Patent ID: 9199866
Filing Date: 2015-12-01
Classification: B01D,B01J,C02F

Abstract:
1. A High Recovery Drinking Water Process that treats influent water and produces reverse osmosis membrane permeate recoveries in the range 90%-99% of an influent water volume, comprising: providing a High Recovery Drinking Water System comprising: a) a reverse osmosis (RO) membrane system used to purify influent water and produce membrane permeate product water and membrane concentrate; b) two ion exchange (IX) water softening resin columns, each connected to said RO membrane system and configured to both provide low-hardness influent water to said RO membrane system and receive said membrane concentrate from said RO membrane system to produce recycled low-hardness membrane concentrate; c) an anti-scalant metering unit or silica sequestering unit to prevent silica scale formation; d) a cartridge filter with a maximum nominal filter porosity of 5 microns; e) one or more pressurizing pumps used to pressurize and transfer said influent water to said RO membrane system and to said two IX water softening resin columns; f) a brine tank to collect said membrane concentrate and augment ionic strength of said membrane concentrate via salt addition; and g) control valves selected from the group consisting of automated motorized valves, solenoid valves, air-operated shut-off valves, and combinations thereof, wherein the control valves are opened and closed automatically in a predetermined sequence, and wherein said control valves are configured to enable flow streams that alternate which of said two IX water softening resin columns is a first pre-membrane ion exchange (IX) water softening resin column to remove bulk hardness and other multivalent cations from said influent water; opening and closing the control valves in a manner and with a timed sequence of operations as to provide a pre-membrane influent water IX softening, RO purification and post-membrane recycled membrane concentrate IX hardness polishing (IXA-RO-IXB process), designated as Normal Water Production Cycle (Mode 1), comprising: opening and closing the control valves in a manner and with a timed sequence of operations as to provide a pre-membrane influent water IX softening, RO purification and exhausted IX resin (IXA) regeneration using the membrane concentrate (IXB-RO-IXAR process), designated as Water Production and IX Resin Regeneration Cycle (Mode 1), comprising: opening and closing the control valves in a manner and with a timed sequence of operations as to provide a pre-membrane influent water IX softening, RO purification and post-membrane recycled membrane concentrate IX hardness polishing (IXB-RO-IXA process), designated as the Normal Water Production Cycle (Mode 2), comprising: opening and closing the control valves in a manner and with a timed sequence of operations as to provide a pre-membrane influent water IX softening, RO purification and exhausted IX resin (IXB) regeneration the membrane concentrate (IXA-RO-IXBR process), designated as Water Production and IX Resin Regeneration Cycle (Mode 2), comprising: