應用在固態燃料電池的都市廢棄物連續氣化及燃氣重整研究

Abstract

近年隨著都市廢棄物日漸增加，產生廢棄物處置的問題，最好的方法是將其資源化。因此，都市廢棄物也可以氣化，產生合成燃料，回收再利用這些垃圾的化學能。本研究將三種都市廢棄物氣化，使用碳酸鉀當作催化劑來減少產物中焦油含量，最佳狀態可將交由量降低至13.7 % 。氣化後產生的燃氣需要再經過重整催化，使用Ni-CeO2/γ-Al2O3當作催化劑，進行重整，而得到濃度為51.3 vol% H2、44.8 vol% CO及3.4 vol% CH4的合成氣。合成氣中的雜質硫化氫經由碳酸鈣吸附除硫後，可以將其濃度降至0.04 ppm。另外，研究設計一小型及可攜帶式的連續氣化爐，每小時處理量為300g。此氣化爐使用廢紙，在1.0 L min-1的空氣流量下，產生的氫氣含量達46.9 vol%，且其氫氣濃度隨進料速率及空氣流率增加而減少。最後，使用此合成器當作燃料，供給固態燃料電池，在800oC，氣體當量(φ = 0.4)，電池輸出功率可達269 mW cm-2。

The increasing amount of MSW in recent years raises the problems of sustainable disposal in Taipei cities. For recovering chemical energy, wastes can be served as fuels in gasification processing. In this study, thermal process of three city wastes was conducted and K2CO3 catalyst was used as a catalyst to reduce the amount of tar, which was lowered to 13.7 wt% in MSW. Raw syngas from gasification was then reformed by Ni-CeO2/γ-Al2O3 catalyst to get syngas with optimized quantity of 51.3 vol% H2 and 3.4 vol% CH4. Impurity of H2S generated in waste paper was reduced to 0.04 ppm by adsorption of CaCO3. Continuous gasifier designed with small-scale and portable feature was set up in a processing capability of 300 g h-1. The H2 production of waste paper in the gasifier was 46.9 vol% in air flow rate of 1 L min-1. With a higher waste feeding rate and air flow rate, the H2 content decreased. The syngas with 51.3 vol% H2, 44.8 vol% CO and 3.4 vol% CH4 was used in single cell and the power output was 269 mW cm-2 at 800oC. The gas equivalence ratio φ was ~ 0.19.