• Clean Technology
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• v.23 no.3
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• pp.302-307
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• 2017

This study was conducted to evaluate the feasibility of in situ soil flushing for TPH-contaminated soil remediation with column test. The soil texture of the soil was sand and the initial TPH concentration was $9,369mg\; kg^{-1}$. 0.1% Tween-80 was selected as surfactant solution. And the acrylic and the glass syringe columns were used as reactors. In the acrylic column test, 35% of the initial TPH was removed in 1 PV of flushing and approximately 40% in 5 PV and finally 7 PV showed about 60%. The glass column test showed 3 ~ 12% higher removal efficiency than that of acrylic test until 5 PV of flushing. However, there was no difference in TPH removal efficiency when 7 PV of surfactant was finally flushed. Both of alum only and alum+polymer mixed surfactants showed also the best coagulation efficiency in $150mg\;L^{-1}$ of concentraion. When Tween 80 was newly dissolved in 0.1% to the recovered solution after the coagulation treatment, the removal efficiency was increased from 32.0% to 41.0% in comparison to the new 0.1% Tween 80 solution without reuse by coagulation treatment.

• Journal of the Korean Applied Science and Technology
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• v.34 no.2
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• pp.289-295
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• 2017

The International Maritime Organization (IMO) in accordance with the regulations with respect to the combustion gases, such as NOx, SOx generated by the marine engine. The combustion gases must be equipped with a device to reduce emissions from all ships passing through the Baltic SECAs. In Korea, the International Maritime Organization (IMO) and the development of a device for NOx, SOx reduction. Scrubber is used in the ammonia water and the Urea solution in the waste water. The waste water containing ammonium nitrate and ammonium sulfate, react of the NOx and SOx gas. In this study, the recovery of by-product, which contains the waste water was used as an organic solvent extraction method of salting out. Ammonium nitrate and ammonium sulfate, the recovery process. A qualitative analysis of the collected by-product FT-IR analysis. Through the elemental analysis and SEM-EDS, characteristic evaluation was performed with an impurity.

• Journal of the Korean Applied Science and Technology
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• v.34 no.2
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• pp.210-216
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• 2017

Recovery of low level nitric acid and sulfuric acid ions, which were contained in wastewater of a wet scrubber for de-NOx and de-SOx from ship engines, was attempted as fertilizing materials. This study utilized a selective extraction method using four organic solvents to precipitate the solid salts of ammonium nitrate and ammonium sulfate. The IR analysis showed almost same composition of the extracted ammonium salts with a commercial product, and recovery rate of nitrogen and sulfuric ions was 89% and 80% respectively. It was found that the selectivity and solubility consequently could be the crucial factors to recover the low level ions from the waste scrubbing water.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.12
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• pp.2205-2213
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• 2000

To investigate removal efficiency of dissolved matter by NF and RO, a pilot plant was operated for six months using groundwater treated by UF membrane. After the pilot plant operation, we performed autopsy test to identify characteristics of foulant attached on the membrane surface applying the used NF and RO in the pilot plant test. In autopsy test, we measured permeate flux and recovery rate of flux by chemical cleaning in each membrane. We also analyzed chemical cleaning disposal to examine component of foulant. Permeate flux of NF and RO1 showed rapid decline after 100 days of operation. Especially, reduction of specific flux in RO1 was more serious than in NF. Specific flux of RO2 with a low recovery rate resulted in gradual flux decline. Removal efficiencies of dissolved inorganic matters as a conductivity were 76.3%, 88.2% and 95.3% respectively for NF, RO1 and RO2, and RO2 presented the highest removal efficiency. And those of dissolved organic matters as TOC were about 80% for both NF and RO. The specific flux of membranes declined gradually from the feed water inlet to outlet of the membrane module and it showed that membrane fouling increased along the feed flow direction. Namely, concentration of pollutants became higher and volume of feed water was less as the feed flow approached to the outlet. It seemed that major foul ants were Ca consolidated into inorganic material and Si consolidated into organic material on the membrane surface. Fe was a great contribution to irreversible fouling. The SEM results indicated that the organic matter was attached to the first layer, closer to the membrane, and then inorganic matter with tetragonal shape layered over them. We could not observe biofouling because microorganism, which was cause of biofouling, was almost pretreated in UF membrane.