以酒廠污泥備製可溶性有機碳溶液復育砷污染土壤之研究

Remediation of Arsenic-contaminated Soil Using Dissolved Organic Carbon Solution Originating from Wine-processing waste

劉鎮宗(Cheng-Chung Liu) ； 張家銘(Chia-Ming Chang) ； 謝佩盈(Pei-Ying Hsieh)

《國立宜蘭大學工程學刊》 10期 (2014/12) Pp. 13-23

https://doi.org/10.6176/BCE.2014.10.12

摘要

根據前人研究指出利用酒廠污泥萃取之可溶性有機碳溶有利於復育重金屬污染之土壤，且保留其地力。已知酒廠污泥除富含營養物質，其高含量的有機質可有效錯合並吸附水中重金屬。本研究以酒廠污泥配製可溶性有機碳清洗液，復育砷污染農地（390 mgkg^(-1)）之土壤樣體。根據萃取固液比（S/L）1：40、pH 10、室溫（20℃）、120 rpm振盪萃取60分鐘、清洗2次等操作條件，探討砷的移除率以及處理前後的土壤肥力變化。以2500 mg L^(-1)的可溶性有機碳溶液處理，其一次與二次清洗的移除率分別為52.2%及20.6%，清洗後土壤之砷含量為106 mg kg^(-1)，無法降至土壤污染管制標準值（60 mg kg^(-1)）；改為3000 mg L^(-1)的可溶性有機質溶液處理，第一次與第二次清洗的移除率分別為58.7%及29.4%；土樣中砷含量則降至45 mg kg^(-1)，結果顯示在高濃度清洗的條件下，可將砷含量降至管制標準值內。而經可溶性有機碳溶液二次清洗後的土壤樣體，其有機質增加為原來的1.2倍；銨態氮增加1.3倍；更效性磷含量增加6.5倍；交換性鉀增加91倍；交換性鈉則增加4.5倍；其交換性鈣則增加4.2倍；交換性鎂則增加2.2倍。顯示經可溶性有機碳溶液的清洗，較更利土壤肥力之維持。

關鍵字

砷 ； 可溶性更機質 ； 污泥 ； 土壤清洗法

並列摘要

Dissolved organic carbon (DOC), extracted from distillery sludge, washing has been proved that it could remove heavy metals effectively from a contaminated soil and reserve most fertility in soil. The distillery sludge not only contained abundant essential nutrients but also had high content of organic carbon which could adsorb toxic metals from an aqueous solution. The aim of this study was employing the DOC solutions prepared by the distillery sludge for remediation of a soil severely contaminated with As (390 mg kg^(-1)). The removal of As and the variation in soil fertility during the washing were identified at pH 10, an 80:1 liquid/soil ratio (v/v), and 20 °C with 120 rpm for 60 min by two washes. Approximately 52.2 and 20.6% of As were respectively removed by the first wash and the second wash employing the 2500 mg L^(-1) DOC solution; the As concentration in soil became 106 mg kg^(-1), which is still higher than the control threshold value, 60 mg As kg^(-1). However, about 58.7% and 29.4% of As were removed respectively for the first wash and the second wash using 3000 mg L^(-1) DOC solution; it was calculated that only 45 mg As kg^(-1) was remained after such washing and this result met the control standard. Meanwhile, organic matter, NH4 +-N, available P as well as exchangeable K, Na, and Ca contents increased 1.2, 1.3, 6.5, 45, 3.8, and 1.4 times their original contents after the DOC washing twice, respectively; the increase in exchangeable Mg content was slight.

並列關鍵字

As ； Dissolved organic carbon ； Sludge ； Soil washing