Reusing and recycling treated wastewater is a sustainable approach to meet the growing demand for clean water, ensuring its availability for both current and future generations. Wastewater can be treated in such advanced ways that it can be used for industrial operations, recharging groundwater, irrigation of fields, or even manufacturing drinkable water. This strategy meets growing water demand in water-scarce areas while protecting natural ecosystems. Treated wastewater is both a resource and a challenge. Though it may be nutrient-rich and can increase agricultural output while showing resource reuse and environmental conservation, high treatment costs, public acceptance, and contamination hazards limit its use. Proper treatment can reduce these hazards, safeguarding human health and the environment while enhancing its benefits, including a stable water supply, nutrient-rich irrigation, higher crop yields, economic development, and community resilience. On the one hand, inadequate treatment may lead to soil salinization, environmental degradation, and hazardous foods. Examining the dual benefits and risks of using treated wastewater for agricultural irrigation, this paper investigates the complexities of its use as a valuable resource and as a potential hazard. Modern treatment technologies are needed to address these difficulties and to ensure safe and sustainable use. If properly handled, treated wastewater reuse has enormous potential for reducing water scarcity and expanding sustainable agriculture as well as global food security.

This study evaluates the techno-economic and environmental feasibility of hydrogen (H₂) production via co-gasification of woody biomass and polyethylene (PE) plastic waste, with and without carbon capture and storage (CCS), using an integrated modeling framework. Four scenarios were analyzed: (1) biomass gasification without CCS, (2) biomass with CCS, (3) co-gasification (90:10 biomass:PE) without CCS, and (4) co-gasification with CCS. Process simulations were conducted in Aspen Plus V12.1, techno-economic analysis (TEA) via NREL’s H₂A model, and cradle-to-gate life cycle assessment (LCA) in OpenLCA with TRACI 2.1 and the Cumulative Energy Demand (CED) methods. The plant processes 1500 dry ton/day feedstock, yielding ~136–140 tons/day pure H₂. TEA results show co-gasification without CCS achieves the lowest levelized cost of H₂ (LCOH) at 2.18 USD/kg, 7% below biomass-only (2.34 USD/kg), due to reduced feedstock demand and improved efficiency. CCS increases LCOH by 30–36% (2.98–3.18 USD/kg), but 70 USD/t CO₂ credits reduce it to 1.74–1.81 USD/kg, competitive with gray H₂. Sensitivity and Monte Carlo analyses highlight capacity factor and feedstock as key drivers, with co-gasification narrowing uncertainties. LCA reveals co-gasification lowers most impacts by 5–10%, while CCS enables net-negative GWP (−12.3 to −14.7 kg CO₂ eq/kg H₂) but raises CED by 15%. Scenario 4 balances economic viability and climate mitigation, supporting circular economy principles through waste valorization. Findings affirm co-gasification with CCS as a promising pathway for low-carbon H₂, with policy incentives critical for deployment. Future optimizations, like higher PE ratios, could further reduce costs below 2 USD/kg, advancing net-zero transitions.