Due to the high salt content of coal chemical wastewater

pipeline fouling often occurs during wastewater treatment. Fouling will cause the diameter of the pipe to shrink or even block

which is not conducive to the safe and stable operation of the wastewater treatment process. In this paper

the experimental device was designed by using FLUENT software and the fouling deposition mechanisms at different flow velocities and different positions in a 90 deg bend were studied. The experimental results show that when the flow velocity is between 0.2 m·s

-1

and 0.3 m·s

-1

the thickness of fouling layer was positively correlated with the flow velocity; when the flow velocity is equal to 0.4 m·s

-1

the formation of fouling is the most serious; when the flow velocity is between 0.4 m·s

-1

and 0.7 m·s

-1

the thickness of fouling layer was negative correlation with the flow velocity; with the increase of inlet velocity

the time for sediment point to develop into sediment surface is shortened. The fouling layer is easy to fall off because of the large shear force on the wall surface of the inner bend of the 90° elbow

so the density of sediment at

this position is high.