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How to effectively capture pollutants by activated carbon

Many municipal drinking water and wastewater plants use activated carbons to purify water and air leaving the plant. Activated carbon is not a subject you learn about in school — you learn on the job.

 At present, activated carbon in its various forms has more than 2,500 commercial applications. activated carbon manufacturer  Operators of facilities that use activated carbon can benefit from a better understanding of what it is, how it works and how to use it most effectively.

 Activated carbon is an inert, solid, adsorbent material that can remove many dissolved contaminants from water and process gas streams. It can be made from almost any feedstock that contains carbon; for municipal plants these mainly include wood, coconut shells and coal. Activated carbons are inexpensive and readily available. Being highly porous, they provide a large surface area to remove contaminants: One teaspoon has more surface area than a football field.

 Activated carbon is especially effective for capture of contaminants that impart taste, odor, color and toxicity. Contaminants adsorb on the surface of the carbon particles in tiny pores and are thus pulled out of solution.https://www.dxdcarbon.com/

 Activated carbon manufacturers can provide a variety of pore size distributions by using different feedstocks and process parameters. Proper pore structure selection is the key to effective activated carbon treatment.

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What are the types and the uses of activated carbon

Activated Carbon is also known as Activated Charcoal and is produced from carbonaceous, a highly porous adsorptive medium that has a complex structure composed primarily of carbon atoms. Activated carbons are manufactured from coconut shell, peat, hard and softwood, lignite coal, bituminous coal, olive pits, and various carbonaceous specialty materials. activated carbon suppliers in china  Chemical activation or high-temperature steam activation mechanism are used in the production of activated carbons from these raw materials. The chemical structure of activated carbon can be defined as a crude form of graphite, with a random amorphous structure that is highly porous over a wide range of pore sizes, from visible cavities and gaps of molecular dimensions.

 Granular Activated Carbon (GAC)

 Granular activated carbon is defined as the activated carbon being retained on a 50-mesh sieve. They have the advantages of being harder and more long-lasting than powder activated carbon (PAC), clean to handle, purify larger volumes of gas or liquid of a consistent quality, and can be reactivated and reused many times.  

 Granules Activated Carbon is widely used in drinking water, industrial water, brewing, waste gas treatment, decolorization, desiccant, gas purification, etc.

 Powdered Activated Carbon (PAC)

 Powdered activated carbon (PAC) is made from organic materials with high carbon contents such as wood, lignite, and coal. PAC typically has a diameter of less than 0.1 mm and has an apparent density range between 23 and 46 lb/ft3. Advantages of powdered activated carbons are their lower processing costs and their flexibility in operation

 Powder carbons are widely used in food, beverage, medicine, tap water, sugar, oil and other industries in brewing, sewage, treatment, power plants, electroplating, etc.

 Pellets

 Pellets are activated carbon compressed into a cylindric shape and have a wide variety of uses. activated carbon for gold mining  Removing contaminants such as volatile organic compounds (VOCs) and mercury from natural gas as well as controlling odour. Pelletized activated carbon is made from high-quality coal or coconut shell by extruding the activated carbon into cylindrical particles with a diameter range of 0.9 – 8 mm.

 Activated carbon pellets are suitable for toxic gas purification, waste gas treatment, industrial and domestic water purification treatment.

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How can activated carbon be used？

Activated carbon is commercially manufactured from coal, wood, fruit stones (mainly coconut but also walnut, peach) and derivatives of other processes (gas raffinates). Of these coal, wood and coconut are the most widely available.

 The product is manufactured by a thermal process, but in the case of raw materials such as wood, a promoter (such as an acid) is also used to develop the required porosity.

 Downstream processes crush, screen, wash and/or grind the multitude of products to the client’s requirements.

 How an activated carbon is used depends very much on the application duty, and its form. buy activated charcoal bulk  For example, powdered activated carbon (PAC) is used to treat drinking water, by simply adding the required amount directly to the water and then separating the resulting coagulation matter (as well as other solids) before sending the treated water to the network. The contact with the organics present results in adsorption of them and the purification of the water.

 Granular carbons (or extruded pellets) are used in fixed filter beds, with the air, gas or liquid passing through it with a determined residence (or contact) time. yrd carbon  During this contact the unwanted organics are removed and the treated effluent is purified.

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What role does activated carbon play in a water purifier

Activated carbon can remove water smell and taste, color, residual chlorine, colloids, organic matter (synthetic detergents, pesticides, herbicides, insecticides, synthetic dyes, trihalomethanes, haloacetic acids, endocrine disruptors such as phthalic acid) Ester PAES, etc.), heavy metals (such as mercury, silver, cadmium, chromium, lead, nickel, etc.), radioactive substances, etc., are the earliest and most widely used water purification materials in water purifiers. wholesale carbon pellets  Activated carbon is used not only in general activated carbon water purifiers, but also in household reverse osmosis water purifiers, as well as most ultrafiltration, ceramic, KDF, UV and other water purifiers.

 Activated carbon and KDF can remove residual chlorine in water, but the reaction of KDF and chlorine to generate zinc ions (Zn2+) may cause excessive zinc in water. However, using activated carbon to remove chlorine does not have such concerns.

 Activated carbon forms a large number of fine pores of various shapes during the activation process, forming a huge surface area with adsorption effect. Its specific surface area is 500-1200m2/g. The larger the specific surface area, the better the adsorption effect.

 2. Negative effects of activated carbon

 (1) Activated carbon adsorbs a large amount of organic matter. These organic matter will become the nutrition of bacteria and other microorganisms. The bacteria will multiply and proliferate in the micropores of activated carbon, and may cause the total number of colonies in the effluent to exceed the standard.

 (2) The activated carbon in the water purifier converts the ammonia nitrogen in the water into nitrite nitrogen under the catalysis of microorganisms, and the nitrite in the effluent water of the water purifier is often many times higher than the influent water. Nitrite itself is not a carcinogen, but it reacts with amines in water to produce nitrosamines that are strong carcinogens.

 (3) Adding bromine resin (brominated polystyrene hydantoin) to the effluent filtered by activated carbon adsorption or UV sterilization is a good way to solve the problem of excessive microorganisms in the water. chengde wanyang activated carbon factory  Hong Kong Yineng International Co., Ltd. adds a small amount of bromine resin to the post activated carbon filter element of some household reverse osmosis water purifiers, and the water is sterile. It is very popular for export to European countries.

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What are the benefits of the chemical and physical properties of nutshell activated carbon

Activated carbon is something we often hear in our lives. What is activated carbon? bulk activated charcoal pellets  Activated carbon is a kind of carbon that has been treated to make it extremely porous, so it has a very large surface area and can be used for adsorption and chemical reactions. It usually comes from charcoal.

 Physically, activated carbon is combined with the material through van der Waals force or London dispersion force.

 Activated carbon does not combine well with certain chemicals, including alcohols, alcohols, ammonia, strong acids and alkalis, metals, and most inorganic substances such as lithium, sodium, iron, lead, arsenic, fluorine and boric acid.

 Activated carbon can indeed absorb iodine very well. activated coconut charcoal powder  In fact, the iodine value mg/g (ASTM D28 standard method test) is used as an indicator of the total surface area.

 Activated carbon can be used as a substrate of various chemical substances to improve its ability to adsorb certain inorganic (and organic) compounds, such as hydrogen sulfide (H2S), ammonia (NH3), formaldehyde (HCOH), mercury (Hg) and radioisotope iodine -131 (131I). This property is called chemical adsorption.

 Activated carbon can be used as a substrate of various chemical substances to improve its ability to adsorb certain inorganic (and organic) compounds, such as hydrogen sulfide (H2S), ammonia (NH3), formaldehyde (HCOH), mercury (Hg) and radioisotope iodine -131 (131I). This property is called chemical adsorption.

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How to improve the effect of polyacrylamide

As the main sewage treatment agent at present, polyacrylamide PAM is widely used in the purification of urban sewage and factory sewage, which is inseparable from its good flocculation effect. There are also certain differences in the flocculation effect of polyacrylamide PAM in different usage methods.

 1. Before, several small experiments were used to determine the specific use and concentration of the polyacrylamide PAM model. anionic polyacrylamide suppliers  Personnel handling polyacrylamide should wear protective equipment to avoid solutions. Connect to the body.

 2. Slide the polyacrylamide solution into the mixing tank when the temperature is lower than 60°C, and control the stirring speed between 100-250°C.

 3. Through this test, we can basically determine the pH value and dosage of PAM polyacrylamide.

 4. According to the PH and usage, choose to add the correct configuration solution and stir quickly to avoid condensation at a certain time and speed.

 5. According to this method, PAM polyacrylamide solution can be used directly. It is recommended to use it immediately. wholesale polyacrylamide  Don't wait until the next day. Thank you.

 6. The experiment has not been completed yet, and cleaning agents are needed to avoid accidents.

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Performance comparison between white corundum and black corundum

Many people may know the performance of white fused alumina. As for the performance of black fused alumina, some friends know about it. silicon carbide manufacturers usa  Some friends must be wondering why the performance of white fused alumina should be compared with that of black fused alumina. The difference and role of the person. 　　

 The performance of white corundum can be summarized in the most straightforward and simple language: high hardness, good flexibility, wear resistance, corrosion resistance and good stability. It is suitable for grinding different steel materials and processing various abrasive tools.

 White corundum can be divided into two densities, 1. bulk density and 2. vacuum density.

 The addition of white corundum can make advanced refractory materials. After careful smelting, black corundum has good quality, small particle size, high density, moderate hardness, good flexibility and high purity. abrasives china manufacturers  Suitable for surface polishing of pavement, runway, special construction and abrasive tools, steel, wood and glass. The production of sandpaper is also commonly used.

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How about desulfurization columnar activated carbon?

As a solid adsorbent, activated carbon is widely used in various places. Especially in gas-phase and liquid-phase treatment, it is often used in the treatment of waste gas and wastewater, and industrial desulfurization activated carbon plays a very important role. Desulfurization columnar activated carbon has won consumers’ attention with its unique advantages. Favor. So, what are its outstanding advantages?

 The hydrogen sulfide contained in industrial waste gas is a harmful gas, and its direct emission will seriously affect the air quality in the entire area. coconut shell activated carbon price per ton  The desulfurization columnar activated carbon is mainly used to treat hydrogen sulfide in the waste gas and convert it into captureable by chemical methods. The solid sulfide is further removed.

 Hydrogen sulfide will react under the action of oxygen, and the produced elemental sulfur will be deposited in the micropores of activated carbon, as will part of the solid sulfide produced. Through this principle, the desulfurization process can be completed only by using activated carbon as the medium for this reaction, and through the correct recovery method.

 Of course, the desorption effect is directly dependent on the quality of the activated carbon medium. Due to the strong gas flow, if the adsorption speed and adsorption capacity of activated carbon cannot reach the same height, exhaust gas will still escape.

 It is worth mentioning that when the activated carbon is made into a column, it has a better effect in exhaust gas treatment. yongruida carbon pellets  Compared with our common powder or spherical activated carbon, the column has a more standard shape and can be combined into a suitable one through different stacking methods. In addition, the columnar activated carbon material will not cause accidents such as clogging. Users can make the exhaust gas smooth through a specific combination, and extend the circulation time to improve the adsorption effect.

 There are many types of desulfurization activated carbon, similar to water purification carbon, including honeycomb activated carbon, coconut shell activated carbon, columnar activated carbon, nut shell activated carbon and so on.

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How often should activated carbon be replaced?

Activated carbon refers to a black porous solid substance, its main component is carbon, its main function is adsorption, and it is often used as an industrial adsorbent. It can effectively adsorb carbamate pesticides, organic phosphorus, and chlorinated water in water. Hydrocarbons and other esters and aromatic compounds. This is the adsorption process. activated charcoal nz wholesale This link is carried out on the pores and surface of activated carbon. After adsorption, these substances aggregate on the surface and pores of activated carbon. The pores and surface area of ​​activated carbon are Limited, so when the activated carbon reaches the upper limit of adsorption, we have to replace the activated carbon in time. So how often should activated carbon be replaced?

 Regarding how often activated carbon should be replaced, it is necessary to know in which aspect the activated carbon is used, and cannot be generalized. If activated carbon is used to treat water, we must consider the quality of the water, the amount of activated carbon put in the water, and the adsorption capacity of the activated carbon, and then according to the surface adsorption material of the activated carbon put into the water for the first time The quantity is used to determine how often the activated carbon should be replaced. Generally speaking, the activated carbon for water treatment should be replaced once a year.

 If it is to treat exhaust gas, we also need to consider the amount of substances contained in the exhaust gas, and then consider the quality and adsorption capacity of the activated carbon, and then put the activated carbon in the water, regularly observe the adsorption of substances on the surface of the activated carbon, and then determine the activated carbon used to treat the exhaust How often is it replaced? activated carbon price  Generally speaking, the activated carbon for waste gas treatment should be replaced every three months or so, because the pollution of the waste gas is more complicated.

 The replacement cycle of each type of activated carbon is different. The replacement cycle of honeycomb activated carbon is 12-40 weeks, the replacement cycle of cylindrical activated carbon is 15-30 weeks, and the replacement cycle of coconut shell activated carbon and nutshell activated carbon is 30-60 weeks. The replacement cycle of activated carbon is 2-20 weeks.

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Introduction to the types of polishing materials

Artificial emery-with high hardness and low toughness (compared to other abrasives) is mainly used for rough grinding and polishing of low-strength metals (such as pig iron, brass, bronze, etc.).

Corundum-There are two kinds of artificial and natural. The more bauxite Al2O3 content in corundum, the higher its hardness. Corundum is a better material for rough grinding with a grinding wheel. fused alumina manufacturer in india  It has greater toughness than artificial emery. The particles of corundum are multi-faceted, and the sharp edges of the particles are blunt than those of artificial emery. It is suitable for polishing tougher metals with greater breaking strength, such as quenched steel, malleable cast iron, manganese bronze, etc.

Emery-has medium hardness and excellent toughness, suitable for polishing all metals.

Diatomaceous earth-has a not-so-sharp cutting surface and excellent toughness, which can smooth out scratches and scratches on the metal surface. It is a universal polishing and polishing material.

Quartz sand-particles with medium hardness, it has no sharp cutting surface, and its toughness is also very good. hsl abrasive refractory factory  It is a general-purpose polishing and polishing material.

Pumice-It has poor hardness and is relatively crisp, suitable for grinding and polishing wood, leather, rubber, plastic and glass.

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What is the function of the unshaped granular activated carbon from the shell?

Unshaped granular activated carbon from husk is made of peach husk, apricot husk, squash husk, walnut husk, coconut husk and other husks as raw materials. It is refined through a series of production processes. activated carbon pellets aquarium  The appearance is black and granular, with developed voids and adsorption It has the advantages of good performance, economy and durability. It is mainly used for the purification, purification and decolorization of power plant boiler water, industrial water, domestic water, beverage water and other various industrial wastewater.

 Formaldehyde in household life, building materials, interior decoration materials, furniture and smoking, cooking oil fume, fuel burning, etc. are the sources of indoor formaldehyde pollution. Research shows that formaldehyde has carcinogenic and cancer-promoting effects.

 The impact of formaldehyde on human health is first manifested in the abnormal sense of smell, irritation, allergies, abnormal lung function, abnormal liver function and abnormal immune function. Exposure to formaldehyde in the air and many other similar indoor polluted air will cause symptoms of clear eyes, tingling nose and throat.https://coconutactivatedcarbon.com

 The adsorption properties of the unshaped granular activated carbon from the husk include "physical adsorption" and "chemical adsorption", which can adsorb certain organic compounds. According to this adsorption principle, the non-shaped granular activated carbon from the shell can effectively remove the formaldehyde and other pollutants after the decoration of the new house.

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Do you know what is wooden columnar activated carbon

1. Wooden columnar activated carbon is made of fine sawdust, coconut shell, apricot shell, etc. as raw materials through a series of production processes such as crushing, extrusion, mixing, molding, drying, carbonization, and activation.

 2. The wooden columnar activated carbon has changed the traditional method of forming with coal tar, starch and other traditional binders. activated carbon bulk australia  It relies on the affinity between carbon molecules and the special properties of the raw material itself, and does not contain binder components.

 The wooden columnar activated carbon produced by this method can effectively avoid the clogging of the carbon pores, and can also give full play to the rich and developed carbon pore adsorption function.

 3. Wooden columnar activated carbon uses fine wood chips and coconut shell as raw materials. Compared with traditional coal columnar activated carbon, the columnar activated carbon has lower ash content, less impurities, gas phase adsorption value, and CTC is dominant. yongruida active carbon  The product has a reasonable pore size distribution and achieves greater adsorption And desorption, thus greatly improving the service life of the product (average 2-3 years), which is 1.4 times that of ordinary coal-based columnar activated carbon.

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The difference between calcined and fused white corundum

Fused white corundum is a white frit made of industrial alumina powder as raw material, cooled and recrystallized after being smelted at a high temperature of over 2000 degrees. aluminium oxide powder The main chemical composition is Al2O3 with a content of over 99% and little impurity. The smelting process of white fused alumina is basically the same as that of brown fused alumina, and it is divided into four stages: furnace opening, smelting, control, and refining.

 Fused white corundum is suitable for manufacturing ceramics, resin-consolidated abrasive tools, as well as grinding, grinding wheels, polishing, sandblasting, precision casting (corundum for precision casting), etc. If sandblasted, it is relatively sharp, uniform in particle size, and free of dust. Its smelting process is similar to that of brown corundum, which is divided into dumping method, frit method and exile method. Generally, the smelting method of brown corundum is relatively simple.

 The Al2O3 of fused white corundum>99%, the block is pure white, the apparent porosity is 6%-10%, the main crystal phase is a-Al2O3, the crystals are elongated and rhombic, and they are often skeletal crystals. As the raw material for smelting white corundum, calcined alumina or industrial alumina is very pure, no chemical reaction occurs in the electric melting operation, but the temperature and cooling rate of the molten liquid have a great influence on the structure of the block.

 In terms of homogeneity, it is important to obtain as dense a block as possible. When the Na2O in the raw material solidifies, β-Al2O3 is formed, which tends to be concentrated in the center of the block, which will adversely affect the refractory and abrasive materials. hsl abrasive factory Therefore, attention must be paid to the content of Na2O3 in the raw material. In addition, there is still a small amount of nepheline and glass in the block.

 Sintered white corundum is calcined at a temperature above 1800°C, and the crystal size grows from 10 microns to more than 100 microns, forming dense sintering between crystals. It has the characteristics of high purity of Al2O3, reaching 99.5%—99.6% or more, and less impurities, especially less Na2o.

 Compared with fused white corundum, the obvious difference in structure is the crystal size and the state of pores. The fused white corundum has more large pores, but the shape is variable, and there are more open pores; the total pores of sintered white corundum are not much larger than that of fused However, most of them are in the form of closed stomata and are spherically divided in the particles, and some are concentrated in the grain boundaries. The more developed the crystal, the larger the pores.

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Modification of activated carbon's physical and structural properties

The appearance characteristics of activated carbon are composed of these aspects, such as the specific surface area, the volume of the micropores, and the structure.These characteristics are inseparable from the adsorption function of activated carbon.The progress of these elements can greatly improve its adsorption.

 The improvement of activated carbon, that is, the use of some chemical methods to modify the specific surface area and pore structure of the activated carbon data, and the improvement of the pores can allow the activated carbon to absorb more molecular-level pollutants. The heat shrink method and gas phase pyrolysis of the pores are carried out, which can reduce the pore size of the activated carbon.https://www.powdered-activated-carbon.com/

 In the production process of activated carbon, many factors will affect the final function, such as the temperature, time, type of activator, etc., changing any of the factors in the process can make the final adsorption function very different.

 1. Modification of chemical properties

 The surface chemical properties of activated carbon are determined by chemical functional groups, external heteroatoms and oxides. These elements are the same as the production process of the activity and will also affect the final adsorption function. Different chemical functional groups are also different in the adsorbed substances. The same, for example, basic oxygen-containing functional groups, compared to simple adsorption of substances with weaker polarity.

 Modifying the chemical properties of activated carbon, that is, changing its functional groups, can make activated carbon more hydrophilic or more hydrophobic, and can also improve the adsorption function of heavy metals. In the process of improvement, the surface oxidation of activated carbon can be modified. It can also modify its acidity and alkalinity, etc.In the process of modification, it is usually connected in different ways, so that it can have a very good effect. activated-carbon-pellets.com

 2. Modification of electrochemical properties

 The constituent elements of activated carbon determine that it has a certain conductive function, can capture some charges, and modify the electrochemical properties of activated carbon, that is, to use certain methods to modify the conductive function of activated carbon, so that its adsorption has a certain choice Sex.

 After changing the electrochemical properties of activated carbon, change the adsorption function, such as the adsorption of chloroform in water.If the potential of activated carbon increases, then the adsorption will accelerate.If the potential decreases, on the contrary, it will reduce the adsorption of chloroform.

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Application of powdered activated carbon in printing industry

Powdered activated carbon is made from wood chips through a special production process. The process flow of powdered activated carbon is as follows: screening and drying of sawdust, ingredients and impregnation, loading into furnace for activation, recycling, rinsing, centrifugal dewatering, drying and grinding, and entering the packaging process and warehouse storage.

In recent years, printing and dyeing wastewater has been plagued by the printing and dyeing industry, so many manufacturers have been very active in the research on the decolorization of printing and dyeing wastewater. activated activated pellets wholesale According to the different treatment methods, they are generally divided into two types of treatment methods, biochemical and physical and chemical methods. The method includes adsorption, coagulation, neutralization and other methods, while the biochemical method includes activated sludge method, biological turntable and other methods, but the process used in water treatment is generally a combination of multiple methods, which can play Special effect.

 The adsorption method usually uses powdered activated carbon. Powdered activated carbon is selective for dyes. yongruida  It is composed of a variety of pores. Through the pores, the printing and dyeing wastewater can pass through a filter bed composed of granular materials. The material surface is removed by adsorption and decolorization.

The use of powdered activated carbon can effectively remove reactive dyes, basic dyes, and azo dyes in wastewater. Of course, under certain conditions, it can also directly adsorb certain heavy metal ions. Therefore, powdered activated carbon is a very good material in the printing and dyeing industry. Good decolorizing product.

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What is activated carbon filter

The activated carbon particle filter is filled in a plastic filter housing without any chemical additives. wanyang honeycomb carbon There are multiple layers of microfiber non-woven fabrics at the upper and lower inlets and outlets of the container to prevent the release of carbon powder. The outer shell is made of ABS material by ultrasonic welding.

 Since the liquid flows from the bottom to the top, the liquid is in contact with the activated carbon particle layer for a long time and in a large area, so the functions of dechlorination, deodorization and deodorization can be effectively used.

 The activated carbon filter core is filled with the required activated carbon particles into a special plastic shell, and the end caps at both ends of the shell are welded with welding equipment. wanyang activated charcoal  The two ends of the shell are put into the non-woven filter respectively, and the non-woven filter plays a filtering role to ensure that the carbon core in use will not fall off from the carbon powder and black water. According to needs, the shell end cover can be made into different types of connectors. Interface methods are: flat pressure type and pipeline type.

 Coal-based activated carbon mostly uses coal and tar as raw materials and is made by a special process. It has the advantages of developed pores, large surface area, and high mechanical strength. It is widely used in toxic gas review, waste gas treatment, industrial and domestic water purification.

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What is the continuous operation of activated carbon

Since the regeneration problem of used powdered activated carbon was solved, some larger-scale applications have also selected powdered carbon. Continuous operation is often used for larger scale use of granular activated carbon.

 Continuous operation is often used for larger-scale production using granular activated carbon. The equipment includes:

 1. A fixed bed is a method in which activated carbon is used as a packed layer, and fluid flows continuously from above or below for adsorption, because the activated carbon in this equipment is fixed during operation. how to make activated charcoal pellets  The fixed bed has a single bed, multiple beds in series and multiple beds in parallel according to fluid volume and processing requirements.

 2. Moving bed refers to the intermittent mobile adsorption mode of activated carbon. The fluid to be treated flows in from the bottom of the adsorption tower, contacts the activated carbon countercurrently, and the treated fluid flows out from the top of the tower.

 3. Fluidized bed, which is a continuous fluidized bed adsorption method, which decolorizes sugar early. Activated carbon forms an expanded layer or fluidized state in the tower, and has more contact with the fluid entering from the bottom of the tower, and then is continuously discharged outside the tower. coconut shell based steam activated carbon  If the fluid flow rate is too large, the expansion rate of the activated carbon in the tower will increase, and the layered movement cannot be maintained, so the flow must be strictly adjusted.