Deep filtering paperboard, preparation method of deep filtering paperboard, and pre-filtering system and process applying deep filtering paperboard

The invention relates to the field of filtering paperboards, in particular to a deep filtering paperboard, a preparation method of the deep filtering paperboard and a pre-filtering system and process applying the deep filtering paperboard, the deep filtering paperboard comprises cellulosic fibers and a binding agent used for binding the cellulosic fibers, and the deep filtering paperboard contains positive charges; the effective filtering area of the filter is 4.5 * 10 m < 2 >, the thickness of the filter is bcm, the filter is flushed with an ultrapure water source at the room temperature at the flow speed of 600 LMH, and when the flushing amount reaches 1.4 * 10 L/cm < 3 > or above, the conductivity of flushing liquid is measured to be lower than b * 43 muS.cm ; the effective filtering area of the filter is 4.5 * 10 m < 2 >, the thickness of the filter is bcm, an ultrapure water source penetrates through the filter at the constant pressure of 100 kPa and the temperature of 20 DEG C, an