Industrial Ecology and the Geoenvironment - Sustainable Practices in Geoenvironmental Engineering - page 129

seawater. Removal of the impurities such as calcium, iron, aluminum, sulfate, magnesium,
and trace metals is required before the electrolysis process used to obtain the end product
(chlorine, caustic soda, and hydrogen). The three types of cells used in the electrolysis pro-
cesses for the manufacture of the products are mercury, diaphragm, and membrane.
4.6.2.1 Stressors and Impacts on Geoenvironment
The major areas of concern for land environment protection are similar to the other indus-
tries described in the previous sections. These areas are (a) deposition of smokestack
(point) and fugitive (from process equipment, leaks, and spills) emissions of particulates
and noxious substances including SO x and NO x , (b) discharge of wastewater and fugitive
process waters, and (c) solid wastes. The nature of the chemicals, especially the organic
chemicals, makes it critical to monitor both the acidity and chemistry of precipitations. For
example, ammonia (NH 3 ) and nitric acid (HNO 3 ) have been recorded as emissions from
processing for ammonium nitrate. NO, NO 2 , and SO 2 have been detected as emissions
from plants producing HNO 3 and H 2 SO 4 , respectively.
Wastewater from petrochemical industries manufacturing organic chemicals will con-
tain excess chemicals (spills?), hydrocarbons, and other dissolved solids in suspended
form. Also included are the wastewaters from maintenance procedures and washing of
equipment. These would likely contain solvents, lubricants, and detergents. In the case
of the inorganic chemical manufacturers, corresponding wastewater discharges will be
obtained, except that the surplus chemicals will be inorganic chemicals. Maintenance and
cleaning procedures will supply wastewater that would also contain lubricants and deter-
gents and perhaps some solvents.
Land disposal of waste materials would generally be in a sludge form since raw materi-
als and manufacturing processes generally do not involve solid materials. Brine muds are
perhaps the greatest “solid” wastes derived from the chemical industry. These are obtained
from the chlorine-alkali industry and are regularly disposed in brine mud ponds in a
manner similar to the holding ponds of the mining-metal industries.
4.6.3 Land Environment Impacts and Sustainability Indicators
The impacts to the land environment from the emissions, discharges, and land disposal of the
waste items are in general similar to those for the other industries described in the previous
sections. The only signiicant difference in the case of petrochemical and chemical industries
is the added chemical nature of the various emissions and discharges. The record shows that
utilization of proper scrubber systems together with stringent wastewater treatment proce-
dures have served to reduce the levels of impact to the land environment. Indicators of proper
sustainability of the land environment are obviously zero threat emissions and discharges.
4.7 Service Industries
Service industries do not necessarily create tangible goods or products. By deinition, they
are industries that create or provide services to the consumer. The major service industries
include (a) health (all aspects of medical, dental, and social services), (b) military, (c) edu-
cational, (d) government, (e) technical, and (f) inancial. Because they do not really create