(57) ABSTRACT A serial filtration system for liquid purification includes a preliminary-stage
reverse-osmosis (RO) module and a first stage, high-permeability, reverse-osmosis (HiRO)
module. Both modules include (a) a chamber including an inlet, a retentate outlet, and a
permeate outlet, and (b) at least one membrane separating the chamber into a retentate side
on an upstream side of the membrane and a permeate side on a downstream side of the
membrane. The membrane in the preliminary stage is an RO membrane, while the …

A serial filtration system for liquid purification includes a preliminary-stage reverse-osmosis
(RO) module and a first-stage, high-permeability, reverse-osmosis (HiRO) module. Both
modules include (a) a chamber including an inlet, a retentate outlet, and a permeate outlet,
and (b) at least one membrane separating the chamber into a retentate side on an upstream
side of the membrane and a permeate side on a downstream side of the membrane. The
membrane in the preliminary stage is an RO membrane, while the membrane in the first …