When parafiin-laden crude oil is flowed through the tank, the paraffin drops out and accumulates in the series of chambers and tank side walls.
This invention relates to a parafiin accumulator and, more particularly, relates to an accumulator for removing heavy hydrocarbons from crude oil.
In some areas of the world it is not uncommon for naturally occurring crude oil to contain substantial amounts of heavier hydrocarbons which are referred to collectively as paraffin. Because of the limited solubility of such parafiins Within the crude, they tend to come out of solution when the pressure and temperature at which the crude naturally exists are lowered. As a result, it is not uncommon for paraffin to accumulate in lines leading from the wellhead to a tank battery which become restricted and ultimately blocked if remedial action is not taken.
A number of approaches have been suggested and practiced for the problem of paraffin accumulation. For instance, it is not uncommon for certain chemicals to be used either to coat the wall of the flow line to prevent sticking of the paraffin, or to keep the paraffin in solution in the crude. Unfortunately, however, no chemical agents have been found which have been completely satisfactory for this purpose. Moreover, the price of some of these materials is such as to render their commercial utility impractical. It has also been suggested to remove the accumulated paraffin at selected time intervals by pumping hot oil in the flow line to melt the paraffin and remove it. Unfortunately, however, while this method is. reasonably satisfactory, it is expensive and also prevents utilization of the equipment during the hot oil treatment. Because of these and similar limitations in prior art paraflin control methods, apparatus which is sufficiently inexpensive as to be commercially feasible, relatively foolproof in operation and which has a relatively long and trouble-free service interval between periods of downtime has remained an elusive desideratum.
It is, therefore, an object of the present invention to provide a new and improved paraflin accumulator.
Another object of the present invention is to provide an improved accumulator for removing heavier hydrocarbons from crude oil.
Yet another object of the present invention is to provide apparatus for removing parafiin from crude oil without restricting flow lines carrying such crude oil.
Still another object of the present invention is to provide mechanical equipment for removing and accumulating paraffin over long periods of time without service.
These and other objects may be achieved with apparatus embodying the present invention which, in one form, comprises an elongated, substantially horizontal tank which has an inlet and an outlet. A plurality of bafiies may be provided at spaced intervals within the tank, with each of the baffles having formed therein an aperture which is offset in relation to the apertures in adjacent baffles. The baffles are of such number and the apertures are of such size as to create a pressure drop of at least 50 p.s.i. between the inlet and the outlet of said tank during the flow of crude t-herethrough.
A more complete understanding of the present invention may be obtained from a perusal of the following detailed written description when read in conjunction with the accompanying drawing which discloses an isometric view of one form of structure embodying the invention with a portion of said structure being cut away to reveal internal elements.