An attempt is made to highlight the shortfalls when it comes to dealing with industrial pollution control in our country. This is an unbiased and non-technical article. The responsibility and awareness of the buyers and sellers alike are narrated.

The Scenario

We cannot deny that since the last two or three decades the Indian economy is booming and will continue to do so. In doing so, many have thrived in their chosen field, be it the processing industry, the equipment manufacturers, financiers, bankers or service providers.

The increased production is the essence, the production means movement and movement means dust, anywhere - in a factory, home, or hospital. In a factory of course it means a lot of dust, because so many production operations create dust, as inherent as part and parcel of that environment.

Operations such as grinding, conveying, milling, mixing, sieving, shot blasting, crushing, polishing, sanding, etc., are all processes that generate dust in great quantities and often with high proportion of fine particles.

Think of all the materials in use today: abrasives, aluminium, clay, coal, coke, copper, carbon black, cement, ceramics, composites, detergents, feldspar, fly-ash, fertilizers, gypsum, glass, graphite, iron, lead, lime, leather, mica, magnesium, paper, plastics, paint, pigments, quartz, refectories, silica, slag, soda ash, wood and zinc, to name a few. Dust generated from most of these materials is dangerous to health, toxic to wild life, as well as being in general a source of nuisance and much irritation. Even things we regard as basic to life itself, foodstuff, tea and coffee, cornstarch, flour, grain, milk powder, pharmaceuticals, salt, soap, sugar, tobacco, et al, all these in the form of uncontrolled dust can create an unacceptable health hazard or plain nuisance.

Without control, this dust would be dispersed within the factory atmosphere, and would create intolerable conditions, hostile to man and machinery alike. Without dust control, many machines and processes could not work at all, and production would come to a halt. But if the dust were confined within the factory premises, it could be prevented from blowing away to be released and dispersed into the sky. It must be controlled at source to create satisfactory and hygienic working conditions and helpimprove productivity.

When controlled, it must be collected, not discharged to create external pollution for all to see, breathe and suffer. The prospect of covering an entire neigh-bourhood with dust is not just accepted by anyone, in industry or the community alike.

Dust control today means control of dust at source and then collection for hygienic disposal for the benefit of the community at large, and the community at large does not mean only those living near the factory concerned. In fact, the need of dust control is never ending.

The Suppliers

Many dust control companies operate within India, from fabricators turning into the dust control equipment suppliers to corporate companies that apart from dust control, also straddle the whole field of air handling and air treatment. Then there are those dedicated manufacturers and suppliers whose main products and activities are pollution related; and their lively hood depends on it. The above group of suppliers work within their capacities and it is up to the buyer to select the appropriate supplier based on his or suppliers capability.

The Trends

In general, the tendency of actual buyers or their consultants is to consider the 'filtration efficiency' as a criterion of the dust collector efficiency, but in practice this is not possible. What if the fault lies in the design of equipment, the leakages or filter surface damages? The efficiency of 99.99% offered by the media supplier will be hard to achieve in such cases.Thus, unless the dust collector is required, as a direct replacement in an existing system or if it is a process requirement, the buying criteria need to be changed from 'filtration efficiency' to 'collection efficiency'.

For the purpose of complying with the legal norms the 'filtration efficiency' does matter. However the 'system efficiency' should be aimed for, which includes the 'collection efficiency' in any case.

You may ask what is the 'system efficiency'. The system efficiency is the efficiency which fulfils the ultimate goal of the buyer to his satisfaction, based on what was 'agreed during the order placement' if the legal emissions norms are involved, then it becomes the supplier's responsibility to achieve the target limits. He is to ensure that, this fact and implications are considered during the order placement.

It is up to the buyer to select a competent supplier who can shoulder the responsibility and to put forward the appropriate solution to his problem. The supplier has to guide the buyer and provide him with the alternative solution that takes account of the process requirement, the site limits, and above all the buyer's budget.

The Equipment and Supplier Competency

The composite dust collection system is to ensure that the ultimate need of an application is met in every sense. This includes the practical aspects such as ease of operation, the maintenance and above all the control of dust at source. This starts from the selection of local suction hoods to the final separation of dust and the cleaned air dispelled into atmosphere.

In almost every case, the composite system consists of various components to be designed, manufactured, supplied, installed and commissioned. In general following components, make up a composite system: (The illustration shows the basic components of a composite system)

Suction hoods, which always terminate into a 'spigot.' This is in turn connected to the suction duct, by way of a flexible pipe or rigid connection. The function of hood is to capture the dust from the source. The suction hood can be an 'over-head canopy' type, 'side-draft' type and 'slotted-type' or in modern day, it can be a 'built-in' type in the process machine itself.

Ducting is required to convey the captured dust (dirty air) from a single or multiple suction hoods to the dust collector. Once the dust is separated by the dust collector, the cleaned air is required to be conveyed to the fan set and from fan set to the chimney or to the atmosphere. Dust collector is a core component of the composite system, it has to be selected to suit the application and it may be a simple cyclone, a bag filter, a wet scrubber or any other form of separator.

The dust collector consists of the separating media or device, media cleaning mechanism, dust discharge arrangement and the motive fan set. These items need to be designed or modified to suit the individual application. In general, the standard dust collector is modified making it dedicated equipment for a given application.

Fan set is needed in every system. The function of the fan set is to provide the energy to the suction hood to capture the dust particles from the source, to overcome the friction losses in the ducting and pressure loss across the dust collector.

The design factor, the experience and actual knowledge of the application play a major role while supplying the dust collector as a part and parcel of a composite system.

The competent supplier must have design and manufacturing infrastructure of his own, the knowledge, field experience, and a large enough product or equipment range to enable him to offer alternative solutions for a given application. He must also understand his moral obligation to wards the buyer, he is the expert and not the buyer, and thus it is his duty to ensure the ultimate results are achieved.

The initial teething problems at the commissioning stages will be there, but with the co-operation of buyer it has to be amicability solved. Unless and until the supplier delivers the above, he cannot be termed as a competent supplier.

The Buyers

Who are they and what are the predicaments faced by them?
They can be categorised as:

1. Those who need a dust separator to form a part of 'process equipment' and directly attribute to the production.

2. Those who need to re-reuse the collected product, which is otherwise lost as dust.

3. Those who want to improve the working efficiency of the workers and the plant efficiency which otherwise is prone to frequent breakdown due to dust. (These comprise the major portion of buyers).

4. Those who create the pollution, but are aware of obligation to community and welfare of their workers, to them pollution control is of paramount importance. (Unfortunately they are far and few, these type of god-fearing buyers can be termed as endangered spices).

5. Those who need the dust collectors as part of their specialised product, such as the manufacturers of boilers, material handling equipment, crushing, grinding and screening equipment, the pharmaceutical equipment and the paint booth suppliers to name a few.

6. Last but not the least, those who are compelled to install the pollution control equipment to meet mandatory requirements. (This proportion of buyers is on the rise).

The Knowledge & Awareness

In the context of the above categories, the first category of buyer will be more interested to install equipment, which is of the best value for the money spent. He has no choice but to educate self or hire the consultant to select and buy the appropriate equipment.

The second and third category of buyers need to know more than the basics of the dust control equipment. They must do their homework to ascertain the ultimate need of the proposed system. They must be able to evaluate and compare the offers.

The forth category of buyers also need to know more about the dust control before spending the well intended money for the good cause, only the competent supplier should be engaged, only then their invested time, energy and money will pay back sooner than expected.

The fifth category of buyers as experts in their chosen field, they should concentrate in improving their technology and product range. They should equally understand that pollution control is also a specialised field on its own. Thus they should appoint appropriate OEM supplier on long-term basis. The tie-up of two specialist manufacturers can only serve to the benefit of all the concerned.

The sixth category of buyers are in total dilemma; to them the capital investment towards the pollution control equipment is a dead investment. They tend to install the cheapest possible equipment; hence the suppliers with half knowledge will thrive leaving the competent suppliers to fight in vain.

Within this category there is a segment of buyers, who knowingly install sub-standard showpiece equipment, for all to see and suffer. They get away because they know the ways and means, actually do find a way and means deal with the appropriate legal department to their advantage and leaving the community at large to suffer. They must learn to appreciate their responsibility towards the community requirements and have to change their attitude, sooner the better.

Our country is large, with proportionally less specialist or competent suppliers, there should be no need to have cut throat competitions, on the contrary the larger business group should pass on the smaller or non-lucrative enquires to the smaller counter parts, instead of not helping the actual user. This is may be asking for too much!!!

As a supplier of pollution control equipment, it is more than making money or larger empire; it is an industry in which we are directly or indirectly helping towards greener environment and earning our living at the same time. (I am sure we cannot find any better way to pay back our mother country).

Reference

An article written by the same author "An Industrial Dust Control System" (Criteria of buying and installation), published in the October 2010 issue of IPF, may be referred for further guidance and insight.

Raman B Patel, Technocrat, Founder Member of Anil (Air) Pollution Controllers. After obtaining in-depth training and firsthand experience in UK from Dust Control Equipment Ltd (now TORIT DCE LTD), returned to India and set up the company in the year 1976. He had further work experience in pollution control related field in UK from 1990 to 2001; during his second stay he gained firsthand experience in hot air filtration, explosive dust control and fume extraction technology. His work experience in the field of industrial dust control spans over 43 years. Email: info@anilairpollution.com