利用建筑陶瓷废渣制备硅酸盐蒸压砖的研究

Research on preparation of silicate autoclaved brick with architectural ceramic waste residue

以建筑陶瓷废渣为主要原料制备硅酸盐蒸压砖,探讨了骨料和石灰掺量、成型压力和成型用水量对制品性能的影响,通过正交试验确定了原料最佳配合比,利用XRD、SEM和EDS研究了制品强度的形成机理。结果表明,物料配比、成型用水量及成型压力皆对制品性能有一定的影响,按m(陶瓷废渣粉)∶m(石灰)∶m(骨料)∶m(引晶剂)∶m(水玻璃)=50∶15∶33∶2∶0.5配料,加18%水搅拌均匀,25 MPa下压制成型,饱和蒸汽1.2 MPa下恒温6 h制备而成的蒸压砖,其抗压强度达44.5 MPa;原料中的SiO_2与CaO水热反应生成托贝莫来石、CSH(B)和C-S-H凝胶等水化物,包覆在固体颗粒表面或填充在颗粒之间,相互交织连接形成了坚实的胶结体,由此构成了材料的整体强度。

Silicate autoclaved brick was prepared by using architectural ceramic waste residue as raw materials. The effects of aggregate and lime eontent,formirig pressure and forming water content on the properties of the products were discussed. The mixing ratio of raw materials was determined by orthogonal experiment. And the strength of the products forming mechanism was stud- ied by XRD, SEM and EDS. It was shown that material ratio,forming water content and forming pressure had a certain impact on the performance of products. The samples were prepared by compounding materials in accordance with the mass ratio of ceramic waste residue：lime：aggregate：seed crystal：water glass=50：15：33：2：0.5,adding water 18% and under 25 blPa pressure forming, and by autoclaving under hydrothermal conditions with steam pressure 1.2 MPa for 6 h. The compressive strength of autoclaved brick was 44.5 MPa. The hydrothermal reaction between SiO： and CaO in the raw materials produces hydrates such as tobermorite,CSH（B） and C-S-H gel, coated on the surface of the solid particles and/or filled in between the particles, interweaving to form a solid cemented body,thus forming the overall strength of the material.