Blog – articles about water treatment and more

FreeFlow GREEN - the green antiscalant

Modern antiscalants are subject to the DIN EN 15039 standard for polycarboxylic acids and the DIN EN 15040 standard for phosphonic acids when it comes to their use in the treatment of drinking water by membrane systems.

In addition to the requirements for drinking water production, another requirement profile for the antiscalant can be its biodegradability.

History of Reverse Osmosis

The natural process known as osmosis was first discovered back in 1748 by Jean-Antoine Nollet, a French clergyman and physicist. In his experiments, Nollet used a pig’s bladder as a membrane to show that solvent molecules from low solute water could flow through the bladder wall into a higher solute concentration made of alcohol. Thus, he became the first person to demonstrate the process by which a solvent can pass selectively through a semi-permeable membrane through the process of natural osmotic pressure.

Antiscalants - history and mode of action

The first commercial membranes were made of cellulose acetate. An acidic pH in the feed prevented the membranes from degrading. The acidic pH also prevented calcium carbonate deposits in the concentrate.

Water treatment with (reverse) osmosis plants

Reverse osmosis is a physical process of membrane technology for the concentration of substances dissolved in liquids, in which pressure is used to reverse the natural osmosis process.


Water as a resource

An essential component of sustainable development is the careful and efficient use of natural resources. The entire economic cycle is considered, from the extraction of raw materials to the manufacture and use of products to the recycling and disposal of waste.

Expertise reports from Dr. Nähring Water Treatment GmbH

An expertise is a report written by experts on a specific issue in a particular field. As experts in the field of antiscalants and purifiers for membrane plants, we provide expert reports in the following areas:

Water treatment semipermeable membrane, (reverse) osmosis

In the simplest definition, a semipermeable membrane is said to exist when the membrane allows the solvent, but not the solute, to pass through. More generally, only molecules below a certain molar mass or colloids or particles below a certain size are allowed to pass through.

FreeFlow System Antiscalants from Dr. Nähring Water Treatment GmbH

During the filtration process of a reverse osmosis system, the raw water is separated into permeate and concentrate. Depending on the yield, the water constituents in the concentrate are concentrated to a greater or lesser extent. In this process, the solubility limit of one or more compounds may be exceeded. In this case, the addition of antiscalant is necessary, which prevents or hinders and delays the formation of residues.