In order to study the effect of Na_2O content on sintered strength of high alkali synthetic ash

the synthetic ash with different Na_2O mass fractions was made into ash column and heated in a tubular furnace. The microcomputer control universal testing machine was applied to test the sintering strength of the synthetic ash

the X-ray diffraction(XRD) and scanning electron microscopy(SEM) were used to detect and observe the mineral composition and microstructure of synthetic ash. The results show that

with the increase of Na_2O mass concentration

the sintered strength of the ash increased

the sodium compounds in the ash gradually changed from albite to nepheline

and the calcium compounds gradually transformed from anorthite to wollastonite and gehlenite. The low temperature eutectic system formed by minerals such as nepheline

wollastonite and gehlenite produced a large amount of liquid phase in the system

promoting the diffusion process of ash particles and increasing the sintering strength of the ash column. With the increase of Na_2O mass concentration

the observed pore size between the ash particles decreased and the surface of the ash particles became more and more smooth.