實廠規模沉積物微生物燃料電池應用於豬場廢水處理之性能與可行性評估

Abstract

本研究之目的為評估實廠規模沉積物微生物燃料電池（SMFC）安裝於豬場廢水處理設施之可行性。試驗地點位於台灣宜蘭縣一處飼養規模約1,500頭之商業豬場，SMFC依序安裝於第8號及第3號厭氧消化槽。20片石墨烯塗層不鏽鋼纖維氈陽極沉入消化槽廢水中，六個聚氯乙烯陰極安裝於厭氧消化槽液面，內置備長炭，以無紡布陶瓷隔離膜作為離子傳輸介面，並以聚乙烯醇海綿及聚乙烯網加以保護，並注入1:1稀釋海水作為陰極液。系統連接一顆3000F超級電容器進行電壓與電流之連續監測。試驗結果顯示，第8號厭氧消化槽之超級電容器電壓於44天內從0.200 V穩定上升至0.803 V，最大儲能約967 J；第3號厭氧消化槽經陰極修正後，電壓於28天內從0.336V穩定上升至0.565V。兩座厭氧消化槽在穩定運行期間之平均每小時充電速率相近，分別為0.000746V/h及0.000747V/h，顯示系統性能具良好重現性。廢水水質監測結果顯示，兩座厭氧消化槽之有機基質充足，化學需氧量分別為541mg/L及266mg/L，具備支持生物電化學反應之條件。本研究證實，實廠規模沉積物微生物燃料電池可整合安裝於現有豬場厭氧消化槽，並在實際場域條件下維持穩定之充電性能，具推廣應用之可行性。

The objective of this study was to assess the feasibility of installing a full-scale sediment microbial fuel cell (SMFC) in a piggery wastewater treatment facility. The study site was a commercial pig farm with approximately 1,500 heads in Yilan County, Taiwan. The SMFC was installed concurrently in anaerobic digester#8 and anaerobic digester#3, with AD#3 subsequently corrected and restarted following early operational disturbances. Twenty graphene-coated stainless-steel fibre felt anodes were submerged in the digester wastewater, and six polyvinyl chloride (PVC) cathodic units were mounted at the anaerobic digester surface. Each cathodic unit contained a binchotan charcoal cathode protected by a non-woven ceramic separator (forming the ionic-transport interface with the wastewater), a polyvinyl alcohol (PVA) sponge, and a polyethylene (PE) net (providing physical protection), and was filled with diluted seawater catholyte at a ratio of 1:1. The system was connected to a 3000 F supercapacitor for continuous voltage and current monitoring. Experimental results showed that the supercapacitor voltage at anaerobic digester#8 increased steadily from 0.200 V to 0.803 V over 44 days, with a maximum stored energy of approximately 967 J. At anaerobic digester#3, following cathodic unit correction, the voltage increased steadily from 0.336 V to 0.565 V over 28 days. The mean hourly charging rates during stable operation were similar between the two anaerobic digesters, at 0.000746 V/h and 0.000747 V/h, respectively, indicating reproducible system performance. Wastewater quality monitoring showed that organic substrate was sufficient in both digesters throughout the study period, with chemical oxygen demand (COD) of 541 mg/L and 266 mg/L, respectively, providing conditions suitable for bioelectrochemical activity. Results demonstrated that a full-scale SMFC can be integrated into existing piggery anaerobic digesters and maintain stable charging performance under real field conditions, and the system is feasible to be applied and extended to other piggery wastewater treatment facilities.