Energy-saving carbon black production system and method

Abstract

The present invention provides an energy-saving carbon black production system and method. A high-efficiency heat exchange boiler is embedded between the quenching section and the gasification section of the carbon black reaction furnace, and the high-efficiency heat exchange boiler is used to reduce the temperature of the carbon black flue gas, thereby reducing the amount of quenching water, while making full use of the heat of the carbon black flue gas to achieve energy-saving effects.

Description

Technical Field

[0001] The present invention relates to the technical field of carbon black production, and in particular to a carbon black production system and a carbon black production method. Background Art

[0002] The furnace method is a common carbon black production method in the prior art, and generally adopts a carbon black production line consisting of a five-stage reactor, an air preheater, a waste heat boiler, a crude oil preheater, a bag filter and a carbon black refining system. When producing carbon black, the air preheated by the air preheater enters the reactor and is mixed with the fuel and then burned in the combustion section. The high-temperature gas of about 1950°C generated flows through the throat and enters the reaction section; the crude oil preheated by the crude oil preheater is sprayed in from the crude oil injection port set in the throat section, and enters the reaction section after being sheared and atomized by the high-temperature airflow flowing through the throat at a high speed at the throat, where it is cracked in the high-temperature gas to generate carbon black. The generated carbon black is suspended in the flue gas and flows to the quenching section; the flue gas with suspended carbon black is rapidly mixed with the primary quenching water supplied in the quenching section and flows to the gasification section, where the water absorbs the heat energy of the high-temperature flue gas and vaporizes it. The flue gas is rapidly cooled down to make the carbon black tail gas cool to below 1000℃ (this temperature is the primary quenching temperature); the reaction of carbon black is terminated; the flue gas with suspended carbon black after being cooled to below 1000℃ enters the air preheater, waste heat boiler and crude oil preheater in turn for heat exchange, the flue gas with suspended carbon black is continuously cooled, and is controlled at about 280℃ by secondary quenching water to enter the bag filter for separation of carbon black and flue gas; the separated carbon black enters the rear carbon black refining system, and the flue gas (the carbon black industry calls the flue gas after the carbon black is separated tail gas) is sent to the tail gas boiler for combustion to produce steam for steam turbine power generation.

[0003] In the existing carbon black production technology, although air preheaters, waste heat boilers, crude oil preheaters and other online waste heat utilization energy-saving devices are used, a large amount of quenching water is still used to cool the carbon black flue gas at the end of the carbon black reaction. Moreover, under the constraints of the existing process technology, the carbon black flue gas needs to be cooled to below 1000°C before entering the air preheater, which wastes this part of the heat and consumes a large amount of water resources. Summary of the invention

[0004] In order to save energy consumed in the process of carbon black production, the present invention provides an energy-saving carbon black production system and method.

[0005] A first aspect of the present invention provides an energy-saving carbon black production system, comprising:

[0006] A carbon black reactor, comprising a combustion section, a throat section, a reaction section, a quenching section and a gasification section;

[0007] A high-efficiency heat exchange boiler, wherein the high-efficiency heat exchange boiler is embedded between the quenching section and the gasification section of the carbon black reactor, wherein the heat source inlet of the high-efficiency heat exchange boiler is connected to the quenching section of the carbon black reactor, and the heat source outlet of the high-efficiency heat exchanger is connected to the gasification section of the carbon black reactor;

[0008] An air preheater, wherein a heat source inlet of the air preheater is connected to the gasification section of the carbon black reactor;

[0009] A steam superheater, wherein the heat source inlet of the steam superheater is connected to the heat source outlet of the air preheater, and the cold source inlet of the steam superheater is connected to the cold source outlet of the high-efficiency heat exchange boiler;

[0010] A waste heat boiler, wherein a heat source inlet of the waste heat boiler is connected to a heat source outlet of the steam superheater via a pipeline;

[0011] A raw oil preheater, wherein a heat source inlet of the raw oil preheater is connected to a heat source outlet of the waste heat boiler through a pipeline;

[0012] Among them, the air outlet of the air preheater is connected to the air inlet of the carbon black reactor through a pipeline, and the crude oil outlet of the crude oil preheater is connected to the crude oil injection inlet arranged in the throat section of the carbon black reactor through a pipeline.

[0013] Furthermore, the heat source outlet of the crude oil preheater is connected to a pipeline, and the pipeline is provided with a secondary quenching water inlet.

[0014] A second aspect of the present invention provides an energy-saving carbon black production method, which adopts the above-mentioned energy-saving carbon black production system and comprises the following steps:

[0015] Inputting fuel and air into the carbon black reaction furnace, causing the fuel and air to burn in the combustion section to generate high-temperature flue gas;

[0016] Inputting crude oil into the throat section, causing the crude oil to undergo a cracking reaction at high temperature to generate carbon black smoke;

[0017] Inputting primary quenching water into the quenching section to cool the carbon black flue gas, and controlling the amount of the primary quenching water so that the temperature of the carbon black flue gas is controlled to be above 1000° C.;

[0018] The carbon black flue gas is passed through a high-efficiency heat exchange boiler and exchanges heat with a cold source, so that the temperature of the carbon black flue gas is reduced to below 1000° C.;

[0019] The carbon black flue gas whose temperature is reduced to below 1000° C. is sequentially passed through an air preheater, a steam superheater, a waste heat boiler and a crude oil preheater;

[0020] Among them, the air input into the carbon black reaction furnace is the air preheated by the air preheater, and the raw oil input into the throat section is the raw oil preheated by the raw oil preheater.

[0021] Furthermore, by controlling the amount of primary quenching water, the temperature of the carbon black flue gas is made to be above 1000°C. This temperature is a non-set temperature and changes with the amount of primary quenching water. The primary quenching temperature is a set value, and the primary quenching water amount is interlocked with the primary quenching temperature. The primary quenching water amount is automatically controlled by a microcomputer as the primary quenching temperature changes.

[0022] Furthermore, the temperature of the carbon black flue gas after passing through the high-efficiency heat exchange boiler and exchanging heat with the cold source is reduced to 980±10°C (primary quenching temperature, which is the set temperature).

[0023] Furthermore, the cold source of the high-efficiency heat exchange boiler is water.

[0024] The present invention has the following beneficial effects:

[0025] 1. Using high-efficiency heat exchange boilers to quickly reduce the temperature of carbon black flue gas can save a large amount of quenching water required for carbon black production, thus saving water resources;

[0026] 2. Rapid cooling water cools the carbon black flue gas after gasification. Due to the reduction of the amount of rapid cooling water, the water content in the carbon black flue gas (tail gas) is reduced, the concentration of combustible components in the tail gas is increased, and the combustion calorific value of the tail gas is increased, so that the thermal efficiency of the tail gas boiler is improved, and the steam production and power generation are increased;

[0027] 3. Due to the reduction of a large amount of quenching water, the amount of carbon black smoke is reduced, the load of the bag filter is reduced, the filtering effect of the bag filter is improved, and the service life of the bag filter is extended;

[0028] 4. High-efficiency heat exchange boilers can produce a large amount of saturated steam, which is then heated to superheated steam and used in the steam system of steam turbine generators to increase power generation. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a structural schematic diagram of an energy-saving carbon black production system of the present invention.

[0030] Figure 2 The present invention is a schematic flow chart of an energy-saving carbon black production method.

[0031] Explanation of the accompanying drawings: 1. Combustion section, 2. Throat section, 3. Reaction section, 4. Rapid cooling section, 5. High-efficiency heat exchange boiler, 6. Gasification section, 7. Air preheater, 8. Steam superheater, 9. Waste heat boiler, 10. Crude oil preheater, 11. Fuel inlet, 12. Air duct, 13. Steam duct, 14. Superheated steam duct, 15. First flue gas duct, 16. Second flue gas duct, 17. Third flue gas duct, 18. Secondary rapid cooling water inlet, 19. Primary rapid cooling water inlet, 20. Crude oil pipeline, 21. Crude oil inlet. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] Unless otherwise defined, the technical or scientific terms used herein shall have the usual meanings understood by persons of ordinary skill in the field to which the invention belongs. The words "first", "second" and similar terms used in the specification and claims of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "one" or "an" do not indicate a quantity limitation, but indicate the existence of at least one. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship also changes accordingly. The thickness and shape of each film layer in the accompanying drawings do not reflect the actual proportions, and the purpose is only to illustrate the contents of the present invention.

[0034] like Figure 1 As shown, an energy-saving carbon black production system includes a carbon black reaction furnace, a high-efficiency heat exchange boiler 5, an air preheater 7, a steam superheater 8, a waste heat boiler 9 and a raw oil preheater 10.

[0035] The carbon black reactor comprises a combustion section 1, a throat section 2, a reaction section 3, a quenching section 4 and a gasification section 6. The combustion section 1, the throat section 2, the reaction section 3 and the quenching section 4 are connected in sequence by flanges. The combustion section 1 is provided with a fuel inlet 11, and the quenching section 4 is provided with a primary quenching water inlet 19. The high-efficiency heat exchange boiler 5 is embedded between the quenching section 4 and the gasification section 6 of the carbon black reactor and connected by flanges. The heat source inlet of the high-efficiency heat exchange boiler 5 is connected to the quenching section 4 of the carbon black reactor, and the heat source outlet of the high-efficiency heat exchange boiler 5 is connected to the gasification section 6 of the carbon black reactor. The cold source outlet of the high-efficiency heat exchange boiler 5 is connected to the cold source inlet of the steam superheater 8 through a pipeline 13. The heat source inlet of the air preheater 7 is connected to the gasification section 6 of the carbon black reactor through a flange, and the air outlet of the air preheater 7 is connected to the air inlet of the carbon black reactor through a pipeline 12. The heat source inlet of the steam superheater 8 is connected to the heat source outlet of the air preheater 7 through a flange, and the heat source outlet of the steam superheater 8 is connected to the heat source inlet of the waste heat boiler 9 through a pipeline 15. The cold source inlet of the steam superheater 8 is connected to the cold source outlet of the high-efficiency heat exchange boiler 5 through a pipeline 13, and the cold source outlet of the steam superheater 8 is connected to a pipeline 14, and the other end of the pipeline 14 is connected to the steam power generation system. The heat source inlet of the raw oil preheater 10 is connected to the heat source outlet of the waste heat boiler 9 through a pipeline 16, and the raw oil outlet of the raw oil preheater 10 is connected to the raw oil injection inlet set in the throat section 2 of the carbon black reactor through a pipeline 20. The heat source outlet of the raw oil preheater 10 is connected to a pipeline 17, and the other end of the pipeline 17 is connected to a carbon black collection system (bag filter). A secondary quenching water inlet 18 is provided on the pipeline 17, and quenching water can be sprayed into it to further cool the carbon black flue gas.

[0036] In the above embodiments, the carbon black reaction furnace, high-efficiency heat exchange boiler, air preheater, steam superheater, waste heat boiler and crude oil preheater are all commonly used equipment in the prior art. Among them, the high-efficiency heat exchange boiler, air preheater, superheater, waste heat boiler and crude oil preheater can all achieve heat exchange. During heat exchange, the heat-absorbing medium is called a cold source, and the heat-releasing medium is called a heat source. In the carbon black production process, the heat source is carbon black flue gas, the cold source in the high-efficiency heat exchange boiler, steam superheater and waste heat boiler is water, the cold source in the air preheater is air, and the cold source in the crude oil preheater is crude oil.

[0037] like Figure 2 As shown, when using the energy-saving carbon black production system of the present invention to produce carbon black, the following steps can be followed:

[0038] S1, inputting fuel and air into the carbon black reactor (fuel is inputted from the axial fuel inlet 11, and air is inputted from the radial air inlet), so that the fuel and air burn in the combustion section 1 to generate high temperature (about 1950° C.);

[0039] S2, inputting crude oil into the throat section 2, so that the crude oil undergoes a cracking reaction at high temperature to generate carbon black flue gas;

[0040] S3, inputting quenching water into the quenching section 4 to cool the carbon black flue gas, and controlling the amount of quenching water so that the temperature of the carbon black flue gas is above 1000° C.;

[0041] S4, passing the carbon black flue gas through a high-efficiency heat exchange boiler 5 and exchanging heat with a cold source (water), so that the temperature of the carbon black flue gas is reduced to 980° C. (an error of 10° C. is allowed);

[0042] S5, the carbon black flue gas whose temperature is reduced to 980° C. is sequentially passed through an air preheater 7, a steam superheater 8, a waste heat boiler 9 and a crude oil preheater 10;

[0043] Among them, the air in S1 is preheated by the air preheater 7, and the crude oil in S2 is preheated by the crude oil preheater 10.

[0044] In the high-efficiency heat exchange boiler 5, the carbon black flue gas exchanges heat with water, the temperature of the water increases and saturated steam is generated, and the generated saturated steam enters the steam superheater 8 through the pipeline 13. In the steam superheater 8, the carbon black flue gas exchanges heat with saturated steam, the temperature of the saturated steam increases and becomes superheated steam, and the superheated steam can be transported to the steam power generation system through the pipeline 14. In the air preheater 7, the carbon black flue gas exchanges heat with air, the air temperature increases, and the high-temperature air is sent to the combustion section 1 of the carbon black reactor. In the waste heat boiler 9, the carbon black flue gas exchanges heat with water, the temperature of the water increases and vaporizes into steam. In the crude oil preheater 10, the carbon black flue gas exchanges heat with the crude oil, the temperature of the crude oil increases, and the heated crude oil is sent to the throat section 2 of the carbon black reactor. After multiple heat exchanges, the temperature of the carbon black flue gas is relatively low and can be transported to the carbon black collection system by the pipeline 17.

[0045] Compared with the carbon black reactors of the same level in the industry, the carbon black reactor with a designed comprehensive production capacity of 40,000 tons / year is used to produce the same type of N326 carbon black, and the data in Table 1 are obtained.

[0046] Table 1

[0047]

[0048] From the above data, it can be seen that under similar reaction conditions of air volume, air temperature, raw oil volume and raw oil temperature, the carbon black reactor equipped with high-efficiency heat exchange boiler has 1720kg / h less primary quenching water than that without high-efficiency heat exchange boiler. The role of this part of primary quenching water in reducing the temperature of carbon black flue gas is completed by the high-efficiency heat exchange boiler. The high-efficiency heat exchange boiler produces 4500kg / h of steam per hour. From 20℃ water to steam generation, the heat energy that can be recovered per hour is converted into about 430kg of standard coal.

[0049] The present invention adds a high-efficiency heat exchange boiler between the quenching section and the gasification section of the original carbon black production line, retains the quenching section, and is used to control the temperature of the carbon black flue gas entering the air preheater after passing through the high-efficiency heat exchange boiler, and to prevent the high-efficiency heat exchange boiler from overheating and burning when a failure occurs. After the high-temperature carbon black flue gas from the reaction section of the carbon black reactor enters the high-efficiency heat exchange boiler, it quickly exchanges heat with the cold medium (water) in the high-efficiency heat exchange boiler. The high-efficiency heat exchange boiler generates a large amount of saturated steam, and the temperature of the carbon black flue gas decreases rapidly, which can reduce the amount of quenching water used in the quenching section. A steam superheater is added to the outlet of the air preheater. The saturated steam generated by the high-efficiency heat exchange boiler is heated to superheated steam by the sub-high-temperature flue gas coming out of the air preheater through the superheater, and the superheated steam is incorporated into the steam system of tail gas power generation.

[0050] The carbon black produced is of different varieties and outputs, and the flue gas volume and temperature passing through the reaction section are also different, so the flue gas temperature coming out of the high-efficiency heat exchange boiler is also different. In the quenching section, a small amount of water is used to adjust and control the flue gas temperature entering the air preheater to ensure that the temperature of the air preheated by the air preheater is not affected. The temperature of the preheated air is stable to ensure the stability of the carbon black production process and product quality.

[0051] The above implementation modes are only used to illustrate the present invention, but not to limit the present invention. Ordinary technicians in the relevant technical field may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions also belong to the scope of the present invention. The protection scope of the present invention should be defined by the claims.

Claims

1. An energy-saving carbon black production system, comprising: A carbon black reactor, comprising a combustion section, a throat section, a reaction section, a quenching section and a gasification section; A high-efficiency heat exchange boiler, wherein the high-efficiency heat exchange boiler is embedded between the quenching section and the gasification section of the carbon black reactor, wherein the heat source inlet of the high-efficiency heat exchange boiler is connected to the quenching section of the carbon black reactor, and the heat source outlet of the high-efficiency heat exchange boiler is connected to the gasification section of the carbon black reactor; An air preheater, wherein a heat source inlet of the air preheater is connected to the gasification section of the carbon black reactor; A steam superheater, wherein the heat source inlet of the steam superheater is connected to the heat source outlet of the air preheater, and the cold source inlet of the steam superheater is connected to the cold source outlet of the high-efficiency heat exchange boiler; A waste heat boiler, wherein a heat source inlet of the waste heat boiler is connected to a heat source outlet of the steam superheater via a pipeline; A raw oil preheater, wherein a heat source inlet of the raw oil preheater is connected to a heat source outlet of the waste heat boiler through a pipeline; The hot air outlet of the air preheater is connected to the air inlet of the carbon black reactor through a pipeline, and the raw oil outlet of the raw oil preheater is connected to the raw oil injection inlet arranged at the throat section of the carbon black reactor through a pipeline; The heat source outlet of the crude oil preheater is connected to a pipeline, and the pipeline is provided with a secondary quenching water inlet; Inputting fuel and air into the carbon black reaction furnace, causing the fuel and air to burn in the combustion section to generate high-temperature flue gas; Inputting crude oil into the throat section, causing the crude oil to undergo a cracking reaction at high temperature to generate carbon black smoke; Inputting primary quenching water into the quenching section to cool the carbon black flue gas, and controlling the amount of primary quenching water to keep the temperature of the carbon black flue gas above 1000° C.; The carbon black flue gas is passed through a high-efficiency heat exchange boiler and exchanges heat with a cold source, so that the temperature of the carbon black flue gas is reduced to below 1000° C.; The carbon black flue gas whose temperature is reduced to below 1000° C. is sequentially passed through an air preheater, a waste heat boiler and a feed oil preheater; Wherein, the air input into the carbon black reaction furnace is the air preheated by the air preheater, and the raw oil input into the throat section is the raw oil preheated by the raw oil preheater; By controlling the amount of primary quenching water, the temperature of the carbon black flue gas is controlled to be above 1000°C. The temperature at this point is not a set temperature and changes with the amount of primary quenching water. The primary quenching temperature is a set value. The amount of primary quenching water is interlocked with the primary quenching temperature. The amount of primary quenching water is automatically controlled by a microcomputer as the primary quenching temperature changes. The temperature of the carbon black flue gas after passing through the high-efficiency heat exchange boiler and exchanging heat with the cold source is reduced to 980±10°C; The cold source of the high-efficiency heat exchange boiler is water.

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