都市垃圾焚化集塵灰以磷酸穩定配合添加黏土燒結資源化之研究

Sintering Regeneration of MSWI Cyclone Ash by Phosphoric Acid Stabilization Accompany with Clay Blending

葉依婷(Yi-Ting Yeh)

指導教授 ： 高思懷

淡江大學/工學院/水資源及環境工程學系碩士班/碩士(2005年)

https://doi.org/10.6846/TKU.2005.00703

摘要

目前國內都市垃圾以焚化處理為主，隨著垃圾焚化將會產生大量的焚化飛灰，預計在民國95年全台灣將會有27座焚化廠，處理容量將達到每日25,400公噸，其中飛灰部分每年大約會產生30萬公噸，故處理數量龐大的飛灰將成為刻不容緩的課題，需應用更有效安定化及資源化技術，以降低處理運送及掩埋成本與環境風險。同時，更進一步地採取回收再利用的新策略與新技術，以達成資源再利用的目標。
本研究研究材料來自北部一大型焚化廠，先以水萃流程去除集塵灰中的可溶性鹽類，並且以不同濃度的磷酸加以穩定，了解重金屬的穩定情況，探討添加黏土燒結對試體資源化特性之變化，以尋求最適當的燒結操作條件，並且經由熱蒸發實驗，了解添加磷酸對重金屬在熱處理中揮發的影響。
由實驗結果得知，磷酸在燒結前對重金屬具有穩定的效果，尤其對重金屬鉛的穩定效果最為明顯。集塵灰在經過液固比20水洗後並以磷酸穩定再經燒結處理，其試體的資源再利用可行性比水洗前大幅提升，而試體的TCLP也均符合法規標準。再經由熱蒸發實驗得知，重金屬鉛分別在未添加及1.5 mole/kg磷酸添加量穩定下，其重金屬揮發量由21.7 %降至1.2 %，為抑制揮發效果最為顯著的重金屬，並且由結果可以得知，磷酸添加濃度越高，重金屬越不易揮發。

關鍵字

集塵灰 ； 水萃 ； 燒結 ； 黏土 ； 磷酸 ； 熱蒸發

並列摘要

Incineration has become the main way for disposing urban garbage in Taiwan. Till 2006, there will be 27 large municipal solid waste incineration plants in Taiwan, and more than 30, 0000 tons incinerator fly ash will produced which need to be treated and disposed each year. Solidification is used to apply in the fly ashes handling, but the product is still unstable. This study investigated the fly ash stabilizing and sintering to reach the goal that increases the great value of reuse.
The cyclone ash used in this study was collected from the municipal solid waste incineration in north Taiwan. In order to decrease solubility salts, the cyclone ash was treated by water-extraction. Mix clay and cyclone ash which stabilizing with phosphoric acid, and sintering. To find the optimum conditions though discuss the sample variation of source quality. Moreover, interpret the effect of add phosphoric acid to the sample by the evaporation experiment.
The results showed that, stabilizing with phosphoric acid has well effect especially to lead. The sample which pre-washed cyclone ashes possibility of recovery has promoted before water-extraction and sample was conform to the Toxicity characteristic leaching procedure (TCLP) standard. In the evaporation experiment, and sintering at 1100 °C, adding clay and 0 mole/kg phosphoric acid stabilization increases to 1.5 mole/kg, the evaporation ratio of Pb drop 21.7 % to 1.2 %. Add phosphoric acid solution could reduce the heave metal evaporation during the sintering process. By sintering, sample could attend to compressive strength (100 kgf/cm2) and durability standard (weight loss under 12 %).

並列關鍵字

cyclone ash ； water-extraction ； sinter ； clay ； phosphoric acid ； evaporation

參考文獻

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