كليدواژه :
Bandar Abbas oil , Distillation , pre-heat , Analysis and discussion
چكيده لاتين :
During the extraction of crude oil, some non-organic impurity, including salt, minerals and water, remains in crude oil.
In the separation processes which are done in upstream oil industries, a major part of these contaminants are eliminated.
Then it’s transferred to the Oil Refining industries as a feed. Another amount of the minerals and water is settled in the
refinery oil tanks. Then, crude oil is entered to the crude distillation units. But still a few impurities such as salts and
minerals have remained in the crude oil feed that with the passage through the heat exchangers will gradually make
sediment within them.
Formation of precipitation through the crude oil pre-heating sections of Distillation units is the major factors of wasting
energy in the refineries. About half of total operating cost is charged for energy in the refineries that a part of this is
because of sediment in crude oil distillation units [1]. Heat deposition in heat exchangers of pre-heat sections in
distillation units causes billions of dollars in refineries which will be additional costs [2]. For instance, in a pre-heated
section of a crude oil distillation unit with a capacity of 100,000 BPD, 1- degree temperature drop can increase the rate
of fuel cost 40,000 dollars and will release 750 tons of Carbon Dioxide [3]. Also fouling formation causes pressure drop
and consequently causes increase in loading of pumps. For the above mentioned unit, 10% pressure drop can cause
20,000 dollars additional costs per year. In some units, problems due to pressure drop take much more cost in
comparison of cost due to reduction of heat recovery [4].
On the other hand, the sediment formed on the surface of metals, causes corrosion under the fouling and creates hazards
and costs due to which those downstream oil industries always make decision to reduce it.
