Liquid combustion improver adding pipe group of petroleum coke reaction circulating gas inlet system in calcining furnace

Abstract

The utility model discloses a liquid combustion improver adding pipe group of a petroleum coke reaction circulating air inlet system in a calcining furnace, and mainly relates to carbon production. Comprising a jet device assembly and a connecting pipeline connected with the jet device assembly. The jet device assembly comprises a jet device pipeline and a combustion improver adding port communicated with the outer wall of the jet device pipeline; the connecting pipeline is located in the furnace body, and the tail end of the connecting pipeline is connected with a flow guide cover. The liquid combustion improver adding device has the advantages that the liquid combustion improver adding device is used for adding liquid combustion improvers into the calcining furnace body and can add the liquid combustion improvers into the furnace body in an atomized mode, so that the combustion improvers and the combustion improvers in the furnace body are combined more sufficiently, and energy waste of the combustion improvers and fuel is avoided; and the liquid combustion improver is added in this way, so that the temperature change in the furnace body is stable, and the addition amount of the liquid combustion improver is convenient to control.

Description

Technical Field

[0001] The utility model relates to the field of carbon production, in particular to a liquid combustion-supporting agent adding pipe group of a petroleum coke reaction circulation air intake system in a calcining furnace. Background Art

[0002] The statements in this section merely provide background technical information related to the present invention and do not necessarily constitute prior art.

[0003] In the electrolytic aluminum industry, carbon blocks are usually used as anodes. Anode carbon blocks are made of petroleum coke as aggregate and coal tar as binder, and are used as anode materials for pre-baked aluminum electrolytic cells. In the process of producing anode carbon blocks, the raw petroleum coke is first calcined. Calcination is a pretreatment process for carbon production. During the calcination process, petroleum coke will undergo a series of significant changes from elemental composition to organizational structure. Because petroleum coke contains volatiles, it needs to be calcined to remove moisture and volatiles from the raw materials, so that the volume of the carbon raw materials can be fully shrunk and its thermal stability and physical and chemical properties can be improved. During calcination, the molecular structure changes continuously with the discharge of volatiles, and the volume of the raw materials themselves gradually shrinks, thereby increasing the density and mechanical strength of the raw materials and reducing the resistivity of the calcined petroleum coke. If the volatiles of the raw materials are too high, the petroleum coke will shrink too much during the subsequent roasting process, resulting in structural deformation, and ultimately making the anode carbon blocks very easy to break after forming, so it is necessary to discharge the volatiles in the raw materials. During calcination, the calcination temperature affects the conductivity of the calcined petroleum coke product. Calcination causes the molecular structure of the petroleum coke to change continuously, and the volatile matter to escape continuously, making the resistivity of the petroleum coke the lowest. As the calcination temperature increases, the impurities contained in the carbon raw materials are gradually eliminated, reducing the chemical activity of the raw materials, thereby improving the conductivity of the raw materials.

[0004] The existing calcined petroleum coke production method generally calcines petroleum coke in a calcining furnace. Most of the existing calcining furnaces control the calcination temperature in the furnace by the oxygen intake at the air inlet. When heating, the air inlet gates on the outside of the calcining furnace body need to be manually opened, and air enters the calcining furnace through the air inlet, so that the oxygen intake in the calcining furnace is rapidly increased. However, in this method, during the heating stage of calcining petroleum coke, all the air inlet gates need to be opened, and the oxygen content in the furnace body is increased by natural wind, which makes the heating of the furnace body slow. Therefore, the oxygen content in the furnace body can only be increased by multiple air inlets on each furnace body to achieve the effect of combustion-supporting. However, when calcining petroleum coke, dozens of furnace bodies are generally used for calcination at the same time, and each furnace body has three air inlets. When heating, the air inlet gates on each furnace body need to be fully opened. Manual control is labor-intensive and the temperature increase effect is slow. When the furnace body is heated, since the air inlet is natural wind, there is a large temperature difference between the natural wind and the inside and outside of the furnace body. The large temperature difference between the inside and outside of the furnace body will cause frequent thermal expansion and contraction of the calcining furnace body wall, and eventually cause the outer wall of the calcining furnace to crack, which directly shortens the life of the furnace body and increases the cost investment of the factory.

[0005] In order to reduce the impact of multiple air inlets on the furnace body on the life of the furnace body, the following improvements are made: the multiple air inlets on each furnace body are reduced to a single one. After the air inlet on the furnace body is improved to a single one, in order to meet the temperature requirements of different calcination stages of petroleum coke, it is necessary to add combustion aids into the furnace body. When adding liquid combustion aids into the furnace body, if the liquid combustion aid enters the calcination furnace body in a liquid state, once the amount added is too large, the combustion aid effect will be insufficient, and after entering the furnace body in a liquid state, the amount of combustion aid added is not easy to control, and too much added at one time will cause the temperature inside the furnace body to rise suddenly, resulting in fluctuations in the temperature change inside the furnace body, thereby affecting the calcination effect of the carbon blocks inside the furnace body. Utility Model Content

[0006] The utility model aims to provide a liquid combustion aid adding pipe group of a petroleum coke reaction circulation air intake system in a calcining furnace, which is used to add liquid combustion aid to the inside of the calcining furnace body, and can add the liquid combustion aid to the inside of the furnace body in an atomized form, so that the combustion aid and the combustion aid inside the furnace body are more fully combined, avoiding energy waste of the combustion aid and fuel, and adding the liquid combustion aid in this way makes the temperature change inside the furnace body stable, and it is convenient to control the amount of liquid combustion aid added.

[0007] In order to achieve the above purpose, the utility model is implemented through the following technical solutions:

[0008] The liquid combustion-aid adding pipe group of the petroleum coke reaction circulation air intake system in the calcining furnace includes an ejector assembly and a connecting pipeline connected to the ejector assembly; the ejector assembly includes an ejector pipe and an combustion-aid adding port connected to the outer wall of the ejector pipe; the connecting pipe is located in the furnace body, and a flow guide cover is connected to the end of the connecting pipe.

[0009] The ejector assembly also includes an air inlet arranged at one end of the ejector pipe, a nozzle arranged at the air inlet, an intake chamber arranged between the nozzle and the combustion-aiding agent addition port, and a tapered section arranged between the intake chamber and the connecting pipeline; the connecting pipeline and the nozzle are both located in the furnace body, and the guide cover of the connecting pipeline is provided with a pressure diffuser section, and the cross-section of the pressure diffuser section is larger than that of the tapered section.

[0010] Compared with the prior art, the beneficial effects of the present invention are:

[0011] It is used to add liquid combustion aid into the calcining furnace body, and can add the liquid combustion aid into the furnace body in an atomized form, so that the combustion aid can be more fully combined with the combustion aid inside the furnace body, avoiding energy waste of the combustion aid and fuel, and adding the liquid combustion aid in this way makes the temperature change inside the furnace body stable, and it is easy to control the amount of liquid combustion aid added. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Attached Figure 1 This is an overall view of the calcining workshop of the utility model.

[0013] Attached Figure 2 This is a pipeline connection view of the calcining workshop in the utility model.

[0014] Attached Figure 3 It is a cross-sectional view of the ejector assembly in the utility model.

[0015] Attached Figure 4 It is an internal diagram of the ejector assembly in the utility model.

[0016] Attached Figure 5 It is an overall view of the device in the utility model.

[0017] Attached Figure 6 It is an internal sectional view of the device in the utility model.

[0018] Numbers shown in the accompanying drawings:

[0019] 1. Connecting pipeline; 2. Ejector pipeline; 3. Combustion-supporting agent adding port; 4. Furnace body; 5. Flow guide cover; 6. Nozzle; 7. Suction chamber; 8. Gradually contracting section; 9. Diffuser section; 10. Air inlet pipeline; 11. Flow rate control device. DETAILED DESCRIPTION

[0020] The present invention is further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope defined by the present application.

[0021] The utility model discloses a liquid combustion-supporting agent adding pipe group of a petroleum coke reaction circulation air intake system in a calcining furnace. Before describing the process, a workshop for calcining petroleum coke is briefly described. Since the ventilation openings of the furnace body 4 are reduced and the air intake volume needs to be further increased, a pulse bag dust removal device is arranged in the calcining workshop to filter the waste gas such as dust generated by crushing and calcining the petroleum coke. The dust-containing gas enters the dust collector under the gravitational effect of the induced draft fan, and the large particles of dust in the gas are filtered under the action of gravity. The fine dust adheres to the outer surface of the bag under the filtering effect of the bag. After filtering, the bag is cleaned of dust by a pressurized pulse air cannon, so that the dust in the filter hole of the bag falls off, and the purified gas passes through the bag and is directly discharged into the atmosphere through the ventilation duct. This dust removal method has disadvantages. The bags of the pulse bag dust removal equipment need to be replaced regularly. Once the bags are broken or the filtering effect deteriorates, if the smoke is not discovered in time, it will be directly discharged into the atmosphere, affecting the environment in the atmosphere and causing an increase in PM2.5 in the environment. Because the gas passing through the pulse dust removal equipment is continuously transported by the induced draft fan, it is finally discharged into the atmosphere after dust removal. Combined with the content of the improvement of the furnace body 4 described in the background technology, because the reduction of the air inlet on the furnace body 4 will lead to a reduction in the amount of oxygen entering the furnace body 4, and the air inlet on the furnace body 4 is all natural wind, which will cause the temperature in the furnace body 4 to rise slowly and fail to reach a specific temperature. Therefore, the gas discharged from the ventilation duct of the pulse bag dust removal equipment is combined with the air inlet pipeline 10 of the circulating air intake system. The air inlet pipeline 10 is provided with a plurality of ejector assemblies and a connecting pipeline 1. One end of the connecting pipeline 1 of the ejector assembly is connected to the air inlet pipeline 10, and the other end is connected to the connecting pipeline 1.

[0022] First, the ejector assembly is described: the ejector is based on the Venturi effect, and low pressure is generated near the high-speed flowing fluid, thereby generating an adsorption effect. The ejector assembly includes an ejector pipe 2, a nozzle 6 connected to the air inlet pipeline 10, an air inlet provided at one end of the ejector pipe 2, and an oxidant addition port 3 connected to the outer wall of the ejector pipe 2;

[0023] A nozzle 6 is provided at the air inlet, a suction chamber 7 is provided between the nozzle 6 and the combustion-supporting agent addition port 3, a tapered section 8 is provided between the suction chamber 7 and the connecting pipeline 1; the connecting pipeline 1 and the nozzle 6 are both located in the furnace body 4, a diffuser section 9 is provided in the connecting pipeline 1, and the cross section of the diffuser section 9 is larger than that of the tapered section 8. Figure 3 and Figure 4As shown, air is taken in through a nozzle 6 with a small cross-sectional area, so that the flow rate of the gas is accelerated, thereby reducing the pressure in the suction chamber 7 to be lower than the external atmospheric pressure, so that the combustion aid at the combustion aid addition port 3 allows the liquid combustion aid to enter the suction chamber 7 through the negative pressure and mix with the gas entering from the air inlet pipe 10. After the combustion aid and the gas are mixed, they pass through the tapered section 8 into the diffuser section 9 of the guide cover 5, and then directly enter the furnace body 4 from the diffuser section 9. For the ejector assembly, a flow rate control device 11 can be set at the nozzle 6. By changing the cross-sectional size of the nozzle 6, the flow rate at the air inlet is determined, and the amount of liquid combustion aid added is controlled.

[0024] When the combustion aid is a liquid, such as a methanol fuel combustion aid, etc., it is different from other combustion aids in that: the liquid combustion aid has a greater impact on the temperature inside the furnace body 4. Since the temperature difference between the inside and outside of the furnace body 4 is too large, it is necessary to reduce the impact of the liquid combustion aid on the temperature inside the furnace body 4 as much as possible, and avoid the instability of the temperature inside the furnace body 4 due to incomplete combustion of the liquid combustion aid after the liquid combustion aid flows into the furnace body 4 in the form of water flow, thereby affecting the quality of the carbon block product. Therefore, when the liquid combustion aid needs to enter the furnace body 4, it enters the furnace body 4 in the form of atomization. First, the liquid combustion aid enters the suction chamber 7 from the combustion aid addition port 3 in the form of liquid, and then enters the tapered section 8 from the suction chamber 7, and then enters the furnace body 4 in the form of atomization, so that the combustion aid and the fuel are more fully combined, thereby stabilizing the temperature inside the furnace body 4.

[0025] For the atomization process of liquid combustion aid, as shown in the attached figure of the specification Figure 5 and Figure 6 As shown, the cross-sectional area of ​​the nozzle 6 mentioned above becomes smaller, so the flow rate in the suction chamber 7 is accelerated, and in the form of negative pressure. The liquid combustion aid combines with the gas in the air inlet pipe 10 and enters the tapered section 8 from the suction chamber 7 until entering the diffuser section 9 of the guide cover 5. The liquid combustion aid and the gas in the air inlet pipe 10 are in the form of high-speed jets. At the same time, the gas in the air inlet pipe 10 shears the liquid combustion aid into droplets, and then enters the furnace body 4 in the form of atomization. As for the degree of liquid atomization, it can be controlled by controlling the gas flow rate of the air inlet pipe 10, and the amount of liquid combustion aid added can also be controlled.

[0026] The above is only explained in the form of the combustion aid adding port 3. For the combustion aid adding process, it is necessary to ensure that the internal pressure of the container containing the combustion aid is sufficient to meet the requirements of the ejector assembly to deliver the gas into the furnace body 4, and the gas pressure balance is required, and the control assembly is also required to control the connection between the container containing the combustion aid and the ejector assembly. The above content does not belong to the main invention of this application, and the above content is known to those skilled in the art.

[0027] To sum up, the present device is used to add liquid combustion aid to the inside of the calcining furnace body 4, and can add the liquid combustion aid to the inside of the furnace body 4 in an atomized form, so that the combustion aid can be more fully combined with the combustion aid inside the furnace body 4, avoiding energy waste of the combustion aid and fuel, and adding the liquid combustion aid in this way makes the temperature change inside the furnace body 4 stable, and it is easy to control the amount of liquid combustion aid added.

Claims

1. A liquid combustion-supporting agent adding pipe group for the petroleum coke reaction cycle air intake system in a calcining furnace, characterized in that: It comprises an ejector assembly and a connecting pipeline (1) connected to the ejector assembly; The ejector assembly comprises an ejector pipe (2) and an oxidant addition port (3) connected to the outer wall of the ejector pipe (2); The connecting pipeline (1) is located in the furnace body (4), and a flow guide cover (5) is connected to the end of the connecting pipeline (1).

2. According to claim 1, the liquid combustion-supporting agent adding pipe group of the petroleum coke reaction cycle air intake system in the calcining furnace is characterized in that: The ejector assembly further comprises an air inlet arranged at one end of the ejector pipe (2), a nozzle (6) arranged at the air inlet, an intake chamber (7) arranged between the nozzle (6) and the combustion-supporting agent addition port (3), and a tapered section (8) arranged between the intake chamber (7) and the connecting pipeline (1); The connecting pipeline (1) and the nozzle (6) are both located in the furnace body (4); the flow guide cover (5) of the connecting pipeline (1) is provided with a diffuser section (9); and the cross section of the diffuser section (9) is larger than that of the tapered section (8).

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