Development and simulation of deactivation process of favipiravir in a pharmaceutical wastewater system

Favipiravir (FPV) has been widely used to treat COVID-19 patients in many countries, including Thailand, owing to its potent antiviral activity. Consequently, the wastewater discharged from the formulation process contains a significant amount of active pharmaceutical ingredients that could be harmful to humans and animals if released into the environment without proper treatment. Therefore, this study aimed to develop a deactivation process for FPV present in wastewater using SuperPro Designer Version 10 program. The deactivation processes were classified as two cases: case I (base case) using sodium hypochlorite (NaOCl) at 10% v/v and case II using ozone at 16 g/L. Each case was separated into a subcase A, representing the lack of a filtration unit, and subcase B, representing the use of a filtration unit. The operations used in this study can be characterized as the deactivation unit, neutralization unit, and filtration unit, selected from the equipment available at CRPMF. The simulation results showed that case IIA (with ozone and without filtration) provided the greatest deactivation of FPV per year (65,661 kg/year) but required higher annual investment and operating costs. Meanwhile, case IA (with NaOCl and without filtration) demonstrated an FPV deactivation of 49,243 kg per year, with a cost seven times lower than that of case IIA. In summary, the simulation and cost analysis information were provided to assist CRPMF and other pharmaceutical manufacturers in selecting the scenario that is best suited for the annual capacity of antiviral drug formulation.