Cavitation
Area of application - water purification

Water purification

Cavitation is a pioneering solution for water treatment - thanks to its high level of environmental friendliness and compatibility with other processes. It can improve the efficiency of pollutant reduction by up to 70% - without any chemical additives.

Water purification by cavitation is based on physico-chemical processes that occur when cavitation bubbles collapse. Extremely high pressures and temperatures are generated locally, resulting in thermally degrading and oxidizing effects. The shear forces, shock waves and reactive radicals generated during cavitation have a disinfecting effect.

Integrated into water treatment plants, the RAPTECH CaviFlow® inline module offers an innovative and effective plug&play solution for sustainable water purification:

Oxidative degradation of organic pollutants and sludge treatment
Destruction of cell structures of bacteria, viruses and algae
Destabilization of emulsified oils, microplastics or colloidal particles
Cavitation-supported pre-treatment supports the efficiency of downstream processes
Increased efficiency of aeration

Typical areas of application for cavitation-based water treatment are municipal wastewater treatment plants, industrial wastewater, disinfection of process water and disinfection in swimming pools. In the oil and gas industry, cavitation is used to remove oil or treat refinery wastewater.

Advantages of water purification with CaviFlow® inline module

Cost efficiency

Effective pollutant degradation

Without chemical additives

More efficient than conventional methods

+70%

Improvement of the

Degradation of pollutants through cavitation

+30%

More efficient in comparison

to conventional methods

Areas of application

Wastewater treatment plants
Wastewater treatment plants
Industrial process and waste water
Technical process and waste water
Commercial process water and wastewater
Agricultural process water
Service and process water
Cooling and boiler water
Sludge treatment
Water recycling
Disinfection
Drinking water treatment
Raw water treatment
Municipal water companies
Swimming pools

CaviFlow® modules

Integration in water treatment plants

Cavitation in the CaviFlow® inline module uses physical effects highly efficiently, requires little infrastructure, works quickly and can be integrated in a space-saving manner - making it a particularly compact and energy-efficient solution in water treatment.

Compact reactors thanks to high reaction rates

The extreme conditions during the collapse of the cavitation bubbles lead to very fast reactions. Pollutants are attacked in fractions of a second. This allows compact reactor designs with short residence times - ideal for mobile or space-saving applications.

Utilization of existing flow energy

Particularly with hydrodynamic cavitation (e.g. with Venturi nozzles or cavitating rotors), the flow energy of the system can be utilized or provided by existing pumps. Compared to other Advanced Oxidation Processes (AOPs), the specific energy requirement is low.

Scalability and modularity

Cavitation systems are modular and can be easily scaled up to large-scale applications. Simple integration into existing piping systems minimizes space requirements.

CaviFlow® modules

Integration in water treatment plants

Extreme physical conditions

The CaviFlow® inline module is particularly effective at breaking down pollutants during water purification because the collapse of the cavitation bubbles generates temperatures of up to 5,000 °C, pressures of several hundred bar, shock waves and strong micro-turbulence. These extreme physical conditions trigger highly reactive processes - directly in the water.

Formation of highly reactive species (radicals)

The thermal decomposition of water (H₂O) and oxygen during cavitation collapse also produces chemical radicals such as hydroxyl radicals (OH), hydrogen peroxide (H₂O₂), superoxide anions (O₂) and ozone (O₃). These radicals are extremely reactive and attack pollutants immediately - they split C-H, C=C and other organic bonds into smaller, often harmless molecules.

Simultaneous physical and chemical attacks

In addition to chemical attacks by radicals, ultra-fast mixing with shear forces and microjets, which destroy the cell walls of microorganisms, and shock waves, which break up particles, emulsions or biofilms, also have an effect. This combination ensures that pollutants are not only chemically degraded, but also physically destabilized or desorbed.

CaviFlow® modules

Integration in water treatment plants

Cavitation with the CaviFlow® inline module improves aeration efficiency in water treatment. Due to the high dynamics in the cavitation field, the contact between air (or pure oxygen) and water is significantly intensified. Compared to existing aeration systems, the energy requirement can be reduced while maintaining the same performance - a major advantage, especially for energy-intensive processes.

Increased oxygen transfer rate through micro gas bubbles

The collapse of cavitation bubbles produces secondary bubbles that are significantly smaller than conventionally injected air bubbles. They have a larger specific surface area, rise more slowly, i.e. they stay longer and dissolve more efficiently in the water. This leads to a significantly improved oxygen input compared to coarse-bubble aeration systems.

Intensive mixing at micro level

Cavitation generates strong micro-turbulence and shear forces that promote an even distribution of oxygen throughout the reactor. The microorganisms in the activated sludge are thus better supplied and require proportionally less oxygen for the same degradation effect. This further optimizes oxygen consumption.

Reduction of the total energy requirement

As the oxygen input per unit of energy increases, the required blower output (e.g. for compressed air) can be reduced or existing ventilation systems can be operated more efficiently. In many applications, the specific energy requirement (kWh/kg O₂) decreases significantly.

CaviFlow® modules

Integration in water treatment plants

Cavitation with the CaviFlow® inline module works without any chemical additives. It generates oxidative agents directly in the water, e.g. hydroxyl radicals, without having to dose external chemicals such as ozone, chlorine or hydrogen peroxide. There is also no need for storage tanks, dosing stations and safety infrastructure, which saves space and energy. Only in special cases - e.g. with substances that are very difficult to degrade or for process optimization - can a targeted combination with small quantities of reagents be useful. This keeps the process as a whole resource-saving, environmentally friendly and economical.

No rebound effect or problematic degradation products

In contrast to some chemical processes (e.g. chlorination), cavitation also produces no by-products that are difficult to control. The reaction usually results in harmless end products such as CO₂, H₂O or smaller, biodegradable molecules.

CaviFlow® modules

Integration in water treatment plants

Cavitation with the CaviFlow® inline module increases the efficiency of biological or physico-chemical purification stages, which means that downstream aeration or filtration, for example, requires less energy. The dosing of additives can also be reduced or avoided altogether. In addition, cavitation can be operated as a continuous process. This enables constant and controlled pollutant reduction - even with varying feed concentrations.

Plug & Play with CaviFlow®

RAPTECH cavitation technology can be easily implemented as part of secondary treatment in water treatment systems using the CaviFlow® inline modules developed in-house - and without high investment costs. CaviFlow® modules are suitable for integration in any section between aeration and disinfection.

CaviFlow® | Immediate use

The CaviFlow® inline modules are plug & play and easy-to-clean and can be quickly implemented in existing wastewater treatment plants. Equipped with a flange or threaded connection, they can be used immediately. The modules remain effective even when used for wastewater containing impurities and organic solvents. This is because there are no moving parts inside them.