ISSN: 2167-0587
Seounghwa Choi
Background: The industrial development has increased and diversified refractory organic compounds in wastewater. The Ministry of Environment of South Korea is reviewing the introduction of a new organic pollutant index and discussing the conversion of the existing indices to the total organic carbon (TOC). Thus, specific research on this issue is required. Methodology: The characteristics of existing organic pollutant indices (BOD, CODMn, and CODCr) and TOC by industry were examined for 210 samples of waste effluents generated in Busan in 2017 and 2018. Findings: The TOC and COD were the highest in the chemical materials and products manufacturing industry, followed by the food production industry and waste disposal industry. The BOD was the highest in the food production industry, followed by electronic parts/semiconductors manufacturing industry, waste disposal industry, and chemical product manufacturing industry. The ratios of organic oxidation of CODMn and CODCr to TOC were 51.9 % and 88.7 %, respectively. This confirms that the existing organic pollutant index COD is underestimating the amount of refractory organic compounds. For the correlations between TOC and the existing organic pollutant indices (CODMn, CODCr, BOD5), CODMn (r=0.970) showed the highest correlation, followed by CODCr (r=0.956) and BOD5(r=0.812). Conclusion & Significance: TOC and COD showed a particularly high correlation. This suggests that TOC is a valid organic pollutant index for the water quality of waste effluents that can replace COD in the future. In conclusion, the introduction of TOC with a high organic matter oxidation rate is required to evaluate various refractory organic compounds contained in wastewater. This study examined the applicability of a new organic pollutant index (TOC) for water quality management of industrial wastewater discharged to public waters and will provide important data for the introduction of related standards.