Economy is demanding progress and one of the routes to progress is industrial expansion. Rise and expansion of industries raises a major concern that is industrial pollution. This kind of pollution occurs when manufacturing units release harmful waste like untreated water, chemicals, gases etc. into environment.

Beginning of 21^st century marked the advent of industrial revolution and technological advancement at more rapid pace, with which came greater exposure to science and manufacturing age entered into focus. Earlier industries assumed the form of small scale factories which were not that big of a polluting agent. But expansion lead to significant rise in large scale manufacturing units, and this is when problem of pollution became highly noticeable and worth paying a strict attention. Three types of waste that are discharged by factories into environment are industrial effluents, waste and residue. These wastes are normally released into air, water and soil thus creating three major forms of pollution namely air, water and soil pollution.

Manufacturing processes release much harmful stuff which is a cause of environmental degradation. It is major reason for ecological imbalances, natural resource depletion and raises health concerns for humans. In developing countries focus is not given to the concern which is an after effect of much needed industrialization. Environmental standards are often inappropriate and pollution control techniques are not fully developed. Other than these, small scale industries which are rapidly proliferating in towns and villages, due to their lack of knowledge and funds, are contributing even more towards polluting activities. Contamination of air in developing countries is ramification of large scale industries like iron and steel, non-ferrous metals, petroleum products etc. and some small factories eg. Cement mills, lead refineries, chemical fertilizers and pesticides factories etc. Water and soil pollution is caused by uncontrolled discharge of waste material onto land and into water.

Release of waste and effluents:

• into air have led to ozone depletion
• into water has led to contamination of water
• and onto land have lowered the quality of soil

Causes:

1. Proper policies to control the problem lacked in numbers and were inefficient
2. Industrial growth was highly unplanned within townships, and companies defied the policies and laws
3. Technologies used by production units were outdated. This was to avoid the high cost and expenditure.
4. Small scale units were increasing and it was costly for them to rely on government grants, abide by the laws and to employ new techniques of control.  
5. Waste disposal techniques were ineffective which led to evolution of chronic health problems.
6. Natural resources were leaching away. Lands were cleared away for the construction of factories and there was excessive mineral extraction.

Companies in their efforts to fight against this problem have come up a solution to deploy filters. Filtration as a process is used to separate solids from fluids (liquids or gases). They are used in almost all the production processes these days and thus their use is becoming a common phenomenon. There usage is restricted not just to purification of air or water. They are also used for oil, clothes, feed pumps and various other materials. For example production of biodiesel follows the process of waste vegetable oil filtration by using waste vegetable oil (WVO) filters. The process of purification makes use of micron filter bags. Bio diesel can substitute petroleum in future and is an ecofriendly product.

Use of a filter can also prolong the life of your machine and add to its efficiency. There is slight possibility that very few manufacturers may not be knowing this. But those who know sometimes don’t lay much stress on their use for the machines pertaining to budget constraints and cost cutting.

Filtration process is employed by many manufacturing and processing units to remove many different types of impurities. For this many different of industrial filters or filter presses are required. They are:

1. Air Filters

   Also known as Air Intake Elements or Fan filter they are used to separate dirt from the air. Fitted with polypropylene mesh screen they are most extensively used.

2. High Efficiency Particulate Air Filters:

   They are required in tougher processes where air filter may not perform efficiently. They are designed on purpose by Atomic Energy Commission.

3. Bag Filters:

   They are used to separate solid particles from liquid and are preferred to remove solid chunks from ink coolant paint etc.

4. Hydraulic Filters:

   Requirements extend to distillation of petroleum fluids and also to purify water. They are generally cylinder shaped with tiny holes along their side.

5. Panel Filters:

They are used in ventilation system and air conditioning.

 Filter types used in different filtration process make use of micron rated filter bags. Micron ratings are given according to purification efficiency between 1 to 200 microns, eg. for 80%efficiency they are rated at 50 microns. Filterprofilters provide wide range wide range of polyester micron rated bags ranging between 1 to 200 microns.

Industrial processes rely on many different processes each on playing a significant role. Filtration is one of them which eliminates unwanted particles from water m any other substances. The process differs from plant to plant and so does its requirements.