A production process of low-sulfur petroleum coke

Abstract

The present invention belongs to the technical field of petroleum coke desulfurization, and particularly relates to a production process of low-sulfur petroleum coke. An alkali solution and high-sulfur petroleum coke are added to a high-pressure mixing treatment device, and after activation treatment, an activated material is obtained; then a catalyst and an oxidant are added to the high-pressure mixing treatment device, mixed uniformly with the activated material, and after oxidation treatment, a slurry is obtained; the slurry is filtered, dried, and subjected to gradient calcination by combining low-temperature calcination and high-temperature short-time calcination to obtain low-sulfur petroleum coke. The solution of the present invention improves both the desulfurization efficiency and desulfurization effect, reduces the requirements for equipment, saves energy, and reduces production costs by making the activation and catalytic oxidation processes proceed continuously in the high-pressure mixing treatment device and by controlling the time and stages of high-temperature calcination.

Description

Technical Field

[0001] The present invention belongs to the technical field of petroleum coke desulfurization, and particularly relates to a production process of low-sulfur petroleum coke. Background Art

[0002] In recent years, with the development of industry, the demand for petroleum has been increasing day by day. Along with it, the output of petroleum derivatives such as vacuum residue has been increasing, especially high-sulfur petroleum coke. As a highly polluting product, the use of high-sulfur petroleum coke is restricted, while the demand for low-sulfur petroleum coke in the electrolytic aluminum industry has increased significantly. Therefore, it is necessary to desulfurize high-sulfur petroleum coke to meet environmental protection requirements and avoid waste of resources.

[0003] Currently, the main petroleum coke desulfurization technologies include high-temperature calcination desulfurization, chemical oxidation desulfurization, and microbial desulfurization. Among them, high-temperature calcination desulfurization is the most widely used desulfurization method for high-sulfur petroleum coke at present. However, when relying solely on high-temperature thermal desulfurization, the requirement for the combustion temperature is very high. Only when the calcination temperature reaches 1600 °C can there be a relatively high desulfurization rate, resulting in high requirements for equipment materials. Especially when the calcination furnace maintains high-temperature operation for a long time, the refractory materials in the furnace inner liner need to be frequently maintained and replaced.

[0004] CN111675206B discloses a desulfurization process for high-sulfur petroleum coke. First, the petroleum coke is subjected to alkali leaching activation treatment under high-pressure conditions, and then the organic sulfur in the petroleum coke is oxidized, and then calcination treatment is carried out under low-temperature conditions, avoiding the long-term high-temperature operation of the calcination furnace. However, through production verification, on the one hand, simple low-temperature calcination cannot effectively improve the sulfur removal efficiency, and on the other hand, the desulfurization rate has not reached the expected requirements. In addition, since there are many steps and energy consumption in the chemical activation link in the early stage of calcination in this process, there is no reference in the industry on how to carry out full-process process control efficiently and at low cost. Summary of the Invention

[0005] To solve the problems raised in the background art, the present invention provides a production process of low-sulfur petroleum coke.

[0006] The technical solution of the present invention is as follows:

[0007] The present invention provides a production process of low-sulfur petroleum coke, including the following steps:

[0008] (1) Add an alkali solution and high-sulfur petroleum coke to a high-pressure mixing treatment device, mix evenly, carry out activation treatment, filter out the moisture and dry at 90 °C - 120 °C to obtain an activated material;

[0009] (2) Add a catalyst and an oxidant to the high-pressure mixing treatment device, mix evenly with the activated material, and carry out oxidation treatment at 80 °C - 130 °C to obtain a slurry;

[0010] (3) Filter the slurry, dry it, and then calcine it to obtain low-sulfur petroleum coke;

[0011] For the said calcination, a method combining low-temperature calcination and high-temperature short-time calcination is adopted. For the low-temperature calcination, the temperature is 450°C - 700°C, and the heat preservation time is 60 - 120 min; for the high-temperature short-time calcination, the temperature is 950°C - 1200°C, and the heat preservation time is 2 - 6 min.

[0012] Furthermore, for the production process of the low-sulfur petroleum coke as described above, the activated material obtained in step (1) is specifically obtained by adding a Ca(OH)₂ solution and high-sulfur petroleum coke to a high-pressure mixing treatment device, mixing evenly, carrying out activation treatment at a temperature of 60°C - 100°C and a pressure of 30 - 60 MPa for 2 - 6 h, and then drying at 90°C - 120°C;

[0013] The slurry obtained in step (2) is specifically

[0014] adding a catalyst composed of metal compounds and an oxidant mainly composed of nitric acid to the high-pressure mixing treatment device, mixing evenly with the activated material, and carrying out oxidation treatment at 80°C - 130°C for 5 - 9 h;

[0015] The low-sulfur petroleum coke obtained in step (3) is specifically

[0016] filter the slurry, dry it, and then calcine it in three stages,

[0017] First stage: Raise the temperature of the calcination furnace to 950°C - 1200°C and keep it warm for 2 - 6 min;

[0018] Second stage: Stop heating after the first stage ends, and let the furnace temperature drop to 450°C - 700°C within 70 min - 110 min;

[0019] Third stage: Start auxiliary heating and keep it warm after the furnace temperature reaches 450°C - 700°C, with a heat preservation time of 60 - 120 min, and then stop heating and cool down.

[0020] Furthermore, for the production process of the low-sulfur petroleum coke as described above, for the activation treatment in step (1), the temperature is 80°C - 90°C, the pressure is 40 - 50 MPa, and the time is 3 - 5 h.

[0021] Furthermore, for the production process of the low-sulfur petroleum coke as described above, for the drying in step (1), the temperature is 100°C - 110°C, and the time is 6 - 9 h.

[0022] Furthermore, for the production process of the low-sulfur petroleum coke as described above, the metal compound in step (2) is a composition of at least one of nickel oxide and chromium carbonate and calcium oxide.

[0023] Furthermore, in the production process of low-sulfur petroleum coke as described above, the oxidant in step (2) further contains a certain proportion of hydrogen peroxide.

[0024] Furthermore, in the production process of low-sulfur petroleum coke as described above, for the oxidation treatment in step (2), the temperature is 90°C - 120°C and the time is 6 - 7h.

[0025] Furthermore, in the production process of low-sulfur petroleum coke as described above, for the calcination in step (3), the first stage: raise the temperature of the calcination furnace to 950°C - 1050°C and keep it warm for 2 - 6min.

[0026] Furthermore, in the production process of low-sulfur petroleum coke as described above, for the calcination in step (3), the second stage: stop heating after the first stage ends, and let the furnace temperature drop to 600°C - 700°C within 70min - 110min.

[0027] Furthermore, in the production process of low-sulfur petroleum coke as described above, for the calcination in step (3), the third stage: keep it warm for 60 - 90min.

[0028] Beneficial effects

[0029] The production process of low-sulfur petroleum coke provided by the present invention adopts a treatment method combining activation treatment and gradient calcination, achieving the purpose of desulfurizing high-sulfur petroleum coke, meeting the requirements of energy conservation and environmental protection, and reducing costs.

[0030] Before desulfurizing high-sulfur petroleum coke, the present invention first conducts activation treatment to increase the specific surface area, which is beneficial for the full contact between organic sulfur and the oxidant during the oxidation treatment, accelerating the oxidation rate, and thus enhancing the subsequent desulfurization effect. In particular, a continuous reaction high-pressure mixing treatment device is designed to improve the original separate activation and catalytic oxidation processes to be continuously carried out in the same high-pressure mixing treatment device. One is to simplify the process and reduce the equipment requirements, and the other is to make full use of the heat source, thereby reducing production costs.

[0031] During the calcination desulfurization process of the present invention, gradient calcination is adopted to combine low-temperature calcination with high-temperature short-time calcination, avoiding the high requirements for equipment caused by long-time high-temperature calcination of high-sulfur petroleum coke, reducing the replacement frequency of the refractory materials of the calcination furnace. At the same time, according to the removal characteristics of sulfur-containing substances in different stages of petroleum coke, sulfur-containing substances in different existing forms in petroleum coke are removed in stages, improving the desulfurization efficiency and desulfurization effect, and ensuring that the desulfurization rate of high-sulfur petroleum coke can stably reach a relatively high level of 88% or above 89%. Description of the drawings

[0032] Figure 1This is the process schematic diagram of the present invention.

[0033] Figure 2 This is a simplified diagram of a production system provided by an embodiment of the present invention.

[0034] Explanation of reference numerals in the drawings:

[0035] High-pressure mixing treatment equipment - 1, calcination furnace - 2, (liquid) filter outlet - 3, lye feeding port - 4, high-sulfur petroleum coke feeding port - 5, catalyst feeding port - 6, oxidant feeding port - 7, (solid) discharge port - 8. Specific implementation mode

[0036] The following embodiments are intended to illustrate the present invention rather than further limit the present invention.

[0037] The present invention provides a production process for low-sulfur petroleum coke, including the following steps (for the process principle, refer to Figure 1 ):

[0038] (1) Add lye and high-sulfur petroleum coke to the high-pressure mixing treatment equipment, mix evenly, after activation treatment, filter out moisture and dry at 90°C - 120°C to obtain activated material;

[0039] (2) Add a catalyst and an oxidant to the high-pressure mixing treatment equipment, mix evenly with the activated material, and perform oxidation treatment at 80°C - 130°C to obtain a slurry;

[0040] (3) Filter the slurry, dry it, and then perform calcination to obtain low-sulfur petroleum coke;

[0041] For the said calcination, a combination of low-temperature calcination and high-temperature short-time calcination is adopted. For the low-temperature calcination, the temperature is 450°C - 700°C, and the heat preservation time is 60 - 120 min; for the high-temperature short-time calcination, the temperature is 950°C - 1200°C, and the heat preservation time is 2 - 6 min.

[0042] The production process for low-sulfur petroleum coke provided by the present invention adopts a combination of low-temperature calcination and high-temperature short-time calcination after activation treatment, achieving the purpose of highly efficient and high-quality desulfurization of high-sulfur petroleum coke, meeting environmental protection requirements, and reducing costs.

[0043] Specifically,

[0044] (1) Add Ca(OH)2 solution and high-sulfur petroleum coke to the high-pressure mixing treatment equipment, mix evenly, and perform activation treatment at a temperature of 60°C - 100°C and a pressure of 30 - 60 MPa for 2 - 6 h, and then dry at 90°C - 120°C to obtain activated material.

[0045] Before desulfurizing high-sulfur petroleum coke, the present invention first conducts an activation treatment to increase the specific surface area, which is beneficial for the organic sulfur and the oxidant to fully contact during the oxidation treatment, speeds up the oxidation rate, converts the organic sulfur into the form of sulfoxide or sulfone, and further improves the subsequent desulfurization effect.

[0046] (2) Add a catalyst composed of metal compounds and an oxidant mainly composed of nitric acid to the high-pressure mixing treatment equipment, mix evenly with the activated material, and conduct an oxidation treatment at 80°C - 130°C for 5 - 9 h to obtain a slurry.

[0047] In the present invention, the raw materials used in the processes of obtaining the activated material and the slurry are both placed in the same high-pressure mixing treatment equipment. Firstly, it reduces the demand for the types of equipment. Secondly, it realizes the full utilization of heat sources. For example, the residual temperature of the high-pressure mixing treatment equipment after drying in step (1) is directly used for the oxidation treatment in step (2), thereby reducing the production cost.

[0048] (3) Filter the slurry, and after drying, conduct calcination in three stages:

[0049] The first stage: Raise the temperature of the calcination furnace to 950°C - 1200°C and keep it warm for 2 - 6 min.

[0050] The second stage: Stop heating after the first stage ends, and let the furnace temperature drop to 450°C - 700°C in 70 min - 110 min.

[0051] The third stage: Start auxiliary heating and keep it warm after the furnace temperature reaches 450°C - 700°C. The holding time is 60 - 120 min, and then stop heating and cool down.

[0052] In the calcination desulfurization process of the present invention, gradient calcination is adopted to combine low-temperature calcination with high-temperature short-time calcination, avoiding the high requirements for equipment caused by long-time high-temperature calcination of high-sulfur petroleum coke. At the same time, the sulfur-containing substances in different existing forms in the petroleum coke are removed in stages, which not only improves the desulfurization efficiency and desulfurization effect but also does not damage the equipment.

[0053] Considering that sulfur in petroleum coke exists in various forms, including: thiophene-based sulfur-containing groups embedded in the aromatic carbon skeleton, and adsorbed on the surface or pores of the petroleum coke.

[0054] To further improve the activation effect and increase the specific surface area, the activation treatment in step (1) preferably has a temperature of 80°C - 90°C, a pressure of 40 - 50 MPa, and a time of 3 - 5 h. Thus, during the oxidation process, the oxidant can fully contact the organic sulfur in the petroleum coke, convert the organic sulfur into the form of sulfoxide or sulfone, and further improve the subsequent desulfurization effect.

[0055] Further, to reduce the cost during the processing, the process conditions in the operation steps are controlled. For the drying in step (1), the preferred temperature is 100°C - 110°C, and the time is 6 - 9h.

[0056] In addition, the oxidant in step (2) also contains hydrogen peroxide. During the oxidation treatment, the preferred temperature is 90°C - 120°C, and the time is 6 - 7h. Among them, the holding time at 90 - 105°C is not less than 4h, and the holding time after heating up to above 105°C is not less than 1h. The activation effect of the petroleum coke raw material by the hydrogen peroxide-containing composite oxidant with the same concentration can be improved (the activation specific surface area can be increased by 7 - 13%), thereby improving the desulfurization effect during subsequent calcination.

[0057] Since the raw materials used in the process of obtaining the activated material in step (1) and the slurry in step (2) in the present invention are all placed in the same high-pressure mixing and processing equipment, first, the requirement for the types of equipment is reduced. For example, in addition to completing the activation reaction and drying in step (1) in the high-pressure mixing and processing equipment, the oxidation reaction can also be realized in the high-pressure mixing and processing equipment; second, the heat source is fully utilized, and the remaining temperature of the high-pressure mixing and processing equipment after drying in step (1) is directly used for the oxidation treatment in step (2), thereby reducing the production cost.

[0058] Since sulfur exists in petroleum coke in various forms, to ensure that various forms of sulfur can be effectively removed, preferably, the calcination in step (3) is divided into three stages:

[0059] The first stage: Raise the temperature of the calcination furnace to 950°C - 1050°C and hold for 2 - 6min.

[0060] The second stage: Stop heating after the first stage ends, and let the furnace temperature drop to 600°C - 700°C in 70min - 110min.

[0061] The third stage: Start auxiliary heating and holding after the furnace temperature reaches 600°C - 700°C, with a holding time of 60 - 90min, and then stop heating and cool down.

[0062] Example 1

[0063] (1) Add a 2% mass fraction of Ca(OH)2 solution and high-sulfur petroleum coke (the measured sulfur content is 6.93%) to the high-pressure mixing and processing equipment at a liquid-solid ratio of 5:1, mix evenly, carry out activation treatment at a temperature of 90°C and a pressure of 40MPa for 3.5h, and then dry at 110°C for 7h to obtain the activated material.

[0064] (2) Add the K1 catalyst and an oxidant composed of 9 mol / L nitric acid and 3 mol / L hydrogen peroxide solution to the high-pressure mixing treatment equipment, mix evenly with the activated material, first keep warm at 90 °C for 4 h, then raise the temperature to 110 °C and keep warm for 1.5 h for oxidation treatment to obtain a slurry. Among them, the liquid-solid ratio of the oxidant to the activated material is 10:1, and the mass ratio of the K1 catalyst to the activated material is 1:500.

[0065] (3) Filter the slurry, and after drying, carry out calcination in three stages.

[0066] The first stage: Raise the temperature of the calcination furnace to 1050 °C and keep warm for 2 min.

[0067] The second stage: Stop heating after the first stage ends, and let the furnace temperature drop to 600 °C in about 100 min.

[0068] The third stage: Start auxiliary heating and keep warm after the furnace temperature reaches 600 °C, keep warm for 100 min, then stop heating and cool down.

[0069] The above K1 catalyst is prepared with calcium oxide: nickel oxide: chromium carbonate = 3:1:0.3 with reference to the prior art, and other ratios can also be used in actual applications.

[0070] Example 2

[0071] (1) Add a 2% mass fraction Ca(OH)2 solution and high-sulfur petroleum coke (measured sulfur content 6.93%) to the high-pressure mixing treatment equipment at a liquid-solid ratio of 5:1, mix evenly, carry out activation treatment at a temperature of 80 °C and a pressure of 60 MPa for 5 h, and then dry at 100 °C for 8 h to obtain an activated material.

[0072] (2) Add the K1 catalyst and an oxidant composed of 9 mol / L nitric acid and 3 mol / L hydrogen peroxide solution to the high-pressure mixing treatment equipment, mix evenly with the activated material, first keep warm at 90 °C for 5 h, then raise the temperature to 120 °C and keep warm for 1.5 h for oxidation treatment to obtain a slurry. Among them, the liquid-solid ratio of the oxidant to the activated material is 10:1, and the mass ratio of the K1 catalyst to the activated material is 1:500.

[0073] (3) Filter the slurry, and after drying, carry out calcination in three stages.

[0074] The first stage: Raise the temperature of the calcination furnace to 1000 °C and keep warm for 4 min.

[0075] The second stage: Stop heating after the first stage ends, and let the furnace temperature drop to 650 °C in about 90 min.

[0076] The third stage: After the furnace temperature reaches 650 °C, auxiliary heating and heat preservation are started, heat preservation is carried out for 90 min, and then heating is stopped and cooled down.

[0077] Example 3

[0078] (1) A Ca(OH)2 solution with a mass fraction of 2% and high-sulfur petroleum coke (measured sulfur content of 6.93%) are added to a high-pressure mixing and processing device at a liquid-solid ratio of 5:1, mixed evenly, activated at a temperature of 80 °C and a pressure of 50 MPa for 4 h, and then dried at 120 °C for 6 h to obtain an activated material.

[0079] (2) K1 catalyst and an oxidant composed of 9 mol / L nitric acid and 3 mol / L hydrogen peroxide solution are added to the high-pressure mixing and processing device, mixed evenly with the activated material, first heat-preserved at 100 °C for 4 h, then heated to 110 °C and heat-preserved for 1 h for oxidation treatment to obtain a slurry. Among them, the liquid-solid ratio of the oxidant to the activated material is 10:1, and the mass ratio of the K1 catalyst to the activated material is 1:500.

[0080] (3) The slurry is filtered, dried, and then calcined in three stages.

[0081] The first stage: Raise the temperature of the calcination furnace to 980 °C and carry out heat preservation for 6 min.

[0082] The second stage: After the first stage ends, stop heating and let the furnace temperature drop to 600 °C in about 100 min.

[0083] The third stage: After the furnace temperature reaches 600 °C, start auxiliary heating and heat preservation, carry out heat preservation for 90 min, and then stop heating and cool down.

[0084] Example 4

[0085] (1) A Ca(OH)2 solution with a mass fraction of 2% and high-sulfur petroleum coke (measured sulfur content of 6.93%) are added to a high-pressure mixing and processing device at a liquid-solid ratio of 5:1, mixed evenly, activated at a temperature of 80 °C and a pressure of 60 MPa for 5 h, and then dried at 100 °C for 8 h to obtain an activated material.

[0086] (2) K1 catalyst and an oxidant composed of 9 mol / L nitric acid and 3 mol / L hydrogen peroxide solution are added to the high-pressure mixing and processing device, mixed evenly with the activated material, heated to 120 °C and heat-preserved for 6.5 h for oxidation treatment to obtain a slurry. Among them, the liquid-solid ratio of the oxidant to the activated material is 10:1, and the mass ratio of the K1 catalyst to the activated material is 1:500.

[0087] (3) The slurry is filtered, dried, and then calcined in three stages.

[0088] The first stage: Raise the temperature of the calciner to 1000 °C and keep it warm for 4 min.

[0089] The second stage: Stop heating after the first stage ends, and let the furnace temperature drop to 650 °C in about 90 min.

[0090] The third stage: Start auxiliary heating and keep it warm after the furnace temperature reaches 650 °C, keep it warm for 90 min, and then stop heating and cool down.

[0091] Comparative Example 1

[0092] Compared with Example 1, in step (3) for calcination, instead of using gradient calcination, only raise the temperature of the calciner to 600 °C and keep it warm for 4 h. The remaining operations are the same as in Example 1, and the same raw materials and dosages as in Example 1 are added.

[0093] Comparative Example 2

[0094] Compared with Example 1, in step (3) for calcination, in the first stage, raise the temperature of the calciner to 1050 °C and keep it warm for 45 min, and let the furnace temperature slowly drop below 100 °C in about 220 min. The remaining operations are the same as in Example 1, and the same raw materials and dosages as in Example 1 are added.

[0095] Determine the sulfur content of the low-sulfur petroleum coke obtained in Examples 1-4 and Comparative Examples 1-2, and calculate the desulfurization rate. The sulfur content is detected using a sulfur analyzer. The test results are shown in the following table.

[0096]

[0097] As can be seen from the above table, due to the use of activated high-sulfur petroleum coke, the desulfurization rates of the high-sulfur petroleum coke in Examples 1-4 and Comparative Examples 1-2 both reached over 82%. This is because the specific surface area of the high-sulfur petroleum coke is significantly increased after activation, which helps to fully contact the organic sulfur with the oxidant during the subsequent oxidation treatment, accelerates the oxidation rate, and thus improves the desulfurization effect. However, the present invention can ensure that the desulfurization rate of the high-sulfur petroleum coke stably reaches a high level of over 88% and over 89%. The reason is that, compared with Comparative Example 1, Examples 1-4 undergo three-stage gradient calcination, combining "low-temperature calcination" with "high-temperature short-time calcination" to remove sulfur-containing substances in different forms in petroleum coke in a targeted and staged manner. The first stage calcination is used to quickly remove sulfur-containing substances adsorbed on the surface or pores of petroleum coke at the beginning of calcination. The second stage calcination stops heating after the end of the first stage, and reduces the furnace temperature to a low temperature within a certain period of time to focus on removing sulfone substances produced by oxidation and reduce the high-temperature burden of the equipment. The third stage calcination is to focus on removing sulfur-containing substances embedded in the aromatic carbon skeleton after the first and second stage calcinations. The schemes of Examples 1-4 not only improve the desulfurization efficiency and desulfurization effect, but also avoid the damage to the equipment caused by long-term high-temperature calcination of high-sulfur petroleum coke. Compared with Comparative Example 2, the low-sulfur petroleum coke obtained by gradient calcination in Examples 1-4 removes sulfur-containing substances in different forms in the petroleum coke in stages, thereby improving the desulfurization rate. Compared with Comparative Example 2, the high-temperature short-time sintering time in Examples 1-4 is only 2-6 minutes. Compared with long-term continuous operation at above 1000°C, the maintenance frequency of the calcining furnace is significantly reduced, and the furnace life can be increased by 40%-90%.

[0098] Example 5

[0099] This embodiment provides an exemplary production system for the process examples provided in Examples 1-3 to meet the needs of industrial production capacity. However, it should be pointed out that as long as the technical objectives of Examples 1-3 can be achieved, the processes provided in Examples 1-3 can also be used in other production systems.

[0100] like Figure 2 As shown, the low-sulfur petroleum coke production system provided in this embodiment includes a high-pressure mixing processing device 1 and a calcining furnace 2 which are sequentially arranged on the production line.

[0101] Among them, the high-pressure mixing processing equipment 1 includes an alkali solution feeding port 4, a high-sulfur petroleum coke feeding port 5, a catalyst feeding port 6, and an oxidant feeding port 7. Multiple feeding ports are set to adjust the feeding ratio according to actual needs. The high-pressure mixing processing equipment 1 not only has the ability to provide high pressure and unload high pressure, but also has mixing and stirring functions, heating and insulation functions, and solid-liquid separation functions. The effect expected to be achieved by this equipment is that the raw materials processed by it can be directly sent to the calcining furnace 2 for calcination treatment.

[0102] Through the above production system, the efficiency of the entire production process can be improved to meet the needs of industrial production capacity.

[0103] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A production process of low-sulfur petroleum coke, characterized in that, It includes the following steps: (1) Add the Ca(OH)2 solution and high-sulfur petroleum coke into the high-pressure mixing and processing equipment (1), mix evenly, carry out activation treatment at a temperature of 80°C - 90°C and a pressure of 40 - 50 MPa for 3 - 5 h, and then dry at 100°C - 110°C for 6 - 9 h to obtain the activated material; (2) Add a catalyst composed of metal compounds and an oxidant mainly composed of nitric acid and containing a certain proportion of hydrogen peroxide into the high-pressure mixing and processing equipment (1), mix evenly with the activated material, and carry out oxidation treatment at 90°C - 120°C for 6 - 7 h to obtain a slurry; Among them, the oxidation treatment is that the heat preservation time at 90 - 100°C is not less than 4 h, and the heat preservation time after the temperature rises above 110°C is not less than 1 h; (3) Filter the slurry, dry it, and then carry out calcination in three stages. The first stage: Raise the temperature of the calcination furnace (2) to 950°C - 1050°C and keep it warm for 2 - 6 min; The second stage: Stop heating after the first stage ends, and let the furnace temperature drop to 600°C - 700°C in 70 min - 110 min; The third stage: Start auxiliary heating and heat preservation after the furnace temperature reaches 600°C - 700°C, with a heat preservation time of 60 - 90 min, and then stop heating and cool to obtain low-sulfur petroleum coke; The high-pressure mixing and processing equipment (1) includes an alkali liquid feeding port (4), a high-sulfur petroleum coke feeding port (5), a catalyst feeding port (6), and an oxidant feeding port (7). The high-pressure mixing and processing equipment (1) has functions of mixing and stirring, heating and heat preservation, and solid-liquid separation. The raw materials processed by it can be directly sent to the calcination furnace (2) for calcination treatment.

2. The production process of low-sulfur petroleum coke according to claim 1, characterized in that, The metal compound in the step (2) is a composition of at least one of nickel oxide and chromium carbonate and calcium oxide.

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