ENVIRONMENTAL PROTECTION

Cleaner Production Technologies

Cleaner production means minimizing the environmental impact caused by manufacturing processes emissions. The design philosophy is to prevent wastes generation instead of their treatment. All process steps have to be optimized in order to minimize the waste streams.

In order of preference, the basic options to reach such design philosophy can be summarized as:

a- Source reduction: the most effective way to prevent a particular product entering the environment is to interrupt its use or manufacture;
b- Product modification: we should operate a particular manufacturing process only if the product fabricated in this process cannot be made in a cleaner way. Alternative products may perform the same function with minor environmental consequences;
c- Technology change: a particular process should be designed or modified in such a way that potentially polluting products are not manufactured or stored, minimizing the likelihood of undesirable environmental emissions;
d- Reuse: product reuse is an alternative way to prevent its emission to the environment;
e- On-site recycling: using given manufacturing process waste or byproduct as raw material to another process, we are disposing this waste or byproduct without any environmental impact;
f- Off-Site recycling: send given manufacturing process waste or byproduct to be used as raw material to another process in another site, is similar to on-site recycling, but eventual polluting load and handling, transportation and other costs make them less desirable.

If the production of a polluting agent cannot be prevented, we shall provide its adequate final disposal or treatment. This, obviously, could not be deemed as cleaner production. Only after exploring completely the above-described options we should search for the most appropriate methods to deal with those waste streams one cannot eliminate.

To achieve a cleaner production technology we need good engineering projects, good management practices and innovative process concepts. The cleaner production technology at issue will depend on the process or industrial sector concerned. For example, water conservation and energy management may be the main concerns to a soft drinks manufacturer, while to a chemical company, the raw materials control and the production route may be more important. This way, cleaner production is the most effective process, ensuring maximum utilization of all raw materials. Since cleaner production refers to innovative ideas to the processes and to the adequate management of people and facilities, it is not necessarily a more expensive technology. Cleaner processes can be operated by any organization, no matter the size and the kind of the operation. For many processes, the main facilities for a cleaner production already exist. We need only introduce the necessary modifications or establish new procedures.

The advantage of using a cleaner production technology is both environmental and financial. Designing a process to minimize waste streams, the efficiency will be usually higher. Sometimes the additional implementation costs are counterbalanced by the process higher efficiency, but when waste disposal costs are taken into account, cleaner processes are, by themselves, more cost-effective.

Organic solvents, which are responsible for volatile organic compounds (VOCs) emissions, are widely used in the paints production and application. Paint manufacturers have then developed water-based paints, which does not contain organic solvents. This is an example of product modification (substitution). Some of these paints still have a more expensive composition. However, the production process will be safer, since it does not involve flammable compounds; as well as there will be no need for organic vapours abatement equipment.