WO2024030043A1 - Method for combustion of hydrocarbon fuel - Google Patents

Abstract

The invention relates to a chemical process for the combustion of hydrocarbon fuel, and more particularly to a process for the combustion of hydrocarbon gases, hydrocarbon liquids, and petroleum residues. The method includes combusting fuel in a mixture of a recycle stream of the flue gases produced in the combustion process, a recycle stream of carbon dioxide and nitrogen, a stream of oxygen, and a stream of atmospheric air; removing flue gases from the fuel combustion zone, with the flue gases being partially recycled into the combustion zone; feeding the balance of flue gases to a process for the extraction of carbon dioxide for subsequent storage and the separation of condensate; and recycling carbon dioxide into the combustion zone. The method provides for more efficient extraction of carbon dioxide from the stream of flue gases for subsequent storage, thus reducing the environmental impact.

Description

COMBUSTION METHOD OF HYDROCARBON FUEL

TECHNICAL FIELD

The invention relates to the chemical process of combustion of hydrocarbon fuel, in particular, to the process of combustion of hydrocarbon gases, hydrocarbon liquids, oil residues, to produce thermal energy for its subsequent beneficial use, as well as the capture/recovery of carbon dioxide for subsequent transportation to storage and reduction sites greenhouse gas emissions into the atmosphere.

BACKGROUND OF THE ART

The closest analogue is the method of fuel combustion with subsequent capture of carbon dioxide US2009075219 (A1), published on March 19, 2009. The method includes supplying an oxygen flow to the combustion chamber with subsequent condensation of water vapor, releasing part of the flue gases into the atmosphere and part of the flue gases to the capture process carbon.

The disadvantage of this method is the inability to regulate the concentrations of components in the flue gas flow for oxygen in the concentration range from 1% vol. up to 50% vol., for carbon dioxide from 1% vol. up to 50% vol., nitrogen concentration no more than 30% vol., as well as the need for condensation of water vapor, which is ensured by reducing the temperature of the flue gases to 15 °C, which in turn requires significant operating costs for cooling. The patent also does not include the recirculation of the flue gas flow back into the combustion process zone of hydrocarbon gas, hydrocarbon liquid, oil residues and the recirculation of the carbon dioxide and nitrogen flow after the carbon capture process in order to regulate the concentration of components in the combustion zone.

Carrying out the process according to the method and conditions described in patent US2009075219 (A1) leads to an increase in operating costs by 35-45%, which does not allow us to consider this method acceptable for the industrial implementation of the combustion process of hydrocarbon gas, hydrocarbon liquid, and oil residues.

DISCLOSURE OF INVENTION

The objective of the claimed invention is to develop a method for burning hydrocarbon fuels in order to integrate with the carbon dioxide capture process, allowing to reduce the operating costs of the capture process by up to 40% and increase the concentration of carbon dioxide in the flue gas stream by up to 50%.

The technical result of the proposed invention is a reduction in operating costs for the carbon dioxide capture process by 40% and a proportional reduction in greenhouse gas emissions into the atmosphere due to capture and transportation to storage sites.

The specified technical result is achieved due to the fact that the combustion method is carried out for hydrocarbon gas, hydrocarbon liquid, oil residues while ensuring combustion in flows with a given concentration of oxygen, nitrogen and carbon dioxide in the required proportions, for oxygen in the concentration range from 1% vol. up to 50% vol., for carbon dioxide from 1% vol. up to 50% vol., minimum nitrogen concentration up to 30% vol.

Atmospheric air is supplied to the station/installation for separation into components, containing nitrogen and oxygen in a proportion of 79% vol. and 21% vol. Next, the oxygen flow is directed as an oxidizer to the fire heater to ensure the combustion process of the hydrocarbon gas, hydrocarbon liquid, oil residues at a temperature of 800-1400 °C. The resulting flue gases from the combustion of hydrocarbon fuels are sent to a smoke exhauster/compressor to feed the carbon capture process. A portion of the flue gas flow from the smoke exhauster/compressor is recycled back to the oxygen flow to regulate the concentration of carbon dioxide, nitrogen and oxygen in the hydrocarbon fuel combustion zone.

In the process of capturing carbon dioxide from flue gases, two concentrated streams are formed: the 1st stream of water condensate and the 2nd stream of carbon dioxide, resulting from the combustion of hydrocarbon fuels. The balance amount of carbon dioxide captured in the process is sent to storage.

A portion of the carbon dioxide and nitrogen stream from the carbon capture process is fed as a recycle stream back to the oxygen stream to control the concentration of carbon dioxide, nitrogen and oxygen in the hydrocarbon fuel combustion zone.

The use of an oxygen flow, flue gas recycle and carbon dioxide recycle after the carbon capture process allows for an increase in the concentration of carbon dioxide in the flue gas flow to 50% vol., which fundamentally simplifies the organization of the carbon dioxide capture process, reduces capital and operating costs for capturing 1 ton carbon dioxide. Also, the supply of oxygen and recycle of flue gases, recycle of carbon dioxide makes it possible to reduce the concentration of nitrogen to 30% vol., which is a diluent and an inert gas, significantly complicating the operating mode of the carbon dioxide capture process.

IMPLEMENTATION OF THE INVENTION

Atmospheric air is supplied to the station/installation for separation into components (5) - nitrogen and oxygen. Next, the oxygen flow is sent as an oxidizer to the fire heater (1) to ensure the combustion of hydrocarbon fuel. The resulting flue gases from the combustion of hydrocarbon fuels are sent to the smoke exhauster/compressor (3) to feed the carbon capture process (4). A portion of the flue gas stream from the exhaust fan/compressor can be recycled back to the oxygen stream to control the concentration of carbon dioxide, nitrogen and oxygen in the hydrocarbon fuel combustion zone of the heater/evaporator (1). Flue gas recycle can range from 0.1 to 1000 parts per 1 part hydrocarbon fuel.

In the process of capturing carbon from flue gases, two concentrated streams are formed: 1st stream of condensate water resulting from the combustion of hydrocarbon fuels; 2nd stream of carbon dioxide, also formed during the combustion of hydrocarbon fuels. The balance amount of carbon dioxide captured in the process (4) is sent to the storage location (6).

A portion of the carbon dioxide and nitrogen stream from the carbon capture process (4) may be supplied as a recycle stream back to the oxygen stream to control the concentration of carbon dioxide, nitrogen and oxygen in the hydrocarbon fuel combustion zone of the heater/evaporator (1). The recycle of carbon dioxide and nitrogen from the capture process (4) can range from 0.1 to 1000 parts per 1 part hydrocarbon fuel.

The use of oxygen flow, flue gas recycle and carbon dioxide recycle after the carbon capture process makes it possible to increase the concentration of carbon dioxide in the flue gas stream from 12% vol. up to 50% vol. , which fundamentally simplifies the organization of the carbon capture process, reduces capital and operating costs for capturing 1 ton of carbon. Also oxygen supply and flue gas recycle, carbon dioxide recycle allows you to reduce the concentration of nitrogen, which is a diluent and an inert gas that significantly complicates the operation of the carbon capture process (4),

In fig. 1 shows a diagram of the combustion process of carbon fuel according to the claimed invention

(1) - fire heater/evaporator having a combustion chamber for hydrocarbon fuel;

(2) - a consumer of thermal energy or a convector of thermal energy into other types of energy;

(3) - smoke exhauster/compressor, a device that provides transport of the volume of flue gases from the fire heater/evaporator to the process of capturing carbon from the flue gases, as well as recycling part of the flue gases back to the fire heater/evaporator;

(4) - the process of capturing carbon from flue gases;

(5) - the process of separating air into components - nitrogen and oxygen;

(6) - storage location for captured carbon dioxide.

Example 1

The combustion process is carried out for hydrocarbon gas in an amount of 100 kg/h. To ensure combustion, atmospheric air is supplied in proportion to the station/installation for separation into components in an amount of up to 150 kg/h, containing nitrogen and oxygen in a proportion of 21% vol. and 79% vol. Next, the oxygen flow is sent as an oxidizer to the fire heater to ensure the combustion of hydrocarbon gas at a temperature of 900-1100 °C. The resulting flue gases from the combustion of hydrocarbon fuels are sent to a smoke exhauster/compressor to feed the carbon capture process. A portion of the flue gas flow from the smoke exhauster/compressor is recycled back to the oxygen flow to regulate the concentration of carbon dioxide, nitrogen and oxygen in the hydrocarbon fuel combustion zone. In this case, the oxygen concentration is 42% vol. , carbon dioxide 29% vol., nitrogen 29% vol.

In the process of capturing carbon dioxide from flue gases, two concentrated streams are formed: 1st stream of water condensate resulting from the combustion of hydrocarbon fuels; 2nd stream of carbon dioxide, also formed during the combustion of hydrocarbon fuels. The balance amount of carbon dioxide captured in the process is sent to storage.

A portion of the carbon dioxide and nitrogen stream from the carbon capture process is fed as a recycle stream back to the oxygen stream to control the concentration of carbon dioxide, nitrogen and oxygen in the hydrocarbon fuel combustion zone. The recycle of carbon dioxide and nitrogen from the capture process is up to 100 parts per 1 part hydrocarbon fuel.

The use of oxygen flow, flue gas recycle and carbon dioxide recycle after the carbon capture process makes it possible to increase the concentration of carbon dioxide in the flue gas stream to 29% vol., which fundamentally simplifies the organization of the carbon dioxide capture process, reduces capital and operating costs for capturing 1 ton carbon dioxide. Also, the supply of oxygen and recycle of flue gases, recycle of carbon dioxide makes it possible to reduce the concentration of nitrogen to 29% vol., which is a diluent and an inert gas, which significantly complicates the operating mode of the carbon dioxide capture process.

Claims

CLAIM 1. A method of combustion of hydrocarbon fuels, in which the following sequence of actions is carried out: a), concentration of oxygen from the air; b). combustion of hydrocarbon fuel in a mixture of a recycle stream of flue gases generated during the combustion process, a recycle stream of carbon dioxide and nitrogen, a stream of oxygen and a stream of atmospheric air; c), removal of flue gases from the hydrocarbon fuel combustion zone through the use of a smoke exhauster and/or compressor, with partial recycle of gases into the combustion zone; d). supplying a balance amount of flue gases to the carbon dioxide extraction process for the purpose of subsequent storage and release of water condensate; e). recycle of carbon dioxide into the hydrocarbon fuel combustion zone. 2. The method according to claim 1, characterized in that the combustion process of hydrocarbon fuel is carried out in an environment with a high oxygen content in the concentration range from 1% vol. up to 50% vol.; 3. The method according to claim 1, characterized in that the combustion process of hydrocarbon fuel is carried out in an environment with a high content of carbon dioxide in a concentration range from 1% vol. up to 50% vol. 4. The method according to claim 1, characterized in that the combustion process of hydrocarbon fuel is carried out in an environment with a nitrogen concentration of no more than 30% vol.; 5. The method according to claim 1, characterized in that the combustion process of hydrocarbon fuel is carried out in combination with the subsequent removal of the balance amount of carbon dioxide to storage areas. 6. The method according to claim 1, characterized in that the combustion process of hydrocarbon fuel is carried out with recycle of the flue gas flow and recycle of carbon dioxide and nitrogen. 7. The method according to claim 1, characterized in that the combustion process of hydrocarbon fuel is carried out with the supply of an oxygen flow obtained by enrichment from atmospheric air.