| The various kinds of industrial solid wastes have done great harm to theenvironment, and their amounts keep growing. So, the disposal of them becomesmore and more important. Red mud is one of the largest pollutants. In order to utilizethis industrial solid waste, the high performances ceramic simple bricks(hollowbricks) based red mud have been made from fly ash, poor clay shale, gangue andsome additives as minor materials in this paper. Especially, two kinds of makingtechniques semi-dry pressing were used in this study.The properties micro structure and crystal phases of the raw industrial solidwastes have been tested by TG-DTA, SEM, XRD and XRFA. The results indicatedthat the red mud is not suit for bricks preparation individually because of itscompositions. But fly ash, poor clay shale and gangue can be preparated simplebricks individually.By the test of performances and microstructure of full wastes samples, it wasfound that the samples were deformed notable when the content of the red mud wasmore than 70% in full wastes samples. The performances of the samples weremeasured by TG-DTA, SEM, XRD and EPMA. The results showed that the fullwastes samples could be preparated with high performances, when the addition ofred mud is 50～70％. And also showed that the bricks with the best performances andmicrostructure (water absorption(Wa) of L-4 is 21.50％, porosity absorption(Pa) is38.56％, density(D) is 1.79g/cm3, the bending strength is 33.93MPa and thecompression strength is 86.95MPa, thermal conductivity(X) is 1.333×10-2W·cm-1·K-1)could be preparated when the content of the red mud is 65％. In the Bayer-sinteredred mud samples of the simple bricks, the content of the red mud is increased to60～90％. And the high performances simple bricks (Wa of BN-7 is 15.67％, Pa is24.69％, D is 1.58g/cm3, the bending strength is 47.11MPa and the compressionstrength is 122.68MPa,λis 2.193×10-2W·cm-1·K-1) have been prepatated.The extrusion technique is another making method of the ceramic manufacturing processes. In this thesis, it has also used to preparated the simplebricks. There are about four aspects, such as the require by extrusion technique onthe compositions of billet, the research on the body plasticity, the factors affectingthe heat-insulating property of hollow bricks and the main problems during theextruding process, ect. It is found that the plasticity of the body were the best whenthe ageing times were 2 days, the plasticity could be markedly increased by addingthe lignosulphonate incorporation, the type of the hollow brick is affecting thestrength and the heat-insulating property of it markedly. The compression strength ofthe hollow brick which has been preparated in this research is 16.36MPa and more, itsurpasses the national standard of the hollow brick MU 10.In ceramic simple brick system, when CaO％was high, which would cause itwas prior generate some Ca-contained mineral such as anorthite and wollastonite,though A1-Si spinel(the mosophase of mullite) would also be generate. But inSintering red mud-Bayer red mud system, CaO％was lower, in which system themain phase was quartz, the enstatite from dehydrate resultant of talc had appeared,though there was also anorthite. And there was also a tendency to generate Al-Sispinel (intermediate phase of mullite). If further increased firing temperature, mullitewould be generated, then such main phase as cordierite would be generated. Becauseof the high content of CaO in sintering red mud system, Mg dissociated from talcexisted in glass-phase of the system, and when Bayer red mud was added, Al2O3％increased while CaO％decreased, then talc would dehydrate to generate enstatite.The reaction mechanism in high temperature of this system corresponded to the ruleof Mg-K(Na)-Al-Si system.
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