面對氣候變遷與能源短缺挑戰，各國積極推動能源轉型與廢棄物資源化政策。都市汙泥與廢塑膠為目前最具處理困難度之高污染有機廢棄物，其裂解產物（生質油、固態殘餘物）具備高熱值與再利用潛力，有望透過與傳統燃料共燒方式提升能源回收效率，並減輕環境負擔。本研究以Aspen Plus中的 RGibbs最小自由能平衡模型為工具，模擬裂解產物分別與粉煤/重油之共燒行為，系統性評估不同燃料配比與操作參數（氧氣濃度、煙氣再循環比）對燃燒溫度、污染物排放與蒸汽渦輪功率之影響，並篩選具可行性與符合法規性之最適操作條件。
模擬設計分別針對液態燃料（生質油/重油）與固態燃料（固態殘餘物/粉煤）系統進行分析。結果顯示，燃料組成與操作參數對性能具顯著影響：液態燃料系統中，第B組於25% O2與45% RFG條件下達成284.51 kW輸出與NOx 排放濃度467.77 ppm@6%O2，具高效燃燒潛力；若採75% A組生質油 與HFO混摻則可兼顧256.42 kW輸出與較低 NOx（462.43 ppm@6%O2），適合需兼顧排放與操作彈性者。固態燃料系統則於21% O2、RFG 30%、固態殘餘物混摻20%下，各組均達250 kW以上功率，NOx控制在743.27～806.92  ppm@6%O2，惟SO2排放超過法規，須搭配脫硫裝置。最大功率條件下，第A組可達304.26 kW，展現最佳效能但亦伴隨最高排放，顯示效率與環保間仍存在權衡。

In response to the challenges of climate change and energy shortages, many countries are actively promoting energy transition and waste-to-resource policies. Municipal sewage sludge and waste plastics are among the most difficult high-pollution organic wastes to manage. Their pyrolysis products—bio-oil and solid residue—exhibit relatively high heating values and promising reuse potential. Co-combustion these products with conventional fuels offers a viable pathway to enhance energy recovery while mitigating environmental burdens. In this study, an Aspen Plus RGibbs (minimum Gibbs free energy) equilibrium model was employed to simulate the co-combustion behavior of pyrolysis products with pulverized coal and heavy fuel oil (HFO). The effects of fuel blending ratio and key operating parameters (oxygen concentration and flue-gas recirculation ratio, RFG) on combustion temperature, pollutant emissions, and steam-turbine power output were systematically evaluated, with the aim of identifying feasible operating windows that comply with regulatory constraints.
Two sets of simulation cases were designed for liquid-fuel systems (bio-oil/HFO) and solid-fuel systems (solid char residue/pulverized coal), respectively. The results indicate that both fuel composition and operating conditions significantly affect system performance. For the liquid-fuel system, Case B achieved a power output of 284.51 kW and NOx emissions of 467.77 ppm at 6% O2 under 25% O2 and 45% RFG, demonstrating high efficiency potential. Alternatively, a 70% Case A boo-oil co-firing condition provided a balanced performance with 256.42 kW output and lower NOx (462.43 ppm@6%O2), which may be more suitable when both emission control and operational flexibility are required. For the solid-fuel system, at 21% O2 and 30% RFG with 20% solid char residue blending, all cases produced more than 250 kW, with NOx maintained within 743.27～806.92  ppm@6%O2. However, S O2 emissions exceeded regulatory limits, indicating that an additional desulfurization unit is necessary for compliance. Under the maximum-power condition, Case A reached 304.26  kW, representing the best performance but also the highest emissions, highlighting a clear trade-off between efficiency and environmental impact.

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