Arc sieves

An arc sieve (screen) is made of steel plates with a wedge-shaped cross-section, due to which the size of the holes increases in the direction of passage of the material through the screen.

The sludge coming out of the mill is pumped to the distribution gate of the arc sieve. From where, through the inlet device 5, it enters a sieve with a slit of 0.3 mm. Moving along the sieve, the sludge is divided by size into two fractions: fine and coarse. The fraction (finished product) passes through the slots between the grates of the sieve into a feed cavity, divided into two chambers, and flows by gravity through the outlet pipes 6, located at the beginning and end of the sieve arc, into the pit of the finished product. A large fraction (screen product) leaves the screen through pipe 7 and flows by gravity into the mill via a slurry pipe.

The sludge enters the sieve at a pressure of 150-170 kPa tangentially and moves at a fairly high speed, as a result of which its intensive separation is achieved.