EFFECT OF VARIOUS POZZOLANS ON PROPERTIES OF THE SOLIDIFIED WASTES
Keywords:
Pozzolans, plating sludge, strength, settingAbstract
The effects of pozzolanic materials on the properties of cement-based solidified plating sludge werestudied. Black rice husk ash (BHA), pulverized fuel ash (PFA) and synthetic rice husk ash (sRHA) wereused at 20 wt% to replace ordinary Portland cement (OPC). Electroplating sludge was added to thesolidification binders at 30 and 50 wt%. Compressive strength, setting time, and static leaching testwere determined. Results showed that the plating sludge could be loaded to the solidification binderscontaining PFA, and gave a 1-day strength that meets the minimum requirement for landfilling (3.5 kg/cm2), but no strength was developed during the first 7 days for the control. Rapid initial and finalsetting times were observed from OPC/BHA/PS and OPC/PFA/PS mixes except for OPC/sRHA/PSmixes. Results on leaching test found that cumulative concentration of interested heavy metals (Zn, Cr,and Fe) especially chromium does not exceed the regulatory limit of 5 mg/L.
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