|
Abstract The cement rotary kiln co-processing technique is accepted as an effective way to realize the reduction,
harmlessness and resource utilization of solid waste. In this paper, the total amount, morphology analysis and leaching content of heavy metals in solid wastes (fly ash, copper slag, sulfuric acid slag and mixed sludge) and clinker of four production lines of cement kiln co-processing fly ash, copper slag, sulfuric acid slag and mixed sludge were determined. The determinate results showed that the total content of heavy metals in solid waste was very high (e.g. the content of chromium in the mixed sludge even reached 1.8×104 mg/kg), which may cause environment contamination if without proper treatment and stored or discharged directly. In this paper, the speciation analysis of heavy metals (As, Cr, Cd, Cu, Mn, Ni, Pb, Zn) in solid wastes and clinker were determined by means of BCR sequential extraction procedure, which using the independent
invented sequential extraction device. The analysis results showed that the heavy metal forms in solid waste were mainly weak acid extractable and reducible. After calcination in cement kiln, the heavy metal forms in clinker were mainly residual, indicating that the significant fixation effect. In the experiment, the standard method was used to maintain the cement mortar test block, and the cured test block was extracted with the reference cement. The results showed that the risk of heavy metals in cement products produced by cement kiln co-processing solid waste migrating to the environment was low under the existing solid waste addition.
|
|
Published: 29 December 2022
|
|
|
|
2023, Vol. 0 
