Method for producing briquetted activated carbon by drying raw coal with waste heat

Abstract

The invention relates to the technical field of activated carbon production, in particular to a method for producing briquetted activated carbon after drying raw coal by waste heat, which comprises the following steps: crushing and screening the raw coal, collecting tail gas generated in a carbonization stage for incineration, and drying raw coal particles by using hot air after heat exchange of high-temperature flue gas until the moisture is lower than 5%; grinding the dried material, mixing the ground dried material with a binder according to a ratio of 100: (5-10), carrying out compression molding, and carrying out carbonization treatment under the protection of inert gas to form a carbonized material; and then activating with an activating agent of which the mass is 1-3 times that of the activated carbon at 600-900 DEG C for 1-2 hours, washing with deionized water to be neutral, drying in an environment with the temperature of 100-120 DEG C, and finally screening to obtain a finished product of activated carbon with a specific particle size. Raw coal is dried by recycling heat energy of carbonized tail gas, the drying efficiency is remarkably improved, the device is particularly suitable for cold areas in winter, carbonized tail gas resources are fully utilized, environmental protection benefits are remarkable, and meanwhile high-yield and high-efficiency production of granular activated carbon is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of activated carbon production, and in particular to a method for producing briquette activated carbon by drying raw coal with waste heat. Background Art

[0002] Activated carbon is a porous carbon material with high specific surface area and developed pore structure, which is widely used in environmental protection, chemical industry, food, medicine and other fields. In the traditional activated carbon production process, the drying and briquetting of raw coal are key steps, especially in cold winter areas such as Xinjiang. The low temperature environment has a great impact on the drying efficiency of raw coal, resulting in increased energy consumption and rising production costs.

[0003] In addition, the carbonized tail gas generated during the production of activated carbon is usually directly discharged or simply treated, and its thermal energy value is not fully utilized. Therefore, developing a method of producing briquette activated carbon by using the waste heat from the incineration of carbonized tail gas to exchange heat with air and then drying the raw coal with hot air can not only improve energy utilization efficiency, but also reduce production costs, which has important economic and environmental significance. Summary of the invention

[0004] In view of the shortcomings of the prior art, the present invention provides a method for producing briquette activated carbon by drying raw coal with waste heat, which solves the problem that the carbonized tail gas in the activated carbon production process is not fully utilized.

[0005] To achieve the above purpose, the present invention is implemented by the following technical scheme: a method for producing briquette activated carbon by drying raw coal with waste heat, comprising the following steps:

[0006] S1. Raw coal pretreatment

[0007] Use a crusher to crush the raw coal into particles with a particle size of 1-5 mm, and perform preliminary screening on the raw coal particles to remove impurities;

[0008] S2. Carbonization tail gas recovery and incineration

[0009] Collect the tail gas generated during the carbonization process and introduce it into the incinerator for incineration to produce high-temperature flue gas;

[0010] S3. Raw coal drying

[0011] The high-temperature flue gas generated during incineration is used to dry the raw coal particles through air heat exchange, and the moisture content of the raw coal is controlled below 5%;

[0012] S4. Briquetting

[0013] The dried raw coal particles are ground into powder using a grinding device and then mixed with a binder in a mass ratio of 100:(5-10), and after the mixture is evenly mixed, the mixture is pressed into a briquetting machine to obtain a briquette;

[0014] S5. Carbonization

[0015] Putting the briquette material into a carbonization furnace and introducing inert gas to heat and carbonize the material to obtain briquette carbonized material;

[0016] S6. Activation treatment

[0017] The briquette carbonized material and the activator are mixed in a mass ratio of 1:(1-3), and activated at 600-900°C for 1-2 hours to obtain an activated material;

[0018] S7.Washing and drying

[0019] The activated material is repeatedly washed with deionized water until it becomes neutral, and then dried at 100-120°C to obtain granular activated carbon;

[0020] S8. Post-processing

[0021] The dried granular activated carbon is sieved to obtain finished activated carbon with the required particle size.

[0022] Preferably, in step S3, the drying temperature is 100-150° C., and the drying time is 1-2 hours.

[0023] Preferably, in step S4, the binder includes but is not limited to any one of coal tar, coal pitch and starch.

[0024] Preferably, in the step S5, the carbonization temperature is 500-700° C., and the carbonization time is 1-3 hours.

[0025] Preferably, in step S6, the activator includes but is not limited to any one of potassium hydroxide and phosphoric acid.

[0026] The present invention provides a method for producing briquette activated carbon by drying raw coal with waste heat. It has the following beneficial effects:

[0027] 1. The present invention recycles the heat energy of carbonization tail gas to dry the raw coal, significantly improving the drying efficiency and reducing energy consumption. It is particularly suitable for cold areas in winter, making full use of carbonization tail gas resources, with significant environmental benefits, and achieving high-yield and high-efficiency production of granular activated carbon. At the same time, the briquetting process improves the density and strength of the raw coal, which is conducive to the subsequent carbonization and activation process. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] Embodiment 1:

[0030] The embodiment of the present invention provides a method for producing briquette activated carbon by drying raw coal with waste heat, comprising the following steps:

[0031] S1. Raw coal pretreatment

[0032] Use a crusher to crush the raw coal into particles with a particle size of 5 mm, and perform preliminary screening on the raw coal particles to remove impurities;

[0033] S2. Carbonization tail gas recovery and incineration

[0034] The tail gas generated during the carbonization process is collected and introduced into the incinerator for incineration to produce high-temperature flue gas. When the carbonized tail gas is incinerated, the temperature of the incinerator is controlled at 1000°C to ensure that the combustible components in the tail gas are fully burned;

[0035] S3. Raw coal drying

[0036] The high-temperature flue gas generated during incineration is used to dry the raw coal particles through air heat exchange, and the moisture content of the raw coal is controlled below 5%. During the drying process, indirect heating is used to avoid direct contact between the high-temperature flue gas and the raw coal, which can prevent oxidation of the raw coal.

[0037] S4. Briquetting

[0038] The dried raw coal particles are ground into powder using a grinding device and then mixed with a binder in a mass ratio of 100:10. After the mixture is evenly mixed, it is pressed into a briquetting machine to obtain a briquette;

[0039] S5. Carbonization

[0040] Putting the briquette material into a carbonization furnace and introducing inert gas to heat and carbonize the material to obtain briquette carbonized material;

[0041] S6. Activation treatment

[0042] The briquette carbonized material and the activator are mixed in a mass ratio of 1:3, and activated at 900° C. for 2 hours to obtain an activated material;

[0043] S7.Washing and drying

[0044] The activated material is repeatedly washed with deionized water until it becomes neutral, and then dried at 120°C to obtain granular activated carbon;

[0045] S8. Post-processing

[0046] The dried granular activated carbon is sieved to obtain finished activated carbon with the required particle size.

[0047] In step S3, the drying temperature is 150° C. and the drying time is 2 hours.

[0048] In step S4, the binder includes but is not limited to any one of coal tar, coal pitch and starch.

[0049] In step S5, the carbonization temperature is 700° C. and the carbonization time is 3 hours.

[0050] In step S6, the activator includes but is not limited to any one of potassium hydroxide and phosphoric acid.

[0051] Embodiment 2:

[0052] The embodiment of the present invention provides a method for producing briquette activated carbon by drying raw coal with waste heat, comprising the following steps:

[0053] S1. Raw coal pretreatment

[0054] Use a crusher to crush the raw coal into particles with a particle size of 1 mm, and perform preliminary screening on the raw coal particles to remove impurities;

[0055] S2. Carbonization tail gas recovery and incineration

[0056] The tail gas generated during the carbonization process is collected and introduced into the incinerator for incineration to produce high-temperature flue gas. When the carbonized tail gas is incinerated, the temperature of the incinerator is controlled at 800°C to ensure that the combustible components in the tail gas are fully burned;

[0057] S3. Raw coal drying

[0058] The high-temperature flue gas generated during incineration is used to dry the raw coal particles through air heat exchange, and the moisture content of the raw coal is controlled below 5%. During the drying process, indirect heating is used to avoid direct contact between the high-temperature flue gas and the raw coal, which can prevent oxidation of the raw coal.

[0059] S4. Briquetting

[0060] The dried raw coal particles are ground into powder using a grinding device and then mixed with a binder in a mass ratio of 100:5, and after the mixture is evenly mixed, the mixture is pressed into a briquetting machine to obtain a briquette;

[0061] S5. Carbonization

[0062] Putting the briquette material into a carbonization furnace and introducing inert gas to heat and carbonize the material to obtain briquette carbonized material;

[0063] S6. Activation treatment

[0064] The briquette carbonized material and the activator are mixed in a mass ratio of 1:1, and activated at 600°C for 1 hour to obtain an activated material;

[0065] S7.Washing and drying

[0066] The activated material is repeatedly washed with deionized water until it becomes neutral, and then dried at 100°C to obtain granular activated carbon;

[0067] S8. Post-processing

[0068] The dried granular activated carbon is sieved to obtain finished activated carbon with the required particle size.

[0069] In step S3, the drying temperature is 100° C. and the drying time is 1 hour.

[0070] In step S4, the binder includes but is not limited to any one of coal tar, coal pitch and starch.

[0071] In step S5, the carbonization temperature is 500° C. and the carbonization time is 1 hour.

[0072] In step S6, the activator includes but is not limited to any one of potassium hydroxide and phosphoric acid.

[0073] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for producing briquette activated carbon by drying raw coal with waste heat, characterized in that: The following steps are involved: S1. Raw coal pretreatment Use a crusher to crush the raw coal into particles with a particle size of 1-5 mm, and perform preliminary screening on the raw coal particles to remove impurities; S2. Carbonization tail gas recovery and incineration Collect the tail gas generated during the carbonization process and introduce it into the incinerator for incineration to produce high-temperature flue gas; S3. Raw coal drying The high-temperature flue gas generated during incineration is used to dry the raw coal particles through air heat exchange, and the moisture content of the raw coal is controlled below 5%; S4. Briquetting The dried raw coal particles are ground into powder using a grinding device and then mixed with a binder in a mass ratio of 100:(5-10), and after the mixture is evenly mixed, the mixture is pressed into a briquetting machine to obtain a briquette; S5. Carbonization Putting the briquette material into a carbonization furnace and introducing inert gas to heat and carbonize the material to obtain briquette carbonized material; S6. Activation treatment The briquette carbonized material and the activator are mixed in a mass ratio of 1:(1-3), and activated at 600-900°C for 1-2 hours to obtain an activated material; S7.Washing and drying The activated material is repeatedly washed with deionized water until it becomes neutral, and then dried at 100-120°C to obtain granular activated carbon; S8. Post-processing The dried granular activated carbon is sieved to obtain finished activated carbon with the required particle size.

2. The method for producing briquette activated carbon by drying raw coal with waste heat according to claim 1, characterized in that: In the step S3, the drying temperature is 100-150° C. and the drying time is 1-2 hours.

3. The method for producing briquette activated carbon by drying raw coal with waste heat according to claim 1, characterized in that: In the step S4, the binder includes but is not limited to any one of coal tar, coal pitch and starch.

4. The method for producing briquette activated carbon by drying raw coal with waste heat according to claim 1, characterized in that: In the step S5, the carbonization temperature is 500-700° C., and the carbonization time is 1-3 hours.

5. The method for producing briquette activated carbon by drying raw coal with waste heat according to claim 1, characterized in that: In the step S6, the activator includes but is not limited to any one of potassium hydroxide and phosphoric acid.