The input of the
life cycle inventory analysis covers the air and water required.
The air requirement is mostly
related to the need for oxygen when burning the fossil resources to get energy.
The tire of a car’s use phase uses the largest part of overall air consumption
in the life of a tire. The other parts of a tire’s life are: raw materials,
extraction, production and transport (Continental, 1999).
The water consumption exists of
cooling water, process water and service water. Cooling water normally goes
into circuits that’s why they can be used over a long period of time. The water
consumption in combination with the obtaining raw materials for the carbon black
tires under consideration here is as follows: around 63% for the manufacture of
synthetic rubber, around 18% to obtain rayon, around 3.1% for the manufacture
of natural rubber, around 5.6% for the production of steel and around 6.5% for
the manufacture of chemicals (Continental, 1999).
The output of the life cycle inventory
analysis is made up of the atmospheric emissions, emissions into water, and
Atmospheric emissions are
persistent for the biggest part by the output of carbon dioxide. The left overs
contain carbon monoxide and water vapor. Other emissions are methane, nitrogen
oxide, volatile organic hydrocarbons but methane, sulfur dioxide, ammonia, nitrous
oxide and dust are excluded (Environ, 2002). Of all the phases in the life of a tire, the
car use phase is the reason for a big negative impact on the atmosphere. This
negative impact is almost entirely caused by the carbon dioxide which is
released when the car is being used. Carbon monoxide makes up around 1.2% of the
negative impact on the atmosphere in the use phase. The other phases like
obtaining raw materials for the tire and transport have less influence on
atmospheric emissions. Dust is produced almost entirely
in the use phase and contains mainly particles of diverse sizes which are produced
by tire abrasion. The particles get into the air and slowly fall to the ground.
Water vapor is released when the tire is manufactured. It is made because of
cooling processes in the course of the manufacture of the rubber mixture as
well as of components (Continental, 1999).