Chemical Industry

Chlor-Alkali Process: Brine Purification & Filtration Analysis

2026-08-10 1

The objective of brine purification is to remove impurities such as calcium, magnesium, and sulfate from raw salt, providing high-quality primary brine for ion-exchange membrane electrolysis. Precise control of brine chemistry is critical to prevent membrane fouling, extend operational life, and optimize electrolysis efficiency.

1. Key Process Control Points

Effective purification relies on continuous monitoring of chemical and physical properties throughout the pretreatment stages.

Item	Process Location	Parameter	MZD Analytical Strategy
1	Raw Salt	Moisture	Electromagnetic moisture analyzer (control ≤3%).
2	Dissolved Salt Brine	pH	Solid-state reference electrode pH analyzer (range 9–11).
3	Dissolved Salt Brine	Turbidity	Corrosion-resistant turbidity meter (range 0–100 NTU).
4	Dissolved Salt Brine	ORP	Solid-state reference electrode ORP analyzer (reflects reducing substances).
5	Clarification Tank	Turbidity	Turbidity analyzer (evaluating clarification performance).
6	Sand Filter Outlet	Turbidity	Turbidity analyzer (ensure ≤5 mg/L).
8	Gore Membrane Filter	Turbidity	Turbidity analyzer (ensure ≤1 mg/L for high purity).
10	Reaction Tank	pH	Split-type solid-state pH analyzer for magnesium removal optimization.

2. Advanced MZD Instrumentation for Brine Applications

MZD Analytik provides specialized sensors designed to withstand the harsh, high-salinity environments characteristic of brine processing.

Solid-State Reference pH/ORP Analyzers

Traditional pH electrodes often suffer from KCl diffusion and junction contamination in high-salinity brine. MZD’s solid-state reference technology utilizes an electrochemically active, non-porous polymer junction that eliminates electrolyte leakage and clogging.

Performance: <5-second response time and <1 mV monthly drift.
Benefit: 3–5 times longer service life than conventional electrodes, maintaining ±0.05 pH control accuracy in high-salinity media.

Corrosion-Resistant Turbidity Meters

Our turbidity solutions utilize a corrosion-resistant optical structure to provide high accuracy in measuring suspended solids in brine, even after filtration processes. This is essential for monitoring the health of Gore membrane filters and protecting downstream chelating resin towers.

Electromagnetic Moisture Analyzers

For raw salt feed, our non-contact electromagnetic moisture analyzer monitors moisture on the conveyor belt. By maintaining moisture levels ≤3%, plants can significantly reduce steam consumption during the dissolution process, optimizing overall energy efficiency.

3. Operational Benefits

Membrane Longevity: By strictly controlling brine purity, MZD instrumentation directly protects the expensive ion-exchange membranes from scaling and poisoning.
Reduced Maintenance: The maintenance-free nature of our solid-state reference electrodes reduces manual intervention in high-salinity and strongly corrosive areas.
Process Optimization: Precise pH and ORP monitoring allows for tighter control of chemical dosing, reducing chemical consumption by 15–20%.

For detailed technical datasheets or site-specific application consultation, please contact our support team at sales@mzdd.de.

PREVIOUS : Chlor-Alkali Process: Chlorine Handling & Liquid Storage Analysis NEXT : Chlor-Alkali Process Analysis Solutions