US 12,441,629 B2
Flow control for reverse osmosis filter
Tommaso Montanari, Forli (IT)
Assigned to Bellco SRL, Mirandola (IT)
Filed by Bellco SRL, Mirandola (IT)
Filed on Sep. 9, 2021, as Appl. No. 17/470,750.
Prior Publication US 2023/0075109 A1, Mar. 9, 2023
Int. Cl. C02F 1/00 (2023.01); B01D 61/02 (2006.01); B01D 61/12 (2006.01); B01D 61/54 (2006.01); C02F 1/44 (2023.01); C02F 1/469 (2023.01)
CPC C02F 1/008 (2013.01) [B01D 61/025 (2013.01); B01D 61/12 (2013.01); B01D 61/54 (2013.01); C02F 1/441 (2013.01); C02F 1/4695 (2013.01); B01D 2311/06 (2013.01); B01D 2311/14 (2013.01); B01D 2311/243 (2013.01); B01D 2311/2684 (2013.01); B01D 2313/18 (2013.01); B01D 2313/243 (2013.01); C02F 2201/005 (2013.01); C02F 2209/003 (2013.01); C02F 2209/03 (2013.01); C02F 2209/05 (2013.01); C02F 2209/40 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A system for water filtration, comprising:
a reverse osmosis filter having a semipermeable membrane;
a feed line, a permeate line, and a concentrate line, each in fluid communication with the filter;
a pump at the feed line pumping feed water into the filter;
a flow sensor configured to monitor a flow rate of permeate water exiting the filter into the permeate line;
a permeate sensor configured to monitor a property of the permeate water;
an adjustable valve configured to regulate a flow rate of concentrate water exiting the filter into the concentrate line; and
a pressure sensor configured to detect a pressure that correlates with permeate water flow; and
at least one controller configured to control:
a first feedback circuit configured to 1) compare the flow rate of the permeate water with a target flow rate of the permeate water and 2) calculate a reference pressure based on a difference between the flow rate of the permeate water and the target flow rate of the permeate water,
wherein the flow rate of the permeate water is based on at least the pressure of the feed line;
a second feedback circuit configured to 1) compare the pressure from the pressure sensor to the reference pressure calculated by the first feedback circuit and 2) regulate a flow rate of the feed water to adjust a pressure of the feed line towards the reference pressure calculated by the first feedback circuit,
wherein the second feedback circuit operates at a higher frequency than at least the first feedback circuit; and
a third feedback circuit configured to regulate the flow rate of the concentrate water exiting the filter into the concentrate line based on the property monitored by the permeate sensor.