RU2480505C1 - Composition of inhibitor of asphalt-resin-paraffin deposits of binary action - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: composition of an inhibitor of asphalt-resin-paraffin deposits, including a reagent 1 and a reagent 2 at their mass ratio of 33.4% to 66.6%, where the reagent 1 is a product of synthesis of stearic acid and polyethylene polyamines at their mole ratio of 1.63 to 1, and the reagent 2 - the product of synthesis of stearic acid and pentafluoride at their mole ratio of 3 to 1.

EFFECT: increased inhibiting capacity.

3 ex, 1 tbl

Description

The invention relates to the field of development and operation of oil fields, complicated by the formation of asphalt-resin-paraffin deposits (paraffin).

In order to reduce paraffin formation in oil production, paraffin scale inhibitors are used, such as: a copolymer of acrylic and methacrylic acids (DN-1 additive), ethylene vinyl acetate copolymers (VES 501 additive), a condensation product of synthetic fatty acids and triethanolamine in kerosene (Azolate-7 additive) ), block copolymers of oxyalkylated alkyl phenols and ethylenediamine, foreign inhibitors of the company Nalko and Servo-Champion, foreign inhibitor of HT-48, etc. [Olenev L.M. New domestic paraffin inhibitors. - M .: VNIIOENG, 1990. - 51 s], additive TyumII-77 [RF Patent 2326153 C1, 2008].

Closest to the claimed invention in terms of features is a method of inhibiting paraffin deposits in the presence of a composition of additives DP-65 and TyumII-77 with their mass ratio of 1: 3 [RF Patent 2326153, C09K 8 / 524,2006]. Additive DP-65 is a product of the synthesis of synthetic fatty acids (FFA) of fraction C _21-25 and polyethylene polyamines (PEPA) [RF Patent 2106395, C 10 M 149/14, 149/22, 1998]. The additive TyumII-77 is a product of the synthesis of a fraction of synthetic fatty acids with pentaerythritol and phthalic anhydride [A.S. 1063802 USSR. B.I. No. 48. 09/01/1983].

The described additive composition is a combination of depressant and modifier types. The TyumII-77 depressant type reagent prevents the formation of the crystalline structure of hydrocarbons, thereby lowering the pour point, and the DP-65 reagent is a modifying type reagent that directly interacts with solid hydrocarbon molecules, thereby lowering their cloud point [Agaev SG, Grebnev A.N., Zemlyansky E.O .: Inhibitors of paraffin deposits of binary action // Oilfield business. 2008. - No. 9. - p. 46-52.]

However, the composition of the additives described is not sufficiently effective for inhibiting the paraffin sediment of various compositions. In addition, there is currently no production of a synthetic fatty acid fraction in Russia, which makes it impossible to establish the production of additives DP-65 and TyumII-77 based on domestic raw materials.

The claimed invention allows to increase the inhibitory ability of this composition by developing analogues of its components with improved properties and based on industrially produced in Russia raw materials.

This goal is achieved by the fact that in the manufacture of both components of a composite paraffin inhibitor, stearic acid (SC), industrially produced in Russia, is used instead of synthetic fatty acids (FFA). Also, in the manufacture of the ester component, phthalic anhydride is not used, which greatly facilitates industrial production and reduces the cost of the inhibitor. The components of the developed inhibitor are two reagents: the product of the synthesis of stearic acid (SC) and polyethylene polyamines (PEPA) at a molar ratio of 1.63: 1.0 (Reagent 1), as well as stearic acid (SC) and pentaerythritol (PE) at a molar ratio of 3 0: 1.0 (Reagent 2). The mass ratio of reagents: reagent 1 - 33.4% of the mass. to reagent 2 - 66.6% of the mass.

Example 1

To obtain reagent 1, stearic acid (SC) (technical grade allowed) and reactive grade polyethylene polyamines with the degree of polymerization of the amine group (1-6), technical diethylbenzene as a solvent and zinc oxide as a catalyst are used.

The synthesis of SC and PEPA amides is carried out in a 50% solution of these reagents in diethylbenzene at its boiling point of 183 ° С in a reactor equipped with a Dean-Stark trap. The molar ratio of SC: PEPA is 1.63: 1.0, which corresponds to a mass ratio of these reagents of 3.67: 1.0. To accelerate the reaction, zinc oxide catalyst is introduced into the reactor (2 wt% for loading reagents). The synthesis is carried out until the reaction water is completely distilled off into a Dean-Stark trap with mechanical stirring of the order of 12 hours. Then diethylbenzene was completely distilled off and the reaction was continued in the melt at a temperature increase from 183 to 235 ° C to obtain amides with an acid number of 8 mg KOH / g.

Example 2

To obtain reagent 2, stearic acid (SC) and pentaerythritol (PE) are used, chemically pure, as well as technical diethylbenzene as a solvent and zinc oxide as a catalyst.

The synthesis of esters of SC and PE is carried out in a 50% diethylbenzene solution at its boiling point of 183 ° C. The molar ratio of SC and PE is 3.0: 1.0, and the mass ratio is 6.26: 1.00; zinc oxide is used as a catalyst (0.5% wt. Per reagent charge). The synthesis is carried out until the reaction water is completely distilled off into a Dean-Stark trap, also filled with diethylbenzene. Samples are taken every hour to determine the acid number. When the acid value drops below 10 mg KOH / g, the synthesis is stopped, diethylbenzene is completely distilled off. The total synthesis time is 4 hours.

Example 3

To obtain the composition of reagent 1 and reagent 2, a true solution of these reagents is prepared with their mass ratio of reagent 1 to 33.4% of the mass. to reagent 2 - 66.6% of the mass. in any of the following hydrocarbon solvents: Nefras 80/120, hexane, gasoline, kerosene, diesel, oil, gas condensate, fuel oil, benzene, toluene. The composition of these reagents is metered into the well or pipeline in the form of a solution.

Table 1 presents the results of the inhibition of asphalt-resin-paraffin deposits from a 10% paraffin paraffin system in hexane in the presence of a prototype composition, i.e. in the presence of the additive composition DP-65 / TyumII-77, the best commercial samples of domestic and foreign inhibitors, as well as in the presence of a series of additive compositions based on polyethylene polyamines and pentaerythritol. The reagent composition developed by us is assigned a code.

Table 1 The study of the inhibition of domestic and foreign additives of paraffin and sediment Agan field and ceresin brand 75 by the cold rod method in 10% of the mass. solution of precipitated hydrocarbons in hexane Solid hydrocarbons and paraffin Inhibitor Cipher The degree of inhibition of paraffin (%) with the content of additives,% mass. 0.02 0.05 0.1 0.2 one Paraffin DP-65 / TyumII-77 -60.51 -11.52 26.09 80.61 21.43 Agansky DP-163 / DP-31 PP-163/312 21.98 84.94 73.01 12.15 -53.22 place SNPCH-4002 7.18 35,4 -59.71 36.04 46.33 denia Sepaflux-3153 -19.3 8.73 3.06 50.06 73.75 Ceresin DP-65 / TyumII-77 24.34 42.97 56.68 32.36 -115.1 brand 75 DP-163 / DP-31 PP-163/312 6 17.72 42.79 75,5 34.22 SNPCH-4002 23.79 -38.13 36.19 15.79 28.01 Sepaflux-3153 31.37 54.96 68.67 74.12 80.64

From the analysis of the data in Table 1, it is clear that all synthesized additive compositions are characterized by some inhibitory properties, however, the PP-163/312 additive is most effective in inhibiting the AHPA paraffin deposits extracted from the tubing, which is the technical result of this patent search. The composition synthesized by us exceeds the prototype DP-65 / TyumII-77, and is also more effective and economical than the foreign additive Sepaflux-3153. The synthesized additive composition PP-163/312 certainly surpasses the domestic additive Kazan production SNPCH-4002.

Testing the inhibitory properties of additives in a solution of ceresin brand 75 in hexane was carried out in order to determine the ability of the synthesized compositions to inhibit paraffin under the condition of paraffinization at low temperatures. In accordance with the work [Galikeev R.M. Thesis for the degree of candidate of technical sciences. 2011] at temperatures below 20 ° C, the prevailing paraffinization mechanism changes from absorption-adhesion to crystallization. In accordance with this, paraffinization is primarily affected by the individual crystallization of paraffin-naphthenes included in paraffin paraffin, therefore, in order to inhibit paraffin paraffin, it is necessary that the additive possess depressive properties.

The best results in the inhibition of ceresin brand 75 shows the additive Sepaflux-3153, however, we obtained the most effective composition PP-163/312 at a concentration of 0.2% by weight. It has no less effect, due to which it can also be recommended for use for the inhibition of paraffin deposits in main oil pipelines.

Claims (1)

The composition of the inhibitor of asphalt-resin-paraffin deposits, including reagent 1 and reagent 2 with a mass ratio of 33.4% to 66.6%, characterized in that in the manufacture of reagent 1, only stearic acid and polyethylene polyamines are used, and for the manufacture of reagent 2, stearic acid and pentaerythritol are used, reagent 1 is a product of the synthesis of stearic acid and polyethylene polyamines with a molar ratio of 1.63 to 1, and reagent 2 is a product synthesis of stearic acid and pentaerythritol at a molar ratio of 3 to 1.