1.+Introduction

=**Introduction **=

Paraffin wax refers to the solid state long chain n-alkanes that precipitate out of cooled crude oil. The paraffin wax found in crude oil follows the general formula C ﻿n H 2n+2 , is predominantly straight-chained in structure, is non-oxidized, and can contain trace amounts of branched chain isomers. Industrially, paraffin waxes are defined as long-chain carbon structures (C 16+ ), and are in their solid state at room temperature ( Schmidt  2010).

The presence of paraffin wax in crude oil present a challenge to oil producers, transporters as well as refiners. Paraffin wax precipitates and forms deposits on the pipe wall when the temperature of the pipeline drops below the Cloud Point, which is also known as the Wax Appearance Temperature. As such, the Cloud Point, or Wax Appearance Temperature, is the temperature at which paraffin wax precipitates and falls out of solution ( Schmidt  2010).

As deposition occurs, the pipe surface roughness and the cross sectional flow area reduces. This causes an increased pressure drop along the pipeline. If left untreated, it could lead to hazardous damage to the pipelines, as well as escalate the costs of production. For oil producers, the presence of heavy paraffin waxes increases the thickness of the crude, making it more difficult to recover from the well. For transporters, the increased pressure drop and the constant scaling of the pipeline could mean a loss of production and induce a costly maintenance expenditure.

Chemical treatment of waxy crude must be done in a refinery before the waxy crude can be marketed to consumers. Therefore, the profitability of a refinery also relies on the successful production and transfer of waxy crude to the refinery (Becker 1997). Regardless, the presence of other complex multiple aggregates such as emulsions, asphaltenes, silt, corrosion by-products and inorganic scales add to the problem and the difficulty of treatment (Becker 1997).

The total cost of fouling in pipeline is substantial. Studies reveal that the oil industry spends several billions of dollars annually to combat this type of fouling. Back in the early 1900's, treatment and prevention costs accounted for 0.25% of the GDP of industrial nations. More recently, the US alone has been spending roughly 2 billion dollars a year to treat paraffin wax fouling ( Mokhatab  et. al. 2009). There is an undoubted necessity for effective management solutions to paraffin fouling as it is critical for the maintenance and success of our energy sector.

<span style="font-family: Arial,Helvetica,sans-serif;"> Figure 1: Paraffin Wax Deposition in a Pipeline (Integrity Engineering 2009)

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