Assessment of the Chemical Properties and Resource Utilization Potential of Paprika Plant Residues

The area of hydroponic cultivation in Korea has rapidly expanded in recent years, raising concerns over the management of by-products, such as waste plant residues and spent growing media. Despite the increase in hydroponic cultivation, studies of the treatment and recycling of plant residues and growing media remain limited, necessitating the development of sustainable disposal and utilization methods. This study aims to evaluate the chemical characteristics of paprika plant residues generated after hydroponic cultivation and assess their potential for conversion into solid fuels, thereby proposing sustainable utilization strategies. Plant residues were collected from six farms across the country and analyzed for pesticide residues, heavy metals, inorganic components, and for their solid fuel quality. The analysis revealed that certain pesticide residues exceeded the permissible limits set by domestic and international standards, with zinc (Zn) levels also surpassing the acceptable thresholds in some samples. Conversely, the residues contained high levels of essential inorganic nutrients such as nitrogen (N), calcium (Ca), phosphorus (P), potassium (K), and magnesium (Mg), indicating their potential for use as compost or soil amendments. Although the lower heating value, moisture content, and ash content of the residues did not meet the standard solid fuel quality criteria, the high biomass content suggests that they could be effectively utilized as solid fuel with additional pre-drying treatments. These findings indicate that paprika plant residue, when properly pretreated and managed, can be repurposed using various resource recovery methods, thereby contributing to agricultural waste reduction and the development of sustainable agricultural systems.