본 연구는 시멘트 산업의 대체연료(폐합성수지 등) 사용량 증대에 따라 이를 활용한 탄소배출 저감 및 시멘트/콘크리트 제조 적용 기술 및 방안에 대해 검토하고자 했으며, 향후 시멘트 산업의 탄소중립 실현을 위한 기초 자료로써 활용하고자 한다. 시멘트 제조 에 있어 폐합성수지 사용은 경제적 장점과 높은 발열량으로 인해 연료로서의 가치가 높은 것으로 나타났으며, 열경화성 수지는 부가가 치가 높은 저탄소 시멘트 복합체의 비반응성 골재로 작용할 수 있는 것으로 확인되었으며, 감마선 조사는 다양한 폐플라스틱의 성능 평가에 적용되는 것으로 확인되었다.

This paper presents the actual recycling rates and recycling processes of waste plastic recycling facilities using material flow analysis. Determination of actual recycling rates through the processes of waste plastics is a very important subject not only from the point of plastic recycling efficiency energy conversion but also from the perspective of the recycling technology level. In this study, the recycling processes and recycling rates of waste plastic recycling facilities were evaluated by the MFA analysis based on 14 site visits and 25 questionnaires. The MFA methodology based on mass balance approach applied to identify the inputs and outputs of recyclable plastic materials in the recycling processes at recycling facilities. It is necessary to determine the composition and flows of the input materials to be recycled in a recycling facility. A complete understanding of the waste flows in the processes along with the site visit and data surveys for the recycling facilities was required to develop a material flow for the processes and determine the actual recycling rate. The results show that the average actual recycling rates for the recycling facilities by the site visit and the questionnaire was found to be approximately 87.5 ± 7.1% and 84.3 ± 14.5%, respectively. The recycling rates depended upon several factors including the quality of incoming waste plastics, the type and operating conditions of recycling processes, and the type of final products. According to the national statistics, the recycling rate of waste plastics was about 53.7%, while the actual recycling rate at national level was estimated to be approximately 45.1% by considering the recycling performance evaluated as well as the type of recycling process applied. The results of MFA for the recycling processes served as a tool to evaluate the performance of recycling efficiency with regard to the composition of the products during recycling. They may also support the development of the strategy of improvement of recycling processes to maximize resource recovery out of the waste plastic materials.