Experiments with distinct force distributions on the surface have been conducted and the experimental results show that the variation of SAW resonant frequency is related with the surface stress produced by surface force loading and the mechanical loss of a resonator is related with the force distribution when the back surface of th.

The influence of air-water ratio,HRT(hydraulic retention time),media-filling rate for biological contact oxidation tank and dosage of flocculating agent,surface loading for flotation tank on pollutants removal was studied.

It is believed that in designing the secondary sedimentation tanks for extended aeration systems, in addition to the calculation on the basis of surface load, the factor of solid load also should be taken into consideration.

In sorting out the experimental data of coagulating sedimentation,manual calculation and curving are usually used to find out the relationship among the removal rate C,the surface load u0 and the residence time t.