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年度	105	專案性質	實驗性質
專案類別	研究專案	研究主題	整治
申請機構	國立高雄海洋科技大學	申請系所	海洋環境工程系
專案主持人	林啟燦	職等/職稱	教授
專案中文名稱	以濕處理及廚餘淨化受戴奧辛污染之土壤
中文關鍵字	濕處理,廚餘,戴奧辛,土壤,整治
專案英文名稱	Clean up dioxin from contaminated soil by wet treatment and fermentation of food waste .
英文關鍵字	Wet treatment,Food waste,Dioxin,Soil,Remediation
執行金額	799,999元
執行期間	2015/11/17 至 2016/11/16
計畫中文摘要	本研究係導入綠色及可持續性整治(Green and Sustainable Remediation, GSR)，採取以濕處理液洗及堆肥之非熱處理整治技術，處理受戴奧辛污土，更符合環境友善綠色整治，並減少空污、水污、廢棄物等二次污染環境足跡，且更經濟低廉以使整治得以持續順利進行。期能將土壤戴奧辛濃度處理至符合法規標準1000 ng I-TEQ/Kg以下，洗土成本低於每公噸污土6000元。 本研究之污染土壤，濕篩採取粒徑0.105~0.250公厘之砂質土壤，使用厭氧液肥、水產生漿、及甘蔗酒三種配方，進行洗土試驗，以評估清洗戴奧辛污土潛勢，另外利用好氧堆肥試驗將含戴奧辛污土降至法規標準。 洗土試驗為戴奧辛污土與上述三類洗土配方皆以1：2.5之重量比（土壤約200公克，萃取液約500公克）混合，攝氏30度，40kHz超音波震盪器。本研究洗土結果顯示，水產物生漿其戴奧辛濃度由未萃取前22,080 ng-TEQ/Kg，水洗後結果為1,298 ng-TEQ/Kg，去除效率為94.1%，接近法規標準1,000 ng-TEQ/Kg；厭氧液肥水洗後其濃度為2,961 ng-TEQ/Kg，去除率為87%；最後甘蔗酒水洗後其去除率為80%。此外，本團隊藉由上述之結果，選擇兩種去除效率較佳之溶劑(厭氧液肥及水產物生漿)，亦試驗高濃度之土壤，其戴奧辛濃度介於110,000至130,000 ng-TEQ/Kg。其中，厭氧液肥洗土後，其濃度由113,565 ng-TEQ/Kg降至殘餘為4,841 ng-TEQ/Kg，去除率為95.74%；水產物生漿洗土後其濃度由134,709 ng-TEQ/Kg降至6,237 ng-TEQ/Kg，去除率為95.37%。 本團隊之好氧堆肥實驗，以負壓箱作為反應器進行好氧堆肥實驗，將戴奧辛污土與廚餘以濕重比為1：3，經充分混拌後，總重5.6公斤。該混合物之戴奧辛初始濃度為2,491 ng-TEQ/kg，歷時63天反應後，其殘留濃度為751 ng-TEQ/kg，去除率為69.9%，且達到土壤污染管制標準1,000 ng-TEQ/kg以下。因此，本團隊藉由上述之結果，嘗試對於只經濕式篩分但未經厭氧液肥或水產物生漿或甘蔗酒等搓洗過後之土壤，進行兩批次好氧堆肥反應器實驗，充分混拌戴奧辛污土與廚餘（濕重比3：7，廚餘成分以生魚肉為主），單組總重80公斤，該堆肥混合物戴奧辛初始濃度各別為7,462及6,048 ng-TEQ/kg，經42與47天反應後，其殘留濃度各為1,916及1,604 ng-TEQ/kg，去除率為74.3%及73.5%，最終殘餘濃度亦近於土壤污染管制標準值。 由此三批次之好氧堆肥實驗結果顯示出對於戴奧辛降解均為有效，且負壓箱與反應器之戴奧辛降解趨勢為吻合。本計畫提出含有戴奧辛污染土壤解除法規管制標準之最佳路徑，為將污土先經由洗劑搓洗將戴奧辛濃度降至5,000至7,000 ng-TEQ/Kg後，再由好氧堆肥處理，亦將殘留餘土壤中戴奧辛濃度降解至本計畫之目標值。
計畫英文摘要	Green and sustainable remediation (GSR) is commonly recognized in the recent years. Going for GSR, air, water, waste, energy and ecological impacts are emphasized to reduce secondary pollutions and to minimize environmental footprints. In this research, we are aiming to explore both technical and economic feasibility of soil washing and composting to treat Dioxin contaminated soils in order to compensate current thermal desorption and thermal destruction treatment in the aspect of reducing energy consumption and CO2 emission. Moreover, the treated soil must comply with the 1000 ng I-TEQ/Kg control criteria. Competitive and affordable treatment cost is expected for less than NTD$6000/ton. A pretreatment, namely soil screening/sieving, is conducted for obtaining a glance at particle distribution of the soil. The result shows that fine sand is the major component of the soil, accounting for more than 60% of the total mass. Both fish broth and anaerobic compost tea were chosen as probe of greener washing fluids. A combined treatment of ultrasonification and mechanical double-blade agitation is employed, which proves to be considerably efficient, achieving more than 85% (6 washing cycles) and 95% (10 washing cycles) of total removal efficiencies for medium and highly contaminated soils respectively under ambient temperature, soil/liquid ratio 1:2.5, 700 ppm and relatively short duration. As that for the fish broth, 94% and 96% removal were achieved in a parallel experiments. Though fish broth has achieve higher efficiency, anaerobic compost tea is chosen for the cost consideration. Those high efficiencies of anaerobic compost tea washing can be explained by the collision and penetration effects brought about by an innovatively designed combination of mechanical agitation and ultrasonic power; therefore, the partitioning between the particles and anaerobic compost tea rises benefiting the treatment. It is the first time a natural solvent is used for dioxin contaminated soil washing. Anaerobic compost tea, which is rich of bio-surfactants, e.g. alcohols, humic acids, etc., provides no harm to the environment during the treatment and also possesses the ability to improve bioavailability and bioactivity of the soil so that further bio-attenuation and full recuperation may take place in a faster manner. The feasibility of degrading highly dioxin contaminated field soil by the aerobic co-composting process with food waste. The initial toxic equivalent quantities (TEQ) of the soil was 16,004 ng-TEQ/kg dry weight, which then decreased to 7,642 after mixing with the bulking agents. The final TEQ value after 42 day incubation was 1,916 ng-TEQ/kg dry weight (approximately 74.3 % degradation) which is still higher than the standard limit (1,000 ng-TEQ/kg dry weight). Profiles of temperature, moisture, pH and ammonia presented favorable conditions for aerobic organisms. In another attempt, a washing soil with initial dioxin concentrations at 2,491 ng-TEQ/kg after mixing with foodwaste at 1:3 ratio has demonstrated 69.9% of removal in 63 days, and the residual concentration was 751 ng-TEQ/kg that is lower than the 1,000 ng-TEQ/kg regulatory limit. Above findings have demonstrated the feasibility in combining anaerobic compost tea washing and the aerobic organic waste composting techniques to remediate dioxin contaminated field soils. The proposed technologies serve as alternatives in choosing greener technology for remediation other than traditional thermal treatment approach. In order to meet the regulatory control limit, a treatment train consists of anaerobic compost tea washing, followed by organic waste composting is proposed.