選擇性觸媒還原法脫硝技術應用於台灣地區經濟可行性之研究

Abstract

選擇性觸媒還原法是目前處理氮氧化物最有效率之方法，且幾乎無二次公害形成。但應用SCR法控制氮氧化物有成本較高之考量，使得欲採行之廠家望之卻步。本研究之目的即在探討SCR法之成本與空污費費率間之互動關係，以瞭解在設定之空污費費率下，SCR法之應用性，及其可能之NOx減量效果。 本研究藉由收集目前國內實場運作SCR之各項相關成本概況，建立一成本迴歸經驗公式，利用線性規劃之觀念，以新竹縣為案例討論區域，分別探討於個別管制與總量管制下，應用SCR進行氮氧化物削減之經濟可行性，並加入敏感度分析，探討所需耗材價格變動下對SCR設備成本之影響。研究結果顯示，成本迴歸公式經代回原收集資料數據驗證後，具有一定之可信度，可供日後欲設立SCR系統之成本推估參考；若與總量管制規劃結合來進行氮氧化物削減，將可提高SCR之應用比率。而空污費費率訂於12, 000NTD/ton基準，且不考慮工廠之最小投資報酬率時，則可能運用SCR技術來削減870∼1300ton/yr之NOx排放量，此約相當於20∼30%之研究區域內NOx排。在敏感度分析方面，觸媒之使用壽命是影響SCR設備成本支出之重要因子，原設計更換週期為兩年之觸媒，在良好操作條件與定期保養下，若可延長至八年之更換週期，則成本節省之差距最高可達50%。

The Selective Catalytic Reduction (SCR) is one of the best technologies for NOx removals. However, it is usually considered as too expensive to be adopted by many industrial sources. This study focuses on an economic evaluation of the SCR. The feasibility of the SCR as applied in Taiwan is investigated by comparing its marginal cost with the air pollution fee, both under individual controls and the bubble policy strategy. This study establishes a cost regression function for the SCR technology based on actual plant application data in Taiwan, and employs a linear programming model to study the economic feas ibility of the SCR under the bubble policy strategy. The Hsinchu county is the case study area, and the effects of catalysts and NH3 injection costs are evaluated in by a sensitivity analysis. The results show that as applied under the bubble policy regulation, the SCR is more feasible than the traditional command and control regulation of individual controls. When the air pollution fee is set at 12, 000NTD/ton, the SCR technology may remove 870∼1300 ton/yr of NOx emission for the case of neglecting the minimum rate of return. This equals to 20∼30% of total NOx emission from the study area. If the useful life of catalysts catalysts can be extended from 2 to 8 years, the SCR cost can be reduced to as much as 50% of its original price.