CN115337918A - Activated carbon regeneration system and method - Google Patents

Abstract

The invention discloses an active carbon regeneration system and method, wherein the system comprises: the system comprises a raw material pretreatment and feeding system, a vertical multi-stage regenerative furnace and a waste heat recovery system which are sequentially connected; the raw material pretreatment and feeding system comprises a drying furnace, and the vertical multi-section regeneration furnace comprises a distributor, a carbonization bin, an activation bin and a regenerated carbon cooler in an up-down arrangement sequence. The activated carbon regeneration method comprises the following steps: preliminarily drying the activated carbon to be activated; activating the preliminarily dried activated carbon to be activated to obtain activated carbon and activated tail gas, and generating combustion flue gas; respectively recovering the activated tail gas and heat generated by the activated tail gas, wherein the recovered activated tail gas is used as fuel gas after being dedusted, and the recovered heat is used for heating desalted water to generate steam which is respectively used as cloth steam and activated steam; and (3) using the combustion flue gas as a heat source for primarily drying the activated carbon to be activated, performing environment-friendly treatment on the cooling flue gas, and then discharging the cooled flue gas, and repeating the steps until the activated carbon to be activated is treated.

Description

A kind of activated carbon regeneration system and method

technical field

The invention relates to the technical field of activated carbon regeneration, in particular to an activated carbon regeneration system and method.

Background technique

Activated carbon has a highly developed pore structure and high specific surface area, stable chemical properties, and strong adsorption capacity for organic substances. As an excellent adsorbent, it is widely used in medicine, metallurgy, food, chemical industry, military and environmental protection, etc. each field. However, on the one hand, activated carbon production resources are becoming more and more scarce, and the price is high; on the other hand, it is difficult to regenerate activated carbon after adsorption and saturation. The general activated carbon regeneration method is often complicated due to regeneration operations and high regeneration costs, resulting in a large amount of waste activated carbon. Incineration, Landfilling and other methods will cause waste of resources and environmental hazards. Therefore, from the perspective of economy and environmental protection, the regeneration of activated carbon is of great significance.

At present, the technologies for regeneration of activated carbon mainly include: chemical agent regeneration method, thermal regeneration method, biological regeneration method, electrochemical regeneration method and so on. Among them, thermal regeneration is the most common application, and this method is suitable for almost all saturated activated carbons whose adsorbate is organic matter. However, the current thermal regeneration method generally has the problems of high regeneration cost, low thermal efficiency, and large pollutant discharge, and the yield of regenerated activated carbon is relatively low. For example, a vertical fluidized furnace is used to regenerate powdered activated carbon. The equipment structure is relatively simple and continuous production is carried out. However, the high-temperature exhaust gas is cooled by spraying water, and the burned carbon powder is collected by a bag filter, or directly collected by a wet filter. The obtained product is in the form of Slurry, thermal energy is not fully utilized. Other main regeneration methods such as smoldering furnace method, flat furnace method, groove furnace method, molding granulation activation method (vertical furnace), these methods are all implemented intermittent production, high energy consumption, low yield, environmental pollution and product quality Poor, labor-intensive.

Contents of the invention

In view of this, the present invention aims at the problems existing in activated carbon regeneration technology, and provides an activated carbon regeneration system and method, which has the advantages of high production efficiency, low energy consumption, continuous production, stable performance of regenerated activated carbon, high yield, no pollution and Low labor intensity and other advantages. Technical scheme of the present invention is:

In the first aspect, the present invention provides an activated carbon regeneration system, including: sequentially connected raw material pretreatment and feeding system, vertical multi-stage regeneration furnace and waste heat recovery system;

The raw material pretreatment and feeding system includes a drying furnace, the hot flue gas inlet of the drying furnace is connected with the flue gas main pipe of the combustion heating mechanism of the vertical multi-stage regeneration furnace; the air inlet of the drying furnace is connected with the hot blast furnace The air outlet is connected, the air inlet of the hot blast stove is connected with the exhaust dust collector outlet of the waste heat recovery system; the discharge port of the drying furnace is connected with the inlet of the dry charcoal silo, and the outlet of the dry charcoal silo is connected with the The feed port of the vertical multi-stage regeneration furnace; the exhaust gas outlet of the drying furnace is connected to the flue gas purification device;

The vertical multi-stage regenerating furnace includes a furnace body, and the furnace body includes a distributor, a carbonization bin, an activation bin and a regenerated carbon cooler in the order of arrangement up and down, and the distributor is connected to the feed port of the furnace body, so The distributor is provided with a distributor steam inlet; between the carbonization bin and the activation bin or in the activation bin is provided with at least one tail gas outlet, and the tail gas outlet is connected to the tail gas cooler of the waste heat recovery system to enter Gas port; the activation chamber is provided with an activation chamber steam inlet; the carbonization chamber and the activation chamber are respectively provided with at least one combustion heating mechanism; the regenerated carbon cooler and the discharge of the furnace body The steam inlet of the distributor and the steam inlet of the activation chamber are both connected with the heat exchange fluid outlet of the tail gas cooler of the waste heat recovery system.

Further, each of the combustion heating mechanisms includes two burners, the two burners are connected through a connecting body, and a heat transfer element is arranged in the connecting body, and the burners are installed outside the furnace body, so The connecting body is located inside the furnace body; the two burners are respectively connected to the flue gas main pipe, gas main pipe and compressed air main pipe through three three-way valves, and the flue gas main pipe is also connected to the hot flue gas of the drying furnace The gas main pipe is also connected to the outlet of the exhaust dust collector of the waste heat recovery system, and the compressed air main pipe is also connected to the compressed air pump.

Preferably, the connecting body is made of heat-resistant alloy steel.

Optionally, the connecting body may be arranged in parallel and/or vertically with the furnace body.

Further, the heat transfer element is filled with several porous ceramic regenerators.

Further, the waste heat recovery system includes an exhaust gas cooler, an exhaust gas dust collector, a sub-steam drum and a dust collection tank, the outlet of the exhaust gas cooler is connected to the inlet of the exhaust gas dust collector, and the exhaust gas dust collector The dust outlet of the dust collector is connected to the dust collection tank, and the gas outlet of the tail gas dust collector is connected to the gas main pipe of the combustion heating mechanism and the air inlet of the hot blast stove respectively; the steam outlet of the sub-steam drum is respectively connected to the The steam inlet of the activation chamber is connected to the steam inlet of the distributor, the liquid inlet of the sub-steam drum is connected to the desalted water pipeline, the liquid outlet of the sub-steam drum is connected to the inlet of the desalted water circulating pump, and the desalted water circulating pump The outlet is connected to the circulating liquid inlet of the regenerated carbon cooler, the circulating liquid outlet of the regenerated carbon cooler is connected to the heat exchange liquid inlet of the heat exchanger, and the heat exchange liquid outlet of the heat exchanger is connected to The soda water inlet of the sub-steam drum.

Preferably, the hot blast stove is also equipped with a combustion-supporting fan, which is connected to the combustion-supporting air inlet of the hot-blast stove to provide combustion-supporting air for the hot blast stove.

In a second aspect, the present invention provides a method for regenerating activated carbon, comprising:

The activated carbon to be activated is initially dried in a drying oven;

The preliminarily dried activated carbon to be activated is introduced into a vertical multi-stage regeneration furnace for activation to obtain activated activated carbon and activated tail gas, and generate combustion flue gas;

The activated tail gas and the heat generated are recovered separately through the waste heat recovery system. Among them, the recovered activated tail gas is used as fuel gas after dedusting, and the recovered heat is used to heat desalted water to generate steam, which is used as cloth steam and activation steam respectively;

The combustion flue gas is used as a heat source for preliminary drying of the activated carbon to be activated, and the cooled flue gas is discharged after environmental protection treatment, and so on, until the activated carbon is treated.

Further, the activated carbon to be activated is preliminarily dried in a drying oven, and the temperature of the drying oven is controlled at 130°C-200°C, preferably at 150-190°C; the moisture content of the dry carbon is 5%-15%, preferably At 5%-10%.

Further, the control parameters for activating the preliminarily dried activated carbon to be activated are: the pressure in the hearth of the vertical multi-stage regeneration furnace is -0.01MPaG-0.2MPaG, preferably -0.01MPaG-0.1MPaG; the temperature of the carbonization bin is controlled at 440 °C-600 °C, preferably 500-550 °C, the temperature of the activation chamber is controlled at 600 °C-1100 °C, preferably 700-900 °C.

Further, the preliminarily dried activated carbon to be activated is introduced into a vertical multi-stage regeneration furnace for activation, and part of the steam participating in the activation reaction is cloth steam and a part is activation steam.

Further, in the process of introducing the preliminarily dried active carbon to be activated into the vertical multi-stage regeneration furnace for activation, the total consumption Q of the distribution steam and the activation steam is calculated according to the following formula:

Q=W(Fc×η-, Q: total steam flow, Kg/h; W: dry charcoal flow, Kg/h; Fc: fixed carbon content of dry charcoal, %; η: steam coefficient, 10% to 15% ; M: total water content of dry charcoal, %; wherein, the cloth steam accounts for 20%-50% of the total steam.

Further, the dust content of the activated exhaust gas is controlled to be <5mg/m ³ . Compared with prior art, the present invention can obtain and comprise following technical effect:

(1) The present invention is applicable to all media from powder activated carbon to granular activated carbon, and regeneration of waste activated carbon of various specifications from biomass activated carbon to coal-based activated carbon. The yield of regenerated carbon can reach 50%-95%. The performance reaches 92%-130% of the new carbon.

(2) The present invention utilizes raw material pretreatment and feeding system, vertical multi-stage regenerating furnace and waste heat recovery system to circulate and cooperate, and the high-temperature charcoal after the activation reaction and high-temperature tail gas waste heat recovery production steam are used as activators, and the waste heat recovered After the activation tail gas is deeply filtered and purified, it returns to the regeneration furnace to burn to maintain the temperature required for activation, and the flue gas after the activation tail gas is used to dry the raw material of wet waste activated carbon. The heat required for activation can basically reach self-balance, which has production efficiency. High, low energy consumption, continuous production, stable performance of regenerated activated carbon, high yield, no pollution and low labor intensity.

Description of drawings

The drawings described here are used to provide a further understanding of the application and constitute a part of the application. The schematic embodiments and descriptions of the application are used to explain the application and do not constitute an improper limitation to the application. In the attached picture:

Fig. 1 is the structural representation of activated carbon regeneration system of the present invention.

Fig. 2 is a structural schematic diagram of the combustion heating mechanism of the activated carbon regeneration system of the present invention.

Fig. 3 is the iodine value of the new carbon and the iodine value change of the regenerated carbon in Example 2 of the present invention.

Fig. 4 is the variation of the regenerated carbon yield relative to each regeneration in Example 2 of the present invention.

Fig. 5 is the change curve of the regeneration rate of the wet oxidation method in comparative example 2 of the present invention.

In Figures 1 and 2, 1 raw material pretreatment and feeding system, 101 drying furnace, 102 drying furnace tail gas fan, 103 dry charcoal conveying mechanism, 104 dry charcoal silo, 105 feeder; 2 vertical multi-stage regeneration furnace, 201 Distributor, 202 carbonization bin, 203 activation bin, 204 tail gas outlet, 206 combustion heating mechanism, 207 burner, 208 connector, 209 porous ceramic regenerator, 210 flue gas pipe, 211 flue gas three-way valve, 212 flue gas Main pipe, 213 gas pipe, 214 gas three-way control valve, 215 gas main pipe, 216 compressed air pipe, 217 compressed air three-way control valve, 218 compressed air main pipe, 219 furnace body; 3 waste heat recovery system, 301 tail gas cooler, 302 Exhaust gas dust collector, 303 dust collection tank, 304 regenerated carbon cooler, 305 steam drum, 306 forced circulation pump, 307 hot blast stove, 308 cloth steam pipe, 309 activated steam pipe, 310 hot blast stove fan, 4 regenerated carbon silo, A supplementary gas, B waste activated carbon, C compressed air, D steam main, E desalted water, F supplementary gas.

Detailed ways

In the description of the present invention, the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "parallel", "top", " The orientation or positional relationship indicated by "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and does not require that the present invention must be constructed and operated in a specific orientation, Therefore, it should not be construed as limiting the invention.

In the description of the present invention, it should be noted that those in the examples that do not specify specific conditions shall be carried out according to conventional conditions or conditions suggested by the manufacturer. The reagents or instruments used were not indicated by the manufacturer, and they were all conventional products that could be purchased from the market.

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments, which are explanations rather than limitations of the present invention.

As shown in Figures 1 and 2, the specific embodiment of the present invention provides an activated carbon regeneration system, including: a raw material pretreatment and feeding system 1 connected in sequence, a vertical multi-stage regeneration furnace 2 and a waste heat recovery system 3 .

The raw material pretreatment and feeding system 1 includes a drying furnace 101 , a dry charcoal conveying mechanism 103 , and a dry charcoal hopper 104 . The drying furnace 101 uses waste heat of the flue gas to heat and dry the activated carbon to be activated. The drying furnace 101 can be a boiling drying furnace or a rotary drying furnace. The air inlet of the drying furnace 101 is connected to the flue gas main pipe 212 of the combustion heating mechanism 206 of the vertical multi-stage regeneration furnace 2; The outlet is connected to the dry carbon storage bin 104, and the dry carbon storage bin 104 is connected to the feeder 105 of the vertical multi-stage regeneration furnace 2, and the feeder 105 outlet is connected to the inlet of the vertical multi-stage regeneration furnace 2. feed port. The air inlet of the drying furnace 101 is connected with the air outlet of the hot blast stove 307 . The drying furnace 101 is equipped with a drying furnace tail gas fan 102, which is connected to a flue gas purification device for purification and then discharged. The drying furnace tail gas purification adopts conventional flue gas desulfurization and dust removal technology.

The vertical multi-stage regenerative furnace 2 includes a furnace body 219. The furnace body 219 includes a distributor 201, a carbonization bin 202, an activation bin 203 and a regenerated carbon cooler 304 in the order of setting up and down. The distributor 201 is connected to the feed port of the furnace body 219. The distributor 201 is provided with a distributor steam inlet; the activation chamber 203 is provided with a tail gas outlet 204, and the tail gas outlet 204 is connected to the exhaust gas cooler 301 air inlet of the waste heat recovery system 3; the activation chamber 203 is provided with an activation chamber steam import. The carbonization chamber 202 and the activation chamber 203 are respectively equipped with a combustion heating mechanism 206. The combustion heating mechanism 206 includes two burners 207, and the two burners 207 are connected by a connecting body 208. The material of the connecting body 208 is at least 1200 ° C. Heat-resistant alloy steel for work. The connecting body 208 is provided with a heat transfer element. The heat transfer element is composed of a plurality of refractory porous ceramic regenerators 209 filled sequentially. The porous ceramic regenerator has a certain porosity inside and can circulate high-temperature flue gas. The burner 207 is installed outside the furnace body 219, and the connecting body 208 is located inside the furnace body 219; the two burners 207 are respectively connected to the flue gas main pipe 212, the gas main pipe 215 and the compressed air through three three-way valves (211, 214, 217). Manager 218. The flue gas main pipe 212 is also connected to the hot flue gas inlet of the drying furnace, and the hot flue gas generated by the burner is used to dry the activated carbon to be activated. The gas main pipe 215 is also connected to the gas outlet of the tail gas dust collector 302 of the waste heat recovery system 3, and the tail gas generated by the waste heat recovery system is used as part of the gas. The compressed air main pipe 218 is also connected with a compressed air pump. In this embodiment, the combustion heating mechanism 206 is vertically arranged with the furnace body 219 . In addition, multiple combustion heating mechanisms 206 can also be provided according to the specifications of the vertical multi-stage regeneration furnace 2 . The regenerated carbon cooler 304 is connected to the discharge port of the furnace body 219 , and the discharge port of the furnace body 219 is connected to the regenerated carbon storage bin 4 .

The waste heat recovery system 3 includes an exhaust gas cooler 301, an exhaust gas dust collector 302, a sub-steam drum 305 and a dust collection tank 303. Connect with the feed port of the dust collection tank 303, the gas outlet of the exhaust gas dust collector 302 is connected with the gas main pipe 215 of the combustion heating mechanism 206, the gas outlet of the tail gas dust collector 302 is also connected with the air inlet of the hot blast stove 307, and the gas outlet of the hot blast stove 307 The air outlet is connected to the air inlet of the drying furnace 101, and the hot blast stove 307 is also equipped with a combustion-supporting blower 310. The combustion-supporting blower 310 is connected to the combustion-supporting air inlet of the hot blast stove 307 to provide combustion-supporting air for the hot blast stove. The steam outlet of the sub-steam drum 305 is connected to the steam inlet of the activation chamber 203 and the steam inlet of the distributor 201 respectively, the liquid inlet of the sub-steam drum 305 is connected to the desalinated water pipeline, and the other end of the desalted water pipeline is connected to the desalinated water device. The preparation of desalted water It is a conventional means in the art, and will not be explained in detail here. The liquid outlet of the sub-drum 305 is connected to the circulating liquid inlet of the regenerated carbon cooler 304 through the forced circulation pump 306, and the circulating liquid outlet of the regenerated carbon cooler 304 is connected to the heat exchange liquid inlet of the tail gas cooler 301, and the tail gas cooler 301 The outlet of the heat exchange liquid is connected with the steam inlet of the sub-steam drum 305 to form a steam-water cycle. In this embodiment, the outlet steam pipeline at the top of the steam drum 305 is divided into three paths, one path is the distribution steam 308, which is connected to the steam interface of the vertical multi-stage regeneration furnace 2 distributor 201; the other path is the activated steam 309, which is connected to the vertical Type multi-stage regenerating furnace 2 on the furnace body between the outlet above the activation material and below the activation chamber; the third road is to regulate steam, which is connected to the external steam pipe network. There are corresponding steam flow meters and steam flow control valves on the steam pipes.

In the above system, the waste activated carbon is dried in direct contact with the flue gas sent from the vertical multi-stage regeneration furnace in the raw material pretreatment and feeding system, and then enters the vertical multi-stage regeneration furnace and the steam sent from the waste heat recovery system Activation reaction occurs at high temperature to obtain regeneration. On the one hand, the waste heat recovery system dedusts and purifies the high-temperature activated tail gas produced by the vertical multi-stage regeneration furnace and returns it to the combustion heating mechanism of the vertical multi-stage regeneration furnace for combustion, and the flue gas generated by combustion enters the drying furnace to dry the wet waste activated carbon; on the other hand By using the desalinated water heat exchange to recover the high-temperature regenerated carbon waste heat of the vertical multi-stage regeneration furnace and the waste heat of the exhaust gas activated by the vertical multi-stage regeneration furnace to produce steam, the by-produced steam is used for material dispersion and gasification pore formation of the vertical multi-stage regeneration furnace.

The specific embodiment of the present invention also provides a kind of regeneration method of biomass activated carbon powder, is to adopt above-mentioned system, specifically comprises the following steps:

Step 1, start the furnace and heat up: supply gas and compressed air to the combustion heating mechanism 206, ignite the burner 207, gradually heat up the shell connector 208, drive the temperature of the carbonization chamber 202 of the regeneration furnace to rise to 400°C-450°C, and activate the temperature of the chamber 203 When it rises to 750°C-900°C, the flue gas enters the drying furnace 101 through the flue gas three-way valve 211 and the flue gas main pipe 212, and then is drawn out to the flue gas purification device through the drying furnace tail gas fan 102, and the temperature of the drying furnace 101 is preheated to 150°C-200°C; at the same time, replenish water to the 305 steam drum through the desalinated water pipeline, and turn on the forced circulation pump 306 to establish the desalinated water circulation of the waste heat recovery system.

Step 2, drying: feed the material to the drying furnace 101 through the screw feeder, and the flue gas in the furnace blows the waste activated carbon to boil and transfer heat. The temperature in the furnace is controlled at 140°C-220°C. During the residence time, the dried material is discharged from the drying furnace 101 and lifted to the dry charcoal storage bin 104 by the dry charcoal conveying mechanism 103 . The total water content of the dried material is 5%-15%.

Step 3, carbonization and activation: the dry charcoal in the dry charcoal storage bin 104 is sent to the distributor 201 of the vertical multi-stage regeneration furnace through the feeder 105, and the distributor 201 breaks up the powder through the distribution steam to achieve uniform distribution . After the material enters the regeneration furnace, it passes through the carbonization bin 202 and the activation bin 203 from top to bottom, and then enters the regenerated carbon cooler 304 to be cooled and sent to the regenerated carbon bin 4. A part of the steam participating in the activation reaction is the cloth steam from the cloth steam pipe 308, and a part is the activation steam from the activation steam pipe 309. The operating temperature of the carbonization chamber 202 is 440°C-600°C, and the operating temperature of the activation chamber 203 is 600°C-1100°C. The residence time and operating temperature of materials in the furnace are selected according to different material properties, and the residence time of waste charcoal in carbonization bin 202 and activation bin 203 is determined according to the source and nature of waste charcoal.

Step 4, waste heat recovery: the activated tail gas enters the tail gas cooler 301 from the activated tail gas outlet 204 , and after heat exchange with desalted water, the dust is removed by the tail gas dust collector 302 and enters the dust collection tank 303 . At the same time, under the desalinated water circulation, the regenerated carbon heats the desalted water in the regenerated carbon cooler 304 to generate steam, and the desalted water heated by the tail gas cooler 301 and the regenerated carbon cooler 304 enters the sub-steam drum 305 through the forced circulation pump 306 and is separated. Part of the steam after the liquid water goes to the distributor 201 through the distribution steam pipe 308, and part of it passes through the activation steam pipe 309 to deactivate the chamber 203 to participate in the activation reaction, and the excess steam enters the steam main pipe to send out the system. The activated tail gas purified by the activated tail gas dust collector 302 enters the activated tail gas main pipe and is divided into two routes, one of which enters the combustion heating mechanism 206 for use as fuel, and the other enters the 307 hot blast stove for combustion to generate hot air and sends it to the drying furnace 101 for drying. Heat source of wet charcoal.

The iodine value of activated carbon regenerated through the above steps is restored to 950mg/g-1100mg/g, the total water content is less than 2%, the specific surface area is 1100m ² /g-1300m ² /g, and the yield of regenerated carbon can reach 50%- 95%, the performance of regenerated carbon reaches 92%-130% of new carbon.

In step 2, the temperature of the drying furnace is controlled at 130°C-200°C, preferably 150-190°C; the moisture content of the dry charcoal is 5%-15%, preferably 5%-10%.

In step 3, the pressure in the hearth of the vertical multi-stage regeneration furnace 2 is -0.01MPaG-0.2MPaG, preferably -0.01MPaG-0.1MPaG; the temperature of the carbonization chamber of the vertical multi-stage regeneration furnace 2 is controlled at 440°C-600°C , preferably 500-550°C, the temperature of the activation chamber is controlled at 600°C-1100°C, preferably 700-900°C; the residence time of activated carbon in the carbonization chamber is controlled according to different raw material particle sizes and pollutant types, a better control index As shown in Table 1:

Table 1 Typical particle size waste activated carbon regeneration control index

Note: The particle size classification in Table 1 is based on three types of commercially available columnar activated carbon, granular activated carbon and powdered activated carbon.

In step 3, the total consumption Q of the cloth steam and the activation steam is calculated according to the following formula:

Q=W(Fc×η-,

Q: total steam flow, Kg/h;

W: dry carbon flow rate, Kg/h;

Fc: fixed carbon content of dry charcoal, %;

η: steam coefficient, 10% to 15%;

M: total water content of dry charcoal, %;

Wherein, the cloth steam accounts for 20%-50% of the total steam.

In step 4, the temperature of the activated tail gas at the outlet of the tail gas cooler is controlled at 100°C-300°C, preferably 120°C-150°C; the dust content of the activated tail gas at the outlet of the tail gas dust collector is controlled at <5 mg/m ³ ; The operating pressure of drum steam is 0.1MPa-0.3MPa, preferably 0.15MPa-0.2MPa;

Example 1

This embodiment provides a method for regenerating activated carbon. The activated carbon comes from a powdered activated carbon used in the treatment of chemical wastewater. The main performance data of the new carbon are shown in Table 2:

Table 2 Performance analysis data of a new powdered activated carbon for water treatment:

The above-mentioned powdered activated carbon is used for chemical wastewater treatment, and the moisture content of the dehydrated waste carbon after adsorption saturation is about 50%, and the particle size distribution is less than 200 mesh (see Table 3 for the analysis data of its main indicators).

Table 3 water treatment waste activated carbon performance analysis data:

Activated carbon regeneration method specifically comprises the following steps:

Step 1, start the furnace and heat up: supply gas and compressed air to the combustion heating mechanism 206, ignite the burner 207, heat up the shell connector 208 at a rate of 20°C/min, and drive the temperature of the carbonization chamber 202 of the regeneration furnace to rise to 410°C— 450°C, the temperature of the activation chamber 203 rises to 850°C-900°C, the flue gas enters the drying furnace 101 through the flue gas three-way valve 211 and the flue gas main pipe 212, and then is extracted by the drying furnace tail gas fan 102 to the flue gas purification device for drying The temperature of the furnace 101 is preheated to 150°C-200°C; at the same time, the desalinated water pipeline is used to supply water to the 305 steam drum, and the forced circulation pump 306 is turned on to establish the desalinated water circulation of the waste heat recovery system.

Step 2, drying: feed the material to the drying furnace 101 through the screw feeder, and the waste activated carbon is blown by the flue gas in the furnace to boil and transfer heat. The temperature in the furnace is controlled at 150°C-190°C, and the residence time of the activated carbon in the furnace is 25 seconds to 35 seconds, the dried material is discharged from the drying furnace 101 and lifted to the dry charcoal storage bin 104 through the dry charcoal conveying mechanism 103 . The total water content of the dried material is 5%-10%.

Step 3, carbonization and activation: the dry charcoal in the dry charcoal storage bin 104 is sent to the distributor 201 of the vertical multi-stage regeneration furnace through the feeder 105, and the distributor 201 is steamed to break up the powder to achieve uniform distribution. After the material enters the regeneration furnace, it passes through the carbonization bin 202 from top to bottom, the activation bin 203, and then enters the regeneration carbon cooler 304 to be cooled and sent to the regeneration carbon storage bin. Activation steam is passed through the activation steam pipe 309 . The pressure in the hearth of the vertical multi-stage regeneration furnace 2 is 0.05MpaG, the operating temperature of the carbonization bin 202 is 500°C-550°C, and the operating temperature of the activation bin 203 is 770°C-850°C. The residence time of waste charcoal in the carbonization bin 202 is 30 seconds to 50 seconds, and the residence time of waste charcoal in the activation bin 202 is 9 seconds to 20 seconds.

Step 4, waste heat recovery: the activated tail gas enters the tail gas cooler 301 from the activated tail gas outlet 204 , and after heat exchange with desalted water, the dust is removed by the tail gas dust collector 302 and enters the dust collection tank 303 . At the same time, under the work of the desalinated water forced circulation pump 306, the desalinated water enters the regenerated carbon cooler 304 and the tail gas cooler 301 in turn to be heated to generate steam, and the steam and water are mixed into the sub-steam drum 305 to separate the liquid water, and part of the steam passes through the distribution steam pipe 308 Distributor 201, a part of which participates in the activation reaction through the activation steam pipe 309 and the deactivation chamber 203, and the excess steam enters the steam main pipe delivery device. After the activated tail gas purified by the tail gas dust collector 302 enters the activated tail gas main pipe, it is divided into two paths, one path enters the combustion heating mechanism 206 for use as fuel, and the other path enters the hot blast stove 307 to burn to generate hot air and send it to the drying furnace 101 as a drying and humidifying agent. charcoal heat source.

The temperature of the activated tail gas at the outlet of the activated tail gas heat collector is controlled at 130°C-150°C; the dust content of the activated tail gas at the outlet of the activated tail gas dust collector is <5mg/m ³ ; the operating pressure of the sub-drum steam is 0.2MPaG; The total consumption of the distribution steam and the activation steam requires a total steam amount of 25Kg-60Kg per ton of dry charcoal feed, and the distribution steam accounts for 45%-50% of the total steam amount.

The waste activated carbon treated by the above-mentioned regeneration equipment and regeneration method has a yield of regenerated carbon (calculated by fixed carbon) reaching 77%-85%. Its quality index analysis is shown in Table 4.

The performance analysis data of the regenerated activated carbon of table 4 embodiment 1

Example 2

To the waste activated carbon of embodiment 1, according to the regeneration condition of embodiment 1, carry out multiple adsorption-regeneration cycle treatment, after carrying out 5 times of adsorption-regeneration cycle treatment, the regenerated carbon performance, the change situation of regenerated carbon yield are shown in Fig. 1 and Fig. 2.

From the performance of regenerated carbon and the yield data of regenerated carbon after 5 times of adsorption-regeneration cycle treatment, the performance of regenerated carbon after regeneration treatment of waste activated carbon in the present invention is stable, and there will be no obvious reduction in repeated recycling; In terms of yield, it also maintains relative stability, and the loss of each regeneration is about 20%.

Example 3

The present embodiment takes the same regeneration steps as in Embodiment 1, but the regeneration operating conditions are changed as follows, specifically:

Step 3, during carbonization and activation, the operating temperature of the carbonization bin 202 is controlled at 440°C-490°C, and the operating temperature of the activation bin 203 is controlled at 950°C-1100°C. The residence time of waste charcoal in the carbonization bin 202 is 40 seconds to 60 seconds, and the residence time of waste charcoal in the activation bin 202 is 20 seconds to 35 seconds.

The total consumption of the distribution steam and the activation steam requires a total steam amount of 45Kg-73Kg per ton of dry charcoal feed, and the distribution steam accounts for 40%-50% of the total steam amount.

The yield of the activated carbon regenerated under the above conditions reaches 70%-74%. Its quality analysis data are shown in Table 4:

The performance analysis data of the regenerated carbon of table 5 embodiment 2

Since the activation temperature and activation residence time were increased in Example 2, the adsorption capacity of the obtained regenerated carbon was improved, but at the same time the loss rate was also increased, and the yield of regenerated carbon decreased. Therefore, the temperature of the carbonization chamber of the vertical multi-stage regeneration furnace is controlled at 440°C-600°C, preferably 500-550°C, and the temperature of the activation chamber is controlled at 600°C-1100°C, preferably 700-900°C; and the residence time should be moderate.

Example 4

This example provides a method for regeneration of columnar coal-based activated carbon. The raw material comes from tar removal and naphthalene adsorption saturated columnar coal-based activated carbon in the deep purification of coke oven gas. The performance parameters are shown in Table 6.

Table 6 Analysis data of waste columnar coal-based activated carbon with saturated adsorption:

Waste carbon particle size distribution whole water Ash Volatile matter Carbon tetrachloride adsorption rate (%) specific surface area 2mm—4mm ≈32% 1.4% 31.1% 13% 352m²/g

Carry out activation by the method for embodiment 1, concrete process index is as follows:

Step 2, during drying, the temperature of the drying oven is 150° C. to 190° C., and the residence time of the drying oven is 11 minutes to 15 minutes.

Step 3, during carbonization and activation, the operating temperature of the carbonization bin 202 is controlled at 460°C-520°C, and the operating temperature of the activation bin 203 is controlled at 800°C-850°C. The residence time of waste charcoal in the carbonization bin 202 is 20 minutes to 25 minutes, and the residence time of waste charcoal in the activation bin 202 is 20 minutes to 24 minutes.

The yield of activated carbon regenerated under the above conditions reaches 78%-82%. Its quality analysis data are shown in Table 7:

The industrial analysis and elemental analysis data of the regenerated carbon of table 7 embodiment 3

Example 5

This example provides a method for regeneration of granular activated carbon in VOC adsorption treatment. The specific raw material comes from fruit shell granular activated carbon with saturated adsorption in VOC treatment. The performance parameters are shown in Table 8.

The analytical data of the fruit shell granular activated carbon of certain adsorption saturation in table 8:

Waste carbon particle size distribution whole water Ash Volatile matter Carbon tetrachloride adsorption rate (%) specific surface area 10 mesh - 50 mesh ≈9% 1.6% 21.1% 18.6% 413m²/g

Carry out activation by the method for embodiment 1, concrete process index is as follows:

Step 2, during drying, the temperature of the drying oven is 130°C-150°C, and the residence time of the drying oven is 6 minutes-11 minutes.

Step 3, during carbonization and activation, the operating temperature of the carbonization chamber 202 is controlled at 440°C-500°C, and the operating temperature of the activation chamber 203 is controlled at 800°C-850°C. The residence time of waste charcoal in the carbonization bin 202 is 10 minutes to 15 minutes, and the residence time of waste charcoal in the activation bin 202 is 7 minutes to 12 minutes.

The yield of activated carbon regenerated under the above conditions reaches 75%-80%. Its quality analysis data are shown in Table 9:

Industrial analysis and elemental analysis data of the regenerated carbon of table 9 embodiment 4

Comparative example 1

To the waste activated carbon of embodiment 1, adopt the wet regeneration method of Fenton's reagent oxidation, the operating condition of regeneration is as follows:

The molar ratio of H ₂ O ₂ /Fe ²⁺ in Fenton’s reagent is 20:1, the concentration of H ₂ O ₂ is ≈20mmol/L, the regeneration temperature is 60°C, the regeneration time is 1 hour, and the yield of regenerated carbon is over 96%. The performance analysis data of regenerated carbon are shown in Table 10:

The performance analysis data of the regenerated activated carbon of table 10 comparative example 1

dry basis ash Volatile matter on a dry basis Packing density Adsorption value of methylene blue iodine value 1.94% 4.62% 0.53 113mg/g 682mg/g

From the data of regenerated carbon, it can be seen that the loss of fixed carbon regenerated by wet oxidation method is small, and the yield of regenerated carbon is high, but there is the problem of incomplete regeneration, the regeneration time is slightly longer, and the regeneration performance can only recover about 70%.

Comparative example 2

For the waste activated carbon described in embodiment 1, according to the regeneration operation method of comparative example 1, carry out multiple adsorption-regeneration cycle operations, the waste activated carbon is continuously carried out 5 times of adsorption-regeneration cycle treatment, and it is found that the regeneration rate of the regenerated activated carbon increases with the regeneration rate. The number of times increases gradually decreases, and the results are shown in Figure 5. It can be seen that the wet regeneration method cannot completely regenerate the activated carbon. After 5 regeneration cycles, the performance of the regenerated carbon is less than 60% of that of the new carbon.

In summary, the present invention is applicable to all media ranging from powder activated carbon to granular activated carbon, and regeneration of waste activated carbon of various specifications from biomass activated carbon to coal-based activated carbon. The yield of regenerated carbon can reach 50%-95%, and the performance of regenerated carbon is Reach 92%-115% of new carbon.

For example, certain terms are used in the description and claims to refer to specific components or methods. Those skilled in the art should understand that different regions may use different terms to refer to the same component. The description and claims do not use the difference in name as a way to distinguish components. As mentioned throughout the specification and claims, "comprising" is an open term, so it should be interpreted as "including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve the technical problem within a certain error range and basically achieve the technical effect. The subsequent description of the specification is a preferred implementation mode for implementing the application, but the description is for the purpose of illustrating the general principle of the application, and is not intended to limit the scope of the application. The scope of protection of the present application should be defined by the appended claims.

It should also be noted that the term "comprises", "comprises" or any other variation thereof is intended to cover a non-exclusive inclusion such that a good or system comprising a set of elements includes not only those elements but also includes items not expressly listed. other elements of the product, or elements inherent in the commodity or system. Without further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the article or system comprising said element.

The above description shows and describes several preferred embodiments of the invention, but as previously stated, it should be understood that the invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other embodiments. Combinations, modifications and circumstances, and can be modified within the scope of the inventive concept described herein, by the above teachings or by skill or knowledge in the relevant field. However, changes and changes made by those skilled in the art do not depart from the spirit and scope of the invention, and should be within the protection scope of the appended claims of the invention.

Claims (10)

1. A activated carbon regeneration system, characterized in that it comprises: sequentially connected raw material pretreatment and feeding system, vertical multi-stage regeneration furnace and waste heat recovery system; The raw material pretreatment and feeding system includes a drying furnace, the hot flue gas inlet of the drying furnace is connected with the flue gas main pipe of the combustion heating mechanism of the vertical multi-stage regeneration furnace; the air inlet of the drying furnace is connected with the hot blast furnace The air outlet is connected, the air inlet of the hot blast stove is connected with the exhaust dust collector outlet of the waste heat recovery system; the discharge port of the drying furnace is connected with the inlet of the dry charcoal silo, and the outlet of the dry charcoal silo is connected with the The feed port of the vertical multi-stage regeneration furnace; the exhaust gas outlet of the drying furnace is connected to the flue gas purification device; The vertical multi-stage regenerating furnace includes a furnace body, and the furnace body includes a distributor, a carbonization bin, an activation bin and a regenerated carbon cooler in the order of arrangement up and down, and the distributor is connected to the feed port of the furnace body, so The distributor is provided with a distributor steam inlet; between the carbonization bin and the activation bin or in the activation bin is provided with at least one tail gas outlet, and the tail gas outlet is connected to the tail gas cooler of the waste heat recovery system to enter Gas port; the activation chamber is provided with an activation chamber steam inlet; the carbonization chamber and the activation chamber are respectively provided with at least one combustion heating mechanism; the regenerated carbon cooler and the discharge of the furnace body The steam inlet of the distributor and the steam inlet of the activation chamber are both connected with the heat exchange fluid outlet of the tail gas cooler of the waste heat recovery system. 2. A kind of activated carbon regeneration system as claimed in claim 1, characterized in that, each said combustion heating mechanism comprises two burners, and said two burners are connected through connecting body, and said connecting body is provided with transmission heat element, the burner is installed outside the furnace body, and the connecting body is located inside the furnace body; the two burners are respectively connected to the flue gas main pipe, the gas main pipe and the compressor through three three-way valves. Air main pipe, the flue gas main pipe is also connected to the hot flue gas inlet of the drying furnace, the gas main pipe is also connected to the exhaust gas dust collector outlet of the waste heat recovery system, and the compressed air main pipe is also connected to the compressed air pump. 3. The activated carbon regeneration system according to claim 2, characterized in that, the connecting body can be arranged parallel and/or vertically to the furnace body. 4. An activated carbon regeneration system according to claim 2 or 3, characterized in that the heat transfer element is filled with several porous ceramic regenerators. 5. A kind of active carbon regeneration system as claimed in claim 1, is characterized in that, described waste heat recovery system comprises tail gas cooler, tail gas deduster, sub-steam drum and dust collection tank, the gas outlet of described tail gas cooler is connected with The air inlet of the tail gas dust collector is connected, the dust outlet of the tail gas dust collector is connected with the dust collection tank, and the gas outlet of the tail gas dust collector is connected with the gas main pipe of the combustion heating mechanism and the hot blast stove respectively. The air inlet of the sub-steam drum is connected to each other; the steam outlet of the sub-steam drum is connected to the steam inlet of the activation chamber and the steam inlet of the distributor respectively, the liquid inlet of the sub-steam drum is connected to the desalinated water pipeline, and the steam sub-drum The outlet of the desalinated water circulating pump is connected to the inlet of the desalinated water circulating pump, the outlet of the desalted water circulating pump is connected to the circulating liquid inlet of the regenerated carbon cooler, and the circulating liquid outlet of the regenerated carbon cooler is connected to the heat exchange liquid of the heat exchanger The inlets are connected, and the heat exchange liquid outlet of the heat exchanger is connected to the steam-water inlet of the sub-steam drum. 6. A method for regeneration of activated carbon, characterized in that the regeneration system according to any one of claims 1 to 5 is adopted, and the regeneration method comprises: The activated carbon to be activated is initially dried in a drying oven; The preliminarily dried activated carbon to be activated is introduced into a vertical multi-stage regeneration furnace for activation to obtain activated activated carbon and activated tail gas, and generate combustion flue gas; The activated tail gas and the heat generated are recovered separately through the waste heat recovery system. Among them, the recovered activated tail gas is used as fuel gas after dedusting, and the recovered heat is used to heat desalted water to generate steam, which is used as cloth steam and activation steam respectively; The combustion flue gas is used as a heat source for preliminary drying of the activated carbon to be activated, and the cooled flue gas is discharged after environmental protection treatment, and so on, until the activated carbon is treated. 7. A method for regenerating activated carbon as claimed in claim 6, wherein the activated carbon to be activated is initially dried in a drying oven, and the temperature of the drying oven is controlled at 130°C-200°C, preferably at 150-190°C ; The moisture content of the dry charcoal is 5%-15%, preferably 5%-10%. 8. A kind of activated carbon regeneration method as claimed in claim 6, is characterized in that, described the control parameter that the activated carbon to be activated that is preliminarily dried is activated: the pressure in the hearth of the vertical multi-stage regeneration furnace is -0.01MPaG—0.2 MPaG, preferably -0.01MPaG-0.1MPaG; the temperature of the carbonization chamber is controlled at 440°C-600°C, preferably 500-550°C, and the temperature of the activation chamber is controlled at 600°C-1100°C, preferably 700-900°C. 9. A kind of activated carbon regeneration method as claimed in claim 6, is characterized in that, described preliminary drying activated carbon to be activated is introduced into the vertical multi-stage regeneration furnace for activation, and a part of the steam participating in the activation reaction is cloth steam, and a part is activation steam. 10. A kind of activated carbon regeneration method as claimed in claim 9, is characterized in that, in the activation process, the total consumption Q of cloth steam and described activated steam is calculated according to the following formula: Q=W(Fc×η-, Q : total steam flow, Kg/h; W: dry charcoal flow, Kg/h; Fc: fixed carbon content of dry charcoal, %; η: steam coefficient, 10% to 15%; M: total water content of dry charcoal, %; Wherein, the cloth steam accounts for 20%-50% of the total steam.

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