Reject recovery reverse osmosis (R2RO)

Abstract

A process for the recovery of purified water from a reverse osmosis reject stream includes preconditioning a reject stream to remove scaling ions and provide preconditioned water; separating any precipitate that forms in the preconditioned water to form a feed stream; subjecting the feed stream to high pressure membrane filtration system including a recirculating, high pressure pump generating a permeate stream and a second reject stream; adding a make-up water stream to the feed stream; and separating the permeate stream as purified water. Additional features and embodiments are also provided.

Description

[0001] Cross-references to related applications [0002] This application claims priority from U.S. Provisional Patent Application No. 61 / 869,204, filed on August 23, 2013. This application is incorporated herein by reference. Technical field [0003] Embodiments relate to methods for treating water. Background technology [0004] In the last two decades, effluent treatment, recycling and reuse have become standard. Recently, however, disposal standards have become more stringent, and in many cases and in many countries, zero liquid discharge (ZLD) facilities are typical. [0005] ZLD basically means that the effluent is first treated in a series of treatment equipment that extracts the maximum possible usable water. The concentrated smaller stream, rich in contaminants, is then passed to a heat-based evaporation system or solar pool. These options are highly capital intensive. Therefore, it is necessary to minimize the flow into the heat-based evaporation system or sol...

AI Technical Summary

Problems solved by technology

In some places, waste streams cannot be disposed of due to local environmental regulations

This also sometimes leads to water loss in water-scarce areas and can cause environmental damage in the long run

[0007] Any additional recovery of water is often hindered by fouling potential of pollutants as well as salts and osmotic pressure limitations (resulting from solute concentrations exceeding their limits), making the concentrated stream less suitable for any additional membrane processing

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