US 11,697,602 B2
Techniques for managing scale formation in water filtration systems and a reverse osmosis (RO) and nanofiltration (NF) system implementing same
Stanton Russell Smith, Waltham, MA (US)
Assigned to CTX, LLC, Billerica, MA (US)
Filed by CrossTek Membrane Technology LLC, Billerica, MA (US)
Filed on Sep. 10, 2021, as Appl. No. 17/471,380.
Application 17/471,380 is a continuation of application No. 17/247,986, filed on Jan. 4, 2021, granted, now 11,117,813.
Application 17/247,986 is a continuation of application No. 15/733,581, previously published as PCT/US2020/034674, filed on May 27, 2020.
Claims priority of provisional application 62/991,393, filed on Mar. 18, 2020.
Prior Publication US 2022/0064021 A1, Mar. 3, 2022
Prior Publication US 2023/0140839 A9, May 4, 2023
Int. Cl. C02F 1/00 (2023.01); C02F 1/44 (2023.01); B01D 61/02 (2006.01); B01D 61/12 (2006.01); B01D 65/08 (2006.01); B01D 65/02 (2006.01)
CPC C02F 1/008 (2013.01) [B01D 61/025 (2013.01); B01D 61/027 (2013.01); B01D 61/12 (2013.01); B01D 65/02 (2013.01); B01D 65/08 (2013.01); C02F 1/441 (2013.01); C02F 1/442 (2013.01); B01D 2311/14 (2013.01); B01D 2313/18 (2013.01); B01D 2313/243 (2013.01); B01D 2321/02 (2013.01); B01D 2321/16 (2013.01); C02F 2201/005 (2013.01); C02F 2209/03 (2013.01); C02F 2303/16 (2013.01); C02F 2303/22 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A filter system comprising:
at least one inlet fluidly coupled to at least one feed stream;
at least one filter membrane fluidly coupled to the at least one inlet to receive feed water from the at least one feed stream;
at least one pump configured to generate a pressure to displace the feed water from the at least one feed stream into the at least one filter membrane and produce an output permeate stream; and
a controller configured to:
cause a first driving signal to be provided to the at least one pump to cause the generated pressure at the at least one filter membrane that exceeds an osmotic pressure associated with the at least one filter membrane and substantially maintain a first target recovery rate, the first target recovery rate being greater than a maximum non-scaling recovery rate for the at least one filter membrane and having an associated duration of time prior to when a pre-antiscalant maximum non-scaling recovery state is reached for the at least one filter membrane;
determine when the pre-antiscalant maximum non-scaling recovery state is reached for the filter membrane; and
in response to determining the pre-antiscalant maximum non-scaling recovery state is reached, cause one or a plurality of antiscalant doses to be provided to the filter membrane to increase an amount of time between when a post-antiscalant maximum non-scaling recovery state is reached and when subsequent scaling and/or fouling of the filter membrane occurs.