Process Description
When liquid flows from inside to the outside, contamination particles then collect on the smooth inside of cartridge. And the level of contamination increases, the differential pressure between the contaminated and clean side of the filter increases. When the differential pressure reaches its pre-set value, the differential pressure indicator send a signal , then the filter start back-washing automatically.
1) The gear motor turns the washing arm through the middle rotation, the photoelectric sensor controls washing arm running angle so that the cartridge being cleaned.
2) The drain valve is opened, which results in a pressure drop between the drain valve and filtrate side.
3) With the pressure drop, fluid flows outside to inside to backwash, the contamination particles collected on the inside of the cartridge are loosened and washed out the filter.
4) A typical back-washing time has been set, as soon as the “back-washing time per cartridge “ has elapsed, the drain valve is closed, a back-washing of this cartridge is terminated. The gear motor turns the washing arm again to backwash the next cartridge, the drain valve be opened again, and so on for each cartridge.
5) All the cartridges are flushed in succession and have been cleaned, the washing arm backs to the original position, a back-washing cycle is terminated.
6) Because for each cartridge back-washing, the filtrate flow is not interrupted during the back-washing procedure.
Flow instruments
