CN213713996U

CN213713996U - Cement kiln flue gas carbon dioxide enrichment and trapping apparatus

Info

Publication number: CN213713996U
Application number: CN202022839899.XU
Authority: CN
Inventors: 吴涛; 康宇; 桑圣欢; 王东
Original assignee: Nanjing Kisen International Engineering Co Ltd
Current assignee: Zhongcai International Intelligent Technology Co ltd
Priority date: 2020-11-30
Filing date: 2020-11-30
Publication date: 2021-07-16
Anticipated expiration: 2030-11-30

Abstract

The utility model relates to a cement kiln flue gas carbon dioxide enrichment and catching device, which comprises a kiln system and a raw material grinding system, wherein the kiln system comprises a kiln tail system, a rotary kiln and a grate cooler which are sequentially connected along a material path; the kiln tail system is characterized by also comprising a dust collector, a carbon dioxide collecting and refining device and an oxygen generating device, wherein an air inlet of the dust collector is connected with an air outlet of the kiln tail system, an air inlet of the carbon dioxide collecting and refining device and an air inlet at the high-temperature end of the grate cooler are connected to the air outlet of the dust collector in parallel, and an air outlet of the oxygen generating device is connected with the air inlet at the high-temperature end of the grate cooler through a first pipeline; the utility model discloses let in pure oxygen or oxygen-enriched gas as make-up gas in to the kiln system with the help of oxygenerator to improve the oxygen content in the combustion air in the kiln system, and then form the flue gas that contains high concentration oxygen in the cold machine of comb and pass through the manifold cycles in the kiln system, thereby show and improve the carbon dioxide content in the flue gas of discharge in the kiln tail system, in order to do benefit to the entrapment of carbon dioxide entrapment refining plant to carbon dioxide.

Description

Cement kiln flue gas carbon dioxide enrichment and trapping apparatus

Technical Field

The utility model relates to a cement kiln flue gas carbon dioxide enrichment and trapping apparatus.

Background

The greenhouse effect is currently receiving more and more global attention, and the combustion of fuel and the decomposition of raw meal during the cement production process can generate a large amount of CO₂The emission concentration of the coal-fired power plant boiler flue gas is even higher than that of the coal-fired power plant boiler flue gas, and the cement industry becomes the CO in China like the steel industry and the coal-fired power industry₂The main source of emissions.

Only about 21 percent of oxygen in common air participates in combustion, the rest 79 percent of nitrogen does not participate in combustion to form waste gas to take away a large amount of heat, and the oxygen-enriched combustion technology is a technology which adopts combustion-supporting gas with higher oxygen concentration than that in the air to combust, and even adopts pure oxygen to support combustion; the oxygen-enriched combustion technology is suitable for all fuels (gas, liquid and solid) and industrial boilers, and is widely applied to the fields of the steel industry and glass industrial kilns from the last 70 th century.

At present, the oxygen-enriched combustion technology is gradually applied in the limestone and cement industries, and the oxygen-enriched combustion technology is mainly applied in the cement industries for achieving the purposes of reducing coal consumption, improving the output of coal clinker per ton and reducing NO_xThe purpose of discharging.

In order to prevent kiln tail flue gas generated in the combustion process of cement raw materials from being directly discharged outwards, carbon dioxide in the kiln tail flue gas must be captured, and then the carbon dioxide is extracted in a separation and purification mode, such as a chemical absorption method and the like, because the content of the carbon dioxide in the cement kiln tail flue gas is not high, a large amount of waste flue gas needs to be processed to capture, separate and purify the carbon dioxide with a large quantity, a device with a large capacity needs to be configured to store the carbon dioxide, and the capture cost is overhigh; if the content or the concentration of carbon dioxide in the kiln tail flue gas is increased, the concentration of oxygen in the kiln can be reduced due to the fact that the concentration of the carbon dioxide is too high, oxygen-enriched combustion cannot be effectively conducted, decomposition of cement raw materials is not facilitated, and the purity of combustion products is low to be further improved.

SUMMERY OF THE UTILITY MODEL

To the current situation of above-mentioned prior art, the utility model aims to solve the technical problem that an oxygen content in the air of improving kiln system internal combustion is provided, and then is showing the cement kiln flue gas carbon dioxide enrichment and the trapping apparatus that has improved the carbon dioxide content in order to do benefit to the carbon dioxide entrapment in the exhaust flue gas from kiln tail system.

The utility model provides a technical scheme that above-mentioned technical problem adopted does: a cement kiln flue gas carbon dioxide enrichment and capture device comprises a kiln system and a raw material mill system, wherein the kiln system comprises a kiln tail system, a rotary kiln and a grate cooler which are sequentially connected along a material path; the air outlet of the kiln tail system and the air outlet of the low-temperature end of the grate cooler are both connected with the air inlet of the raw material mill system, and the kiln tail system is characterized in that: the kiln tail system is characterized by also comprising a dust collector, a carbon dioxide collecting and refining device and an oxygen generating device, wherein an air inlet of the dust collector is connected with an air outlet of the kiln tail system, an air inlet of the carbon dioxide collecting and refining device and an air inlet at the high-temperature end of the grate cooler are connected to the air outlet of the dust collector in parallel, and an air outlet of the oxygen generating device is connected with the air inlet at the high-temperature end of the grate cooler through a first pipeline; and a second pipeline is also inserted into the first pipeline, and an air supplementing valve is also arranged on the second pipeline.

Preferably, the air inlet of the dust collector and the air inlet of the raw material grinding system are both provided with a flue gas cooling device.

Compared with the prior art, the utility model has the advantages of: the utility model discloses let in pure oxygen or oxygen-enriched gas as make-up gas in to the kiln system with the help of oxygenerator to improve the oxygen content in the combustion air in the kiln system, and then form the flue gas that contains high concentration oxygen in the cold machine of comb and pass through the manifold cycles in the kiln system, thereby show and improve the carbon dioxide content in the flue gas of discharge in the kiln tail system, in order to do benefit to the entrapment of carbon dioxide entrapment refining plant to carbon dioxide.

Drawings

Fig. 1 is a schematic structural diagram of the present invention.

Detailed Description

Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by those of ordinary skill in the art to which the invention belongs. The use of "first," "second," and similar terms in the description herein do not denote any order, quantity, or importance, but rather the terms are used to distinguish one element from another. The word "comprising" or "comprises", and the like, means that the element or item listed before the word covers the element or item listed after the word and its equivalents, but does not exclude other elements or items. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

To maintain the following description of the embodiments of the present invention clear and concise, detailed descriptions of well-known functions and components may be omitted.

As shown in figure 1, the device for enriching and capturing carbon dioxide in flue gas of a cement kiln comprises a kiln system and a raw material grinding system, wherein the kiln system comprises a kiln tail system, a rotary kiln and a grate cooler which are sequentially connected along a material path; the air outlet of the kiln tail system and the air outlet of the low-temperature end of the grate cooler are both connected with the air inlet of the raw material mill system; the kiln tail system is characterized by also comprising a dust collector, a carbon dioxide collecting and refining device and an oxygen generating device, wherein an air inlet of the dust collector is connected with an air outlet of the kiln tail system, an air inlet of the carbon dioxide collecting and refining device and an air inlet at the high-temperature end of the grate cooler are connected to the air outlet of the dust collector in parallel, and an air outlet of the oxygen generating device is connected with the air inlet at the high-temperature end of the grate cooler through a first pipeline; the first pipeline is also spliced with a second pipeline, and the second pipeline is also provided with an air supplementing valve.

And the air inlet of the dust collector and the air inlet of the raw material grinding system are both provided with a flue gas cooling device.

The operation method comprises the following steps:

(1) the flue gas discharged from the kiln tail system is divided into two paths, wherein one path of flue gas is introduced into the high-temperature end of the grate cooler after being cooled by the flue gas cooling device and then being separated into powder by the dust collector; meanwhile, the oxygen generating device is used for preparing pure oxygen or oxygen-enriched gas and introducing the pure oxygen or oxygen-enriched gas into the high-temperature end of the grate cooler through a first pipeline; the two paths of gases are mixed with each other, and the oxygen content of the mixed gas is not lower than 21%.

(2) The mixed gas entering the high-temperature end of the grate cooler exchanges heat with the high-temperature clinker entering the grate cooler, the clinker is cooled, and meanwhile, the mixed gas rich in carbon dioxide and oxygen is heated and enters the rotary kiln and a kiln tail system respectively in the form of secondary air and tertiary air.

(3) After the kiln system operates for a period of time, the concentration of carbon dioxide in the flue gas discharged from the kiln tail system is gradually increased, and when the concentration of the carbon dioxide is increased to be more than or equal to 35%, part of the kiln tail flue gas from which the powder is separated by the dust collector is introduced into a carbon dioxide capture and purification device, so that capture and purification of the carbon dioxide are realized.

(4) And opening the air supplementing valve to ensure that the external normal-temperature air is also introduced into the high-temperature end of the grate cooler through the second pipeline and the first pipeline, so as to assist in adjusting the temperature and the oxygen content of the mixed gas.

The utility model discloses let in pure oxygen or oxygen-enriched gas as make-up gas in to the kiln system with the help of oxygenerator to improve the oxygen content in the combustion air in the kiln system, and then form the flue gas that contains high concentration oxygen in the cold machine of comb and pass through the manifold cycles in the kiln system, thereby show and improve the carbon dioxide content in the flue gas of discharge in the kiln tail system, in order to do benefit to the entrapment of carbon dioxide entrapment refining plant to carbon dioxide.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art that various changes in the embodiments and modifications thereof may be made, and equivalents may be substituted for elements thereof; such modifications and substitutions do not depart from the spirit and scope of the present invention in its corresponding aspects.

Claims

1. A cement kiln flue gas carbon dioxide enrichment and capture device comprises a kiln system and a raw material mill system, wherein the kiln system comprises a kiln tail system, a rotary kiln and a grate cooler which are sequentially connected along a material path; the air outlet of the kiln tail system and the air outlet of the low-temperature end of the grate cooler are both connected with the air inlet of the raw material mill system, and the kiln tail system is characterized in that: the kiln tail system is characterized by also comprising a dust collector, a carbon dioxide collecting and refining device and an oxygen generating device, wherein an air inlet of the dust collector is connected with an air outlet of the kiln tail system, an air inlet of the carbon dioxide collecting and refining device and an air inlet at the high-temperature end of the grate cooler are connected to the air outlet of the dust collector in parallel, and an air outlet of the oxygen generating device is connected with the air inlet at the high-temperature end of the grate cooler through a first pipeline; and a second pipeline is also inserted into the first pipeline, and an air supplementing valve is also arranged on the second pipeline.

2. The cement kiln flue gas carbon dioxide enrichment and capture device of claim 1, wherein: and the air inlet of the dust collector and the air inlet of the raw material grinding system are both provided with a flue gas cooling device.