Abstract
This research investigated the performance of lime-BHA (black rice husk ash) solidified plating sludge with 2 wt% NaO from Na 2SiO 3 and Na 2CO 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 2SiO 3 and Na 2CO 3 had higher early strength when compared to the control. The addition of Na 2SiO 3 and Na 2CO 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 2SiO 3 resulted in the formation of calcium silicate hydrates, while the addition of Na 2CO 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 2SiO 3 solidified wastes, while samples with Na 2CO 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 2CO 3.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
