Waters with Organic Pollutants

Water pretreatment before discharge is often mandatory. Why? Because one of the conventional water treatment methods is treating water with chemicals. Used chemicals and processes often do not have an environmentally friendlier alternative. Therefore, a water pre-treatment needs to be installed.

The list of emerging contaminants is continuously expanding, and regional regulation is getting stricter by the day. Environmentally aware process design is encouraged, but more and more contaminants and their effects keep emerging. It is challenging to keep up the pace. The result is that we need more and more advanced end-of-pipe solutions as we keep learning, which often occurs in higher costs.

In contact with water, the high-speed electrons in non-thermal plasma enable the formation of OH-radicals and ozone according to the following equations:

The atomic hydrogen as a product of the first equation is prone to reacting with molecular oxygen (O2), yielding hydroperoxyl radicals (HO2) which are also oxidants.

OH-radicals and ozone are very strong oxidants. This means that they can oxidize harmful organic pollutants. Oxidation of organics in its ultimate extent results in mineralization to carbon dioxide. Usually, complete mineralization is, however, not a requirement, allowing optimization of energy input.

In Roxia Plasma Oxidizer, the water falls like rain through a large plasma volume. This enables constant flux of abundant radical oxidants that effectively destroy organic contaminants, such as pharmaceuticals, biocides, surfactants and residual active reagents.

_{Various reactive oxygen species are present in plasma liquid contact. The most important ones are hydroxyl radical and ozone.}