What are multiphase systems ?
A multiphase system is composed of a large number of small objects (solid particles, liquid droplets, gas bubbles) called the “dispersed phase” surrounded by a “continuous phase” (liquid or gas in most cases). The table below shows some examples of multiphase systems encountered in industry.
Multiphase systems are very attractive because of the large area [m²] of the interface between the suspending fluid and all the small objects. This high area is a key advantage in thermal, chemical and physical phenomena because it leads to increased heat and mass transfer rates from one phase to another. The benefits are multiple: processes can run faster (smaller OPEX), in smaller reactors (smaller CAPEX) and with a greater spatial homogeneity (better product quality).
As an illustration, the list below shows examples of industrial processes involving multiphase systems and which demonstrates the high attractiveness of our EMJM to the industrial sector:
- Fossil fuels: a fluidized bed with solid catalyst particles used to crack oil in light compounds like ethylene, gasoline,
diesel, ... - Polymers: a fluidized bed for producing polyethylene particles later extruded
- Biotechnology: biomass particles injected with air in a combustion chamber to generate heat or in a gasification unit
to generate syngas later converted to liquid biofuel - H2 production: H2 bubbles generated in an electrolyser
- CO2 capture: packed bed columns with a falling amine liquid film used to absorb gas
- Cement industry: concrete is a mixture of particles and additives in water that undergo hydration reaction
- Hydrometallurgy: extraction of metals contained needs crushing ore in small particles, transport and mixing with liquid
water for separation (flotation or leaching, dissolution-recrystallization) - Healthcare, pharmaceutics: most tablets produced from solid particles synthesized by crystallization
- Detergent: washing powder for clothes
- Food industry: a lot of particles: soup or coffee powder, sugar, flour, cereals, ...
- Electricity production: boilers heated by solar energy, geotherm, fission or combustion generate steam from liquid to
entrain a turbogenerator (bubbles in water) - …