Symbiotic reverse osmosis for maximizing desalinated water recovery from saline waters and brines

Abstract

The present application comprises symbiotic reverse osmosis train system for maximizing desalinated water recovery, meanwhile yielding high salinity brine suitable for osmotic power generation or commercial salt production; trains comprise series of number of cells operating in interrelated sequential pattern within a salinity field. Each cell forms a closed hydraulic brine loop having pumping means, power recovery means and shared semipermeable membranes between adjacent cells, defining the boundaries of flow path within a given cell, using applicant's technology for semipermeable Flat Sheet Membranes [FSM] or Hollow Fiber Membranes [HFM] intended for new and novel development in Hypersalinity processes and applications in desalination and osmotic power generation of brackish, seawater and brines of 15% salinity or more. Charging each cell in the train of plurality of cells with a formulated brine having a specified ionizable inorganic salt concentration and type, without permitting mixing of the given brines among the adjacent cells in the plurality of cells, allowing the train of multiple cells to achieve water recovery exceeding 85% with concentrated rejected brine of 28-30% salt content that is recoverable by evaporation / crystallization for commercial use. Highlighting, the first of its kind, a large scale Seashore Tower of flat Sheet membrane [FSM] for Induced Osmotic Desalination Plant of a capacity 28-56 million cubic meter per year (15 billion gallons per year) at a recovery rate of 85%, and rejected brine salinity of 28-30%, either used for sodium chloride salt recovery of 1-2 million metric tons per year, or to generate Induced Osmotic Power of 25-50 MW.

Description

BACKGROUND[0001]1. Field of the Invention[0002]The present application relates generally to a symbiotic reverse osmosis system using semipermeable flat sheet and hollow fiber membranes panels design.[0003]2. Description of Related Art[0004]In 1959, two researchers at UCLA, Sidney Loeb and Srinivasa Sourirajan succeeded in producing a functional synthetic RO membrane from cellulose acetate polymer and based on this development, the world's first commercial RO plant was built in Coalinga in 1965. Today, reverse osmosis and membrane filtration elements are used for multitude of water treatment processes and applications and many types of membranes are developed and in use worldwide. However, all of these applications are functionally still limited by seawater salinity of 3.5%[0005]This serious operational limitation has promoted the applicant of this invention to consider rather new approach that allows the use of the technology not only for seawater, but also for brines of different c...

AI Technical Summary

Benefits of technology

The patent text describes a new technology for reverse osmosis systems that can use high salinity brine for desalination and osmotic power generation. The technology is based on a Symbiotic Salinity Concept that allows for the use of membrane panels designed to withstand high pressure and salinity. The current commercial membrane panels used for seawater desalination have limitations in terms of mechanical integrity and fouling, which make them unsuitable for high salinity applications. The new technology solves these limitations by using semipermeable flat sheet membranes that can operate at high salinity, allowing for the use of higher salinity brine for desalination and osmotic power generation. The technology also addresses the issue of osmotic pressure and pumping pressure requirements for seawater recovery, which are currently limited to about 7% salinity. The patent text also mentions the use of the Symbiotic Salinity Concept for salinity power generation, but there is no polymeric membrane technology in practice today that can withstand the pressure required for desalination. The technology also addresses the shortcomings of current commercial membrane panels and provides a solution for high salinity applications.

Problems solved by technology

However, all of these applications are functionally still limited by seawater salinity of 3.5%

Spiral wound and hollow fiber membranes are heavily used today in seawater desalination, but these membranes, due to their relatively low mechanical integrity, their compacted assembly and excessive fouling are unsuitable to meet the stringent performance of the aforementioned two objectives.

Eventually, this membrane fails causing remixing seawater with desalinated water.

Therefore, reverse osmosis processes, particularly for high salinity are pressure demanding technologies, requiring the use of multi-stage pumps and pressure vessels.

Further, the current commercial semipermeable membrane maximum operating limit is at or about 7% salinity, which prevents any further development of processes that can make advantage of higher salinity domains such as Great Salt Lake, USA of 24%, or the Dead Sea, Israel of 36% and many others sites worldwide.

The inventor envisioned and patented a technology (U.S. Pat. No. 8,545,701) that employs a Symbiotic Salinity Concept (Induced Symbiotic Osmosis [ISO] for Salinity Power Generation), however, there is no polymeric membrane technology in practice today, or anticipated in the future, that is adequate for commercial desalination that can withstanding the pressure required for desalinating or generating osmotic power from 25% brines at 3000 psi.

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