Civil Engineering Reference
In-Depth Information
chance that impurities can evaporate into the air, such as the heavy metals
nickel, thalium and cadmium. The environment is usually exposed to large
amounts of dust of different types and colours.
Pollution due to the production of base materials
Material
Potential pollution
Calcined lime
SO 2 , CO 2 , unspecified dust
Natural gypsum
SO 2
Portland cement
SO 2 , PAH, NO x , Tl, Ni, quartz dust, unspecified dust
Glass
SO 2 , CaCl, CO 2 , unspecified dust
Many forms of silica dioxide (SiO 2 ), have to be seen as risks for the working cli-
mate. The problem is dust from quartz; overexposure to quartz can lead to sili-
cosis. Dust from quartz can be emitted from several sources such as bricks con-
taining quartz, or the production of stone, cement, concrete, rockwool, glass,
glass wool, ceiling paper (where the paper is coated with grains of quartz), paint,
plastics and glue. Olivine sand is not dangerous and can be used instead of
quartz sand at foundries. Quartz sand can be replaced by materials such as per-
lite and dolomite as a filling for plastics. Silica dioxide dusts in the form of fossil
meal and perlite are amorphous compounds and harmless apart from an irri-
tatant effect.
Primary use of energy for the production of base materials
Material
MJ/kg
Temperature (°C)
Calcined lime
4.5
900-1100
Calcined natural gypsum
1.4
200
Portland cement
4.0
1400-1500
Glass from raw materials
10.0
1400
Glass, 50% recycled
7.0
1200
(varies according to the type of
glass and its purity)
When producing cements and lime binders workers are exposed to many dif-
ferent risks, depending upon the type of product, such as the heavy rate of
work, high noise levels, vibrations and dust that can lead to allergies. Large
amounts of the greenhouse gas carbon dioxide and acidifying sulphur dioxide
are released.
 
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