RU2028538C1 - Method of piping of high-viscosity oil - Google Patents

Abstract

FIELD: oil piping. SUBSTANCE: peripheral annular flow is produced in the pipeline. Nitrogen at a temperature exceeding 50 C is pumped down the piping, then 5-10% emulsion of sulfuric anhydride with nitrogen at a subsequent treatment of the pipe space with activated water, the pH- value being within 10 to 11.5. EFFECT: facilitated procedure.

Description

 The invention relates to pipeline transportation of oil and oil products, and more particularly, to transportation of high viscosity oils through pipes where paraffin is deposited.

A known method of transporting highly viscous oils with a wall (peripheral) layer, involving the introduction of a surface-active substance (surfactant), providing hydrophilization of the pipe walls. The action of surfactants is reduced to lowering the surface tension at the oil-water interface. It is known that the hydrophilic part of the surfactant molecule may contain a sulfate group (SO ₃ ), groups containing nitrogen.

 The disadvantage of this method is the continuous input into the pipeline of an expensive surfactant and means (metering pump) for the operation, which are powered by a fire hazardous electric source.

 The closest in technical essence and the achieved result is a method of transporting highly viscous oil by creating a peripheral annular flow of water in the pipeline, covering the flow of transported high-viscosity oil.

 In this method, in the contact zone of the peripheral annular layer and the transported oil, a highly viscous water-in-oil emulsion is formed which reduces the stability of the peripheral annular flow and increases the frictional pressure loss, which reduces the efficiency of transportation.

The aim of the present invention is to increase the effectiveness of the method of preventing the deposition of paraffin in pipes. This object is achieved by the fact that in the known method transport high-viscosity oils with the creation of the peripheral annular flow in the pipe, it is pumped with nitrogen temperature over 50 ^{° C,} then 5-10% emulsion of sulfuric anhydride with nitrogen followed by treatment with activated water tube cavity with a value pH = 10-11.5.

 When 5-10% emulsion of sulfuric anhydride with nitrogen is pumped into the pipe cavity, an indelible hydrophilic surface is created due to the chemical activity of sulfuric anhydride. Due to the chemical activity of sulfuric anhydride, a highly hydrophilic surface creates a barrier between the metal surface and paraffin crystals. On such a surface, the adhesion of deposited paraffin is reduced. This is due to the fact that, due to the hydrophilicity of the surface, it always remains moist if there is even a small amount of water in the stream. This prevents a significant accumulation of paraffin. Paraffin, which is nevertheless deposited, remains very loose and is easily removed under the influence of vibration or fluid flow.

 When liquid with a high pH value is pumped into the pipe cavity, any by-products are neutralized and passivate the metal surface.

 The proposed method for transporting high-viscosity oils during oil production and its transportation through main pipelines can significantly reduce funds for the forced repair of wells from the deposition of paraffin in pipes, as well as the restoration of the transmission capacity of the pipeline.

Claims (1)

METHOD FOR TRANSPORTING HIGH VISCOUS OILS with the creation of a peripheral ring flow in the pipeline, characterized in that nitrogen is pumped into the pipeline with a temperature of more than 50 ^o С, then a 5 - 10% emulsion of sulfuric anhydride with nitrogen, followed by treatment of the pipe cavity with activated water with a pH value of 10 - 11.5.