Harold Becker, UNICHEM
Crude oil is a complex mixture of organic materials consisting of saturated and unsaturated linear and branched hydrocarbons, organic acids, amines, hetero atomic and polycyclic molecules combined in various proportions. Paraffins waxes are an important component of the saturated linear and branched hydrocarbon portions of these grand mixtures. They are important for several positive reasons; primary among these is their fuel value as a refinery feedstock. However, they are also important because of their tendency to negatively affect the physical properties and behavior of the crude oils in which they reside. Two important physical properties that are affected by the presence of these paraffin waxes are viscosity and deposition tendency. These properties are of significant importance to ability of oil companies transport these crude oils from the reservoir to the consumer. Paraffin waxes form networks of crystals within crude oils as the temperature drops, producing deposits on cold surfaces like pipe walls. These deposited waxes then act to impede the flow of oil fluids through the transporting conduit. But before deposits are formed the Waxes produce large increases in the viscosity of the crude oil fluids that results in higher energy costs as pumping energy requirements are rapidly escalated. Sometimes accumulations of paraffin waxes can have catastrophic consequences such as line plugging and ruptures that can result in severe environmental damage. Thus control measures that act to mitigate the negative physical properties produced by paraffin waxes are of high priority among oil producing and refining companies. Laboratory distillation methods provide good comparisons to crude oil reservoirs, since gases and fluids are forced kom areas of elevated heat and/or pressure to areas of lesser heat andor pressure within each system. In both cases, gases condense and fluids cool as they migrate kom the flask or reservoir. The condensation products may be gas, liquid, or solid at varying temperatures and pressures. In the case of paraffin waxes, these condensation products comprise a spectrum of variable carbon chain lengths ranging fkom 18 to 100+ carbons. As deeper and hotter reservoirs are put into production higher carbon chain length hydrocarbons become more prevalent, since the lighter gases and fluids have greater mobility through the porous geologic structures above. Thus, with the advent of new technologies enabling greater production depths and increased production in areas of deep water offshore, the crude oils being produced contain increased amounts of paraffin waxes.