Study on the Useful of Scrubber Residue from Municipal Solid Waste for the Fine Aggregate of Concrete

点击翻译按钮获取中文摘要

Scrubber residue of dry scrubber systems from combustion of municipal solid waste (MSW) are almost disposed in ground after the intermediate process. Because MSW incinerator residue show high pH values when brought in contact with water, and high-density chloride, and heavy metals such as Pb are leached. However, the resource recycling of MSW incinerator residue are recently required because of the shortage of the land fill lot and the environmental pollution. This report investigates the role of MSW incinerator residue on the corrosion of steel bars in concrete, and leaching heavy metals from concrete. To study the effects of MSW on the freeze-thaw resistance and the chloride penetration, the accelerated carbonation test and the freezing and thawing test were performed. In the experiments, the water-cement ratio was set to 0.55. The percentages of cement replacement by MSW were selected as 0, 10, 20 and 50% weight. Slump loss of MSW concrete was compensated by the use of a air-entraining and high-range water-reducing agent.The results of the experiments are summarized as follows :(1)As for leaching of incineration fly ash, Pb is reduced by aging, while Pb and Cl^- are reduced by washing of incineration fly ash.(2)The compressive strength of concrete containing incineration fly ash is comparable to that of concrete with no fly ash, though the values slightly vary depending on the fly ash treatment method.(3)Both the carbonation depth and chloride content of concrete containing aged incineration fly ash tend to increase as the ash content increases.(4)The quantity of elution of lead from the concrete which replaced sea sand in destruction by fire ash satisfied soil environmental standard in all substitution rates.