A method for simultaneous desorption and resource recovery of multiple pollutants in adsorption-saturated activated char

Abstract

This invention discloses a method for the simultaneous desorption and resource recovery of multiple pollutants from adsorbed saturated activated carbon, comprising the following steps: combining adsorbed saturated activated carbon with a metal-based catalyst; and applying plasma to simultaneously desorb and recover SO2 and VOCs adsorbed by the activated carbon. This invention directly and simultaneously achieves the resource recovery and harmless treatment of multiple pollutants during the regeneration and desorption process of adsorbed saturated activated carbon, simplifying the complexity of the regeneration system and potentially reducing system costs. In this method, VOCs are directly used as a reducing agent to simultaneously achieve sulfur resource recovery and harmless degradation of VOCs, eliminating the need for external reducing agents or oxidants, thus saving resources and reducing costs.

Description

Technical Field

[0001] This invention relates to the field of multiple pollutant analysis and resource recovery technology in adsorption-saturated activated carbon, and particularly to a method for simultaneous analysis and resource recovery of multiple pollutants in adsorption-saturated activated carbon. Background Technology

[0002] China consumes nearly 2 billion tons of coal annually for power generation, and the development and utilization of coal's fuel properties constitute a crucial foundation for China's energy industry and economic development. During the transition from old to new energy systems, the clean and efficient utilization of coal remains a critical issue for the period leading up to carbon peaking. Over the past decade, increasingly stringent emission standards for environmental pollutants have created an urgent need for technologies for deep, combined / synergistic control of pollutants. On the one hand, traditional pollutant control technologies, such as wet desulfurization, face sustainable development challenges. At least 125 million tons of high-quality limestone are mined annually, damaging the ecological environment; 215 million tons of low-quality gypsum are produced as a byproduct, which is large in quantity but low in quality and difficult to utilize; and water consumption is high, making zero discharge of desulfurization wastewater difficult. On the other hand, unconventional pollutants such as volatile organic compounds (VOCs) generated from coal combustion, as important precursors to regional atmospheric complex pollution, are also gradually coming into focus.

[0003] Activated carbon possesses advanced physical and chemical activity, exhibiting adsorption and catalytic activity for a variety of pollutants. It shows application potential in both the resource-based conversion of conventional pollutant SO2 and the adsorption and removal of unconventional pollutants such as VOCs. Currently, activated carbon with high adsorption capacity is used in the integrated removal of multiple pollutants, including SO2 and VOCs. In practical pollutant removal processes, activated carbon regeneration is a crucial step. Saturated activated carbon can only be reused multiple times through regeneration, and the regeneration process directly impacts the system's economics and stability.

[0004] Current saturated activated coke regeneration processes mainly rely on thermal regeneration to separately analyze various pollutants, which are then subjected to resource recovery / harmless treatment. This results in complex regeneration systems with high energy consumption. Summary of the Invention

[0005] The present invention aims to at least partially solve one of the technical problems in the related art.

[0006] Therefore, embodiments of the present invention propose a method for the simultaneous desorption and resource recovery of multiple pollutants in an adsorption-saturated activated char.

[0007] This invention proposes a method for the simultaneous desorption and resource recovery of multiple pollutants in an adsorption-saturated activated char, comprising the following steps:

[0008] (a) Combining adsorption-saturated activated coke with a metal-based catalyst;

[0009] (b) Applying plasma allows for the simultaneous desorption and resource recovery of SO2 and VOCs adsorbed by activated carbon.

[0010] In some embodiments, under the action of the plasma and the metal-based catalyst, VOCs act as a reducing agent to reduce SO2 to elemental sulfur, while VOCs are oxidized to CO2 and H2O, thereby achieving simultaneous desorption and resource recovery of SO2 and VOCs.

[0011] In some embodiments, step (a) specifically involves: mixing the adsorbed saturated activated coke with the metal-based catalyst after crushing and then extruding and compounding them.

[0012] In some embodiments, the metal-based catalyst comprises not less than 10 wt%.

[0013] In some embodiments, the metal-based catalyst is at least one selected from FeS, ZnS, CeO2, TiO2, and Al2O3.

[0014] In some embodiments, the plasma action in step (b) is a microwave thermal plasma or a low-temperature plasma induced by dielectric barrier discharge.

[0015] In some embodiments, the power of the microwave thermal plasma is 500-1000W.

[0016] In some embodiments, the voltage of the dielectric barrier discharge is 0-10kV.

[0017] In some embodiments, the microwave thermal plasma is generated using a microwave thermal reactor.

[0018] In some embodiments, the low-temperature plasma induced by the dielectric barrier discharge is generated using a dielectric barrier discharge electrode.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] This invention enables the simultaneous and direct resource recovery and harmless treatment of multiple pollutants during the regeneration and desorption process of adsorbed saturated activated carbon, simplifying the complexity of the regeneration system and having the potential to reduce system costs.

[0021] The method of this invention directly uses VOCs as a reducing agent to simultaneously realize sulfur resource recovery and harmless degradation of VOCs, without the need for external reducing agents or oxidants, thus saving resources and reducing costs. Attached Figure Description

[0022] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0023] Figure 1 This is a flowchart of the method for simultaneous desorption and resource recovery of multiple pollutants in an adsorbed activated char according to the present invention. Detailed Implementation

[0024] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the present invention, and should not be construed as limiting the present invention.

[0025] The following describes, with reference to the accompanying drawings, a method for simultaneous desorption and resource recovery of multiple pollutants in an adsorption-saturated activated char according to an embodiment of the present invention.

[0026] like Figure 1 As shown, the method for simultaneous desorption and resource recovery of multiple pollutants in an adsorbed and saturated activated carbon according to the present invention includes the following steps:

[0027] (a) Combining adsorption-saturated activated coke with a metal-based catalyst;

[0028] (b) Applying plasma allows for the simultaneous desorption and resource recovery of SO2 and VOCs adsorbed by activated carbon.

[0029] In this invention, the activated carbon saturated with adsorption is activated carbon saturated after adsorbing SO2 and VOCs. Under the action of plasma and metal-based catalyst, VOCs act as a reducing agent to reduce SO2 to elemental sulfur, while VOCs are oxidized to CO2 and H2O, thus realizing the simultaneous desorption and resource utilization of SO2 and VOCs.

[0030] The specific process of combining the adsorption-saturated activated coke with the metal-based catalyst in step (a) is as follows: the adsorption-saturated activated coke and the metal-based catalyst are crushed, mixed, and then extruded and compounded. The crushing process can be achieved using a grinding pestle, and the extrusion process can be achieved using a tablet press. The proportion of the compounded metal-based catalyst is not less than 10 wt%, wherein the metal-based catalyst is a metal oxide or a metal sulfide, and the metal-based catalyst is at least one of FeS, ZnS, CeO2, TiO2, and Al2O3.

[0031] In step (b), the plasma is generated by either microwave thermal plasma or low-temperature plasma induced by dielectric barrier discharge. The microwave thermal plasma has a power of 500-1000W and is generated using a microwave thermal reactor. The dielectric barrier discharge has a voltage of 0-10kV and is generated using a dielectric barrier discharge electrode.

[0032] The following specific embodiments illustrate the method for simultaneous desorption and resource recovery of multiple pollutants in an adsorption-saturated activated char according to the present invention.

[0033] Example 1:

[0034] 2g of activated coke saturated with SO2 and VOCs was mixed with 0.4g of ZnS and 0.4g of CeO2 metal-based catalyst after crushing and extrusion composite. The composite activated coke and metal-based catalyst were placed between 8kV dielectric barrier discharge electrodes and a voltage of 8kV was applied. The SO2 conversion rate was measured to be 85%, the elemental sulfur selectivity to be 75%, and the VOCs conversion rate to be 90%. The elemental sulfur selectivity to be 75% means that 75% of the converted SO2 was converted into elemental sulfur.

[0035] Example 2:

[0036] 2g of activated coke saturated with SO2 and VOCs was mixed with 0.4g of ZnS and 0.4g of CeO2 metal-based catalyst after crushing and extrusion compounding. The compounded activated coke and metal-based catalyst were placed in a microwave reactor and microwaves of 700W were applied. The SO2 conversion rate was measured to be 60%, the elemental sulfur selectivity to be 55%, and the VOCs conversion rate to be 70%. The elemental sulfur selectivity to be 55% means that 55% of the converted SO2 was converted into elemental sulfur.

[0037] Comparative Example 1:

[0038] Two g of activated char, saturated with adsorbed SO2 and VOCs, was placed directly between dielectric barrier discharge electrodes. An 8 kV voltage was applied, and the SO2 conversion rate was measured to be 20%, while the VOCs conversion rate was 30%.

[0039] As can be seen from Example 1 and Comparative Example 1, when activated coke that has reached saturation of SO2 and VOCs is not combined with a metal-based catalyst, but instead plasma is directly applied to simultaneously desorb and recycle the SO2 and VOCs adsorbed by the activated coke, the conversion rates of SO2 and VOCs are both low. The presence of a metal-based catalyst can greatly improve the conversion rate of simultaneous desorption and recycling of SO2 and VOCs adsorbed by the activated coke.

[0040] Comparative Example 2:

[0041] 4g of activated coke saturated with SO2 and VOCs was mixed with 0.2g of ZnS and 0.2g of CeO2 metal-based catalyst after crushing and extrusion composite. The composite activated coke and metal-based catalyst were placed between 8kV dielectric barrier discharge electrodes and a voltage of 8kV was applied. The SO2 conversion rate was measured to be 65%, the elemental sulfur selectivity to be 55%, and the VOCs conversion rate to be 70%. The elemental sulfur selectivity of 75% means that 75% of the converted SO2 was converted into elemental sulfur.

[0042] According to Example 1 and Comparative Example 2, when the proportion of metal-based catalyst is less than 10 wt%, the conversion rates of SO2 and VOCs both decrease.

[0043] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms may refer to different embodiments or examples. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0044] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0045] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A method for simultaneous desorption and resource recovery of multiple pollutants from adsorption-saturated activated coke, characterized in that, The method comprises the following steps: (a) mixing the adsorption-saturated activated coke with a metal-based catalyst, wherein the proportion of the metal-based catalyst is not less than 10wt%, and the metal-based catalyst is ZnS and CeO2; (b) applying plasma action to simultaneously desorb and recycle the SO2 and VOCs adsorbed by the activated coke, wherein, under the action of the plasma and the metal-based catalyst, the VOCs are used as a reducing agent to reduce the SO2 into elemental sulfur, and the VOCs are oxidized into CO2 and H2O, thereby achieving the simultaneous desorption and recycling of the SO2 and VOCs, In the step (a), the adsorption-saturated activated coke and the metal-based catalyst are crushed, mixed, and extruded to be compounded, and in the step (b), the plasma action is a microwave thermal plasma or a low-temperature plasma induced by dielectric barrier discharge.

2. The method of claim 1, wherein, The power of the microwave thermal plasma is 500-1000W.

3. The method of claim 1, wherein, The voltage of the dielectric barrier discharge is 8-10kV.

4. The method of claim 2, wherein, The microwave thermal plasma is generated by a microwave thermal reactor.

5. The method of claim 3, wherein, The low-temperature plasma induced by dielectric barrier discharge is generated by a dielectric barrier discharge electrode.

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