Activated carbon carbonization method based on belt system

Abstract

The invention discloses an activated carbon carbonization method based on a belt type system, which adopts belt type production equipment as carbonization equipment of activated carbon, and prepares the activated carbon according to the thermal regulation of the belt type production equipment, the ingredients of the activated carbon and the index requirements of standard activated carbon finished products. The distribution thickness and the running speed of the activated carbon card slivers are strictly controlled during distribution, and the distribution thickness of the activated carbon card slivers is accurately controlled to be matched with the thermal regulation of belt type production equipment, so that the carbonization heating uniformity and stability of the activated carbon card slivers are greatly improved, the abrasion of activated carbon is greatly reduced, and the service life of the activated carbon card slivers is prolonged. The method disclosed by the invention is simple in process and easy to operate, and has a wide industrial application prospect and remarkable economic benefits.

Description

Technical Field

[0001] The invention relates to an activated carbon preparation technology, in particular to an activated carbon carbonization method based on a belt system, and belongs to the technical field of activated carbon production. Background Art

[0002] The existing activated carbon production process needs to go through the processes of grinding, kneading, granulation, carbonization, cooling, activation, cooling, packaging, etc. Carbonization and activation are the heat treatment processes of activated carbon production, and they are also the two core processes of activated carbon production. The technical level and production stability of the processes directly determine the quality of the activated carbon products.

[0003] Existing activated carbon generally uses a carbonization rotary kiln and a Slep activation furnace or a carbonization rotary kiln and an activation rotary kiln to carbonize and activate the activated carbon. When using a carbonization rotary kiln to carbonize activated carbon, the carbonization rotary kiln has a low filling rate, the volatile matter burns in the upper part, and the activated carbon moves in the lower part, resulting in a large temperature difference in the vertical section. And because the rotary kiln cannot accurately measure and control the temperature, it can only control the maximum temperature to form the temperature curve in the kiln. The temperature curve cannot be accurately controlled, and the temperature in the furnace is prone to fluctuations. The maximum temperature stability of the carbonization rotary kiln is generally ±50~100℃ / 24h, and the temperature difference of the effective vertical section of the material is generally ≤±10~40℃, that is, the activated carbon is heated unevenly in the rotary kiln, which greatly reduces the compliance rate of the finished product. In addition, the activated carbon in the carbonizing rotary kiln turns with the rotation of the kiln body, that is, the material is in a moving state in the rotary kiln, which can easily cause the activated carbon to break due to stress before it forms a certain strength, resulting in loss of quality of the finished product; further, the maximum output of a single carbonizing rotary kiln is only 8,000 tons / year, and generally multiple carbonizing rotary kilns are required to be used in conjunction with a Slep activation furnace, which seriously restricts the production capacity of finished activated carbon. Summary of the invention

[0004] In view of the problems in the prior art that the existing carbonization rotary kiln has uneven heating, high movement wear rate and the like, resulting in low output of qualified activated carbon finished products, the present invention adopts belt production equipment as activated carbon carbonization equipment, and strictly controls the thickness of the activated carbon raw strips during laying according to the thermal system of the belt production equipment, the activated carbon ingredients and the index requirements of the qualified activated carbon finished products. By precisely controlling the thickness of the activated carbon raw strips (i.e., activated carbon biomass, including but not limited to strips) and combining it with the thermal system of the belt production equipment, the uniformity and stability of the carbonization heating of the activated carbon raw strips are greatly improved, effectively ensuring and promoting the yield of qualified activated carbon finished products, and having the characteristics of large-scale industrial practical application.

[0005] In order to achieve the above technical objectives, the technical solutions adopted by the present invention are as follows:

[0006] An activated carbon carbonization method based on a belt system, the method comprising:

[0007] 1) According to the direction of the material, the belt system is divided into a distribution section, a drying section, a carbonization section and a heat preservation section. After the activated carbon strips are distributed in the distribution section, they are processed in the drying section, the carbonization section and the heat preservation section in turn to obtain the carbonized material.

[0008] 2) Before spreading, the thickness of the activated carbon strips is calculated based on the thermal demand parameters of the carbonized material and the finished product demand index. The activated carbon strips are spread in the spreading section according to the calculated thickness.

[0009] 3) The running speed of the activated carbon strips in the belt system is calculated based on the actual cloth thickness of the activated carbon strips, real-time thermal parameters and the target output of the carbonized material.

[0010] Preferably, the method further comprises:

[0011] 4) The activated carbon carbonized material output from the belt carbonization furnace is cooled, and then protected by a protective gas to obtain a finished activated carbon.

[0012] Preferably, in step 1), the temperature of the drying section is 150-400°C, preferably 180-350°C, more preferably 200-300°C.

[0013] Preferably, in step 1), the temperature of the carbonization section is 350-800°C, preferably 400-750°C, more preferably 450-700°C.

[0014] Preferably, in step 1), the temperature of the insulation section is 500-650°C, preferably 530-620°C, more preferably 550-600°C.

[0015] Preferably, the drying section is constant temperature drying or variable temperature drying. Preferably, the drying section is segmented constant temperature drying or segmented variable temperature drying.

[0016] Preferably, the drying section includes a first drying section and a second drying section, wherein: the inlet temperature of the first drying section is 150-200°C, and the outlet temperature of the first drying section is 200-300°C. The inlet temperature of the second drying section is 250-350°C, and the outlet temperature of the second drying section is 300-400°C.

[0017] Preferably, the carbonization stage is a variable temperature carbonization stage, preferably, the inlet temperature of the carbonization stage is 350-500°C, and the outlet temperature of the carbonization stage is 600-800°C.

[0018] Preferably, the heating rate in the carbonization stage does not exceed 20°C / min, preferably 10-20°C / min. The carbonization time does not exceed 45 min, preferably 15-40 min.

[0019] Preferably, in step 4), the activated carbon carbonized material is cooled by indirect water cooling and nitrogen direct cooling so that the temperature of the activated carbon carbonized material after cooling is not higher than 50°C, preferably not higher than 30°C.

[0020] Preferably, in step 2), the thickness of the activated carbon strip is calculated based on the thermal demand parameters of the carbonized material and the finished product demand index: the thickness of the activated carbon strip is set to h, cm. Then:

[0021]

[0022] In the above formula (1), a is the correction coefficient, which is 8-12. J is the coal tar content, %. t T is the oxygen content in the carbonization stage, %. tmax is the highest temperature in the carbonization stage, °C. t is the heating time of carbonization stage, min. T1 is the inlet temperature of carbonization furnace, °C; t tb is the holding time of the highest temperature in the carbonization stage, min. t D is the wear resistance of carbonized material, and its value is ≥97%. t is the compressive strength of carbonized material, and its value is ≥450N. b is the correction constant, and its value is -2~2.

[0023] Preferably, step 3) is as follows: the loading amount of a single material box is q, kg, then:

[0024] q=ρ×h×A (2)

[0025] Assume that the running speed of the activated carbon strip in the belt system is V, m / min. Then:

[0026] V=Q×A 0.5 / (q×j×k) (3)

[0027] In the above formulas (2)-(3), ρ is the bulk density of the activated carbon strips in the material box, kg / m 3 A is the material storage area of ​​a single material box, m 2 Q is the target output of carbonized material, kg / min. j is the number of columns of the material boxes in the width direction of the belt system. k is the number of layers of the material boxes in the vertical direction.

[0028] As a preferred method, along the moving direction of the material, according to the different heating temperatures required for the material, n temperature zones are divided in the length direction of the belt system, and then:

[0029] V≤v×L n / (T n -T n-1 ) (4)

[0030] In the above formula (4), v is the carbonization heating rate, °C / min; L n is the length of each carbonization temperature zone of the belt system, m; T n is the temperature of each carbonization temperature zone of the belt system, ℃, and n is an integer greater than or equal to 2.

[0031] Preferably, the material box is a circular, rectangular or regular polygonal sagger, and through holes are provided on the side wall and the bottom wall of the sagger. The depth of the sagger is 1.2-4 times the thickness of the cloth, preferably 1.5-3 times.

[0032] Preferably, the opening rate on the side wall of the sagger is not less than 50%, preferably 55-95%, more preferably 60-80%.

[0033] Preferably, the opening rate on the bottom wall of the sagger is not less than 60%, preferably 65-90%, more preferably 70-85%.

[0034] Preferably, the belt system is a belt furnace, and a plurality of temperature detectors are evenly arranged inside the belt furnace according to the direction of the material.

[0035] Preferably, a protective gas supply device connected to the interior of the carbonization section is provided, wherein the protective gas is an inert gas or nitrogen, preferably nitrogen.

[0036] In the prior art, when using a carbonization rotary kiln to carbonize activated carbon, due to the low filling rate of the carbonization rotary kiln, the temperature difference of the material on the vertical section is large, and the rotary kiln cannot accurately measure and control the temperature, the temperature in the furnace fluctuates greatly. The combination of the two factors makes the activated carbon often heated unevenly in the kiln, and there is a phenomenon of incomplete carbonization or excessive carbonization, which leads to an increase in the rate of unqualified product quality; in addition, the activated carbon is always in a state of motion in the rotary kiln, and the activated carbon is easy to produce fragments due to mutual wear and tear before it forms a certain strength, which ultimately causes a loss of product quality. Furthermore, the existing carbonization rotary kiln has limited production capacity, and a single carbonization rotary kiln cannot be well matched with a Slep activation furnace for joint use, which restricts the production efficiency of activated carbon.

[0037] In the present invention, a belt system (for example, a belt furnace with simultaneous heating on the upper and lower sides) is used as the carbonization equipment for activated carbon, and before the activated carbon is laid on the belt furnace, a fitting calculation is performed to obtain the laying thickness of the activated carbon raw strips according to the activated carbon carbonization heat treatment process system, the activated carbon ingredients, and the indicators of the activated carbon carbonization product, so that the activated carbon raw strips can be heated evenly and stably during drying, carbonization, and heat preservation treatment in the belt furnace, which is beneficial to quickly improve the pressure resistance and wear resistance of the activated carbon, and effectively ensure the qualified rate and yield of the finished activated carbon.

[0038] The thickness of activated carbon strips is calculated based on the thermal demand parameters of carbonized materials and the finished product demand index: the thickness of activated carbon strips is set to h, cm. Then:

[0039]

[0040] In the above formula (1), a is the correction coefficient, which is 8-12. J is the coal tar content, %. t T is the oxygen content in the carbonization stage, %. tmax is the highest temperature in the carbonization stage, °C. t is the heating time of carbonization stage, min. T1 is the inlet temperature of carbonization furnace, °C; t tb is the holding time of the highest temperature in the carbonization stage, min. t D is the wear resistance of carbonized material, and its value is ≥97%. t is the compressive strength of carbonized material, and its value is ≥450N. b is the correction constant, and its value is -2~2.

[0041] In the present invention, the operating rate of the activated carbon in the belt furnace is controlled by the actual cloth thickness of the activated carbon raw strips, the real-time thermal parameters and the target output of the carbonized material. By precisely controlling the operating rate of the activated carbon, it is ensured that the activated carbon can reach a relatively ideal state in different stages (drying, carbonization, and insulation), and ultimately the stable control of the quality and output of the finished activated carbon is achieved.

[0042] The control of the running speed of activated carbon in the belt furnace is as follows: the loading amount of a single material box is set to q, kg, then:

[0043] q=ρ×h×A (2)

[0044] Assume that the running speed of the activated carbon strip in the belt system is V, m / min. Then:

[0045] V=Q×A 0.5 / (q×j×k) (3)

[0046] In the above formulas (2)-(3), ρ is the bulk density of the activated carbon strips in the material box, kg / m3 A is the material storage area of ​​a single material box, m 2 Q is the target output of carbonized material, kg / min. j is the number of columns of the material boxes in the width direction of the belt system. k is the number of layers of the material boxes in the vertical direction.

[0047] Furthermore, along the moving direction of the material, according to the different heating temperatures required for the material, n temperature zones are divided in the length direction of the belt system, and then:

[0048] V≤v×L n / (T n -T n-1 ) (4)

[0049] In the above formula (4), v is the carbonization heating rate, °C / min; L n is the length of each carbonization temperature zone of the belt system, m; T n is the temperature of each carbonization temperature zone of the belt system, ℃, and n is an integer greater than or equal to 2.

[0050] In general, the carbonization process includes drying, high temperature and insulation stages, and the belt carbonization furnace can be precisely temperature-controlled in sections (that is, according to the actual working conditions, the belt carbonization furnace is divided into multiple carbonization temperature zones along its length (the shorter the length of the carbonization temperature zone and the more the better, and it can be designed according to the actual working conditions), so that the temperature stability of each carbonization temperature zone in the length direction is generally ±0.5~1℃ / 24h, and the temperature difference of the effective vertical section of the material is generally ≤±1~3℃). Therefore, under the premise of stable temperature control of each section, it is of great significance to control the time and heating rate of the material in each carbonization temperature range.

[0051] It should be noted that all formulas in the present invention are obtained by fitting by the inventor based on experiments and engineering applications, and all calculations are numerical values ​​converted according to prescribed units, and are obtained by substituting the numerical values ​​after conversion into the formulas (after conversion of the units, only the numerical values ​​are substituted into the formulas for calculation, without substituting the units, and the units are only used to adjust the size of the numerical values).

[0052] In the present invention, in order to better achieve the drying of the activated carbon raw strips, the drying section can be set to a uniform temperature for drying, for example, the uniform drying temperature is 200-300°C. The drying section can also be set to be dried at a uniform temperature in sections, for example, the drying section is divided into a first drying section and a second drying section, wherein the uniform drying temperature of the first drying section is 150-300°C, and the uniform drying temperature of the second drying section is 250-400°C. Or the temperature of the sectioned drying is variable temperature drying with a temperature rise curve, for example, the inlet temperature of the first drying section is 150-200°C, and its outlet temperature is 200-300°C; the inlet temperature of the second drying section is 250-350°C, and its outlet temperature is 300-400°C.

[0053] In the present invention, in the carbonization section, in a preferred embodiment, the inlet temperature of the carbonization process is 350-500°C, the maximum temperature is 600-800°C; the temperature of the insulation section after the maximum temperature is 500-650°C; the carbonization time from the inlet of the carbonization process to the maximum temperature is 15-40 minutes, and the heating rate shall not exceed 15-20°C / min. A small amount of nitrogen can be introduced into the carbonization process for protection, and the pyrolysis gas generated by the carbonization process itself can also be used as a protective gas to prevent the activated carbon from igniting and burning.

[0054] In the present invention, a belt furnace is used as the carbonization equipment of activated carbon. The heating mode of the belt furnace can be heating the upper and lower sides at the same time or the left and right sides at the same time, or heating the upper and lower sides and the left and right sides at the same time. Before the belt furnace is distributed, the distribution thickness of the activated carbon raw material (i.e., raw material) is obtained by fitting calculation according to the activated carbon heat treatment process system, activated carbon ingredients, and activated carbon intermediate product (activated carbon carbonized material) indicators, so that the activated carbon raw material can be evenly and stably heated during drying, carbonization, heat preservation and other treatments in the belt furnace, which is conducive to quickly improving the pressure resistance and wear resistance of the activated carbon, and effectively ensuring the qualified rate and yield of the activated carbon finished product.

[0055] In the present invention, a sagger with through holes on the side wall and the bottom wall is used to hold a material box of activated carbon strips (strips, blocks or granules), and the sagger containing the activated carbon strips is placed on the conveyor belt of the belt furnace. It should be noted that in the present invention, the cloth thickness of the activated carbon strips refers to the cloth thickness of the activated carbon strips in a single sagger. Moreover, in the present invention, multiple rows of saggers can be placed side by side along the width direction of the belt furnace (i.e., the direction perpendicular to the direction of the material), and further, multiple layers of saggers can be stacked in the vertical direction. The number of rows and layers of the saggers placed during the cloth can be adjusted according to the actual working conditions.

[0056] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0057] 1: The present invention adopts a belt system as the activated carbon carbonization equipment. The activated carbon is in a static state throughout the whole process (relative to the material box), and the temperature difference of the effective vertical section of the material is lower than that of the carbonization rotary kiln, which greatly reduces the loss caused by broken materials due to mutual wear and force fracture of the activated carbon before a certain strength is formed, and improves the activated carbon carbonization yield.

[0058] 2: The present invention strictly controls the cloth thickness of the activated carbon raw strips and the running speed of the materials according to the thermal demand parameters of the carbonized materials and the finished product demand indicators, which greatly improves the heating uniformity of the activated carbon raw strips in the belt system and significantly reduces the loss of finished product output caused by substandard quality due to incomplete or excessive carbonization of the activated carbon product caused by uneven heating.

[0059] 3: The process of the present invention is simple and easy to operate. The activated carbon carbonization rate is increased by about 5-10% compared with the carbonization rotary kiln, the coefficient of variation of the compressive strength of the finished activated carbon product is reduced by about 10-20%, and the production capacity is greatly improved. It can be used alone with the Slep activation furnace, and has broad industrial application prospects and significant economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 It is a process flow chart of the present invention.

[0061] Figure 2 Schematic diagram of the fabric of a single-layer material box when fabric is distributed in the belt system of the present invention, wherein 2a is a front view and 2b is a side view.

[0062] Figure 3 Schematic diagram of fabric with multi-layer material box when fabric is laid in the belt system of the present invention, wherein 3a is a front view and 3b is a side view.

[0063] Figure 4 This is a schematic diagram of the structure of the sagger. DETAILED DESCRIPTION

[0064] The technical solution of the present invention is illustrated below by way of example, and the scope of protection requested by the present invention includes but is not limited to the following embodiments.

[0065] Example 1

[0066] An activated carbon carbonization method based on a belt system, the method comprising:

[0067] 1) According to the direction of the material, the belt system is divided into a distribution section, a drying section, a carbonization section and a heat preservation section. After the activated carbon strips are distributed in the distribution section, they are processed in the drying section, the carbonization section and the heat preservation section in turn to obtain the carbonized material.

[0068] 2) Before spreading, the thickness of the activated carbon strips is calculated based on the thermal demand parameters of the carbonized material and the finished product demand index. The activated carbon strips are spread in the spreading section according to the calculated thickness.

[0069] 3) The running speed of the activated carbon strips in the belt system is calculated based on the actual cloth thickness of the activated carbon strips, real-time thermal parameters and the target output of the carbonized material.

[0070] Example 2

[0071] Repeat Example 1, except that the method further comprises:

[0072] 4) The activated carbon carbonized material output from the belt carbonization furnace is cooled, and then protected by a protective gas to obtain a finished activated carbon.

[0073] Example 3

[0074] Example 2 was repeated, except that in step 1), the drying section was constant temperature drying at a drying temperature of 240°C.

[0075] Example 4

[0076] Example 2 was repeated, except that in step 1), the drying section was segmented constant temperature drying, the drying temperature of the first drying section was 180°C, and the drying temperature of the second drying section was 280°C.

[0077] Example 5

[0078] Example 2 was repeated, except that in step 1), the drying section was a segmented variable temperature drying, the inlet temperature of the drying section was 150°C, and the outlet temperature thereof was 300°C.

[0079] Example 6

[0080] Example 2 was repeated, except that in step 1), the carbonization stage was variable temperature carbonization, the inlet temperature of the carbonization stage was 300°C, and the outlet temperature of the carbonization stage was 650°C.

[0081] Example 7

[0082] Example 6 was repeated except that the heating rate in the carbonization stage was 12°C / min.

[0083] Example 8

[0084] Example 6 was repeated except that the heating rate in the carbonization stage was 15°C / min.

[0085] Example 9

[0086] Example 1 is repeated, except that in step 2), the thickness of the activated carbon strip is calculated based on the thermal demand parameters of the carbonized material and the finished product demand index: the thickness of the activated carbon strip is set to h, cm. Then:

[0087]

[0088] In the above formula (1), a is the correction coefficient, which is 12. J is the coal tar content, %. t T is the oxygen content in the carbonization stage, %. tmax is the highest temperature in the carbonization stage, °C. t is the heating time of carbonization stage, min. T1 is the inlet temperature of carbonization furnace, °C; t tb is the holding time of the highest temperature in the carbonization stage, min. t D is the wear resistance of carbonized material, and its value is ≥97%. t is the compressive strength of carbonized material, and its value is ≥450N. b is the correction constant, and its value is 0.

[0089] Example 10

[0090] Repeat Example 9, except that step 3) is specifically: the loading amount of a single material box is q, 2.5 kg, then:

[0091] q=ρ×h×A (2)

[0092] Assume that the running speed of the activated carbon strip in the belt system is V, m / min. Then:

[0093] V=Q×A 0.5 / (q×j×k) (3)

[0094] In the above formulas (2)-(3), ρ is the bulk density of the activated carbon strips in the material box, 600 kg / m 3 A is the material storage area of ​​a single material box, 0.09m 2 Q is the target output of carbonized material, 150 kg / min. j is the number of columns of the material boxes in the width direction of the belt system, j=3. k is the number of layers of the material boxes in the vertical direction, k=4.

[0095] Embodiment 11

[0096] Example 10 is repeated, except that n temperature zones are divided along the length direction of the belt system according to the different heating temperatures required for the materials along the moving direction of the materials, and then:

[0097] V≤v×L n / (T n -T n-1 ) (4)

[0098] In the above formula (4), v is the carbonization heating rate, °C / min; L n is the length of each carbonization temperature zone of the belt system, m; T n is the temperature of each carbonization temperature zone of the belt system, ℃, n=10.

[0099] Example 12

[0100] Example 11 was repeated, except that the material box was a rectangular sagger, and through holes were opened on the side wall and the bottom wall of the sagger. The depth of the sagger was twice the thickness of the cloth. The opening rate on the side wall of the sagger was 70%. The opening rate on the bottom wall of the sagger was 85%.

[0101] Example 13

[0102] Example 12 is repeated, except that the belt system is a belt furnace, and a plurality of temperature detectors are evenly arranged inside the belt furnace according to the direction of the material.

[0103] Embodiment 14

[0104] Example 13 was repeated, except that a protective gas supply device connected to the interior of the carbonization section was provided. The protective gas was nitrogen.

[0105] Application Examples

[0106] The activated carbon was carbonized using the method of Example 13, and the specific process parameters are shown in the following table:

[0107]

[0108]

Claims

1. An activated carbon carbonization method based on a belt system, characterized in that: The method includes: 1) According to the direction of the material, the belt system is divided into a distribution section, a drying section, a carbonization section and a heat preservation section; after the activated carbon raw strips are distributed in the distribution section, they are processed in the drying section, the carbonization section and the heat preservation section in turn to obtain the carbonized material; 2) Before spreading, the thickness of the activated carbon strips is calculated based on the thermal demand parameters of the carbonized material and the finished product demand index; and the activated carbon strips are spread in the spreading section according to the calculated thickness; 3) The running speed of the activated carbon strips in the belt system is calculated based on the actual cloth thickness of the activated carbon strips, the real-time thermal parameters and the target output of the carbonized material; Preferably, the method further comprises: 4) The activated carbon carbonized material output from the belt carbonization furnace is cooled, and then protected by a protective gas to obtain a finished activated carbon.

2. The method according to claim 1, characterized in that: In step 1), the temperature of the drying section is 150-400°C, preferably 180-350°C, more preferably 200-300°C; and / or In step 1), the temperature of the carbonization section is 350-800°C, preferably 400-750°C, more preferably 450-700°C; and / or In step 1), the temperature of the insulation section is 500-650°C, preferably 530-620°C, more preferably 550-600°C.

3. The method according to claim 1 or 2, characterized in that: The drying section is constant temperature drying or variable temperature drying; preferably, the drying section is segmented constant temperature drying or segmented variable temperature drying; Preferably, the drying section includes a first drying section and a second drying section, wherein: the inlet temperature of the first drying section is 150-200°C, and the outlet temperature of the first drying section is 200-300°C; the inlet temperature of the second drying section is 250-350°C, and the outlet temperature of the second drying section is 300-400°C.

4. The method according to any one of claims 1 to 3, characterized in that: The carbonization section is a variable temperature carbonization; preferably, the inlet temperature of the carbonization section is 350-500°C, and the outlet temperature of the carbonization section is 600-800°C; Preferably, the heating rate in the carbonization stage does not exceed 20°C / min, preferably 10-20°C / min; the carbonization time does not exceed 45min, preferably 15-40min.

5. The method according to any one of claims 1 to 4, characterized in that: In step 4), the activated carbon carbonized material is cooled by indirect water cooling and nitrogen direct cooling to ensure that the temperature of the activated carbon carbonized material after cooling is not higher than 50°C, preferably not higher than 30°C.

6. The method according to any one of claims 1 to 5, characterized in that: In step 2), the thickness of the activated carbon strip is calculated based on the thermal demand parameters of the carbonized material and the finished product demand index: the thickness of the activated carbon strip is set to h, cm; then: In the above formula (1), a is the correction coefficient, which is 8-12; J is the coal tar content, %; P t is the oxygen content in the carbonization stage, %; T tmax is the highest temperature of the carbonization stage, °C; t t is the heating time of carbonization stage, min; T1 is the inlet temperature of carbonization furnace, °C; t tb is the holding time of the highest temperature in the carbonization stage, min; w t D is the wear resistance of carbonized material, the value is ≥97%; t is the compressive strength of carbonized material, and its value is ≥450N; b is the correction constant, and its value is -2~2.

7. The method according to claim 6, characterized in that: Step 3) is specifically: the loading capacity of a single material box is q, kg, then: q=ρ×h×A (2) Assume that the running speed of the activated carbon strip in the belt system is V, m / min; then: V=Q×A 0.5 / (q×j×k) (3) In the above formulas (2)-(3), ρ is the bulk density of the activated carbon strips in the material box, kg / m 3 ; A is the material holding area of ​​a single material box, m 2 ; Q is the target output of carbonized material, kg / min; j is the number of columns of material boxes in the width direction of the belt system; k is the number of layers of material boxes in the vertical direction.

8. The method according to claim 7, characterized in that: Along the moving direction of the material, according to the different heating temperatures required for the material, there are n temperature zones divided along the length direction of the belt system, then: V≤v×L n / (T n -T n-1 ) (4) In the above formula (4), v is the carbonization heating rate, °C / min; L n is the length of each carbonization temperature zone of the belt system, m; T n is the temperature of each carbonization temperature zone of the belt system, ℃, and n is an integer greater than or equal to 2.

9. The method according to claim 7 or 8, characterized in that: The material box is a circular, rectangular or regular polygonal sagger, and through holes are provided on the side wall and the bottom wall of the sagger; the depth of the sagger is 1.2-4 times the thickness of the cloth, preferably 1.5-3 times.

10. The method according to claim 9, characterized in that: The opening rate on the side wall of the sagger is not less than 50%, preferably 55-95%, more preferably 60-80%; and / or The opening rate on the bottom wall of the sagger is not less than 60%, preferably 65-90%, more preferably 70-85%.

11. The method according to any one of claims 1 to 10, characterized in that: The belt system is a belt furnace, and a plurality of temperature detectors are evenly arranged inside the belt furnace according to the direction of the material; and / or A protective gas supply device connected to the interior of the carbonization section is provided; the protective gas is an inert gas or nitrogen, preferably nitrogen.

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