Chiang Mai Journal of Science

     This study aims to investigate the utilization of lightweight expanded clay aggregate (LECA) produced by combining clay with industrial waste as a planting material for soil moisture retenti on. Lightweight expanded clay aggregate is a growing media material composed of clay pellets subjected to high temperatures. This substance is created by combining clay with pore-forming elements, such as pulverized waste from the automotive sector. The compressed waste particles comprise polymer fiber, glass shards, lubricating oil, and various other components. This waste is imported from overseas to serve as a cost-effective fuel source for energy production. In order to further develop its potential applications, it is combined with clay to investigate the feasibility of developing a novel substrate to replace materials like perlite and vermiculite that are currently in use. The experiment entails molding a mixture of clay and waste fragments in different proportions and subjecting them to fire at temperatures ranging from 700 to 800 degrees Celsius. The research results indicated that 30% of clay with 70% of industrial waste is the most suitable combination and slip casting parameters. Examining the physical and chemical characteristics of the LECA reveals that they possess pores capable of efficiently retaining water and moisture. The bulk density was 1.05 g/cm³, the apparent porosity was 53.21%, and the water absorpti on was 50.60%, which indicates their high capacity to absorb water. The pH of LECA suited for plant growth commonly lies within the range of 6.5 to 8, which is close to the suitable pH value. The experiment has yielded a novel, highly permeable, lightweight expanded clay aggregate that efficiently retains moisture in the topsoil and is available in many forms. Furthermore, using industrial waste and employing low-forming temperatures enable this innovation to be ecologically sustainable.