Membrane Separation Process

Membranes are used for separating two phases prevents the transportation of various chemicals in a selective manner. Separation through membrane takes place by either convection or diffusion. Transportation is affected by using electric field or by using pressure or temperature gradient. The thickness of the membrane vary from 100 rnicron to several mms. It is the application that decides the type of the membrane to be used.

Various types of liquids and gases are separated using membrane separation process. Generally speaking, membrane separation technology is used for separating following mixtures:

• Chemical compound of similar nature
• Mixture of components that are thermally unstable components

Types of Membranes Microporous Membranes Microporous membrane separates by sieving mechanism. Materials that are used for making these membranes are ceramics, graphite, metal oxides, polymers etc. The pore size of this membrane ranges between 1 nm-20 microns. Homogeneous Membranes Homogeneous membranes are dense film that use pressure, concentration or electrical potential gradient to transport molecules mixture. Asymmetric Membranes Asymmetric membrane consist of very thin layer 0.1-1.0 micron which acts as the selective membrane. Electrically Charged Membranes These membrane are used for ion exchange and consist of highly swollen gels that carries fixed positive or negative charges. Liquid Membranes These membranes are used for transporting components such as metal ions at relatively high rate across the membrane interface. For this purpose liquid membrane uses carriers.

What is Membrane Separation Technology?
In membrane separation technology feed stream into two effluent streams- the permeate and the concentrate. The stream that is rejected by the membrane is called as concentrate whereas the liquid that passes through the semi-permeable membrane is called as permeate.

Advantages of membrane separation process
Membrane separation process are applied in various industrial applications with the following advantages:

• Saves energy
• No harm to Environment
• Clean technology
• Easy operation
• Products produced by this method is of high quality
• Conventional system like like filtration, distillation, ion-exchange and chemical treatment systems can be replaced by this cost effective and environment friendly process.
• Design system can be altered as per requirement

Types of membrane separation process
There are different types of membrane separation processes that are used for various applications. Commonly used processes are:

• Reverse Osmosis
• Microfiltration System
• Ultrafiltration systems
• Nanofiltration System

Applications of Membrane separation Technology
Membrane separation processes are used for various industrial applications:

Concentration of biological molecules Concentrates gelatin Dairy industry Sea water desalination Brackish Water desalination Municipal wastewater treatment Pulp mill waste treatment Treatment of whey in dairy industry Waste treatment in chemical industry Helps in the preparation of enzyme and pharmaceutical products. Recovers electro paint

Pure water production for electronics industry In food and beverages industry for concentrating fruit juices and alcoholic beverages Concentrates biomass and separates soluble products Removes Toxins like algal ? Purifies Landfill leachate Removes Selenium from drainage water Helps in water softening Removes natural organic matter Removes heavy metals like (As, Pb), Fe, Cu, Zn etc. from water. Removes Pesticides etc.

Buying Tips
Reverse Osmosis System