• KSBB Journal
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• v.14 no.4
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• pp.452-459
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• 1999

A two-stage continuous stirred tank reactor (CSTR)/trickling biofilter reactor (TBR) system was developed for the degradation of gas-phase trichloroethlene (TCE) using Methylosinus trichoporium OB3b. Mrthylosinus trichosporium OB3b was immobilized on activated carbons in TBR and the microbial growth reactor of a CSTR was coupled for the reactivation of the deactivated cells during TCE degradation. The effect of operation variables on TCE conversion and degradation rate were studied. At inlet TCE concentrations ranging from 10 to 80 $\mu$mol/L, TCE degradation rate was increased up to 525 mg TCE/Lㆍday with 75% conversion. The TCE degradation rates were also increased with increse in broth recycle flow rate, gas flow rate and dilution rate. When the temperature of TBR was changed from 3$0^{\circ}C$ to 15$^{\circ}C$, TCE degradation rate and TCE conversion were increased due to the enhanced TCE transfer from gas-phase. The two-stage reactor system was found to be stable and has been operated for more than 270 days.

• Clean Technology
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• v.19 no.4
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• pp.370-378
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• 2013

This review has shown the capability of MOFs and ZIFs materials to adsorb $CO_2$ under typical PSA temperatures and pressures. The usual operating conditions are adsorption temperatures of $15{\sim}40^{\circ}C$ and adsorption pressures of 4~6 bar based on numerous PSA processes which are widely employed in gases industry for adsorptive separation of $CO_2$. The extent of $CO_2$ adsorption on the microporous materials depends on the metal species and organic linkers existing in the frameworks. The pore size and the surface area, and the process variables are the key parameters to be associated with the efficiency of the adsorbents, particularly adsorption pressures if other variables are comparable each other. The MOFs and ZIFs materials require high pressures greater than 15 bar to yield significant $CO_2$ uptakes. They possess a $CO_2$ adsorption capacity which is very similar to or less than that of conventional benchmark adsorbents such as zeolites and activated carbons. Consequently, those materials have been much less cost-effective for adsorptive $CO_2$ separation to date because of very high production price and the absence of commercially-proven PSA processes using such new adsorbents.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.10
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• pp.573-577
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• 2015

There are difficulties in removing wood tar wastewater coming from the power plants that use wood-based fuels due to its intermittent occurrences and severe changes in the amount and concentration. This study investigated the treatment characteristics through physicochemical treatment, an improved method from the existing ones using bag filters and activated carbons to treat wood tar wastewater. In the case of chemical properties of wood tar wastewater, the content of phenols was found to be more than two times higher than that of guaiacols and carbohydrates. Installation is done to ensure that NaOH and PAC are injected automatically according to the change of pH, and then pH, turbidity and SS of the final treated water were examined. The results were 5.9, 12.6 NTU and 15.1 mg/L respectively, which confirmed the possibility of the treated water as circulation water of power plants. In the physical treatment process using a conventional bag filter, removal efficiency of chemicals was about 20%, but the treatment efficiency was improved to show chemical removal efficiency of about 80% through flocculation and sedimentation.