Activated carbon and preparation method thereof

Abstract

The invention provides activated carbon and a preparation method thereof, and the preparation method of the activated carbon comprises the following steps: carrying out carbonization treatment on a carbon material in a carbonization zone in a multi-hearth furnace to obtain a carbonized product; activating the carbonized product in an activating area in the multi-hearth furnace by adopting an activating agent to obtain activated carbon; wherein the carbonization zone is located at the upstream of the activation zone; the temperature of the carbonization zone is not more than 700 DEG C, and the temperature of the activation zone is not less than 800 DEG The atmosphere of the carbonization area is a reducing gas, the atmosphere of the activation area is oxygen-enriched air, and the oxygen content in the oxygen-enriched air is 19-21 vol%. The multi-hearth furnace is adopted for an integrated production process, carbonization products obtained through carbonization treatment can be directly subjected to activation treatment, and therefore heat of the carbonization products can be used in the activation treatment process, the energy utilization rate is increased, meanwhile, use of a cooling roller and carbonization product conveying equipment can be reduced, the production efficiency is improved, and the production cost is reduced. The operation time is saved.

Description

Technical Field

[0001] The present invention relates to the technical field of activated carbon preparation, and in particular to activated carbon and a preparation method thereof. Background Art

[0002] Activated carbon has developed pores, huge specific surface area and good chemical stability, making it widely used in various fields such as chemical industry, steel, pharmaceuticals and environmental protection. According to the shape and size, activated carbon can be divided into granular activated carbon and powdered activated carbon. Granular carbon is further divided into columnar activated carbon, spherical activated carbon and crushed activated carbon. As a broad-spectrum adsorption material, activated carbon plays an important role in the field of environmental protection, especially granular activated carbon can be recycled after adsorption saturation, regenerated and recycled, with low application cost, and plays an irreplaceable role in environmental protection applications such as flue gas desulfurization and denitrification, VOCs waste gas treatment, deep purification of drinking water, and wastewater standard improvement.

[0003] The traditional preparation process of granular activated carbon includes grinding, molding (granulation), carbonization, activation, and screening processes in sequence, among which carbonization and activation are the key processes for producing granular activated carbon. The carbonization process of activated carbon is the dry distillation process of the material under low temperature conditions after molding. In this process, the material is gradually heated under a certain low temperature range and air-isolated / reducing atmosphere conditions, so that the material is slowly heated and the volatiles escape, so that the material can maximize the formation of fixed carbon with a skeleton structure. The carbonization process is mainly to remove volatile substances in coal, reduce non-carbon elements, and obtain carbonized materials, which is convenient for subsequent activation. Among them, the activation of activated carbon is divided into physical activation and chemical activation. The physical activation method is to use water vapor or CO without using chemical agents. 2 As an activator, it reacts with water gas at high temperature (up to 1000℃) to obtain the corresponding pore structure by ablating carbon. In the physical activation process, the activation effect of the gas activator on the carbonized material includes: the reaction removes non-organized carbon such as tar, making the originally blocked pores open and unobstructed; the gas activator diffuses into the initial pores to react and make the pores larger; the gas activator selectively activates the surface of the raw carbon to generate new pores.

[0004] Activated carbon is usually carbonized using a vertical carbonization furnace or a converter, and activated using a converter, a slep activation furnace or a multi-chamber furnace. A multi-chamber furnace is also called a multi-stage furnace or a rake furnace. The activation of activated carbon using a multi-chamber furnace has a high degree of automation and mechanization, low labor load for workers, and a good production environment. Compared with other activation equipment, multi-chamber furnaces have a larger production capacity, and an annual output of 10,000 tons of activated carbon with an iodine value of 1000 mg / g can be achieved.

[0005] After carbonization is completed, the carbonized material is usually cooled and then transferred to the activation section, which wastes a lot of energy. In response to this problem, the concept of carbonization and activation integrated production process has emerged. Although the concept of carbonization and activation integrated production process is well conceived, the actual production operation is not ideal. Some domestic companies have used converters to produce activated carbon, but the temperature disorder in the furnace often occurs, resulting in the inability to produce normally.

[0006] On this basis, researching and developing a method for preparing activated carbon is of great significance for effectively utilizing the heat generated by carbonization and reducing equipment operating costs. Summary of the invention

[0007] The main purpose of the present invention is to provide an activated carbon and a preparation method thereof, so as to solve the problems in the prior art that it is difficult to realize an integrated carbonization and activation production process, the heat utilization rate generated by carbonization is low, the equipment operating cost is high, and the activated carbon quality is poor.

[0008] In order to achieve the above-mentioned purpose, the present invention provides a method for preparing activated carbon on the one hand, which comprises: carbonizing a carbon material in a carbonization zone in a multi-chamber furnace to obtain a carbonized product; activating the carbonized product with an activator in an activation zone in the multi-chamber furnace to obtain activated carbon; wherein the carbonization zone is located upstream of the activation zone; the temperature of the carbonization zone is ≤700°C, and the temperature of the activation zone is ≥800°C; the atmosphere of the carbonization zone is a reducing gas, and the atmosphere of the activation zone is oxygen-enriched air, and the oxygen content in the oxygen-enriched air is 19-21 vol%.

[0009] Furthermore, along the material flow direction, the carbonization zone includes at least one carbonization partition layer, preferably 1 to 7 carbonization partition layers.

[0010] Furthermore, along the material flow direction, the carbonization zone includes 7 layers of carbonization partitions in sequence, and the temperature of each layer of carbonization partition increases layer by layer.

[0011] Furthermore, the terminal temperature of the carbonization treatment is 500-650°C.

[0012] Furthermore, the feed rate of the carbon material into the carbonization zone is 0.5 to 3 t / h, and the residence time is 2 to 4 hours.

[0013] Furthermore, the feed rate of the activator into the activation zone is 4.5-5.5 kg / h.

[0014] Furthermore, the ratio of the feed rate of the activator into the activation zone to the feed rate of the carbonization product into the activation zone is (1.5-5):1.

[0015] Furthermore, the activating agent is water vapor.

[0016] Furthermore, along the material flow direction, the activation zone includes at least one activation partition layer, preferably 1 to 10 activation partition layers.

[0017] Furthermore, in the multi-chamber furnace, the total number of layers of the carbonization partitions and the activation partitions is 9 to 17 layers.

[0018] Furthermore, the terminal temperature of the activation treatment is 800-1000° C., preferably 850-1000° C., and the residence time of the carbonized product in the activation zone is 3-6 hours.

[0019] Furthermore, the reducing gas is nitrogen.

[0020] Furthermore, during the activation treatment, oxygen-enriched air is introduced into the activation zone, preferably at a rate of 2500 to 3300 m / s. 3 / h.

[0021] Furthermore, a central axis is provided at the center of the multi-chamber furnace, a rake arm is connected in the vertical direction of the central axis, and rake teeth are provided on the rake arm. The central axis drives the rake teeth on the rake arm to turn over, so that the material flows from the upstream area to the downstream area, so that the carbon material is carbonized and activated in turn until the activated carbon is discharged from the outlet of the multi-chamber furnace.

[0022] Further, the number of rake teeth is the same as the total number of layers of the carbonization partition and the activation partition.

[0023] Furthermore, the rotation speed of the center shaft in the multi-chamber furnace is 0.3-0.4 r / min.

[0024] Furthermore, the multi-chamber furnace is equipped with a burner, and the preparation method further comprises: sending the gas generated in the multi-chamber furnace into the burner through an induced draft fan.

[0025] Furthermore, the pressure in the multi-chamber furnace is -20 to -50 Pa, and the flow rate of the induced draft fan is 25,000 to 35,000 m 3 / h.

[0026] Furthermore, during the carbonization treatment and the activation treatment, the burner opening is set to ≤20%.

[0027] 8. According to the method for preparing activated carbon of claim 1, the carbon material is selected from one or more of raw coal, wood carbon material, fruit shell, plastic resin and asphalt; and / or the carbon material is selected from waste activated carbon.

[0028] Furthermore, the carbon material is in the form of crushed particles, columnar particles or spherical particles.

[0029] Furthermore, the average particle size of the carbon material is 3 to 8 mm.

[0030] In order to achieve the above-mentioned purpose, another aspect of the present invention further provides an activated carbon, which is prepared by the above-mentioned activated carbon preparation method provided in the present application.

[0031] Furthermore, the specific surface area of ​​activated carbon is 700-1070 cm 2 / mg, porosity is 5~75%.

[0032] According to the technical solution of the present invention, the traditional carbonization and activation process is a "split" process in which carbonization is first performed in a converter, and the resulting carbonized material is placed in a converter for high-temperature activation after cooling, wherein carbonization is a pyrolysis endothermic reaction, and activation is also an endothermic reaction involving an activator (such as water vapor), but the endothermic heat of the carbonization and activation processes is different. Due to the endothermic reactions with different endothermic heats, and the participation of an activator (such as water vapor) in the activation process, the production process is difficult to control, and the quality of the activated carbon is greatly affected by the temperature changes in the furnace, which may even cause production accidents.

[0033] The present application adopts a multi-chamber furnace for an "integrated" production process, which can directly activate the carbonized product obtained by carbonization treatment, so that the heat of the carbonized product can be used in the activation process, improving energy utilization, while also reducing the use of cooling drums and carbonized product conveying equipment, improving production efficiency, and saving operation time. The above-mentioned activated carbon preparation method provided by the present application can shorten the production time as much as possible while improving the quality of activated carbon, so that the processing time is significantly shortened compared to the traditional processing process. DETAILED DESCRIPTION

[0034] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below in conjunction with the embodiments.

[0035] As described in the background technology, the existing activated carbon preparation process has the problem that it is difficult to realize the integrated production process of carbonization and activation, the heat utilization rate generated by carbonization is low, the equipment operation cost is high, and the quality of activated carbon is poor. In order to solve the above technical problems, the present application provides a method for preparing activated carbon, which comprises: carbonizing a carbon material in a carbonization zone in a multi-chamber furnace to obtain a carbonized product; activating the carbonized product with an activator in an activation zone in the multi-chamber furnace to obtain activated carbon; wherein the carbonization zone is located upstream of the activation zone; the temperature of the carbonization zone is ≤700°C, and the temperature of the activation zone is ≥800°C; the atmosphere of the carbonization zone is a reducing gas, and the atmosphere of the activation zone is oxygen-enriched air, and the oxygen content in the oxygen-enriched air is 19-21 vol%.

[0036] Traditional carbonization and activation is a "split" process in which carbonization is first performed in a converter, and the resulting carbonized material is placed in a converter for high-temperature activation after cooling. Carbonization is a pyrolysis endothermic reaction, and activation is also an endothermic reaction involving an activator (such as water vapor). However, the endothermic heat of the carbonization and activation processes is different. Due to the endothermic reactions with different endothermic heats, and the participation of an activator (such as water vapor) in the activation process, the production process is difficult to control, and the quality of the activated carbon is greatly affected by the temperature changes in the furnace, which may even cause production accidents.

[0037] The present application adopts a multi-chamber furnace for an "integrated" production process, which can directly activate the carbonized product obtained by carbonization treatment, so that the heat of the carbonized product can be used in the activation process, improving energy utilization, while also reducing the use of cooling drums and carbonized product conveying equipment, improving production efficiency, and saving operation time. The above-mentioned activated carbon preparation method provided by the present application can shorten the production time as much as possible while improving the quality of activated carbon, so that the processing time is significantly shortened compared to the traditional processing process.

[0038] In a preferred embodiment, along the material flow direction, the carbonization zone includes at least one carbonization partition layer, preferably 1 to 7 carbonization partition layers. Compared with a single-layer carbonization zone, dividing the carbonization zone into 1 to 7 carbonization partition layers is conducive to making the carbon material heated more uniformly, facilitating step-by-step temperature increase for carbonization treatment, thereby improving the effect of carbonization treatment.

[0039] In a preferred embodiment, the carbonization zone includes 7 layers of carbonization partitions in sequence along the material flow direction, and the temperature of each layer of carbonization partition increases layer by layer. Compared with a single-layer carbonization zone, dividing the carbonization zone into 7 layers of carbonization partitions is conducive to making the carbon material heated more uniformly, facilitating step-by-step temperature increase for carbonization treatment, thereby improving the effect of carbonization treatment.

[0040] In a preferred embodiment, a central axis is provided in the center of the multi-chamber furnace, a rake arm is connected in the vertical direction of the central axis, and rake teeth are provided on the rake arm, and the central axis drives the rake teeth on the rake arm to flip, so that the material flows from the upstream area to the downstream area, so that the carbon material is sequentially carbonized and activated, until the activated carbon is discharged from the outlet of the multi-chamber furnace; preferably, the number of rake teeth is the same as the total number of layers of the carbonization partition and the activation partition. The above method is convenient for gradually transporting the carbon raw material to each layer in the furnace, and is also conducive to making the heat distribution more uniform, and is conducive to making the obtained carbonization product more fully contact with the activator, thereby improving the activation treatment effect.

[0041] In order to improve the effects of carbonization and activation treatments and to shorten production time, preferably, the rotation speed of the center shaft in the multi-hearth furnace is 0.3-0.4 r / min.

[0042] In order to improve the effect of the carbonization treatment, preferably, the end temperature of the carbonization treatment is 500-650°C.

[0043] In a preferred embodiment, the feed rate of the carbon material into the carbonization zone is 0.5-3 t / h, and the residence time is 2-4 hours. The feed rate of the carbon material into the carbonization zone and the residence time in the carbonization zone include but are not limited to the above ranges, and limiting them within the above ranges is conducive to improving the effect of the carbonization treatment, while shortening the production time and improving the production efficiency.

[0044] In a preferred embodiment, the feed rate of the activator into the activation zone is 4.5-5.5 kg / h. The feed rate of the activator into the activation zone includes but is not limited to the above range, and limiting it within the above range is conducive to improving the utilization rate of the activator, improving the effect of the activation treatment, and thus helping to increase the yield of activated carbon.

[0045] In order to further improve the reaction efficiency of the activator and the carbonized product and further improve the activation treatment effect, preferably, the ratio of the feed rate of the activator into the activation zone to the feed rate of the carbonized product into the activation zone is (1.5-5):1.

[0046] The activator in the present application can be any commonly used type in the art, without particular limitation, as long as it can play an activating role. In a preferred embodiment, the activator includes but is not limited to water vapor.

[0047] In a preferred embodiment, along the material flow direction, the activation zone includes at least one activation partition layer, preferably 1 to 10 activation partition layers. Compared with a single-layer carbonization zone, dividing the carbonization zone into 1 to 10 activation partition layers is conducive to more uniform heating of the carbonization product, facilitating step-by-step temperature increase for activation treatment, thereby improving the effect of the activation treatment and improving the quality of the activated carbon.

[0048] In order to make the carbon material heat more evenly and facilitate the carbonization treatment by gradually increasing the temperature, thereby further improving the effect of the carbonization treatment; at the same time, in order to make the carbonization product heat more evenly and facilitate the activation treatment by gradually increasing the temperature, thereby further improving the effect of the activation treatment, preferably, in the multi-chamber furnace, the total number of layers of carbonization partitions and activation partitions is 9 to 17 layers.

[0049] In a preferred embodiment, the end temperature of the activation treatment is 800-1000°C, and the residence time of the carbonized product in the activation zone is 3-6 hours. The end temperature of the activation treatment and the residence time of the carbonized product in the activation zone include but are not limited to the above ranges. Limiting them to the above ranges is conducive to improving the activation treatment effect, shortening the treatment time, and reducing energy consumption.

[0050] In order to further improve the activation treatment effect and further enhance the quality of activated carbon, preferably, the end point temperature of the activation treatment is 850-1000°C.

[0051] In a preferred embodiment, the reducing gas is nitrogen.Carrying out the carbonization treatment in the above-mentioned type of reducing gas is beneficial to improving the yield of the carbonized product.

[0052] In a preferred embodiment, the oxygen-enriched air is introduced at a rate of 2500 to 3300 m / s. 3 The introduction rate of oxygen-enriched air includes but is not limited to the above range. Limiting it within the above range is beneficial to improving the effect of activation treatment, thereby helping to increase the yield of activated carbon.

[0053] In a preferred embodiment, the multi-chamber furnace is equipped with a burner, and the preparation method further comprises: sending the gas generated in the multi-chamber furnace into the burner through an induced draft fan. Since the material and the flue gas move in opposite directions during the operation of the multi-chamber furnace, using an induced draft fan to send the gas in the furnace into the burner for processing is conducive to regulating the furnace temperature and the material heating rate.

[0054] In order to better control the furnace temperature and material heating rate, preferably, the pressure in the multi-chamber furnace is -20 to -50 Pa, and the induced draft fan flow rate is 25000 to 35000 m 3 / h.

[0055] In order to better control the furnace temperature and the material heating rate, preferably, during the carbonization treatment and activation treatment, the burner opening is set to ≤20%.

[0056] In a preferred embodiment, the carbon material includes but is not limited to one or more of raw coal, wood-based carbon material, fruit shell, plastic resin and asphalt; and / or, the carbon material includes but is not limited to waste activated carbon.

[0057] The present application does not specifically limit the shape of the carbon material. In a preferred embodiment, the carbon material is broken particles, columnar particles or spherical particles.

[0058] In order to improve the effects of carbonization and activation treatment, preferably, the average particle size of the carbon material is 3 to 8 mm.

[0059] On the other hand, the present application also provides an activated carbon, which is prepared by the above-mentioned activated carbon preparation method provided by the present application. The above-mentioned preparation method provided by the present application can improve energy utilization while improving the quality of activated carbon, reduce the use of cooling drums and carbonization product conveying equipment, improve production efficiency, and save operation time. The activated carbon prepared by the above-mentioned preparation method has a high specific surface area and porosity, and is of good quality.

[0060] In a preferred embodiment, the specific surface area of ​​the activated carbon is 700 to 1070 cm 2 / mg, and the porosity is 5-75%. The specific surface area and porosity of activated carbon include but are not limited to the above ranges. Limiting them within the above ranges is conducive to improving the adsorption performance of activated carbon and facilitating its application in flue gas desulfurization and denitrification, VOCs waste gas treatment, deep purification of drinking water, and wastewater quality improvement.

[0061] The present application is further described in detail below in conjunction with specific embodiments. These embodiments should not be construed as limiting the scope of protection claimed in the present application.

[0062] It should be noted that the multi-chamber furnace used in the present application is a Φ8.0×16C type (outer diameter is 8m, with a total of 17 layers, of which the carbonization zone includes 7 layers of carbonization partitions, and the activation zone includes 9 layers of activation partitions) multi-chamber furnace produced by HK Company, in which a carbonization zone and an activation zone are provided, and the carbonization zone is located upstream of the activation zone, and along the material flow direction, it includes 7 layers of carbonization partitions and 10 layers of activation partitions in sequence.

[0063] Example 1

[0064] The above multi-chamber furnace is used to prepare activated carbon. A method for preparing activated carbon comprises:

[0065] The raw coal with an average particle size of 3 to 8 mm is fed into the carbonization zone of the multi-hearth furnace at a feed rate of 2.1 t / h for carbonization treatment. The end temperature of the carbonization treatment is 600°C. The residence time of the raw coal in the carbonization zone is 3 hours. The obtained carbonization product is passed into the activation zone.

[0066] The carbonization product was fed at a rate of 1.0 kg / h, the steam was fed at a rate of 5.0 kg / h, and the oxygen-enriched air was fed at a rate of 3000 m 3 / h is introduced into the activation zone for activation treatment, wherein the end temperature of the activation treatment is 900°C, the residence time of the carbonized product in the activation zone is 4h, and activated carbon is collected;

[0067] During the above process, the pressure in the multi-chamber furnace is -50Pa, and the flow rate of the induced draft fan is 35000m 3 / h, and during the carbonization and activation treatments, the burner opening was set to 20%.

[0068] Example 2

[0069] The difference from Example 1 is that the terminal temperature of the carbonization treatment is 700°C.

[0070] Example 3

[0071] The difference from Example 1 is that the terminal temperature of the carbonization treatment is 500°C.

[0072] Example 4

[0073] The difference from Example 1 is that the terminal temperature of the carbonization treatment is 650°C.

[0074] Example 5

[0075] The difference from Example 1 is that the terminal temperature of the carbonization treatment is 450°C.

[0076] Example 6

[0077] The difference from Example 1 is that the feed rate of raw coal into the carbonization zone is 0.5 t / h, and the residence time is 4 h.

[0078] Example 7

[0079] The difference from Example 1 is that the feed rate of raw coal into the carbonization zone is 3 t / h, and the residence time is 2 h.

[0080] Example 8

[0081] The difference from Example 1 is that the feed rate of raw coal into the carbonization zone is 4 t / h, and the residence time is 1 h.

[0082] Example 9

[0083] The difference from Example 1 is that the feed rate of water vapor into the activation zone is 4.5 kg / h.

[0084] Example 10

[0085] The difference from Example 1 is that the feed rate of water vapor into the activation zone is 5.5 kg / h.

[0086] Embodiment 11

[0087] The difference from Example 1 is that the feed rate of water vapor into the activation zone is 3.5 kg / h.

[0088] Example 12

[0089] The difference from Example 1 is that the terminal temperature of the activation treatment is 800° C., and the residence time of the carbonized product in the activation zone is 6 hours.

[0090] Example 13

[0091] The difference from Example 1 is that the terminal temperature of the activation treatment is 1000° C., and the residence time of the carbonized product in the activation zone is 3 hours.

[0092] Embodiment 14

[0093] The difference from Example 1 is that the terminal temperature of the activation treatment is 700° C., and the residence time of the carbonized product in the activation zone is 7 hours.

[0094] Comparative Example 1

[0095] The activated carbon is prepared by a "split" process, which includes:

[0096] 8 tons of raw coal with an average particle size of 6 mm were introduced into a converter (Xi'an Sanrui, Φ2500×26000mm), the pressure in the converter was set to -200Pa, and carbonization treatment was carried out in an oxygen-free atmosphere. A carbonized product was obtained after 2.5 hours, and the carbonized product was cooled to room temperature. The cooled carbonized product was introduced into a Slep furnace for activation treatment with water vapor, and the activation treatment was carried out in oxygen-enriched air with an oxygen content of 19vol%, and the activated product, i.e., activated carbon, was obtained after 12 hours.

[0097] The specific surface area and porosity of the activated carbon were tested by nitrogen adsorption and desorption method, and the test results are shown in Table 1. Table 1 also summarizes the total time spent on carbonization and activation of all the above examples and comparative examples.

[0098] Table 1

[0099] Total carbonization and activation time (h) <![CDATA[Specific surface area (cm 2 / mg)]]> Porosity (%) Example 1 7 1020 75 Example 2 7 1000 75 Example 3 7 970 75 Example 4 7 960 75 Example 5 7 950 70 Example 6 8 1030 75 Example 7 6 1000 68 Example 8 9 700 65 Example 9 7 1000 73 Example 10 7 1050 75 Embodiment 11 7 950 70 Example 12 9 930 65 Example 13 6 1070 70 Embodiment 14 10 850 65 Comparative Example 1 14.5 950 70

[0100] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0101] Traditional carbonization and activation is a "split" process in which carbonization is first performed in a converter, and the resulting carbonized material is placed in a converter for high-temperature activation after cooling. Carbonization is a pyrolysis endothermic reaction, and activation is also an endothermic reaction involving an activator (such as water vapor). However, the endothermic heat of the carbonization and activation processes is different. Due to the endothermic reactions with different endothermic heats, and the participation of an activator (such as water vapor) in the activation process, the production process is difficult to control, and the quality of the activated carbon is greatly affected by the temperature changes in the furnace, which may even cause production accidents.

[0102] The present application adopts a multi-chamber furnace for an "integrated" production process, which can directly activate the carbonized product obtained by carbonization treatment, so that the heat of the carbonized product can be used in the activation process, improving energy utilization, while also reducing the use of cooling drums and carbonized product conveying equipment, improving production efficiency, and saving operation time. The above-mentioned activated carbon preparation method provided by the present application can shorten the production time as much as possible while improving the quality of activated carbon, so that the processing time is significantly shortened compared to the traditional processing process.

[0103] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those described herein, for example.

[0104] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for preparing activated carbon, characterized in that: The preparation method of the activated carbon comprises: Carrying out carbonization treatment on the carbon material in the carbonization zone of the multi-hearth furnace to obtain a carbonized product; In the activation zone of the multi-chamber furnace, an activating agent is used to activate the carbonization product to obtain the activated carbon; Wherein, the carbonization zone is located upstream of the activation zone; the temperature of the carbonization zone is ≤700°C, and the temperature of the activation zone is ≥800°C; the atmosphere of the carbonization zone is reducing gas, and the atmosphere of the activation zone is oxygen-enriched air, and the oxygen content in the oxygen-enriched air is 19-21 vol%.

2. The method for preparing activated carbon according to claim 1, characterized in that: Along the material flow direction, the carbonization zone includes at least one carbonization partition layer, preferably 1 to 7 carbonization partition layers; Preferably, along the material flow direction, the carbonization zone includes 7 layers of carbonization partitions in sequence, and the temperature of each layer of the carbonization partition increases layer by layer; Preferably, the terminal temperature of the carbonization treatment is 500-650°C.

3. The method for preparing activated carbon according to claim 1 or 2, characterized in that: The feeding rate of the carbon material into the carbonization zone is 0.5-3 t / h, and the residence time is 2-4 h.

4. The method for preparing activated carbon according to any one of claims 1 to 3, characterized in that: The feed rate of the activator into the activation zone is 4.5 to 5.5 kg / h; Preferably, the ratio of the feed rate of the activating agent into the activation zone to the feed rate of the carbonization product into the activation zone is (1.5-5):1; Preferably, the activating agent is water vapor.

5. The method for preparing activated carbon according to claim 4, characterized in that: Along the material flow direction, the activation zone includes at least one activation partition layer, preferably 1 to 10 activation partition layers; Preferably, in the multi-chamber furnace, the total number of layers of the carbonization partition and the activation partition is 9 to 17 layers; Preferably, the terminal temperature of the activation treatment is 800-1000° C., preferably 850-1000° C., and the residence time of the carbonized product in the activation zone is 3-6 hours.

6. The method for preparing activated carbon according to claim 5, characterized in that: The reducing gas is nitrogen; Preferably, during the activation treatment, the oxygen-enriched air is introduced into the activation zone, and preferably the introduction rate of the oxygen-enriched air is 2500-3300 m / s. 3 / h.

7. The method for preparing activated carbon according to any one of claims 1 to 6, characterized in that: A central axis is provided in the center of the multi-chamber furnace, a rake arm is connected in the vertical direction of the central axis, and rake teeth are provided on the rake arm, and the central axis drives the rake teeth on the rake arm to flip, so that the material flows from the upstream area to the downstream area, so that the carbon material is subjected to the carbonization treatment and the activation treatment in sequence, until the activated carbon is discharged from the outlet of the multi-chamber furnace; Preferably, the number of the rake teeth is the same as the total number of layers of the carbonization partition and the activation partition; Preferably, the rotation speed of the center shaft in the multi-hearth furnace is 0.3-0.4 r / min; Preferably, the multi-chamber furnace is equipped with a burner, and the preparation method further comprises: sending the gas generated in the multi-chamber furnace into the burner through an induced draft fan; Preferably, the pressure in the multi-chamber furnace is -20 to -50 Pa, and the flow rate of the induced draft fan is 25000 to 35000 m 3 / h; Preferably, during the carbonization treatment and the activation treatment, the burner opening is set to ≤20%.

8. The method for preparing activated carbon according to claim 1, characterized in that: The carbon material is selected from one or more of raw coal, wood-based carbon materials, fruit shells, plastic resins and asphalt; and / or, the carbon material is selected from waste activated carbon.

9. The method for preparing activated carbon according to claim 1, characterized in that: The carbon material is broken particles, columnar particles or spherical particles; Preferably, the average particle size of the carbon material is 3 to 8 mm.

10. An activated carbon, characterized in that The activated carbon is prepared by the method for preparing activated carbon according to any one of claims 1 to 9; Preferably, the specific surface area of ​​the activated carbon is 700 to 1070 cm 2 / mg, porosity is 5~75%.