Pam in the Media

CHARACTERISTICS OF HOLLOW ULTRAFILTRATION FIBERS:

a) Membranes with a cylindrical geometry, of the hollow-fiber type (Figure 1);

b) Material of the hollow fibers: poly(ether sulfone);

c) Outer diameter of the fibers: between 0.8 and 0.9 mm;

d) Fibers with a selective outer layer;

e) UF fibers exhibit 95.0% effective retention for compounds with a molecular weight greater than 50 kDa;

f) Filtration occurs from the outside to the inside of the fibers;

g) The ultrafiltrated extract flows through the interior of the fibers;

h) Module construction material: weldable PVC;

i) Operating pressure: depends on the extract to be processed in the equipment. The critical pressure for each type of extract must be determined;

j) Maximum operating pressure: 5 bar;

l) Maximum operating temperature: up to 55.0°C;

m) pH: 2.0 to 13.0.

CHARACTERISTICS OF HOLLOW MICROFILTRATION FIBERS:

a) Membranes with a cylindrical geometry, of the hollow-fiber type;

b) Material of the hollow fibers: poly(imide);

c) Outer diameter of the fibers: between 0.9 and 1.0 mm;

d) Fibers with a selective outer layer;

e) Average pore size on the outer surface of the fibers: 0.4 µm (Figure 1);

f) Retention of 99.99% of the microorganisms and suspended solids present in the extract to be processed;

g) Filtration occurs from the outside to the inside of the fibers;

h) The microfiltrate flows through the interior of the fibers;

i) Operating pressure: dependent on the stream to be processed by the equipment. The critical pressure for each type of feed stream must be determined;

j) Maximum operating pressure: 5 bar;

l) Maximum operating temperature: up to 55.0°C;

m) pH: 2.0 to 13.0.

≋ Diaphragm Contactors

Devices that use a membrane to create a large contact area between two phases (gas-liquid) without allowing them to disperse.

How It Works

One phase flows through one side of the membrane and the other through the other side. Mass transfer occurs through the pores without the phases mixing.

Typical Applications

Water degassing (removal of O2 and CO2), carbonation of beverages, liquid-liquid extraction without emulsification.

Advantages

• ✅ Compact system
• ✅ Precise operational control
• ✅ High mass transfer area
• ✅ No risk of flooding or emulsification

≋ Pervaporation

A process for separating liquid mixtures in which the permeate is removed as vapor; effective for azeotropic mixtures.

How It Works

A component preferentially permeates through the membrane and evaporates on the permeate side, which is maintained under vacuum.

Typical Applications

Solvent dehydration (ethanol, isopropanol), removal of volatile organic compounds (VOCs) from water, separation of organic-organic mixtures.

Advantages

• ✅High selectivity
• ✅ Does not add contaminants
• ✅Energy savings vs. distillation
• ✅ Continuous process

≋ Reverse Osmosis (RO)

The process with the highest rejection capacity. It removes virtually all dissolved salts and contaminants, producing water of the highest purity.

How It Works

It applies pressure greater than the solution's osmotic pressure, forcing water to pass through the membrane in the opposite direction of the natural flow, leaving the salts behind.

Typical Applications

Seawater desalination, production of ultrapure water for industries (pharmaceutical, semiconductor), and purification of water for consumption.

Advantages

•   Exceptional water quality
•   Proven and reliable technology
•   Salt rejection rate exceeding 99%
•   Removal of all contaminants

≋ Nanofiltration (NF)

An intermediate process between UF and reverse osmosis, with pore sizes ranging from 1 to 10 nanometers. It removes multivalent ions (hardness) and low-molecular-weight organic molecules.

How It Works

It operates at higher pressures than UF. It separates components based on size and electric charge, allowing monovalent ions to pass through.

Typical Applications

Water softening, partial desalination, pesticide removal, wastewater recycling.

Advantages

•   Lower energy consumption than RO
•   Preserves minerals (monovalent ions)
•   High rejection of divalent ions
•   Wide range of applications

≋ Ultrafiltration (UF)

Similar to microfiltration, but with smaller pores (0.01 to 0.1 micrometer), capable of retaining viruses and macromolecules such as proteins.

How It Works

It uses hydrostatic pressure to force the solvent through the membrane, while high-molecular-weight solutes are retained.

Typical Applications

• Dairy industry (protein concentration)
• Drinking Water Treatment
• Pre-treatment for reverse osmosis
• Dye Recovery

Advantages

• Virus Removal
• Operation at low temperatures
• Excellent permeate quality
• High selectivity

Microfiltration (MF)

A membrane separation process that removes suspended particles, bacteria, and colloidal solids in the range of 0.1 to 10 micrometers. It operates at low pressures.

How It Works

Water or a fluid is forced to pass through a microporous membrane. Particles larger than the pores are retained on the surface of the membrane.

Typical Applications

• Clarification of Juices and Wines
• Wastewater Treatment (Pre-treatment for RO)
• Cold Sterilization of Pharmaceutical Products
• Separation of oil-in-water emulsions

Advantages

✅ High flow rate

✅ Low energy consumption

✅ Effective removal of bacteria

✅ Easy to use