廃水処理の脱炭素化：太陽光駆動型オンサイト酸化剤製造の比較ライフサイクル評価

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

🔬研究者:LCA手法と電解酸化の性能データを組み合わせた分散型脱炭素技術の評価枠組みを提供する。

🏢実務担当者:遠隔地・分散型拠点での薬品調達コストとScope 3排出を同時に削減する選択肢として検討可能。

🏛政策担当者:産業廃水処理の脱炭素化支援策や分散型インフラ投資の根拠として参照できる。

Produced water and industrial wastewater treatment systems represent a significant yet often under-examined source of indirect greenhouse gas emissions within industrial operations. While chemical oxidation remains one of the most effective and widely adopted treatment mechanisms for complex wastewater streams, the environmental impacts associated with the upstream production and logistics of chemical oxidants are substantial. Conventional oxidants are typically manufactured in centralized facilities using fossil-fuel-derived electricity and thermal energy, followed by energy-intensive packaging, long-distance transportation, on-site storage, and controlled dosing. These upstream and auxiliary processes contribute materially to cumulative energy demand, scope-3 emissions, and operational risk, particularly for remote and decentralized treatment installations. As global decarbonization targets intensify across industrial sectors, the continued reliance on conventional oxidant supply chains is increasingly misaligned with emerging sustainability objectives. This study evaluates a solar-powered electrochemical system designed to locally manufacture oxidants on demand using low-voltage ion-exchange reactors. By generating oxidizing species directly at the point of use, the system eliminates the need for externally supplied chemicals and significantly reduces dependence on fossil-fuel-based energy inputs. The primary objective of this work is to assess the environmental and operational performance of this renewable-powered, decentralized treatment approach as a low-carbon alternative for produced water and industrial wastewater treatment. A comparative Life Cycle Assessment (LCA) framework is applied to quantify differences in environmental performance between conventional oxidant-based treatment pathways and localized in-situ oxidant generation. This study intentionally focuses on physical environmental performance in accordance with ISO 14040/44 using a functional unit of 1 m3 of treated wastewater; monetary valuation of impacts will be addressed in subsequent ELCC-focused work. Scenario 1 represents conventional oxidant manufacturing and delivery, encompassing centralized chemical production, packaging, transportation, on-site storage, and dosing. Scenario 2 represents localized, solar-powered in-situ oxidant generation, in which oxidants are produced electrochemically using photovoltaic electricity, thereby eliminating most fossil-energy-dependent supply-chain stages. Foreground process data were obtained from laboratory-scale testing of produced water and industrial wastewater, evaluating key performance indicators including chemical oxygen demand (COD), biochemical oxygen demand (BOD), total organic carbon (TOC), ammonia nitrogen (NH3-N), total suspended solids (TSS), and hydrocarbon removal. Background inventory data were derived from established life-cycle databases representative of industrial chemical production and energy systems. Environmental indicators evaluated include global warming potential, cumulative energy demand, supply-chain emissions, and qualitative chemical-handling risk. The results indicate that localized solar-powered oxidant generation achieves reductions in global warming potential ranging from approximately 65% to 85% relative to conventional oxidant supply chains. Most avoided emissions are attributable to the elimination of centralized chemical manufacturing, long-distance transportation, and hazardous chemical storage. Laboratory testing confirmed that the localized electrochemical system maintains high treatment efficiency, achieving 88–99% reductions in COD, BOD, and TOC across multiple wastewater matrices. Oxidation reactions converted dissolved organic contaminants into particulate or settleable forms that were effectively removed using conventional filtration and polishing processes. Overall, the findings demonstrate that renewable-powered localized oxidant manufacturing provides a technically robust, operationally flexible, and environmentally superior pathway for industrial and oilfield wastewater treatment, particularly in remote or infrastructure-constrained settings.

• semanticscholar https://doi.org/10.2118/232318-msfirst seen 2026-10-02 05:41:38