Filtomat EBS Series Automatic Filters
For flow rates up to 4,000 m³/h; 17,600 USgpm
Filtration degrees from 800 to 10 micron
Filter area 10,000 – 40,000 cm²; 1,550 – 6,200 in²
The EBS is an automatic filter, with a self-cleaning mechanism driven by an electric motor. The EBS is designed to work with various types of screens in filtration degrees from 500 To 10 micron, and is available in 8″ To 24″ inlet/outlet diameter.
Unfiltered water flows into the filter through the inlet flange of the filter body. Water Then proceeds through the cylindrical stainless steel filter element (screen) from the inside out causing particulates larger than the filtration degree of the screen to accumulate on the inside surface of the screen, progressively developing a filter cake. The filter cake, in turn, begins to trap particles much smaller than the openings in the screen.
Effluent leaves the filter body through another flanged opening. An adjustable Pressure Differential Switch (PDS) continuously senses the pressure differential across the filter screen. The PDS signals the filter controller to initiate the cleaning cycle of the filter screen when the filter cake causes a pre-set pressure differential.
The filter screen cleaning mechanism is a suction scanner constructed of a 316 stainless steel assembly that rotates while also moving linearly. The suction scanner consists of a central tube with tubular nozzles equally spaced along the length of the central tube positioned perpendicular to the longitudinal axis of the central tube. A 3″ flush valve connects the internal cavity of the suction scanner to atmospheric pressure outside the filter body. By opening the flush valve, the differential gauge pressure between the water inside the filter body and the atmosphere outside the filter body creates high suction forces at the openings of each of the suction scanner nozzles. This suction force causes water to flow backward through the screen in a small area at each nozzle pulling the filter cake off the screen and sucking it into the suction scanner and out the exhaust valve to waste. The high velocity of the water stream entering these nozzles results in ample energy to remove the toughest materials from the screen. The driving mechanism then rotates the suction scanner at a slow, fixed rotation while simultaneously moving the scanner linearly at a fixed speed. The combination of rotation and linear movement gives each suction scanner nozzle a spiral path along the inside surface of the filter screen. The cleaning cycle is completed in approx. 35 seconds. During this time the nozzles remove the filter cake from the entire filtration area of the filter screen, yet filtered water continues to flow downstream of the filter. The filter operation and cleaning cycle is controlled and monitored by a Programmable Logic Control (PLC).