Activated carbon adsorption and regeneration method for advanced treatment of coking RO concentrated water

Abstract

The invention relates to the technical field of coking wastewater treatment, in particular to an activated carbon adsorption and regeneration method for advanced treatment of coking RO concentrated water. Comprising the following steps: pretreating activated carbon; performing dynamic adsorption; performing regeneration operation; and recycling. The invention provides an activated carbon adsorption and regeneration method for advanced treatment of coking RO concentrated water, and aims to solve the problems of low regeneration efficiency, poor structural stability, insufficient dynamic adsorption performance and short cycle life of activated carbon in the prior art. By optimizing coal-based activated carbon type selection, a dynamic adsorption process and a dual-mode regeneration strategy, efficient advanced treatment of coking RO concentrated water and cyclic utilization of activated carbon are realized.

Description

Technical Field

[0001] This invention relates to the field of coking wastewater treatment technology, and in particular to an activated carbon adsorption and regeneration method for deep treatment of coking RO concentrate. Background Technology

[0002] Coking reverse osmosis (RO) concentrate is a high-salt, highly toxic, and recalcitrant byproduct generated during the advanced treatment of coking wastewater. Its complex composition includes high concentrations of dissolved solids (TDS), chemical oxygen demand (COD), benzene compounds, and polycyclic aromatic hydrocarbons, among other harmful substances. Direct discharge of this wastewater would pose a serious threat to the ecological environment and human health. Activated carbon adsorption technology, due to its highly efficient removal of organic matter, is widely used in the field of advanced industrial wastewater treatment. Among these, coal-based activated carbon, with its high specific surface area, well-developed pore structure, and excellent mechanical strength, demonstrates significant advantages in treating wastewater with high salinity and high organic loads.

[0003] Although activated carbon adsorption technology has a certain degree of universality, it still has significant limitations in treating coking RO concentrate: traditional thermal regeneration methods can partially restore adsorption capacity, but high temperatures easily lead to micropore collapse, a decrease in specific surface area, and degradation of functional groups in activated carbon, resulting in a sharp decline in adsorption performance after multiple regenerations; chemical regeneration causes less damage to the pore structure, but its regeneration efficiency is low, making it difficult to effectively desorb highly adsorbent pollutants in coking RO concentrate. Conventional activated carbon (such as charcoal) has short breakthrough time and low saturated adsorption capacity under high salinity and high organic load conditions, failing to meet the economic requirements for continuous treatment of coking RO concentrate. Existing regeneration technologies struggle to balance adsorption performance recovery with microstructural integrity, resulting in a limited number of times activated carbon can be reused and significantly increasing operating costs. Summary of the Invention

[0004] This invention provides a method for activated carbon adsorption and regeneration in the deep treatment of coking RO concentrate, aiming to solve the problems of low regeneration efficiency, poor structural stability, insufficient dynamic adsorption performance, and short cycle life of activated carbon in existing technologies. By optimizing the selection of coal-based activated carbon, the dynamic adsorption process, and the dual-mode regeneration strategy, efficient deep treatment of coking RO concentrate and recycling of activated carbon are achieved.

[0005] The technical solution adopted in this invention is: a method for activated carbon adsorption and regeneration for deep treatment of coking RO concentrate, comprising the following steps:

[0006] Step 1, Activated carbon pretreatment: Soak coal-based granular activated carbon (particle size 80–120 mesh, specific surface area 850±20 m² / g) in 1 mol / L hydrochloric acid for 2 h, rinse with deionized water until neutral, and dry at 105℃ for 12 h.

[0007] Step 2, dynamic adsorption: The pretreated activated carbon is packed into a fixed bed adsorption column (inner diameter 2cm, packing height 30cm), and coking RO concentrate (COD 950±50mg / L, TDS 18000±2000mg / L) is introduced at a flow rate of 12mL / min, with an empty bed flux of 5BV / h and a temperature of 25±1℃.

[0008] Step 3, regeneration operation: This is divided into thermal regeneration and chemical regeneration. Thermal regeneration involves placing saturated activated carbon in a tube furnace and heating it to 600℃ at a rate of 10℃ / min under a nitrogen atmosphere (flow rate 50mL / min), then holding it at that temperature for 30min. Chemical regeneration involves soaking saturated activated carbon in 0.5mol / L NaOH solution for 2h, followed by ultrasonic treatment (frequency 40kHz, power 200W) for 30min, rinsing until neutral, and then drying at 105℃.

[0009] Step 4, Recycling: The regenerated activated carbon is recycled and used for adsorption in step 2, with the number of cycles ≤ 5 times.

[0010] As a further improvement of the present invention, the iodine value of the coal-based granular activated carbon is ≥1050mg / g and the ash content is ≤4.2%.

[0011] As a further improvement of the present invention, the coking RO concentrate in step two needs to meet the following requirements: total benzene concentration of 120±10 mg / L, polycyclic aromatic hydrocarbon concentration of 25±3 mg / L, and pH of 8.5±0.3.

[0012] As a further improvement of the present invention, the breakthrough time of dynamic adsorption in step two is ≥7.2h.

[0013] As a further improvement of the present invention, the thermal regeneration recovery rate in step three is ≥89.5%, and the chemical regeneration recovery rate is ≥72.3%.

[0014] As a further improvement of the present invention, the thermal regeneration temperature range in step three is 400–600℃, preferably 600℃.

[0015] As a further improvement of the present invention, the concentration of NaOH used in the chemical regeneration in step three is 0.1–1.0 mol / L, preferably 0.5 mol / L.

[0016] As a further improvement of the present invention, the micropore ratio of the regenerated activated carbon is ≥52%, and the average pore size is ≤2.4nm.

[0017] As a further improvement of the present invention, the method is applicable to the deep treatment of coking RO concentrate with COD≤1200mg / L, and simultaneously removes benzene series compounds and polycyclic aromatic hydrocarbons.

[0018] The beneficial effects of the present invention are as follows: (1) The present invention innovatively adopts a dual-mode synergistic strategy of thermal regeneration and chemical regeneration. The high-temperature thermal regeneration under nitrogen protection efficiently restores the adsorption performance, while the chemical regeneration combined with alkali solution and ultrasound effectively maintains the integrity of the pore structure. The two complement each other to overcome the contradiction between "efficiency improvement" and "structural damage" in traditional regeneration technology. Thermal regeneration significantly inhibits micropore collapse through precise temperature control, while chemical regeneration utilizes ultrasonic cavitation to enhance mass transfer. While efficiently desorbing pollutants, it maximizes the protection of the activated carbon microstructure.

[0019] (2) This invention achieves simultaneous and efficient removal of high concentrations of organic matter and characteristic pollutants (such as benzene series compounds and polycyclic aromatic hydrocarbons) in coking RO concentrate by selecting coal-based activated carbon with specific physicochemical indicators and optimizing fixed-bed adsorption process parameters. The system exhibits excellent anti-penetration ability and saturated adsorption capacity under continuous operation conditions, which is significantly better than conventional activated carbon materials and meets the needs of industrial continuous treatment.

[0020] (3) The strict control of the number of cycles and the management of regeneration structure indicators in this invention ensure that the activated carbon maintains stable adsorption performance after multiple regenerations, completely solving the bottleneck of limited regeneration times in traditional processes; it significantly reduces the frequency of activated carbon replacement and overall operating costs, providing an economical and sustainable solution for the large-scale application of deep treatment of coking wastewater. Attached Figure Description

[0021] Figure 1 This is a fitting curve of the pseudo-second-order kinetic model of an activated carbon adsorption and regeneration method for deep treatment of coking RO concentrate according to the present invention.

[0022] Figure 2 This is a comparison of the breakthrough curves of coal-based and wood-based activated carbon in an activated carbon adsorption and regeneration method for deep treatment of coking RO concentrate according to the present invention.

[0023] Figure 3 This is a comparison of SEM images before and after regeneration of an activated carbon adsorption and regeneration method for deep treatment of coking RO concentrate according to the present invention. Detailed Implementation

[0024] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0025] This invention provides a method for activated carbon adsorption and regeneration in the deep treatment of coking RO concentrate, comprising the following steps:

[0026] Step 1, Activated Carbon Pretreatment: Soak coal-based granular activated carbon (particle size 80–120 mesh, specific surface area 850±20 m² / g) in 1 mol / L hydrochloric acid for 2 hours, rinse with deionized water until neutral, and dry at 105℃ for 12 hours. The iodine value of the coal-based granular activated carbon is ≥1050 mg / g, and the ash content is ≤4.2%.

[0027] Step 2, Dynamic Adsorption: Pretreated activated carbon is packed into a fixed-bed adsorption column (inner diameter 2cm, packing height 30cm), and coking RO concentrate (COD 950±50mg / L, TDS 18000±2000mg / L) is introduced at a flow rate of 12mL / min. The empty bed flux is 5BV / h, the temperature is 25±1℃, and the coking RO concentrate must meet the following requirements: total benzene concentration 120±10mg / L, polycyclic aromatic hydrocarbon concentration 25±3mg / L, pH 8.5±0.3, and the breakthrough time of dynamic adsorption ≥7.2h.

[0028] Step 3, Regeneration Operation: This is divided into thermal regeneration and chemical regeneration. Thermal regeneration involves placing saturated activated carbon in a tube furnace and heating it to 600℃ at a rate of 10℃ / min under a nitrogen atmosphere (flow rate 50 mL / min), maintaining this temperature for 30 min. Chemical regeneration involves soaking saturated activated carbon in a 0.5 mol / L NaOH solution for 2 h, followed by ultrasonic treatment (frequency 40 kHz, power 200 W) for 30 min, rinsing until neutral, and drying at 105℃. The thermal regeneration recovery rate is ≥89.5%, and the chemical regeneration recovery rate is ≥72.3%. The thermal regeneration temperature range is 400–600℃, preferably 600℃. The NaOH concentration for chemical regeneration is 0.1–1.0 mol / L, preferably 0.5 mol / L.

[0029] Step 4, Recycling: The regenerated activated carbon is recycled and used for adsorption in step 2, with the number of cycles ≤ 5 times.

[0030] In this invention, the micropore ratio of the regenerated activated carbon is ≥52%, and the average pore size is ≤2.4nm.

[0031] The method in this invention is applicable to the deep treatment of coking RO concentrate with COD≤1200mg / L, and simultaneously removes benzene compounds and polycyclic aromatic hydrocarbons.

[0032] Example:

[0033] Materials and Methods

[0034] (a) Test materials

[0035] To investigate the adsorption and regeneration performance of coal-based activated carbon in the advanced treatment of coking RO concentrate, granular coal-based activated carbon produced by a coal company in Shanxi Province was used. This activated carbon possesses a high specific surface area and excellent organic matter adsorption capacity. Before use, it was soaked in 1 mol / L hydrochloric acid for 2 hours to remove impurities, then rinsed with deionized water until neutral and dried at 105℃ for 12 hours. Specific parameters are detailed in Table 1 below.

[0036] Table 1. Physicochemical properties of experimental materials and water quality parameters

[0037] project Indicator / Concentration Range Activated carbon particle size (mesh) 80–120 Specific surface area (m² / g) 850±20 Iodine value (mg / g) 1050 Ash content (%) 4.2 COD (mg / L) 950±50 TDS (mg / L) 18000±2000 Total concentration of benzene series compounds (mg / L) 120±10 Polycyclic aromatic hydrocarbon concentration (mg / L) 25±3 Electrical conductivity (mS / cm) 28.5 pH 8.5±0.3

[0038] (II) Experimental Procedure

[0039] (1) Static adsorption experiment

[0040] Static adsorption experiments were conducted using a SHA-C type isothermal shaker at 25℃ and 150 rpm, with a reaction volume of 250 mL. The adsorbent was acid-washed and dried coal-based activated carbon with a particle size of 80–120 mesh. pH control experiments were conducted at pH values ​​of 3, 5, 7, 9, and 11, with a carbon dosage of 5 g / L and a reaction time of 360 min, with samples taken at intervals. Dosage experiments were conducted at dosages of 1, 3, 5, 7, and 10 g / L, with samples taken after 240 min of reaction. Kinetic experiments were conducted with a fixed dosage of 5 g / L and sampling times ranging from 0 to 360 min. Isothermal experiments were conducted with an initial COD of 200–1200 mg / L, followed by isothermal shaking until equilibrium was reached. All experiments were performed in triplicate, and the operating procedures were standardized.

[0041] (2) Dynamic adsorption experiment

[0042] A fixed-bed system was constructed to conduct dynamic adsorption experiments using coal-based activated carbon. The adsorption column was made of plexiglass, with an inner diameter of 2 cm and a packing height of 30 cm. It was filled with 50 g of coal-based activated carbon (80–120 mesh size) treated with 1 mol / L HCl and dried at 105 °C. Stainless steel filter screens were used at both ends to fix the packing material. Water was supplied by a BT100-2J peristaltic pump at a flow rate of 12 mL / min, with an empty bed flux of 5 BV / h, and the water flow was from bottom to top. The experimental temperature was controlled at 25 ± 1 °C. The system was run continuously, and water samples were collected every 1 hour to detect COD and benzene series concentrations, and the running time was recorded. Three parallel systems with consistent parameters were set up to ensure comparability of the adsorption process, and wood-based activated carbon experiments were conducted simultaneously for control and verification.

[0043] (3) Regeneration experiment

[0044] To establish a regeneration pathway for coal-based activated carbon, thermal and chemical regeneration experiments were conducted. For thermal regeneration, saturated carbon samples were placed in an SK-G04123K tubular furnace at a nitrogen flow rate of 50 mL / min and a heating rate of 10℃ / min, heated to 400, 500, and 600℃, held at that temperature for 30 min, and then cooled for later use. For chemical regeneration, 0.1, 0.5, and 1.0 mol / L NaOH and HCl solutions were used. Carbon samples were soaked for 2 h, treated with a KQ3200E ultrasonic cleaner for 30 min at a frequency of 40 kHz and a power of 200 W, rinsed until neutral, and then dried at 105℃. The regenerated carbon underwent repeated adsorption under the same conditions, with three parallel groups to ensure consistent parameters. Carbon samples before and after regeneration were vacuum dried and used for BET, SEM, and XPS analysis. Uniform packaging and degassing procedures were followed to ensure data consistency.

[0045] (III) Characterization and Analysis Methods

[0046] To characterize the structural changes of coal-based activated carbon before and after adsorption and regeneration, pore structure, morphology, functional groups, and pollutant concentration were analyzed. Carbon samples were dried at 105℃ for 12 h, and 100 mg was degassed under vacuum at 300℃ for 6 h in an ASAP 2460 instrument for N2 adsorption-desorption testing. 5 mg was sputter-coated with gold, and the surface structure and elemental distribution were observed using a Hitachi SU8010 scanning electron microscope and EDS. Functional group analysis was performed using a Nicolet iS50 infrared spectrometer (4000–500 cm⁻¹) and a Thermo K-Alpha XPS system to resolve the C 1s, O 1s, and N 1s energy levels. Water samples were filtered through a 25 μm membrane; COD was determined by the potassium dichromate method, TOC was analyzed using a TOC-L analyzer, and Benzene series compounds were analyzed using an Agilent 7890B / 5977A gas chromatography-mass spectrometry (GC-MS) system, with standardized operating procedures.

[0047] Results and Analysis

[0048] (a) Static adsorption performance

[0049] Coal-based activated carbon exhibits good static adsorption capacity for organic pollutants in coking RO concentrate, and its adsorption behavior is significantly affected by pH, dosage, reaction time, and concentration.

[0050] (1) At pH 6, the COD removal rate reached 82.3%, and the UV254 decreased simultaneously, indicating that the removal effect of aromatic organic compounds was optimal. Under acidic or alkaline conditions, the adsorption capacity decreased, and the surface charge state interfered with the adsorption behavior.

[0051] (2) As the dosage increases in the range of 1–10 g / L, the unit adsorption capacity increases simultaneously, and it tends to saturate at 5 g / L, thus achieving a balance between adsorption efficiency and dosage utilization efficiency.

[0052] (3) Kinetic analysis showed that the adsorption process conformed to a pseudo-second-order model with a goodness of fit R² of 0.992, which was higher than that of the pseudo-first-order model. The adsorption rate was rapid in the early stage and gradually slowed down in the later stage, mainly due to the limited number of active sites. The fitting model is as follows: , where q t q represents the adsorption amount per unit volume (mg / g) at time t. e To determine the equilibrium adsorption capacity (mg / g), k2 is the pseudo-second-order rate constant (g / (mg·min)). See the fitted curve for details. Figure 1 .

[0053] (4) In the isothermal experiment, the equilibrium adsorption capacity increased nonlinearly with the increase of the initial COD concentration (200–1200 mg / L), which is consistent with the Freundlich model (n=1.85), indicating that the surface heterogeneity and multilayer adsorption characteristics are obvious, and the adsorption capacity in the high concentration region remains stable.

[0054] (ii) Dynamic adsorption and regeneration performance

[0055] Coal-based activated carbon outperforms wood-based activated carbon in the dynamic adsorption of coking RO concentrate, exhibiting significantly higher adsorption capacity and stronger resistance to penetration.

[0056] (1) Penetration behavior: At a flux of 5 BV / h and a packing height of 30 cm, the penetration time of coal-based activated carbon was 7.2 h and that of wood-based activated carbon was 5.1 h, which was 40% longer; the saturated adsorption capacities were 68.2 mg / g and 52.4 mg / g, respectively. Figure 2 The results show that the breakthrough curve of coal-based carbon rises slowly, maintaining a low C value before saturation. t The CO value makes the adsorption process more stable.

[0057] (2) Model Fitting: The experimental data were fitted using the Thomas model to calculate the adsorption capacity and kinetic parameters. The model expression is as follows: , where C t C0 is the effluent concentration, C0 is the influent concentration, q0 is the adsorption capacity per unit mass, m is the carbon mass, V is the cumulative influent volume, and k is the effluent concentration. Th , where is the model constant. The fitting results show that the coal-based carbon curve has a higher goodness of fit and more stable predictive performance.

[0058] (3) Regeneration performance: Thermal regeneration at 600℃ achieved a recovery rate of 89.5%, and the microporous structure was maintained after 30 min of heat preservation; Chemical regeneration using 0.5 mol / L NaOH combined with 40 kHz, 200 W ultrasonic treatment achieved a recovery rate of 72.3%, with high structural retention.

[0059] (4) Structural changes: BET data after thermal regeneration showed that the proportion of micropores decreased from 65% to 52%, the proportion of mesopores increased, and the specific surface area decreased; XPS analysis showed that the C–O and COOH functional groups decreased and the hydrophobicity increased; SEM images showed that the particle outline became blunt and the pore structure partially shrank.

[0060] (III) Structural Evolution and Mechanism of Activated Carbon

[0061] During multiple rounds of adsorption and regeneration, the structure of coal-based activated carbon undergoes continuous evolution, with changes in pore size distribution and surface functional groups, affecting its adsorption performance.

[0062] (1) BET test showed that the specific surface area decreased from 872 to 741 m² / g, the micropore ratio decreased from 65% to 52%, the mesopores increased to 38%, and the average pore size increased from 1.9 to 2.4 nm, reflecting the shrinkage of micropores, the expansion of mesopores, and the tendency of the structure to become more discrete.

[0063] (2) SEM images such as Figure 3 As shown, the surface of the carbon particles changes from rough and uniform to blurred edges and collapsed pores, with obvious interparticle fusion and increased density.

[0064] (3) Functional group changes: The characteristic peaks of C–O, COO–, and C=C at 1035, 1384, and 1610 cm⁻¹ of FTIR were weakened. XPS analysis showed that the surface C / O atomic ratio increased from 2.12 to 2.61, and the COOH and C–O components decreased by 12.6%. The degradation of oxygen-containing functional groups led to a decrease in hydrophilicity.

[0065] (4) Effects of adsorption mechanism: Changes in pore structure and functional groups cause the adsorption mechanism to shift from chemical adsorption to physical filling as the main process. The π–π interaction weakens, the hydrogen bonding ability decreases, and the selective adsorption of polar pollutants is reduced. Although regeneration can partially restore performance, it is accompanied by irreversible microstructure loss.

[0066] in conclusion

[0067] Coal-based activated carbon exhibits good dynamic adsorption capacity and structural stability in coking RO concentrate treatment, and has potential for engineering applications. Specifically, (1) thermal regeneration can efficiently restore adsorption performance at 600℃, which is suitable for high-intensity applications; chemical regeneration is mild and helps maintain the pore structure, making it suitable for cyclic use. (2) Multiple regenerations cause a decrease in the proportion of micropores and loss of functional groups, and the adsorption mechanism changes from chemical to physical, which weakens the ability to remove polar pollutants and limits the service life. (3) It is recommended to develop composite functional carbon materials, introduce magnetic components to improve separation efficiency, or load oxides to enhance catalytic performance, and optimize cycle stability and pollutant adaptability.

[0068] In summary, the activated carbon adsorption and regeneration method for advanced treatment of coking RO concentrate of this invention demonstrates significant effectiveness in the advanced treatment of coking RO concentrate, effectively removing pollutants such as organic matter from the water and exhibiting good regeneration performance. Through pretreatment, dynamic adsorption, regeneration, and recycling of coal-based activated carbon, highly efficient treatment of coking RO concentrate is achieved. Compared to wood-based activated carbon, coal-based activated carbon performs better in dynamic adsorption, exhibiting longer breakthrough time, larger saturated adsorption capacity, and more stable adsorption process. Furthermore, both thermal and chemical regeneration methods can restore the adsorption performance of activated carbon to some extent, allowing selection based on different application scenarios and requirements. However, multiple regeneration cycles can lead to changes in the structure and properties of the activated carbon, altering the adsorption mechanism and weakening its ability to remove polar pollutants. In the future, the development of composite functional carbon materials and other methods is expected to further optimize the cycle stability and adaptability to pollutants of this method, providing a more effective solution for the advanced treatment of coking RO concentrate.

[0069] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for activated carbon adsorption and regeneration in the deep treatment of coking RO concentrate, characterized in that, Includes the following steps: Step 1, Activated carbon pretreatment: Soak coal-based granular activated carbon (particle size 80–120 mesh, specific surface area 850±20 m² / g) in 1 mol / L hydrochloric acid for 2 h, rinse with deionized water until neutral, and dry at 105℃ for 12 h. Step 2, dynamic adsorption: The pretreated activated carbon is packed into a fixed bed adsorption column (inner diameter 2cm, packing height 30cm), and coking RO concentrate (COD 950±50mg / L, TDS 18000±2000mg / L) is introduced at a flow rate of 12mL / min, with an empty bed flux of 5BV / h and a temperature of 25±1℃. Step 3, regeneration operation: This is divided into thermal regeneration and chemical regeneration. Thermal regeneration involves placing saturated activated carbon in a tube furnace and heating it to 600℃ at a rate of 10℃ / min under a nitrogen atmosphere (flow rate 50mL / min), then holding it at that temperature for 30min. Chemical regeneration involves soaking saturated activated carbon in 0.5mol / L NaOH solution for 2h, followed by ultrasonic treatment (frequency 40kHz, power 200W) for 30min, rinsing until neutral, and then drying at 105℃. Step 4, Recycling: The regenerated activated carbon is recycled and used for adsorption in step 2, with the number of cycles ≤ 5 times.

2. The activated carbon adsorption and regeneration method for deep treatment of coking RO concentrate according to claim 1, characterized in that, The coal-based granular activated carbon has an iodine value ≥1050mg / g and an ash content ≤4.2%.

3. The activated carbon adsorption and regeneration method for deep treatment of coking RO concentrate according to claim 1, characterized in that, In step two, the coking RO concentrate must meet the following requirements: total benzene concentration of 120±10 mg / L, polycyclic aromatic hydrocarbon concentration of 25±3 mg / L, and pH of 8.5±0.

3.

4. The activated carbon adsorption and regeneration method for deep treatment of coking RO concentrate according to claim 1, characterized in that, The breakthrough time of dynamic adsorption in step two is ≥7.2h.

5. The activated carbon adsorption and regeneration method for deep treatment of coking RO concentrate according to claim 1, characterized in that, In step three, the thermal regeneration recovery rate is ≥89.5%, and the chemical regeneration recovery rate is ≥72.3%.

6. The activated carbon adsorption and regeneration method for deep treatment of coking RO concentrate according to claim 1, characterized in that, The thermal regeneration temperature range in step three is 400–600℃, preferably 600℃.

7. The activated carbon adsorption and regeneration method for deep treatment of coking RO concentrate according to claim 1, characterized in that, The concentration of NaOH used in the chemical regeneration in step three is 0.1–1.0 mol / L, preferably 0.5 mol / L.

8. The activated carbon adsorption and regeneration method for deep treatment of coking RO concentrate according to claim 1, characterized in that, The micropore ratio of the regenerated activated carbon is ≥52%, and the average pore size is ≤2.4nm.

9. The method according to any one of claims 1–8, characterized in that, The method is applicable to the deep treatment of coking RO concentrate with COD≤1200mg / L, and simultaneously removes benzene compounds and polycyclic aromatic hydrocarbons.

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