Reverse Osmosis

WASTE AND ENVIRONMENTAL MANAGEMENT IN PETROCHEMICAL INDUSTRIES

CPE 681

MEMBRANE APPLICATION: REVERSE OSMOSIS, MICROFILTRATION AND ELECTRO

DIALYSISGROUP MEMBERS:

NURUL FAHADA BINTI SAARI 2011278488ANIS FARHANAH BINTI MOHD SUHAIMI YEONG 2011635218MUHAMMAD AFIQ BIN MOHD HAFEEZ 2011814658

INTRODUCTION1. Pressure-driven operations• Microfiltration• Ultrafiltration• Nanofiltration• Reverse osmosis

2. Concentration-driven operations• Dialysis• Pervaporation• Forward osmosis• Artificial lung• Gas separation

3. Operations in electric potential gradient• Electrodialysis• Membrane electrolysis• Electrodeionization• Electrofiltration• Fuel cell4. Operations in temperature gradient• Membrane distillation

Membrane Distillation

Membrane Materials

Commonly used membrane : Polymers Metal membrane Ceramic membranes (metal oxide, carbon, glass) Liquid membranes

Microfiltration

A type of physical filtration process A contaminated fluid is passed through a special pore-

sized membrane To separate microorganisms and suspend particles from

the process

Electrodialysis

Electrodialysis is a separation process using a stack of alternating anion- and cation-selective membranes separated by spacer sheets.

Water is passed through the stack of membranes. Electrical current is applied to the cell, causing the anions

to migrate in one direction and the cations in the other direction.

Reverse Osmosis

Water purification technology that uses a semipermeable membrane to remove larger particles from drinking water.

An applied pressure is used to overcome osmotic pressure. Hence, called the reverse osmosis.

How it works?

Membrane Process Characteristics

Reverse Osmosis

Reverse Osmosis

Exert hydraulic pressure which more than the osmotic pressure (natural diffusion of water)

Diffusion of water into less concentrated section, left the particles behind. http://www.geafiltration.com/technology/reverse_osmosis_flash.as

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Microfiltration

Nanofiltration

Ultrafiltration Microfiltration

Its like “sieve” membrane filtration and differs on its pore size

Electrodialysis

Ions are transported through semipermeable membranes under the influence of an electric field

Two different solution generated in this process One dilute and other concentrate

Electrodialysis (cont’)

Differences in Properties  Properties

  Reverse Osmosis Microfiltration Electro dialysisPore Size <0.0001 0.01-1.0 <10

Molecular Weight Cutoff 100-300 >100,000 -

Operating Pressure 225-1000 psi <30 psi Electrical potential

Membrane Materials Cellulose acetate, thin film composite, polysulfonated polysulfone.

Ceramics, polypropylene, polysulfone, polyvinylidenediflouride.

Membrane made of cation or anion selective matter.

Membrane Configuration Tubular, spiral wound, plate and frame.

Tubular, hollow fiber. Multiple membrane in a row which have alternate configuration to allow positively or negatively charged ion to flow through.

Types of material removed Metal cations, acids, sugars aqueous salts, amino acids, monovalent salts, BOD, COD.

Clay, bacteria, viruses, suspended solids.

Removal of ion from wastewater.

Electro dialysis vs ElectrolysisElectro dialysis Electrolysis-Use ion permeable membrane to separate between two charged plates of the ionization chamber.-anode and cathode plates are in separate compartments.-Acidic water and alkaline water is separated.

-Anode and cathode are in the same chamber.-the alkaline water from cathode plate and acidic water from anode plate are not separated.

Microfiltration vs Ultrafiltration vs Nano filtration

Microfiltration Ultrafiltration Nano filtration-Served as pre-treatment for other separation process such as ultrafiltration.-To prevent particle such as sediment, algae, protozoa or large bacteria.

-Use for pretreatment of water for nano filtration or reverse osmosis.

-Technique use to remove two valued ion and larger mono valued ions.

Reverse Osmosis vs Forward Osmosis

Reverse Osmosis Forward Osmosis-Require pressure to push water into semi permeable membrane to remove large majority of contaminant.

-Does not require external pressure to push solution through membrane.-Water diffuses spontaneously from low osmotic pressure solution to solution with high osmotic pressure.

ApplicationsTypes of membrane ApplicationReverse Osmosis -Treatment for industrial

wastewater-Drinking water-Desalination

Microfiltration -Pharmaceutical process.-Oil purification-Regenerate based oil from used oil.

Electro dialysis -Separation of inorganic and organic solutions.-Wine stabilization-Purifications of salty mine waters

Forward Osmosis -Waste water treatment-Food processing-Water desalination