A Case Study on the Treatment of phenolic wastewater from an inland natural gas field using a trickling biofilter

Fazaelipoor, Mohammad Hassan; Keshtvarz, Mohammad Reza

doi:10.22104/mmb.2026.8196.1201

A Case Study on the Treatment of phenolic wastewater from an inland natural gas field using a trickling biofilter

Articles in Press

Document Type : Case Study

Authors

Mohammad Hassan Fazaelipoor ¹

Mohammad Reza Keshtvarz ²

¹ Department of Chemical and polymer Engineering, Faculty of Engineering, Yazd University, Yazd, Iran

² HSE Department, South Zagros Oil and Gas Production Company

10.22104/mmb.2026.8196.1201

Abstract

Phenolic wastewater generated during natural gas recovery poses serious environmental challenges, requiring efficient and economical treatment solutions. This work documents a field case study on the performance of a lava rock-packed trickling biofilter for treating phenolic wastewater from a natural gas field. The system was seeded with municipal activated sludge and acclimated for one month before operation. Its performance was evaluated at varying empty bed residence times (EBRTs) and influent pH values, with a focus on chemical oxygen demand (COD) and phenol removal. Results showed that increasing EBRT improved treatment efficiency. For COD removal, efficiency reached up to 88% (554 to 65 mg/L) at 19 min EBRT. For phenol removal (tested in a separate run), removal exceeded 98% (9.5 to 0.146 mg/L) at the longest EBRT tested, 14.4 min. COD profiles along the filter depth indicated active biodegradation throughout the trickling biofilter, while performance remained stable across a broad pH range (2.5–9.1), with COD and phenol removal efficiencies of 72–88% and 84–92%, respectively. These findings highlight the robustness of trickling biofilters in handling variable wastewater conditions without the need for external nutrient supplementation. Overall, this study supports the view that trickling biofilters can be a cost-effective, low-maintenance, and sustainable option for treating phenolic wastewater from natural gas recovery operations.

Keywords

Trickling biofilter

phenol

Chemical Oxygen Demand

phenolic wastewater

Subjects