在工業煉焦過程中，積碳常常附著在煉焦爐之內壁。長時間煉焦作業後，積碳囤積之厚度將造成煉焦爐內推焦作業系統之損壞。文獻上知道透過管子導入空氣之方式燒除壁面之積碳亦是一種高效率之方法。本研究將透過流體力學計算，對煉焦爐作出數值模擬。透過數值計算方法可提供與分析煉焦爐內實際狀況，並探討透過導入空氣式燒除積碳之可行性評估。此物理問題為三維、暫態、當中涉及紊流與化學反應之流場，並進行四個不同燒除作業操作案例之模擬分析，其中三個為不同之噴流流量設定和一個不同之設計噴流位置之案例。結果顯示，於煉焦室內注入空氣確可達到燒除壁面積碳之效果，且以噴流流量較大之案例，其燒除效果較佳。此外，在除碳過程中打開煉焦爐之加料口可由大氣中提供更多之氧氣參與燃燒，並提高燒除積碳之效能。同時監控爐內壁面之溫度，以確保燒炭的過程不至於破壞其壁面。

Carbon Deposits are often occurred inside the industrial coke oven during coking process. Accumulation of carbon deposits may cause a big issue, which seriously influences the coking operation. The carbon is burning off by injecting fresh air through pipes into coke oven which is an efficient way practically operated in industries. The burning off carbon deposition in coke oven performed by Computational Fluid Dynamics (CFD) method has provided an evaluation of the feasibility study. A three dimensional, transient, turbulent reacting flow simulation has performed with three different injecting air flow rate and another kind of injecting configuration. The result shows that injection higher air flow rate would effectively reduce the carbon deposits. In the meantime, the opened charging holes would suck extra oxygen from atmosphere to participate in reactions. In term of coke oven operating limits, the wall temperatures are monitored to prevent over-heating of the adiabatic walls during burn-off process. It is demonstrated that the burn-off method by injecting fresh air is feasible to remove the carbon deposits in coke oven. Due to the number of computational nodes being as huge as about 5×10^7, a result at time of 8.3 s would require 3 months computation time in the present study.

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