CLEANING EXPANSER GASES FROM CO2 AND OTHER ADDITIVES

ABSTRACT

Today, the increasing demand for natural gas in the world has led to the development of knowledge about its processing and purification. This article provides information on the purification of expander gases from CO₂ and H₂S emitted at the “UCHQIR” gas processing plant. In this case, the expander gases were passed through various absorbent solutions. Amines chemisorb H₂S and slaked lime was used to precipitate CO₂.

АННОТАЦИЯ

Сегодня увеличение потребности в природном газе в мире привело к развитию знаний о его переработке и очистке. В данной статье представлена ​​информация об очистке экспанзеровых газов от CO₂ и H₂S, выбрасываемых на газоперерабатывающем заводе “UCHQIR”. В этом случае детандерные газы пропускались через различные растворы абсорбента. Амины хемосорбируют H₂S, а известковый раствор использовали для осаждения CO₂.

Keywords: natural gas, separator, dehydrator, extractor, condensate, carbon dioxide.

Ключевые слова: природный газ, сепаратор, осушитель, экстрактор, конденсат, углекислый газ.

In addition to its primary function as a fuel, it is a source of hydrocarbons for the natural petrochemical industry. Today, there is a lot of research going on in the field of natural gas. The main reason for this is the presence of a high concentration of methane in natural gas and the production of other potential products from it, such as synthesis gas and high-purity hydrogen[1-5].

While natural gas is generally considered a "clean" fuel compared to other fossil fuels, natural gas found in water deposits is not necessarily "clean" and free of impurities[6-9]. Natural gas consists mainly of methane, and it contains large amounts of light and heavier hydrocarbons, as well as CO₂, N₂, Hg, He, H₂S and other additional compounds. Thus, pipelines used as consumer fuel must be cleaned of additives in order to meet quality standard requirements, increase the calorific value of natural gas, prevent corrosion of pipes and equipment, and eliminate related technological problems[10-13].

The processing of natural gas extracted from wells into high-quality dry natural gas is quite complex and usually involves several processes. Often, the number of gas treatment steps and the type of methods used to obtain quality natural gas depend on the source and composition of the production stream along the well[14-16].

A number of operations were carried out in order to clean the additives contained in the expander gases. A technology has been developed to clean expander gases from CO₂ and separate it for various purposes in industry. this technology is illustrated in picture 1.

Figure 1. Technological scheme of CO₂ purification of expander gases

For the chemical purification of CO₂, it is combined with Ca(OH)₂ and separated in the form of CaCO₃. The chemical reaction equation of the process is described below.

CO₂ + Ca(OH)₂ = CaCO₃↓+ H₂O

Most alkanolamines are widely used as chemical solvents for CO2 removal in the natural gas and oil refining industries. In these processes, alkanolamine or soluble calcium salts are used in aqueous solution. The amine-based solvents used for the absorption process are monoethanolamine (MEA), diethanolamine (DEA), and methyldiethanolamine (MDEA), which bind to CO₂ and H₂S. These amines are called weak organic bases. Amines provide basicity and are used to clean expander gases from CO₂ and H₂S. Hydroxide groups increase the solubility of amines in water.

In view of the above, Table 1. shows a comparison of absorption processes of chemical and physical solvents for the attachment of CO₂ and H₂S.

Table 1.

Comparison of absorption processes of CO₂ and H₂S gases

In conclusion, it can be said that methane is the main component of expander gases. But due to the low pressure of these gases, they cannot be re-added to the system. Therefore, cleaning these gases from acidic parts and delivering them to the population for use is very relevant today. Expander gases contain up to 85-87% methane gas, which after purification reaches 98-99%.

References:

1. Olimov B., Akhmedov V. The effect of reaction duration and catalyst on the synthesis of arylvinyl esters //Збірник наукових праць ΛΌГOΣ. – 2020. – С. 33-37.
2. Ахмедов В. Н., Олимов Б. Б. Способ получения виниловых эфиров на основе винилацетилена //Gaydar Aliyevning. – 2020. – Т. 97.
3. Olimov B., Akhmedov V., Gafurova G. Production and use of corrosion inhibitors on the basis of two-atomic phenols and local raw materials //Главный редактор. – 2021. – Т. 7. – С. 85.
4. Bobir O., Vokhid A., Gulnoz G. Production and use of corrosion inhibitors on the basis of two-atomic phenols and local raw materials //Universum: химия и биология. – 2021. – №. 11-2 (89). – С. 85-88.
5. Olimov B. B., Yoldosheva N. J. Gravimetric study of the mechanism of action of corrosion inhibitors used in the oil and gas industry //Международный научно-образовательный электронный журнал «Образование и наука в xxi веке». Выпуск. – №. 19.
6. Назаров Ш. и др. Синтез мономеров при участии винилацетилена из одноатомных фенолов содержащих ариловую группу //Universum: химия и биология. – 2020. – №. 11-2 (77).
7. Олимов Б. Б., Ахмедов В. Н. Винилацетилен асосида фенолларнинг винил эфирлари синтези.“Замонавий ишлаб чикаришнинг мухандислик ва технологик муаммоларини инновацион ечимлари” Халкаро илмий анжуман материаллари //Замонавий ишлаб чикаришнинг мухандислик ва технологик муаммоларини инновацион ечимлари” Халкаро илмий анжуман материаллари Бухоро. – 2019. – С. 37-39.
8. Shomurod N., Vokhid A., Bobir O. Preliminary quantum chemical analysis of synthesized monomers with the participation of vinylacetylene //International journal of progressive sciences and technologies. – 2020. – Т. 22. – №. 2. – С. 50-56.
9. Ахмедов В. Н., Олимов Б. Б. У., Назаров Ш. К. Электронная структура и квантово-химические расчёты виниловых эфиров фенолов //Universum: химия и биология. – 2020. – №. 4 (70).
10. Olimov B. B., Ahmedov V. N., Hayitov S. Ikki atomli fenollar asosida vinilli efirlarni olish usullari //Fan va texnologiyаlar taraqqiyoti ilmiy–texnikaviy jurnal. – 2020. – №. 1.
11. Olimov B. B., Akhmedov V. N., Gafurova G. A. Application of derivatives of diatomic phenols as corrosion inhibitors //Euro Asian Conference on Analytical Research (Germany. – 2021. – Т. 15. – С. 136-138.
12. Ахмедов В., Олимов Б., Гафурова Г. Винилачетилен иштирокида винил эфирлар олиш. НамДУ илмий ахборотномаси-Научный вестник НамГУ. – 2021.
13. Bahodirovich, Olimov B., et al. "Synthesis of Resorcinol Vinyl Ether in the Mono-position, Influence of the Catalyst, Temperature and Solvent on the Reaction Yield." JournalNX, 2020, pp. 44-51.
14. Olimov B.B., Sadiqova M.I., Beshimov I.A. Technology of obtaining effective corrosion inhibitors in the oil and gas industry // Universum: технические науки : электрон. научн. журн. 2022. 1(94). URL: https://7universum.com/ru/tech/archive/item/12950
15. Олимов Б.Б., Гафурова Г.А., Кудратов О.Х. Production and properties of corrosion inhibitors in the oil and gas industry // Universum: химия и биология : электрон. научн. журн. 2022. 2(92). URL: https://7universum.com/ru/nature/archive/item/13009