Fineness Effect on Pozzolanic Activity of Cu-Ni Slag in Cemented Tailing Backfill

Wenyuan Xu,Xiaocong Yang,Wenchen Li,Lijie Guo

doi:10.1155/2020/7172890

Abstract

This paper presents the experimental results of the fineness effect on the pozzolanic activity of Cu-Ni slag in cemented tailing backfill. Cement paste and cemented tailing backfill samples that without or contain Cu-Ni slag with various grinding times were made and cured at 20°C for 7, 28, and 150 days. Mechanical test and microstructural analyses are performed. In general, the pozzolanic activity of Cu-Ni slag increases with the fineness of particle size. The strength of cemented tailing backfill samples decreased with the addition of Cu-Ni slag. It was found that the pozzolanic activity of Cu-Ni slag used in this study is relatively low. According to the fineness, the Cu-Ni slag will make the cemented tailing backfill samples looser or denser. For the sample containing ground Cu-Ni slag ground for 30 min to 50 min, the sample becomes dense gradually as the particle size of Cu-Ni slag becomes finer.

Highlights

It can be observed that the strengths of cemented tailing backfill (CTB) are significantly decreased with the addition of Cu-Ni slag. is is due to the reduction of cement content caused by the addition of copper and nickel slag, which leads to the reduction of cement hydration products
66 66 66 66 66 66 pozzolanic activity of Cu-Ni slag increases gradually, which means that the hydration reaction is more sufficient
It is found that the strength of CTB decreased with the addition of Cu-Ni slag, and the pozzolanic activity of Cu-Ni slag is relatively low

Summary

Materials

E Cu-Ni slag used in this study is the waste slag discharged from a Cu-Ni mine in Xinjiang through smelting in a dilution electric furnace. E electric oven was used to dry the Cu-Ni slag, and the ball mill was used for grinding. The Cu-Ni slag was tested and analyzed by laser particle size test. E cement used in this experiment was ordinary Portland PO 42.5 cement. All samples for microstructural analysis were first dried in an oven at 45°C to remove the free water

Results

Findings

Conclusions