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close this bookEnvironmental Handbook Volume II: Agriculture, Mining/Energy, Trade/Industry (GTZ/BMZ, 1995, 736 pages)
close this folderTrade and industry
close this folder48. Glass
View the document1. Scope
View the document2. Environmental impacts and protective measures
View the document3. Notes on the analysis and evaluation of environmental impacts
View the document4. Interaction with other sectors
View the document5. Summary assessment of environmental relevance
View the document6. References

5. Summary assessment of environmental relevance

The effects of glass works on the environment and workplace are caused by noise, dust, effluent and flue gases.

Table 6 - Environmental impact of process stages (glass)

Process Air Noise Water Soil Work- place
Waste gas/ Flue gas Dust1)
Dressing
Melting
Moulding
Cooling
Sorting
Packing
Machining/Refining
1
3
2
2
1
1
1
2
3
1
1
1
1
2
2
3
4
3
2
2
2
1
3
2
1
1
1
3
2
3
3
2
1
1
1
2
3
4
2
1
1
2

Key: 1 very slight; 2 slight; 3 moderate; 4 considerable

In some cases technological and processing developments and improvements have already been implemented, e.g.:

- Arsenic and tellurium are now only used as refining agents in exceptional cases.
- Fluorspar is no longer used as a flux.
- The specific outputs of the tanks have been increased with a simultaneous reduction in energy consumption.
- Wastewater circuits have been introduced.
- Numerous noise protection devices have been installed.
- Wet, electric and dry sorption plants have been installed for dust extraction.
- Tank designs and fire management systems have been improved.

Many of the processes so far tested in individual cases are capable of further technical improvement and more economic design, paying particular attention to environmental regulations. The expected costs of environmental protection devices and measures may be as much as 20% of the total investment costs of a glass works.

Proper maintenance is essential to environmentally acceptable operation of the plants. Suitable training must be given and personnel generally made aware of environmental concerns.

Early involvement of neighbouring population groups in the planning and decision-making processes will enable measures to be devised to deal with any problems arising.

In countries which have no legal guidelines it should be ascertained as early as the planning stage, based on the raw materials to be used and the process technology applied, what environmental protection measures are necessary and appropriate. Environmental protection equipment provided should be of robust design so that the life of this equipment is appropriate to the overall project and so that simple, low-cost maintenance can be guaranteed.