Activated carbon plays a significant role in the deep purification of municipal drinking water, and is effective in removing a large number of water-soluble organic pollutants (DOC), odour and ammonia nitrogen. Activated carbon adsorption method to remove pollutants in water. Generally, choose coal granular activated carbon. We can judge the quality of activated carbon according to iodine value, methylene blue value, but coal activated carbon according to the production process is not necessary, can be divided into agglomerated and directly crushed granular activated carbon.

The following is the difference between the two:

1. Production process:

Compared with columnar activated carbon, tar is not used as binder in the production process, and it is directly pressed by coal blending and milling, and then crushed and divided into different particle sizes according to the needs after carbonisation and activation. Since no tar is used in the production process of briquetted granular activated carbon, it is less polluting. Raw coal crushed granular activated carbon is made by directly charring and activating raw coal and then crushing it into different sizes according to the demand.

2. Surface structure under microscope:

The surface of coal-based activated carbon made by re-agglomerated method is rougher than the rounded surface of raw coal directly crushed carbon, and microorganisms are easier to attach and produce on its surface. As shown in the following picture, the scanning electron microscope shows the surface morphology of briquette crushed granular activated carbon and raw coal direct crushed carbon into biofilm under the condition of applying ozone-bioactivated carbon process, respectively. The surface of the briquette crushed granular carbon is very rough under magnified conditions and there are colonies formed, like a porous sponge, while the raw coal directly crushed carbon can be seen that the surface is relatively smooth, unlike the briquette crushed granular carbon where there are a large number of colonies formed on the surface.

3. Pore volume and pore structure distribution:

Activated carbon pore volume and pore structure distribution uniformity determines the regulation to the microbial food supply capacity, through the coal method for the briquette crushing activated carbon pore volume and pore size distribution regulation than the original coal crushing granular activated carbon is stronger.

4. Floatation rate

The floatation rate of coal-based activated carbon produced by the briquetting method is much lower than that of directly crushed activated carbon from raw coal. In liquid phase adsorption applications (e.g., water treatment), activated carbon with a high floatation rate tends to collect on the liquid surface rather than being evenly distributed in the water column. This reduces the contact area of the activated carbon with the pollutant and affects the adsorption effect.

5. Bulk density

The stack density of briquette crushed granular activated carbon is higher than that of raw coal directly crushed activated carbon, and the stack density of activated carbon will affect the backwash efficiency, thermal regeneration efficiency and the amount of product put into the filter at one time. Because the input of activated carbon into the filter is measured by volume, while sales and purchases are calculated by mass, i.e. a higher density means a more activated carbon product per unit volume. Higher density activated carbon can withstand faster backwash water flow rates and has better performance recovery during regeneration.

6. Strength:

Briquetted granular activated carbon is stronger than raw coal direct crushed activated carbon, and activated carbon with high hardness and abrasion strength has lower losses during transport, conveying, backwashing and regeneration. If a high temperature thermal regeneration process is used, the strength is very important for the reproduction rate, which saves costs.

Conclusion

To sum up, the performance of briquette crushed granular activated carbon in municipal drinking water application is much higher than that of raw coal direct crushing activated carbon, although the price is higher than that of raw coal direct crushing activated carbon, but in terms of the service life and purification effect, its cost-effectiveness is still higher than that of raw coal direct crushing activated carbon.

Huamei Activated Carbon is one of the top 10 activated carbon manufacturers in China, with rich experience in activated carbon production and extensive product application knowledge, we provide professional purchasing advice and services for activated carbon buyers all over the world, if you have any questions about activated carbon, please contact us.

Coal-based columnar activated carbon is a material with excellent adsorption properties and is widely used in many fields such as air purification, water treatment, gas separation, chemical catalysis, etc. The manufacturing process of coal-based columnar activated carbon is a complex industrial process involving multiple steps from the selection of raw materials to the inspection of the final product. This article will introduce in detail the manufacturing process of coal-based columnar activated carbon to help you understand the production of this material and its excellent properties.

1. Raw material selection

The main raw material of coal-based columnar activated carbon is coal, usually bituminous coal or anthracite coal. Bituminous coal contains higher fixed carbon and is suitable for producing high-strength columnar activated carbon; anthracite coal, due to its lower ash content and higher porosity, is suitable for producing activated carbon with low ash content and high adsorption performance. The choice of coal directly affects key indicators such as pore structure, specific surface area, and adsorption capacity of the final product.
In the process of selecting coal, activated carbon manufacturers will carefully select suitable coal sources based on market demand and the requirements of different applications. Generally speaking, the source of raw coal, coal quality characteristics, ash content, moisture content, etc. will affect the final quality of coal-based columnar activated carbon. As we all know, the best raw material for columnar carbon is produced in Ningxia. Our Ningxia Huamei activated carbon factory is only 60 kilometers away from the anthracite coal mine, which greatly reduces transportation costs.

2. Grinding and shaping

Before making coal-based columnar activated carbon, coal needs to be ground into powder, mixed with a certain proportion of coal tar and water to form a paste, and then extruded. Finally dry.
In the process of selecting tar, different manufacturers will choose according to market demand. Some manufacturers even use other binders to replace tar in order to reduce costs, but the activated carbon produced will have some quality problems. Our Ningxia Huamei activated carbon factory insists on using high-quality coal tar and strictly follows the best production technology to provide customers with high-quality products.

3. Arbonization process

Carbonization is one of the key steps in the production process of coal-based columnar activated carbon. At this stage, the dried coal is heated to a certain temperature (usually 600-900°C), and the heating reaction is carried out in an oxygen-free or oxygen-deficient environment. This process converts organic matter in coal into carbon black and releases moisture and volatile matter.
The purpose of carbonization is to remove volatile matter from coal through high temperature so that the remaining solid carbon becomes a porous structure with a large specific surface area. The control of this step is crucial, as temperature that is too high or too low may affect the quality of the final product. And it will affect the length of the carbon.

4. Activation process

Activation is the most important process step in the manufacture of coal-based columnar activated carbon, which directly determines the pore structure and adsorption performance of the carbon. During the activation process, the carbonized coal comes into contact with water vapor at high temperatures, which further opens the pores in the coal through physical reactions to form activated carbon with a high specific surface area and porous structure.

5. Drying and cooling

The activated columnar activated carbon needs to be cooled. The columnar activated carbon will gradually cool down to room temperature through cooling equipment to ensure its stability.

6. Screening and classification

After cooling, the activated carbon particles undergo dust removal screening to separate particles of different sizes. The purpose of screening is to ensure the consistency of the final product and ensure that activated carbon particles of different particle sizes can meet the needs of different customers. Normally, the Ningxia Huamei activated carbon factory will carry out dust removal three times to ensure the cleanliness of the activated carbon.
Depending on different uses and requirements, coal-based columnar activated carbon may be classified according to particle size. For example, some applications require smaller particle sizes, while other applications require larger particles to enhance flow rates and adsorption efficiency.

7. Quality Control and Packaging

In the final stage of coal-based columnar activated carbon manufacturing, strict quality testing is required. These tests include CTC, iodine value, ash content, mechanical strength, particle size distribution, etc. Ensure that each batch of coal-based columnar activated carbon meets industry standards and customer needs.
After passing quality inspection, qualified activated carbon products will be packaged. When packaging, activated carbon needs to be stored sealed to avoid moisture absorption or contamination to ensure its stability and adsorption performance.

8. Application areas

Coal-based columnar activated carbon is widely used in the following fields due to its excellent adsorption performance and structural stability:
·Gas adsorption: such as air purification, waste gas treatment, biogas desulfurization, etc.
·Water treatment: such as drinking water purification, wastewater treatment, etc.
·Solvent recovery: such as the recovery and reuse of chemical solvents.
·Gas separation: such as oxygen, nitrogen separation, etc.

Summarize

The manufacturing process of coal-based columnar activated carbon is a highly specialized technical process that requires strict control of raw material selection, carbonization, activation, molding and other links. Through these fine processes, the final product can meet the needs of different application fields and has extremely high adsorption capacity, durability and structural stability. As the market's demand for environmental protection and energy conservation increases, the application prospects of coal-based columnar activated carbon in multiple industries will become broader.

1. Adsorption Principle

Activated carbon air purification belongs to the field of adsorption. Adsorption is caused by the force between the molecules of the adsorbent and the adsorbate. According to the different forces, it can be divided into physical adsorption and chemical adsorption.
Physical adsorption mainly relies on van der Waals forces between molecules. Physical adsorption simply relies on the attraction between molecules to adsorb the adsorbate on the surface of the adsorbent.
Physical adsorption is reversible. By lowering the partial pressure of the adsorbate in the gas phase and increasing the adsorption temperature, the adsorbate will desorb quickly without changing its chemical composition.
Chemical adsorption relies on the chemical bonding force between the solid surface and the adsorbed gas molecules.
It is the result of chemical action. Its force greatly exceeds the van der Waals force of physical adsorption. It is often an irreversible process. Chemical adsorption has high selectivity. It is a kind of adsorption. The agent only adsorbs specific substances.

After adsorption, the adsorbate has changed and its original characteristics have been changed. Adsorbing adsorbate on the surface of the adsorbent is a reversible process, which can only temporarily block pollution but cannot eliminate it. Moreover, the rate of chemical adsorption increases with increasing temperature. It is worth noting that the same substance may undergo physical adsorption at lower temperatures, while chemical adsorption may occur at higher temperatures, or both adsorption methods may occur at the same time.

 

The physical adsorption process can be divided into the following steps:
(1) The pollutant gas passes through the adsorption boundary layer. The molecules of the pollutant gas may be adsorbed or taken away from the surface of the activated carbon, depending on the concentration difference of the component in the carrier gas and the gas in the boundary layer.
This value determines The strength of adsorption. When polluted air passes through activated carbon, some harmful gases have a large concentration difference, so they are adsorbed. However, the inherent components in the air pass normally because the concentration difference is basically zero, while some particles (such as smoke) are too large. They are left directly in the macropores and mesopores. When the concentration difference of harmful gases reaches zero, the activated carbon fails and needs to be reactivated.

(2) The adsorbed molecules diffuse into the micropores.

(3) The molecule is firmly bound to the adsorbent surface.

The chemical adsorption of activated carbon mainly relies on the chemical components on the material to react with pollutants to generate solid components or harmless gases. Activated carbon can also be subjected to some chemical treatments, such as adding some catalysts, which can help decompose harmful gases such as formaldehyde, VOCs, etc.

During use, the adsorption capacity will continue to weaken. When it weakens to a certain extent, the filter will be scrapped. The pore diameter of activated carbon used to purify the air must be slightly larger than the diameter of toxic and harmful gas molecules to have the ability to adsorb toxic and harmful gases. The key factors that affect the service life of air purification activated carbon: the total amount of harmful substances in the environment and the frequency of desorption.
Since the quality of activated carbon adsorbing harmful gases can be close to or even reach its own quality, the quality of harmful gases in the air of ordinary household spaces is far less than the amount of activated carbon used.
Therefore, activated carbon can be used for a long time as long as it is regularly exposed to the sun. Of course, dust blocking the micropores of activated carbon will also reduce its adsorption capacity.

2. Adsorption Performance

(1) Adsorption capacity: The maximum amount of pollutants that a unit of activated carbon can adsorb is called adsorption capacity. The adsorption capacity of different materials will be different; the adsorption capacity of the same material for different gases will also be different; the adsorption capacity will also change when the temperature and background concentration change.

(2) Residence time: The time that air stays in the activated carbon layer is called residence time. The longer the residence time, the more complete the adsorption. In order to maintain sufficient retention time, the carbon layer must be thick enough and the filtration wind speed must be as low as possible.

(3) Service life: New activated carbon has high adsorption efficiency, but the efficiency continues to decrease during use. When harmful gases downstream of the filter approach the allowable concentration limit, the filter is scrapped. The usage time before scrapping is the service life, also known as the effective protection time.

(4) Selectivity: Generally speaking, the gases that are easily adsorbed in physical adsorption include: gases with large molecular weights, gases with high boiling points, and volatile organic gases. If activated carbon is chemically impregnated, it can also remove gases that are usually difficult to deal with, or enhance the adsorption capacity for certain types of gases.

Huamei Activated Carbon has launched several activated carbon products: activated carbon filter screen and honeycomb activated carbon, which are specially used for air purifier equipment. They have remarkable effects and favorable prices. Welcome to contact us for inquiries.

Nowadays, environmental protection has become a global concern, and countries all over the world, especially some developed regions, pay much attention to the prevention of environmental pollution. Therefore, in the case of people's awareness of environmental protection is gradually strengthened, the discharge of wastewater and recycled water quality requirements are also increasingly high.

The Application Of Coconut Shell Activated Carbon In Water Treatment

1. For the purification of sewage, the use of coconut shell activated carbon adsorption of organic matter in water, color, odor and deodorization. Color, deodorization and deodorization. Because the depth purification method of coconut shell activated carbon can effectively improve the water quality, domestic and foreign in the new water plant basically use this method.

2. In the organic industrial wastewater treatment, due to the coconut shell activated carbon on the water of organic substances such as cod has outstanding removal ability. For some difficult to be degraded organic matter has a unique removal effect, which is used in tannery wastewater treatment, paper dye chemical wastewater treatment, coking wastewater treatment and other organic wastewater treatment.

3. Inorganic industrial wastewater treatment, some adsorption activated carbon has certain selective adsorption function for inorganic heavy metal ions in wastewater. For example, the adsorption and removal rate of granular activated carbon for plasma can reach more than 86%, and it has good adsorption effect on other metal ions such as mercury, lead and iron. In addition, the adsorption effect of coconut shell activated carbon on cl2.br2.i2 in water is also very strong.

Coconut Shell Activated Carbon For Water Treatment

On the basis of the continuous progress of water treatment technology, countries around the world are studying the use of coconut shell activated carbon for water treatment in cooperation with other methods. In order to improve the quality of water, the combined method of treatment is more effective, filling the phenomenon of high wastewater treatment costs due to the frequent use of regeneration of coconut shell activated carbon. Its solution has the following ways:

Powdered activated carbon treatment: it is in the absorption as well as microbial oxidation and decomposition of the joint cooperation to remove pollutants. The porous coconut shell activated carbon absorbs the organic matter and oxygen in the wastewater, supplying high-quality nutrient source for microorganisms to grow and reproduce, and the microorganisms produce colloidal substances in the process of growth, which are absorbed and collected in the fine pores of coconut shell activated carbon. In addition, the biological and organic matter on the charcoal contact time is relatively long, so that the original difficult to degrade organic matter will also be decomposed.

Coconut shell activated carbon treatment method: it is the ozone oxidation, coconut shell activated carbon will be a combination of the two methods, but also easier to let the coconut shell activated carbon adsorption, for the dyes of the wastewater of the killing, deodorization, and decolorization ability is significant and extends the coconut shell activated carbon use time.

Coconut shell activated carbon adsorption method: This method is to use coconut shell activated carbon for organic compounds collection effect and selective adsorption of dissolved oxygen in water. When the temperature and nutrition are suitable, microorganisms will grow on the surface layer of coconut shell activated carbon, so that the adsorption function of coconut shell activated carbon can cooperate with the oxidative decomposition of microorganisms. In this way, not only can improve the efficiency of wastewater treatment, but also can make the use of coconut shell activated carbon time to extend a lot, but also reduces the cost, easy to run the implementation of management, which is a newly developed sewage treatment technology.

As a professional manufacturer and supplier of Coconut Shell Activated Carbon, we have rich manufacturing experience and R&D capability. Meanwhile, our strict quality management system ensures that we have received wide acclaim among our customers. Contact Huamei Activated Carbon, we will provide you with perfect service.

Huamei Activated Carbon received the following email from a metallurgist in Burkina Faso gold mine in 2024/11/08 asking for help:

Hello Sir! I read your article on the properties of high quality activated carbon. I am a metallurgist at a mine in Burkina Faso and we are currently experiencing serious problems with an activated coal used for gold adsorption. This carbon has a very low density and is not homogeneous in the leaching reactor. When we measure the carbon concentration in the slurry, it is always higher than we should expect. We had to mix two types of coal in the reactor, one HAYCARB and the other CO-PROCHIM, the latter being a local activated carbon and the other an imported one. As far as gold adsorption efficiency is concerned, the latter has a lower density and all the activated carbon floats on the surface, resulting in a decrease in gold adsorption activity. I would like to get some suggestions. Our treatment process is CIL and gravity method.

In response to the customer's question, Huamei carbon's technical team made a careful analysis and gave friendly advice as follows:

CO-PROCHIM activated carbon's floats on the surface in the leaching reactor, which reduces the contact efficiency with the slurry and thus affects the gold adsorption efficiency. In order to solve this problem, the following aspects can be optimised:

1. Ratio and optimisation of HAYCARB and CO-PROCHIM mixed carbon

a. Adjust the mixing ratio of carbon appropriately

Enhance the proportion of HAYCARB: According to your description, increasing the proportion of HAYCARB in the mixture may improve the adsorption effect. It is recommended that you find the optimal ratio by first testing it in small-scale experiments and gradually increasing the proportion of HAYCARB (e.g. 70% HAYCARB + 30% CO-PROCHIM).
Adjust the ratio according to the mineral composition: different minerals have different reactivity, you can further optimise the mixing ratio according to the type of ore, the pH value of the slurry and the leaching rate of gold to ensure the optimal adsorption rate of gold.

b. Mixing method and agitation of activated carbon

Uniformity: Use suitable mechanical mixing equipment to ensure that CO-PROCHIM and HAYCARB can be evenly distributed in the slurry, to avoid CO-PROCHIM activated carbon gathering on the surface.
Adjustment of mixing rate: Increase the mixing rate or install specific mixers to ensure better distribution of activated carbon in the slurry.

2. CIL process optimisation

a. Optimisation of the leaching reactor design

Ensure a balance between flow rate, agitation and char mobility in the CIL reactor to prevent char particles from accumulating in the reactor. Reactors with agitation or agitation tower design can be used to enhance the contact between the char and the slurry.
Dividing the CIL leaching process into multiple stages, using different char concentrations and agitation rates for each stage, may help to improve leaching and gold recovery.

b. Ensure that the contact time between the activated carbon and the gold ore slurry is sufficient during the leaching process. At the same time, increase the temperature and slurry concentration appropriately during the adsorption process to improve the adsorption efficiency of gold.

3. Optimisation of activated carbon

Raw material selection of activated carbon: During the production process, heavier raw material coconut shell is needed to increase the quality and density of carbon.
Adjustment of production process: The problem of low density of CO-PROCHIM activated carbon may originate from its sintering process. The activation temperature of the charcoal can be increased or the activation activity can be changed to increase the density of the activated charcoal. The activation temperature affects the pore structure and density of the carbon and needs to be strictly regulated.
Optimisation of particle size distribution and particle morphology: Low-density chars tend to have smaller pore sizes, which may cause them to float to the surface in leach reactors. The settling properties can be enhanced by adjusting the particle size distribution of the particles, especially by increasing the proportion of particles.
For gold recovery, choosing the right activated carbon is crucial. If the quality of the carbon is poor, not only will it be ineffective, but it will also lead to gold loss, which will result in significant losses.

Huamei Activated Carbon Company is a professional manufacturer of coconut shell activated carbon with more than 50 stable cooperation customers in the field of gold refining in Egypt, Sudan, Libya, Tanzania, Burkina Faso, Ghana, Turkey, Uzbekistan, Hong Kong, Kyrgyzstan and other countries. Huamei Activated Carbon has been well received, if you need activated carbon, please feel free to contact us!