Combining with the physical model of deep bed filtration and using conception of filtration bed cells, mathematic model of filtration resistance and filtration velocity of deep bed filtration under constant pressure is established.

The present paper comprehensively introduced the difference between extruded ceramic filter and foam filter through filtration efficiency, consistent flow rate, good strength, high capacity and costs.

the present paper comprehensively introduced the difference between extruded ceramic filter and foam filter through filtration efficiency,consistent flow rate,good strength,a high capacity and costs.

Then the higher filtration intensity, productive capacity and the phosphorus recovery are obtained for the employment of filter aid in the filtration systems of the abovementioned 2 sets of phosphoric acid facilities with dihydrated phosphogypsum process and 1 set with the dihydrated phosphogypsum section of semidihydrated ph.

The influences of various thin slurries with different solid particle sizes on filtration intensity are discussed.

The test results showed:(1)Using the suitable aid can increase the filtering rate effectively and the yield of dewaxing oil,decrease the oil content of slack wax and improve the quality of slack wax,without influenc.

The filtration speed, the yield, DE value and transparence of sugar liquid from these two crafts were measured and analyzed.

And the filtration speed is very fast.

It is proved by the spot experimental research that based on pressure filter which is presently used in natatoriumsthe geminate improvement of filtration speed will not give an impact on the outflow water quality and filtration efficiency.