FREECOLD Process: Thermochemical Cooling
Refrigeration from waste or durable heat recovery through the COLDINNOV process
COLDINNOV is developing a patented breakthrough innovation in sustainable cold production. Our thermochemical solid / gas process uses waste heat as a primary source of energy to produce cooling. This technology is based on the adsorption of ammonia by a solid reagent developed by COLDINNOV, in a reactor
The cold production cycle
The COLDINNOV thermochemical cooling process takes place in 4 distinct phases:
- 1 – Evaporation: Liquid ammonia from the tank is depressurized, then enters the evaporator where it vaporizes while producing cold.
- 2 – Adsorption: The gaseous ammonia is adsorbed by the COLDINNOV reagent inside the reactor.
- 3 and 4 – Desorption: Heating the reactor using waste or renewable heat releases the ammonia in gaseous form. The pressure increases and expels the ammonia from the reactor to the condenser.
- 5 – Condensation: The ammonia is condensed and then returns to the tank in liquid form.
And the cycle starts again!
The evaporation and condensation phases are similar to those of compression technologies, only the coolant changes. Indeed, our innovation concerns the reactor, which eliminates the energy-intensive and noisy compressor.
The combination of several reactors in parallel, therefore makes it possible to continuously produce both positive and negative cold.
The assets of thermochemical cooling by COLDINNOV
Our technology has many advantages over its compression competitors, including:
- Uses a source of energy valuing fatal and renewable heats
- Saves more than 80% of energy compared to a compression system
- Positive or negative cold production right from the start
- Uses a natural refrigerant with no impact on climate change or the ozone layer
- Reduces maintenance costs due to the absence of moving parts in the reactor
- Allows for the direct conversion of heat into cold or for its chemical storage
A technology adapted to various fields of application
The COLDINNOV system can be integrated wherever there is a source of heat to be exploited, both in static cooling and mobile refrigeration applications. In particular, we aim at developping our process for:
- industry: industrial process cooling, air conditioning …
- agriculture: valorization of the heat resulting from the cogeneration of biogas …
- tertiary: datacenter cooling …
- refrigerated transport by road, rail or sea
The different applications envisaged vary by their cooling capacity and therefore by their sizing, while based on a similar technology and architecture. The developments led by COLDINNOV are therefore common to all applications. This versatility is a major asset of our solution!
Besides this, the COLDINNOV solution can be used:
- As a replacement for an existing refrigeration plant
- To complete an existing cooling system
- As part of a new refrigeration system
To operate in optimal conditions, our technology requires a heat source close to 100-110 °C, commonly found in many facilities. For cases where this condition is not met, we can also consider raising the temperature by using an energy efficient gas burner. This solution allows us to use even lower temperature heat sources.
Several products to answer your needs
During the development of our technology, we have designed two types of reactors, each corresponding to a specific need:
Producing sustainable cooling: HECO/C reactor
Designed as an actual heat/cold converter, the HECO/C reactor benefits from the latest COLDINNOV advances. Its features include:
- High power density
- A very small amount of cycled ammonia
- Modular and easily industrializable architecture
- Low operating costs
Storing a refrigerating potential: HECO/S reactor
This reactor has the capacity to store the adsorbed ammonia and release it slowly, thus allowing to spread the cold production over a longer period. Due to this mode of operation, its power density nonetheless is lower than that of the HECO/C.
Ammonia, a coolant with a promising future
Ammonia (NH3) is used in the COLDINNOV thermochemical cooling products because of its important assets:
- It has no effect on the ozone layer or on global warming, unlike HFC and HCFC fluids subject to increasingly stringent regulations
- It is the fluid that allows the best performance in cold production
- Its low cost makes it competitive for large cooling powers.
Its strong corrosive power, however, makes the compressor systems complex and expensive when one wants to guarantee their tightness and their performances.
As the COLDINNOV process does not use moving parts, the corrosive power of ammonia is therefore controlled and the safety of the installation is ensured.
Common confusion: adsorption vs absorption
Our technology is based on a process of ammonia aDsorption, not aBsorption. You will have noticed, only one letter changes! However, the process is not the same and the implementation constraints either.
The absorption cycle takes place in liquid phase. The refrigerant is thus dissolved in the absorbent. Today we distinguish two main technologies:
- Water / NH3, ammonia being the refrigerant, and water the absorbent. It produces both positive and negative cooling.
- Water / LiBr, water serving as a refrigerant, lithium bromide as an absorbent. This only produces positive cooling.
On the contrary, the COLDINNOV thermochemical cooling process involves adsorption. The reagent used is thus solid. This is why it is also referred to as a solid / gas thermochemical reaction. As we are using ammonia, the cold produced can both be positive and negative. The use of a solid and chemically neutral reagent also makes it possible to avoid the disadvantages of a liquid absorbent, which can lead to leakage and corrosion.