Adsorption of Volatile Organic Compounds on Fluidized Activated Carbon Bed

Abstract

Background: Fixed bed adsorber as a controlling method for volatile organic compounds is widely used. However, these adsorbers are facing some issues such as high pressure drop, non-uniformed distribution of fluid, channeling and blockage. Fluidized bed adsorber as a novel method solves lots of these limitations. Objectives: This research aimed at investigating factors affecting the adsorption of vapors of VOCs on fluidized bed adsorbers. Materials and Methods: To assess adsorption, an annular fluidized bed reactor was designed and charged with activated carbon particles with size of 50 -100 and 100 -140 American society for testing and materials(ASTM) standard mesh, respectively. To calculate the minimum fluidization velocity, Ergun equation was used. The effect of inlet concentration (400 -600 ppmv), fluidization velocity, particle size distribution and breakthrough time were investigated under a steady state. Results: Tests indicated that by increasing flow rate from 0.3 (L/min), bubbles formed in the bed and the bed's pressure drop suddenly declined. The adsorption test indicated that, when Q = 3 (L/min), the removal efficiency of activated carbon (AC) (100 -140 mesh ASTM), was nearly 100% up to 99 min and it reached zero after 260 min. For 50 -100 Mesh AC, the removal efficiency was close to 100% up to 95 min and it reached zero after 270 Minutes. The results also indicated that increasing initial concentration and flow rate reduces breakthrough time. However, two flow rates, 2 and 3 (L/min) Comparison, did not reveal significant differences in the removal efficiency of the bed before breakthrough time. Conclusions: Results indicated that annular fluidized bed reactor's adsorbers are useful techniques for VOCs adsorption. Comparison of two particle ranges indicates that in all concentrations and all flow rates of the experiments, smaller particle size adsorption are better. In superficial velocity above the minimum fluidization velocity, pressure drop of fluidized beds are less than the pressure drop of fixed beds. So fluidized bed systems are more applicable for smaller adsorber particles.

Adsorption of Sulfur Dioxide on Clinoptilolite/Nano Iron Oxide and Natural Clinoptilolite

“…In the adsorption process, molecules physically adsorb to the adsorbent and separate from the gas stream. When all the pores of the adsorbent are filled, it is unable to adsorb more contaminant (41). Zhang et al found that with increasing contact time, the SO 2 removal efficiency by CaO as desulfurizers decreased; this is similar to the results of the current study (42).…”

Photocatalytic degradation of VOCs from air stream using Mo:TiO2/GAC nanocomposites

“…It has been used for a long time and is still used today as a successful adsorbent to remove pollutant gases and vapors [2,44,53]. Thus, RE of as high as 100% can be obtained with the good design of the reactor and appropriate amount of carbon granules [54,55]. But, the main drawback with the bare GAC is breakthrough and adsorbent saturation over time as observed obviously in this study.…”

Estimation of Volatile Organic Compounds (VOCs) and Human Health Risk Assessment of Simulated Indoor Environment Consisting of Upholstered Furniture Made of Commercially Available Foams

“…ere are three levels of this problem handling source, ventilation, and air cleaning. Several methods have been reported to control VOCs in the indoor environment such as toluene adsorption using activated carbon [15,23], catalytic or UV methods [22], an additive in foam formulation [17], thermal oxidation, and bio-treatment [13,14] methods. Every method comes with its advantages and limitations that should be considered based on individual indoor conditions.…”

“…Generally, VOCs can be controlled at source (during the manufacturing of the indoor product), ventilation, and air-cleaning [12]. e reported methods for air-cleaning include botanical puri cation, Catalytic combustion, Membrane Separation, Zeolite based adsorption, Bio-ltration, Absorption, and activated carbon-based adsorption [13][14][15]. Every method has its advantages and disadvantages, and the best suitable method can vary from site to site.…”