Abstract:

The properties of cement with the incineration bottom ash of municipal solid waste as the admixture were investigated, and the environmental safety of the cement product was analyzed. The results show that （ 1 ） the bottom ash is an inactive admixture without radioactivity, which has no obvious influence on the cement soundness, the water consumption of standard consistence and the cement setting time ; （2） the compressive strength of the cement decreases with the increase of bottom ash dosage; （3） washed bottom ash has a relatively slight influence on the compressive strength; （4） a bottom ash dosage of 7.5% is suitable for the production of P ·O42.5 cement; （5） though the bottom ash has no obvious influence on the compatibility with superplasticizer, it reduces the shrinkage rate without arousing a steel corrosion; （6） at a bottom ash dosage of 15% -40% or 80%, the leaching limit of heavy metals in mortar reaches the standard of groundwater type Ⅲor type Ⅳ, respectively ; and （7） at a bottom ash dosage of 15%, the surface leaching of heavy metals in mortar also reaches the standard of groundwater type Ⅲ. It is thus concluded that the addition of bottom ash in cement does not bring about any harm to the environment and human health.

Key words: municipal solid waste, solid waste incineration, bottom ash, admixture, cement property, environmental safety