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Nanofiltration System

Between UF & RO Selective rejection Divalent salt removal HMI · SCADA

Ahura Aqua designs and manufactures nanofiltration systems for industrial duties across wastewater recovery, food & beverage, and pharmaceutical manufacturing.

NF shares reverse osmosis' fundamentals — a concentrated solution forced through a semi-permeable membrane under pressure — but its 0.01–0.001 µm pores sit squarely between UF and RO, opening selective separations the others can't reach economically.

The NF Advantage · Selective by Design
It Chooses What to Keep
›Nanofiltration rejects organics above ~200–400 Da and divalent salts like MgSO₄ at 90–98%, while letting monovalent salts (NaCl, CaCl₂) pass at just 20–80%. That tunable selectivity unlocks niche separations — colour, hardness and organics removal with partial desalination — that RO and distillation can't deliver economically.
›The NF gap: partial desalination — keep beneficial monovalent salts, strip divalents & organics.
Capacity · 4″ Module
10 – 150
m³/day
Capacity · 8″ Module
500 – 3200
m³/day
Membrane Pore Size
0.01 – 0.001
micron
Organic Cut-Off
> 200 – 400
Daltons
Operating Pressure
≤ 300
psi
Where NF Sits Larger pores → smaller pores
NF sits between UF — which passes more salt — and RO, which passes less. It blocks organics and divalent salts while partially passing monovalent salts.
UF
Ultra-filtration
0.01 – 0.10 µm
Bacteria, viruses, colloids
NF This system
Nano-filtration
0.01 – 0.001 µm · > 200 – 400 Da
Organics, divalent salts, hardness
RO
Reverse Osmosis
~0.0001 µm
Dissolved monovalent salts & ions
Working Principle
Feed (Pre-Filtered)
High-concentration solution under forced pressure
→
Semi-Permeable NF Membrane
Pressure-driven separation
≤ 300 psi · > 200 – 400 Da
→
Selective Permeate
Organics & divalents removed
Monovalent salts partly pass through
As with all membrane separation, a robust pre-filtration stage protects the membrane and sustains rejection performance.
What It Rejects
Contaminant Classes
Dissolved organics Endotoxins / pyrogens Insecticides / pesticides Herbicides Antibiotics Nitrates Sugars Latex emulsions Metal ions
Salt Rejection
Monovalent · NaCl, CaCl₂ 20 – 80%
Divalent · MgSO₄ 90 – 98%
The valence gap is the lever — partial desalination tuned to the duty.
Typical Applications
Colour Removal
Strips colour bodies from process and effluent streams.
Organic Content
Eliminates dissolved organic load selectively.
Total Hardness
Removes hardness through high divalent rejection.
TDS Reduction
Lowers total dissolved solids with partial desalination.
Protein & Whey Concentration
Concentration duty across the dairy industry.
COD Reduction
Organic & inorganic COD reduction in wastewater applications.
Industries Served
Dyes & Paints Textile & Polyester Dairy Processing Wastewater — API / WFI / Formulations Chrome Recovery