就目前焚化系統排氣戴奧辛之控制技術而言，以活性碳噴入技術吸附戴奧辛的方式最被工程界所接受，目前國內外焚化爐多以此技術控制戴奧辛的排放，但採活性碳注入技術(ACI)並無法有效地使氣流中的活性碳與戴奧辛完全接觸，造成PAC 的利用率偏低，操作成本較高。此外，以活性碳吸附方式僅是將煙道氣中之氣相戴奧辛轉移至固相中，可能造成戴奧辛在活性碳表面的生成，進而造成垃圾焚化廠戴奧辛排放量95％以上皆分佈於飛灰及反應灰中，這些含有高濃度之戴奧辛固體廢棄物可能成為未來環境污染問題的隱憂。因此，在研究計畫中，本研究群將開發更有效率的活性碳吸附系統，擬結合流動床式活性碳吸附床(moving bed activated carbon, MBAC) 及活性碳再生系統 (regenerator)，在高溫及缺氧的條件下，將吸附於活性碳表面的戴奧辛予以分解或轉化，接著再將活性碳返送回MBAC 中，真正達到降低戴奧辛對環境之毒害。在第一年的研究規劃中，重點在流動式活性碳吸附床模組設計，主要藉由攝影記錄及計算顆粒體流動速度增進對流場的瞭解，根據量測結果設計適當的檔板長度與傾斜角，以達預期順暢流動效果(mass flow)。第二年的規劃重點在流動式活性碳吸附床去除煙道排氣中戴奧辛類化合物之研究，探討在不同操作參數條件下，如操作溫度、活性碳種類、氣流速率(Superficial Velocity)及活性碳循環速率(Activated Carbon Circulation Rate)，以掌握活性碳對戴奧辛之吸附特性。第三年的規劃重點在活性碳再生系統之戴奧辛減量評估，以掌握戴奧辛的分解特性及最佳操作參數，期望開發更環保、更有效率的新穎戴奧辛排氣控制技術。 To meet the stringent PCDD/F emission standards, municipal waste incinerators worldwide apply different air pollution control devices (APCD) and procedures, leading to different levels of PCDD/F control. Among the methods used, activated carbon injection (ACI) is considered as the simplest one. Nevertheless, some problems exist in controlling PCDD/F emissions from MWIs with ACI. The removal efficiencies of PCDD/F congeners achieved with ACI are not always consistent. ACI technology can reduce flue gas PCDD/F concentrations, but actually increases the total PCDD/F discharge (including those existing in fly ash and flue gas) from MWIs. The presence of activated carbon provides the basic organic material and catalytic surface for PCDD/F formation. The possibility of a homogeneous gas-phase reaction is also being investigated. In addition, previous studies indicates the ACI technology only transfers vapor-phase PCDD/Fs to the reacted ash and would make ash disposal even more complicated. To effectively control the PCDD/F emitted from different facilities, we propose to integrate the moving bed activated carbon (MBAC) and activated carbon regeneration system (ACR) into one PCDD/F control device. The device is designed to destroy the PCDD/F congeners adsorbed in activated carbon in a high-temperature and oxygen-lean condition. After that, the PCDD/F-free activated carbon can be re-discharged into the MBAC for better utilization. In the first year, we focus on designing the MBAC system and evaluating the flow characteristics of activated carbon in MBAC. Based on the video camera and observation of activated carbon pellet flow pattern in MBAC, the optimum length and angle of inclination of deflector in MBAC can be established to make the mass flow smooth in the MBAC. In the second year, we focus on the evaluation of PCDD/F congener removal with the MBAC system established. To examine the adsorbing capacities and characteristic of the activated carbons used in MBAC, the research is motivated to investigate the PCDD/F removal efficiency achieved with temperature variation, different types of activated carbon, superficial velocity and sand circulation rate variation. In the third year, we will estimate and evaluate the PCDD/F reducing rate with the ACR system. The characteristics of PCDD/F removal and optimum operating parameters of the MBAC will be established in this study. 研究期間：9608 ~ 9707
