Equipment based on membranes
Membrane technology is commonly employed in advanced separation processes. The use of semipermeable membranes allows the generation of two streams: retentate and permeate.
APRIA Systems designs and supplies, based on customer demands, membrane separation facilities, as single stage or integrated in hybrid processes, addressing a wide range of applications.
The main advantages of this technology are:
Membrane-based processes are commonly applied to achieve an environmental improvement (treatment/reuse of complex wastewaters) or directly at industrial processes (valorization of secondary streams).
MF process is very similar to “conventional” filtration. It is commonly applied as a stage for clarification, cleaning or concentration since it allows the separation of colloids, suspended particles, bacteria and viruses. These membranes present a pore size of 0.1-10 µm.
Most common applications: beverage sterilization, removal of bacteria in water, separation of water-oil emulsions, separation of solids in pharmaceuticals, water pretreatment for subsequent more selective processes.
UF retains contaminants as small as proteins, viruses or antibiotics, using ultrafiltration membranes capable of retaining particles of 0.001 - 0.1 μm.
Most common applications: food industry (concentration of juices, clarification of wine and other beverages, etc.), dairy sector (recovery/concentration of milk and its serum), paint treatment (textile and metal industry), removal of trihalomethanes from wastewater.
NF retains molecules of low molecular weight and multivalent ions, with a size of 0.1 nm-0.001 μm, allowing the permeation of monovalent ions.
Most common applications: operations of demineralization, desalination and removal of color and heavy metals, wastewater treatment, nitrate removal.
Reverse Osmosis (RO)
RO retains small molecular weight molecules, concentrating solids dissolved or in suspension. This requires a pressure driving force between 15-60 bar.
Most common applications: water desalination, dehydration/concentration of food, final treatment of liquid effluents, cleaning water for electronic systems and glass industry, boiler feed water and steam systems.
Liquid Membranes (LM)
LM is recognized as an effective method of selective separation. The technology consists of a liquid phase that separates two immiscible fluid phases, allowing selective transport from one phase to another. The driving force that governs the transport of matter in this process is the chemical potential gradient, which normally results in a difference in the concentrations between the two phases (feed and re-extractor).
Most common applications: removal/recovery of metals in liquid effluents, separation of gases with similar properties, treatment of residual streams.
Forward Osmosis (FO) and Pressure Retarded Osmosis (PRO)
APRIA Systems applies cutting-edge technology to FO-PRO processes to foster synergies between osmotic pressure as a driving force and membrane selectivity. These technologies are being developed for the production of clean water, the concentration of process streams from waste streams, the removal of highly toxic substances (i.e. arsenic) from aqueous streams, as well as for the generation of energy.
The know-how of APRIA Systems allows to offer completely customizable modules, including the design and mechanization of the geometry necessary to give rise to the desired fluid dynamics, being able to operate in different configurations, including:
- Forward osmosis (FO).
- Pressure retarded osmosis (PRO).
Most common applications: wastewater treatment and water purification, seawater desalination, energy production, food processing, operations in the pharmaceutical industry.
Membrane distillation (MD)
APRIA Systems applies cutting-edge MD technology to promote synergies between thermal energy and membrane selectivity. The MD equipment design made by APRIA Systems is completely customizable, allowing to work under different configurations, including:
- Direct Contact Membrane Distillation (DCMD).
- Air Gap Membrane Distillation (AGMD).
Most common applications: water purification, desalination, water treatment in textile industry, concentration of juices and dairy products, concentration of acids and corrosive substances.
Pervaporation is a separation process used on liquid mixtures of miscible compounds (generally azeotropes and mixtures whose boiling point are very close). On one side of the membrane flows the liquid mixture, and on the other, a vacuum is applied, which causes one of the fluids to go through the membrane and pass to the vapour phase. This vapour is then condensed to finally obtain two separated liquid streams. The energy input required is much lower than in distillation operations.
Most common applications: dehydration of alcohols, removal of volatile organic compounds (VOCs) from contaminated water.
Gas permeation (GP)
GP technology is used for the separation of compounds, including pollutants and added-value products, in the gas phase.
Most common applications: treatment of gaseous effluents (VOCs), separation of gases (i.e. nitrogen or oxygen from the air), air dehydration, separation of hydrogen from ammonia, CO2 recovery.
ED applies a continuous electric field on two electrodes immersed in the effluent to be treated, allowing the separation of dissolved ionized substances in the solution by the use of ion exchange selective membranes.
Most common applications: brackish water desalination, water purification, demineralization of serum, wines and sugars, recovery of acids and bases of acidic effluents, recovery of metals.