Environmental Technology, School of Energy Environment and Materials, King Mongkut's University of Technology Thonburi, Pracha U-thit Rd., Bangmod, Thung-kru, Bangkok 10140, Thailand.
J Environ Manage. 2011 Sep;92(9):2222-8. doi: 10.1016/j.jenvman.2011.04.004. Epub 2011 May 6.
This research investigated the performance of lime-BHA (black rice husk ash) solidified plating sludge with 2 wt% NaO from Na(2)SiO(3) and Na(2)CO(3) at the level of 0, 30 and 50 wt%. The sludge was evaluated for strength development, leachability, solution chemistry and microstructure. The lime-BHA solidified plating sludge with Na(2)SiO(3) and Na(2)CO(3) had higher early strength when compared to the control. The addition of Na(2)SiO(3) and Na(2)CO(3) increased the OH(-) concentration and decreased the Ca(2+) and heavy metal ions in solution after the first minute. The XRD patterns showed that the addition of Na(2)SiO(3) resulted in the formation of calcium silicate hydrates, while the addition of Na(2)CO(3) resulted in CaCO(3). The heavy metals from the plating sludge, especially Zn, were immobilized in calcium zincate and calcium zinc silicate forms for the lime-BHA with and without Na(2)SiO(3) solidified wastes, while samples with Na(2)CO(3) contained Zn that was fixed in the form of CaZnCO(3). The cumulative leaching of Fe, Cr and Zn from the lime-BHA solidified plating sludge decreased significantly when activators were added, especially Na(2)CO(3).
本研究考察了用 2wt%的来自 Na(2)SiO(3)和 Na(2)CO(3)的 NaO 的熟石灰-BHA（黑米稻壳灰）固化电镀污泥的性能，其添加水平为 0、30 和 50wt%。对污泥的强度发展、浸出性、溶液化学和微观结构进行了评估。与对照相比，用熟石灰-BHA 固化的添加了 Na(2)SiO(3)和 Na(2)CO(3)的电镀污泥具有更高的早期强度。添加 Na(2)SiO(3)和 Na(2)CO(3)后，溶液中的 OH(-)浓度增加，Ca(2+)和重金属离子浓度在第 1 分钟后降低。XRD 图谱表明，添加 Na(2)SiO(3)导致了硅酸钙水合物的形成，而添加 Na(2)CO(3)则导致了 CaCO(3)的形成。电镀污泥中的重金属，特别是 Zn，在有和没有 Na(2)SiO(3)的熟石灰-BHA 固化废物中，以钙锌酸盐和钙锌硅酸盐的形式被固定，而含有 Na(2)CO(3)的样品中的 Zn 则以 CaZnCO(3)的形式被固定。当添加活化剂时，熟石灰-BHA 固化电镀污泥中 Fe、Cr 和 Zn 的累积浸出率显著降低，尤其是添加了 Na(2)CO(3。
