Distillation

Pure and safe drinking water is a necessity. The purity of water is closely related to the safety of health. Distillation is one of the effective and the oldest method for obtaining pure water for consumption. Water as we know contains large amount of pathogens and other particles that cannot be viewed by the human eyes but if they enter the human body they can prove determental to their health. It is therefore necessary that water is treated and purified before it is consumed.

Process
Distillation Process can be applied to address both large scale and small scale water contamination situation. In distillation process, water to be treated is heated and evaporated. The steam of the water is collected and then condensed to obtain pure water. The principle behind this is that the water evaporates but the inorganic waste and large non volatile organic compound and molecules do not. Hence when the water is boiled these organic compound are left behind.


Impurity Removal
Through distillation process, inorganic compounds like metals(iron and lead), nitrates, water hardening compounds like calcium and magnesium and particulates are removed effectively. As the process involves boiling, bacteria and viruses also get destroyed. The removal of organic compound from the wastewater depends largely on the characteristics of the organic compounds like solubility and the boiling point. There are some organic compounds that has higher boiling point than water. In such case organic compounds are removed easily. However in some cases the boiling point of Organic compound is less than water will be vaporized along with water. Hence it is necessary that these compounds are removed before condensation otherwise they will recontaminate the pure product.

Distillation Units
A typical distillation unit consists of water collection chamber in which the infeed water is collected. From here water is transferred to the boiling chamber where it boils and evaporates. The vapor is finally condensed in a condensing chamber where water is cooled and collected in separate chamber. The product water so collected is free from any contamination. Depending on the size of operation the water distillation capacity and size may vary.

Type of Distillation Process
There are different types of distillation process. Some of the distillation process that are commonly used are:

• Multistage Flash (MSF) Distillation
• Multiple Effect Distillation
• Vapour Compression Distillation

Applications of Distillation Process
The distillation process is used in various industries to obtain pure water. The industries they serve are:

• Semi conductor and electronic industry
• Municipal water treatment
• Seawater Desalination
• Brackish water treatment
• Brewery Industry
• Distilleries
• Food processing industry etc.