Slime Stripping Agent Manufacturers

Why Is Antiscalant Added in Reverse Osmosis Equipment?

Before discussing the role of antiscalants in reverse osmosis systems, let’s first understand the process:

Reverse osmosis (RO) water treatment involves multiple filtration stages, including precision filters and activated carbon filters, followed by pressurization and passage through an RO membrane with a pore size of 1/10,000 μm. This membrane separates impurities like industrial pollutants, heavy metals, bacteria, and viruses, transforming higher-concentration water into purified, low-concentration water that meets drinking standards. RO technology offers the highest water purity of all known water treatment methods, almost reaching 100% purity.

The RO membrane is critical in the system. Over time, calcium and magnesium ions in the water precipitate and attach to the membrane, forming scale that clogs the pores. This reduces water production efficiency and damages the membrane. To protect the membrane, an additional chemical dosing system is used to add antiscalant, preventing scale formation and improving system efficiency.

Our RO antiscalant is specifically designed for use in RO, nanofiltration (NF), and ultrafiltration (UF) systems. It prevents membrane fouling, enhances water production, and reduces operational costs.

Features

1. Controls inorganic scaling effectively across a wide concentration range.
2. Does not form insoluble compounds with iron, aluminum oxides, or silica.
3. Inhibits silica polymerization and deposition, with SiO2 concentrations up to 290 ppm.
4. Compatible with RO CA and TFC membranes, NF membranes, and UF membranes.
5. Excellent solubility and stability.
6. Effective in a water pH range of 5-10.

Antiscalant Functions

1. Chelating and Solubilizing Effect: The antiscalant forms negatively charged chains that combine with Ca2+ ions, increasing the solubility of inorganic salts and preventing scaling.

2. Lattice Distortion: Functional groups in the antiscalant molecules attach to crystal nuclei, disrupting crystal growth and reducing scale formation.

3. Electrostatic Repulsion: The antiscalant adsorbs on salt microcrystals, increasing repulsion between particles and preventing aggregation, which helps keep salts in a dispersed state.

4. Scale Prevention: Antiscalants and dispersants prevent mineral salt precipitation and scale formation.

Applications of RO Antiscalants

1. Polyacrylic Acid-Based Antiscalants: Caution is needed with high iron content as it may cause membrane fouling, which requires acid cleaning.

2. Cationic Coagulants in Pretreatment: Be cautious when using anionic antiscalants, as they may cause sticky contamination, increasing operating pressure and making cleaning difficult.

3. Prevents Salt Crystallization: Antiscalants allow salts to exceed their saturation limits in the concentrate without crystallizing. They can replace or complement acid dosing.

4. Dosing Amount: The ideal dosage should be determined using specialized software from the supplier. Overdosing can lead to new fouling problems, so the system must be properly flushed during downtime.

5. Injection System Design: Ensure thorough mixing of antiscalants and dispersants before reaching the RO membranes. Static mixers are highly effective for this purpose.

6. Dosing Pump: Set the pump to the highest injection rate, typically dosing at 2-5 ppm. Diluted antiscalants should be used within 7-10 days to prevent biological contamination. Antiscalants must be compatible with the RO membrane to avoid irreversible damage.