تحلیل اقتصادی فرآیند انعقاد الکتریکی در تصفیه پسماند حفاری پایه پلیمری و مقایسه هزینه آن با انعقاد شیمیایی مبتنی بر PAC

The management of polymer-based drilling waste poses significant challenges due to its high organic load, substantial sludge generation, and limited water resources in oil-producing regions, necessitating the adoption of efficient and cost-effective treatment methods. In this study, the combined sedimentation–electrocoagulation (EC) process was evaluated from economic and energy perspectives and compared with the conventional chemical coagulation method using polyaluminum chloride (PAC). The cost–benefit analysis was conducted on the basis of treating one cubic meter of wastewater, using prevailing Iranian prices for the years 2024–2025. The results indicated that the direct treatment cost of EC was approximately 11,760 IRR/m³, whereas that of PAC was about 21,100 IRR/m³. When accounting for the benefits of water recovery (0.8 m³ for EC compared to 0.6 m³ for PAC) and reduced disposal costs, the net treatment cost for EC decreased to approximately –7,040 IRR/m³, representing a net economic saving. In contrast, the PAC process still exhibited a positive net cost of approximately 5,400 IRR/m³. Moreover, the specific energy consumption for COD removal in the scalable EC scenario was calculated to be about 1.77 kWh/kgCOD, while a higher value of 8.85 kWh/kgCOD was observed at the laboratory scale. Overall, the findings demonstrate that electrocoagulation, operating under alkaline conditions and employing low-cost, reusable steel electrodes, represents an economically viable and industrially scalable treatment option and, in many scenarios, outperforms conventional chemical coagulation.