RU2312070C2 - Hydrogen sulfide neutralization composition - Google Patents

Abstract

FIELD: petroleum industry.

SUBSTANCE: hydrogen sulfide neutralization composition applicable in oil production and treatment systems includes aqueous ammonia solution, 98.0-99.3%, complexing agent, 0.5-1.5%, and additionally nonionic surfactant, 0.2-0.5%. Complexing agent is selected from group consisting of: polyaminophosphonic acid, nitrilotrimethyl-phosphonic acid, 1-oxyethylene-diphosphonic acid, tetramethylene-phosphonic acid, or derived thereof. Surfactant is nitrogen-containing ethylene oxide/propylene oxide block copolymer. Aqueous ammonia solution is used in amount allowing consumption of 0.5 mole ammonia per 1 mole hydrogen sulfide. Composition according to invention is effective neutralizer of hydrogen sulfide and other acidic components (mercaptans) in well products and show elevated reactivity. Neutralization process involving proposed composition is not accompanied by precipitation of salts in rejected formation water. In addition, use of composition allows complications (such as difficult water separation) in commercial petroleum provision technology to be avoided.

EFFECT: improved performance characteristics of composition.

1 tbl, 4 ex

Description

The invention relates to the oil industry and can be used in the extraction of oils containing hydrogen sulfide.

Among the closest formulations (analogue) are known, for example, the use of a bactericide (neutralization of hydrogen sulfide) Soncid 8101 (TU 2458-012-00151816-99) [http: //www.ozneftechim.m/soncid8101.htm].

The disadvantage of the analogue is the low absorption capacity of the neutralizing liquid with respect to hydrogen sulfide. To ensure effective neutralization of hydrogen sulfide, large volumes of bactericide are required to be injected into the well (1:20), which leads to an increase in material and energy costs.

The claimed composition is close (prototype) composition for the neutralization of hydrogen sulfide, which contains an aqueous solution of ammonia in the composition with a scale inhibitor ISB-1 [Mavlyutova MZ, Mambetova LM, Borisov VP Improving the efficiency of oil preparation processes in fields using ammonia. - Sat tr BashNIPIneft. - Ufa, 1985 .-- Issue 72. - 28 p.].

The disadvantage of the prototype is that it is fed into a system where the components of the well’s production are already divided into oil, gas and water, and therefore does not allow to effectively neutralize the hydrogen sulfide contained in each component. When neutralizing hydrogen sulfide with the prototype composition, there are complications associated with the subsequent dehydration of commercial oil.

The basis of the present invention is the creation of a composition having a higher reactivity to neutralize hydrogen sulfide and other acidic components (mercaptans) in the oil production and preparation system. In the process of neutralizing hydrogen sulfide, the proposed composition does not precipitate salt in discharged formation water. In addition, the use of the composition avoids the manifestation of complications in the technology for the preparation of commercial oil, contributing to better separation of water.

The problem is solved in that the composition for neutralizing hydrogen sulfide in the oil production and preparation system includes aqueous ammonia and a complexing agent, and further comprises a nonionic surfactant - a nitrogen-containing block copolymer of ethylene and propylene oxides; complexing agent - polyaminephosphonic acid, or nitrilotrimethylphosphonic, or 1-hydroxyethylene diphosphonic, or tetramethylenephosphonic, or their derivatives; while an aqueous solution of ammonia is used in an amount providing a flow rate of 0.5 mol of ammonia per 1 mol of hydrogen sulfide, in the following ratio of components, in wt.%:

- aqueous ammonia solution - 98.0-99.3;

- complexing agent - 0.5-1.5;

- nonionic surfactant - 0.2-0.5.

An analysis of the known technical solutions selected in the search process showed that in science and technology there is no object similar in terms of the claimed combination of features and advantages, which allows us to conclude that its criteria are “novelty” and “inventive step”.

Compliance with the criterion of "industrial applicability" is proved below by specific examples (table).

Example 1. In the oil emulsion (water cut 5%, hydrogen sulfide content 1200 mg / dm) to neutralize the hydrogen sulfide was added the inventive composition and the composition of the prototype in the amount of 1.2 l / t

Example 2. The content of hydrogen sulfide in oil 500 mg / DM. 250 mg / t of the composition was added per 1 ton of oil to neutralize hydrogen sulfide and kept for 2 hours.

Example 3. An oil emulsion with a water content of 30% with a hydrogen sulfide content of 620 mg / dm was treated with the prototype composition (300 mg / t) and the inventive composition for neutralizing hydrogen sulfide (200 mg / t). Stand for 2 hours.

Example 4. In oil with a water content of 1.5% and hydrogen sulfide 50 mg / dm was added the inventive composition to neutralize hydrogen sulfide and a prototype in an amount of 20 mg / t

Table
Test results Example Composition for neutralizing hydrogen sulfide The content of hydrogen sulfide, mg / DM ³ The water content in oil,% source residual source residual one claimed 1200 0 5 0.01 prototype 0 5 2 claimed 500 1,0 0.1 0.01 prototype 25 0.1 3 claimed (200 mg / t) 620 0.5 thirty 0.2 prototype (300 mg / t) 23 25 four claimed fifty 0 1,5 0.01 prototype 0 1,5

The data presented in examples 1-4 show that the neutralization of hydrogen sulfide by the claimed composition is most effective compared to the known. The composition for neutralizing hydrogen sulfide in the oil production and preparation system allows not only to completely remove hydrogen sulfide (0-1.0 mg / dm against 0-23 mg / dm in the prototype), but also provides an additional reduction in the residual water content in oil (0, 01-0.2% against 0.1-25.0% of the prototype).

In all examples, the hydrogen sulfide content in the aqueous phase was determined according to OST 39-234-89 "Water for flooding oil reservoirs. Determination of hydrogen sulfide content. " The hydrogen sulfide content in oil was determined according to GOST 50802-95 “Determination of hydrogen sulfide in marketable oil”, by the method (absorption of hydrogen sulfide by alkali, followed by precipitation with a solution of cadmium acetate), chromatographic method.

Claims (1)

A composition for neutralizing hydrogen sulfide in an oil production and preparation system, including aqueous ammonia and a complexing agent, characterized in that it further comprises a nonionic surfactant - a nitrogen-containing block copolymer of ethylene and propylene oxides; complexing agent - polyaminephosphonic acid, or nitrilotrimethylphosphonic, or 1-hydroxyethylene diphosphonic, or tetramethylenephosphonic, or their derivatives; while an aqueous solution of ammonia is used in an amount providing a flow rate of 0.5 mol of ammonia per 1 mol of hydrogen sulfide, in the following ratio of components, wt.%: aqueous ammonia 98.0-99.3 complexing agent 0.5-1.5 nonionic surfactant 0.2-0.5