Sustainable Conversion of Produced Water into Biohydrogen and Biochar for Low-Carbon Oilfield Operations

Unofficial AI-generated summary based on the public title and abstract. Not an official translation.

🔬研究者:Novel process for high-salinity produced water with biochar integration; techno-economic data for similar systems.

🏢実務担当者:Potential application for oilfield wastewater treatment and hydrogen production; economic feasibility data for decision-making.

🏛政策担当者:Insights into circular economy and CCUS policies for oil and gas sector; supports national resource efficiency goals.

Abstract This study is intended to illustrate an environmentally friendly and cost-effective process of converting produced water to biohydrogen by means of sequential dark and photo-fermentation. In addition, this project will identify optimal operating conditions to increase the production of hydrogen; develop biochar from excess sludge to sequester carbon dioxide; and assess the suitability of the treated water for agricultural purposes. This project is a step towards achieving national objectives of increasing the efficiency of our use of natural resources and promoting long-term reductions in greenhouse gas emissions. The technique entails developing a sequence of dark and photo-fermentation in lab-scale bioreactors with the petroleum produced water. Inoculum will be supplied by mixed bacterial populations obtained from the microbial treatment of wastewater. The key factors influencing the bioreactor system (pH, temperature, organic loading rate, hydraulic retention time and salinity) are to be optimized. Biochar is to be produced through the pyrolysis of excess sludge to provide additional carbon dioxide fixation and improve fermentation processes. Performance of the bioreactor system and feasibility of large-scale implementation will be assessed utilizing techniques such as techno-economic evaluation. The preliminary economic evaluation of this proposed project showed an approximate payback time of 2 to 3.5 years with a net income (profit) of approximately $13,500 per year for a 100 m3/d capacity treatment plant. An estimated 80% COD removal was predicted for the integrated system along with a predicted hydrogen yield of 0.4 L H2/gCOD. The revenue generated by the project included; revenue generated by biohydrogen production in the produced water at a rate of $0.34/m3, biochar synthesis at a rate of $0.07/m3 and the environmental benefit of removing pollutants at a rate of $0.24/m3. The water will be treated to meet agricultural irrigation standards. The project will also show that sequential dark photo-fermentation of produced water can be economically viable and contribute to both waste minimization and renewable energy production, while promoting circular economy principles. The project will address all three major components of sustainability simultaneously as it treats industrial wastewater, produces clean energy, generates value added product and provides water for agriculture. This is the first comprehensive study that was conducted in Oman to convert high-saline produced water to bio-hydrogen using sequential dark and photo-fermentation with the support of biochar. This study has a novel contribution including optimizing parameters for bio-hydrogen production for high saline (approximately 100 g/L) produced waters and integrating biochar derived from waste sludges to enhance CO2 sequestration and fermentative performance while promoting a closed-loop zero-waste operation for oil field activities

• openalex https://doi.org/10.2118/232674-msfirst seen 2026-05-19 04:56:48 · last seen 2026-05-20 05:07:23