Removal through adsorption is the most widely used and effective treatment method for volatile organic compounds (VOCs) in exhaust gases. However, at high temperatures and humidity, adsorption is competitive due to the presence of moisture and unsmooth physical adsorption thereby deteriorating adsor...
Removal through adsorption is the most widely used and effective treatment method for volatile organic compounds (VOCs) in exhaust gases. However, at high temperatures and humidity, adsorption is competitive due to the presence of moisture and unsmooth physical adsorption thereby deteriorating adsorption performance. Therefore, water adsorption honeycomb (WAH) and VOCs adsorption honeycomb (VAH) were prepared to improve VOCs adsorption at high temperatures and humidity. Adsorbed toluene amounts on single honeycomb (SH), containing only VAH, and combined honeycomb (CH), containing WAH and VAH, were determined. Further, the toluene adsorption rates of honeycomb adsorbents mounted on rotary systems, VAH-single rotor (SR) and WAH/VAH-dual rotor (DR) were determined. Toluene adsorption by WAH/VAH-CH (inlet temperature: 40-50℃; absolute humidity: 28-83 gH2O/kg-dry air) was 1.6 times that by VAH-SH, and the water adsorption efficiency of WAH/VAH-CH was 1.7 times that of VAH-SH. The adsorption/removal efficiency of the WAH/VAH-DR (inlet temperature: 45℃; absolute humidity: 37.5 gH2O/kg-dry air) was 3% higher than that of VAH-SR. This indicates that the WAH at the rotor inlet selectively removed water, thereby improving the adsorption efficiency of the VAH at the outlet.
Removal through adsorption is the most widely used and effective treatment method for volatile organic compounds (VOCs) in exhaust gases. However, at high temperatures and humidity, adsorption is competitive due to the presence of moisture and unsmooth physical adsorption thereby deteriorating adsorption performance. Therefore, water adsorption honeycomb (WAH) and VOCs adsorption honeycomb (VAH) were prepared to improve VOCs adsorption at high temperatures and humidity. Adsorbed toluene amounts on single honeycomb (SH), containing only VAH, and combined honeycomb (CH), containing WAH and VAH, were determined. Further, the toluene adsorption rates of honeycomb adsorbents mounted on rotary systems, VAH-single rotor (SR) and WAH/VAH-dual rotor (DR) were determined. Toluene adsorption by WAH/VAH-CH (inlet temperature: 40-50℃; absolute humidity: 28-83 gH2O/kg-dry air) was 1.6 times that by VAH-SH, and the water adsorption efficiency of WAH/VAH-CH was 1.7 times that of VAH-SH. The adsorption/removal efficiency of the WAH/VAH-DR (inlet temperature: 45℃; absolute humidity: 37.5 gH2O/kg-dry air) was 3% higher than that of VAH-SR. This indicates that the WAH at the rotor inlet selectively removed water, thereby improving the adsorption efficiency of the VAH at the outlet.
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제안 방법
In this study, WAH/VAH-CH was prepared and evaluated on a fixed bed continuous adsorption/desorption system. WAH/VAH-DR was used for the evaluation by mounting WAH/VAH-CH on a rotary system.
4(a) shows the toluene adsorption capacity of VAH-SH as a function of temperature. Input gas temperatures of 40, 50, and 60℃, absolute humidity of 28.5 gH2O/kg-dry air, initial toluene concentration of 100 ppm, and GHSV of 20,000 /h were considered in this study. Adsorption was carried out continuously to measure the toluene adsorption amount.
The shape, size, and distribution of particles on the surface of the WAH and VAH, fabricated in this study, were analyzed via scanning electron microscopy (SEM, TESCAN, Mira 3 LMV FEG, Czech). To determine the pore characteristics of the adsorbent, Brunauer-Emmett-Teller (BET) specific surface area (SBET), total pore volume (VT), and average pore diameter (Dp) were measured using a BET surface area analyzer (Micromeritics, ASAP2010, USA).
대상 데이터
Further, WAH-SR and VAH-SR with dimensions of 500 mm (diameter), 200 and 400 mm (length) was used to confirm the adsorption/removal efficiency. The WAH/VAH-DR, measuring 500 mm in diameter and 600 mm in total length, was fabricated by combining the desiccant and adsorbent in a ratio of 1:2 (v/v).
1. The experimental apparatus consisted of an adsorbate generation module, adsorbent filling module, and analysis module. Toluene was injected into the adsorbent generation module at a constant concentration of 100 ppm using a mass flow controller.
The fabricated WAH and VAH was cut cylinders measuring 100 mm in diameter, 100 and 300 mm in length to prepare the WAH-SH and VAH-SH, respectively. The fabricated WAH and VAH were combined in a length ratio of 1:3 (v/v) at the adsorption honeycomb and then cut into cylinders measuring 100 mm in diameter and 400 mm in total length to prepare the WAH/VAH-CH.
ZSM-5 zeolite (SiO2/Al2O3 molar ratio > 100, UOP) powder was used as the adsorbent for the VAH.
이론/모형
The shape, size, and distribution of particles on the surface of the WAH and VAH, fabricated in this study, were analyzed via scanning electron microscopy (SEM, TESCAN, Mira 3 LMV FEG, Czech). To determine the pore characteristics of the adsorbent, Brunauer-Emmett-Teller (BET) specific surface area (SBET), total pore volume (VT), and average pore diameter (Dp) were measured using a BET surface area analyzer (Micromeritics, ASAP2010, USA).
후속연구
) would be performed. It seems likely that the dual rotary adsorption system suggested by this study suitable for the air pollution control technology for a variety of VOCs emissions sources, if the results of this study are successful to design by determining the suitable operation conditions.
However, we have not identified the adsorption tendency and efficiency of the various VOCs in this study. Therefore, further studies for improving the efficiency of dehumidification and VOCs adsorption using the dual rotary adsorption system under various conditions (e.g., number of revolutions, types and concentrations of VOCs, composition ratio of desiccant and VOCs adsorbent, etc.) would be performed. It seems likely that the dual rotary adsorption system suggested by this study suitable for the air pollution control technology for a variety of VOCs emissions sources, if the results of this study are successful to design by determining the suitable operation conditions.
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