AI 中文总结
本文针对H₂-DRI-EAF-MeOH系统容量配置问题，提出基于分式规划的模型，采用ANROI评估投资回报，案例显示其IRR优于ANR基准，离网场景下零碳约束会降低IRR。
AI 中文摘要
集成甲醇合成的氢基直接还原铁-电弧炉系统（H₂-DRI-EAF-MeOH）为零碳钢生产提供了可行路径，但可再生能源（RES）的波动性和间歇性可能导致容量过度配置，而传统的年化成本和平准化成本指标不足以评估投资回报。为解决这些问题，本文开发了一种基于分式规划的H₂-DRI-EAF-MeOH系统最优容量配置模型，将小时产能上限与年产能解耦，作为独立决策变量。理论分析表明，提高小时产能上限可扩大多时段运行可行域，增加RES匹配的理论上限，并提供提高小时产能上限的投资效率条件。随后采用年化投资净回报率（ANROI）表征投资回报，所得混合整数线性分式规划模型用Dinkelbach法求解。案例研究显示，与年化净回报（ANR）基准相比，基于ANROI的配置可获得更高的内部收益率（IRR），并网和离网场景下分别达20.67%和17.08%；当等效年运行小时数从8000降至4000小时，并网场景下IRR从19.68%升至20.67%，离网场景下从12.64%升至17.08%，对应电池储能容量分别减少113.56 MWh和796.31 MWh；离网零碳约束支持CO₂制甲醇，但使系统IRR降至14.99%，表明相关收入不足以抵消额外成本。
英文摘要
A hydrogen-based direct reduced iron-electric arc furnace system integrated with methanol synthesis (H2-DRI-EAF-MeOH) provides a feasible pathway toward zero-carbon steel production. However, the volatility and intermittency of renewable energy sources (RES) may lead to capacity oversizing, while conventional annualized-cost and levelized-cost metrics are insufficient to evaluate investment return. To address these issues, this paper develops a fractional programming-based optimal sizing model for the H2-DRI-EAF-MeOH system. Hourly production rate limits are decoupled from annual production capacities and formulated as independent decision variables. Theoretical analysis demonstrates that increasing hourly production rate limits expands the multi-period operating feasible region, increases the theoretical upper bound on RES matching, and provides an investment-efficiency condition for increasing production rate limits. The annualized net return on investment (ANROI) is then adopted to represent investment return, and the resulting mixed-integer linear fractional programming model is solved using the Dinkelbach method. Case studies show that compared with the annualized net return (ANR) benchmark, the ANROI-based sizing yields higher internal rates of return (IRR), reaching 20.67% and 17.08% under the on-grid and off-grid scenarios, respectively. As the equivalent annual operating hours decrease from 8000 to 4000 h, the IRR increases from 19.68% to 20.67% under the on-grid scenario and from 12.64% to 17.08% under the off-grid scenario, while the corresponding battery storage capacities decrease by 113.56 and 796.31 MWh. The off-grid zero-carbon constraint enables CO2-to-MeOH conversion but reduces the system IRR to 14.99%, indicating that the resulting revenues are insufficient to offset the additional costs.
