A multifunctional system with

3 key functions

The technology developed by COLDEP, resulting from the joint research of INSA Lyon and IFREMER, is covered by the patents N ° 07/02308 and N ° 09/57898, for which we hold the exclusive operating rights. Our Vacuum AirLift process (VALTM) combines the known principle of airlift and foaming-skimming with partial vacuum, and can combine up to 3 functions simultaneously. However, it is still quite possible to use it for just 1 or 2 of the key functions.


Hydraulic circulation

Move large volumes of water with unprecedented energy performance.

  • Without load losses external to the COLDEP column, the energy cost is around 5 W / m3 of liquid displaced.
  • With a COLDEP system it is possible to achieve flow rates of 20 to 1500 m3/ h, by combining several systems we can go much further.
  • The free passage treatment (without filter) eliminates any risk of clogging.

In the case of a low pressure drop system, the column can replace not only the usual treatment systems, but also the pumping systems: an economical all-in-one solution.


Management of dissolved gases

Increase or decrease as needed the dissolved gas content of treated water with energy performance never achieved.

Injection by bubbling gas into the treated water in the column generates numerous gas exchanges. Putting under vacuum makes it possible to significantly increase the performance of these exchanges:

  • In degassing mode, values below 30 ppb can be reached fairly quickly.
  • In gas injection mode by micro-bubbling, it is easily possible to dissolve several liters per minute without any loss.
  • The two functions can be combined to degas before injecting the replacement gas.

Particulate extraction

Separate suspended matter from water by combining the principles of adsorption and electrostatic forces with flotation governed by Stokes' law to result in the extraction of particles in the water.

The COLDEP system therefore makes it possible, with low energy consumption, to:

  • Filter seawater with a result <3 SDI in a few hours.
  • Concentrate particles suspended in water up to 100 times.
  • Do without chemical additives to achieve these results.

It is not only possible to extract more than 99 % from the particles of the water but also a majority of the dissolved organic matter as well as oils and hydrocarbons!

Discover the different parts of the system

A modular system

The 3 key processes of our technology are provided by our VAL columnTM aided by a set of peripheral equipment, thus forming the COLDEP system. This system is modular to adapt to your needs. Fully automated, programmable to operate continuously or in adjustable time periods.

Discover our system

Hover over the image and click on the green areas to learn more about each part.

Discover our system
Cuve de sécurité ou Récolteur Armoire électrique Compresseur d'air Pompe à vide Colonne à dépression (VAL™) Séparateur gravitaire Bassin

Safety tank or harvester

  • In certain cases where gravity emptying is not sufficient or impossible, a safety tank can be positioned to remove what would not have been evacuated by the gravity separator.
  • The harvester makes it possible to recover the juices of interest, which are extremely concentrated. Its automation makes it possible to precisely regulate the volume to be extracted and to plan oil changes.

Electrical cabinet

Brain of the system, including in particular the automaton making it possible to manage the whole installation.

Air compressor


In some cases, the use of a compressor makes it possible to optimize the particulate extraction function by injecting microbubbles into the VAL. It is also possible to use a booster.

Vacuum pump

Heart of the system which allows to:

  1. Keep the system under vacuum and functional as an air-lift pump process (the circulation of a volume of air is 10 times less energy intensive than that of a volume of water).
  2. Reduce the solubility of gases (Henry's law) so as to optimize gas exchange.
  3. Accentuate the phenomenon of flotation of the gaseous particles by expansion of the gases in a vacuum.

Vacuum column (VAL ™)

Reactor in which all the key functions of our system operate.

Gravity separator

Used to evacuate the concentrated foam containing all the impurities treated by the column on one side and all the gases on the other. The liquefied foam naturally empties by gravity. The volumes are variable but represent less than 1% of the treated volume since they are very concentrated



Contains water and allows its circulation thanks to its structure.

Innovative technology with

Exceptional performance



Flow rates up to 1000 m3/ h with a single vacuum pump, for a low OPEX. The simplicity of the materials used and the ease of maintenance ensure inexpensive use. The pressure drop being very low, the energy efficiency is excellent and only requires low energy consumption, most often <2 kW.


Easy to maintain

In standard operation, the system is fully automated and does not require intensive supervision. The system only requires simple maintenance spaced out over time. This simplicity allows accessibility to the product to all customers, regardless of the environment because it does not require any specialization for management.


Reliable & Durable

Simple materials are used in the design. No part is liable to wear or corrode, which allows for an exceptional service life. The free passage treatment avoids any risk of clogging. Finally, the design makes it possible to centralize the motor units outside wet areas, which further increases the reliability of the system.



The VAL columnTM is a system which has a low footprint due to its verticality. In addition, there are different sizes adaptable to the available space and really proportional to the need. This allows us to make bespoke installations even in smaller spaces.



The major capacities of the process: water circulation, particulate extraction, gas dissolution and degassing can be used in combination or separately. This allows a multitude of different applications and therefore a solution to all needs. The process can then replace a chain of systems with a single product. 

eco-light (1)


The physical process involves no additives, no consumables and does not cause any rejection in the circuit. The extracted waste is captured and retained. The extracted gases are released to the outside, therefore reducing the ventilation requirements of the installations. Finally, the efficiency of our equipment allows low energy consumption, requires little maintenance and therefore reduces the environmental footprint.