan. We focus on wastes such as iron and steel slag, cement and concrete waste, incineration ash, coal combustion ash, and paper waste. We evaluate the CO 2 reduction potential to reveal promising materials and industries. We found that 4.2 Mt CO 2 can be directly sequestered annually. Moreover, the use of alternative materials in the cement and concrete industries can indirectly facilitate CO 2 sequestration.