粘土砂铸造除尘灰改性热硬化水玻璃砂

Modification of the Thermo-Hardening Sodium Silicate Sand by Clay Sand Foundry Dust

为实现铸造除尘灰的回收利用,尝试将不同粒径和含量的粘土砂铸造除尘灰用于热硬化水玻璃砂改性,取得了初步效果。结果表明:铸造除尘灰作为改性剂能够提高水玻璃砂的24 h抗压强度,并降低水玻璃砂的残留强度;当铸造除尘灰粒径约为25μm,总加入量为原砂重的0.9%时,水玻璃砂具有较好的综合性能,其24 h抗压强度为1.42 MPa,残留强度为0.23 MPa。

In order to realize the recycling and utilization of foundry dust, the clay sand foundry dust with different particle size and content was used to modify the thermo-hardening sodium silicate sand, and preliminary results were obtained. The results revealed that as a modification, the foundry dust can actually promote the 24 h compression strength of the sodium silicate sand, and decrease its residual strength. When the particle diameter of foundry dust is 25 μm and the addition is 0.9% of the weight of the sand, the sodium silicate sand has superior mechanical properties, whose 24 h compression strength reaches 1.42 MPa and residual strength reaches 0.23 MPa.