PERFORMANCE OF WASTEWATER TREATMENT PLANT (WWTP) TO TREAT PHOSPHATE (PO4) OF PT PETROKIMIA IN GRESIK CITY 2025

Abstract

Background: Wastewater management in the fertilizer industry, particularly at PT Petrokimia Gresik, poses considerable challenges due to the presence of complex chemical pollutants. By 2024, secondary data shows a sharp increase in the concentration of phosphate (PO₄) pollutants by 147.7%. These figures raise concerns about the effectiveness of the existing Wastewater Treatment Plant (WWTP) system. Objective: This study aims to evaluate the performance of the Wastewater Treatment Plant at PT Petrokimia Gresik in 2025, specifically focusing on phosphate (PO₄) removal efficiency across different treatment units. Methods: This study used a quantitative research approach using observation, documentation, and grab sampling techniques in accordance with SNI 8990:2021. The analysis focused on the main water quality parameter, PO₄ from the PT Petrokimia Gresik WWTP. Data were evaluated based on removal efficiency, residence time, and potential reuse of wastewater. Results: The findings showed that the phosphate removal efficiency was low, indicating inefficiency in the treatment process. Although the residence time remains within acceptable limits, it has not led to a significant reduction in pollutant levels. Conclusion: The current WWTP system has not been effective in meeting quality standards, especially regarding PO₄. Comprehensive reutilization of effluent is ongoing, but improvements in design and treatment technology are needed to enhance performance.