• Journal of Power System Engineering
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• v.13 no.6
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• pp.63-69
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• 2009

The experiment was performed to check operating characteristics of fouling auto removal apparatus for multi pass type heat exchanger using ejector. The results showed as following. The ejector suction flow rate increased with the head of operating pump of ejector. Proper suction flow rate showed $7.2{\sim}10.2m^3/h$ for ball collection in case of pump head 35~50m. The head of ejector outlet pipe is below 4.1m in case of 40m, the head of operating pump of ejector to confirm ejector suction flow rate 8.4m3/h. Lattice space of ball separator is allowed 6~10.3mm in ranges of ball diameter are 15~25mm and when mass flow of cooling water is 3.0m/sec. Average of passing time of balls is 1.2~2.8sec depend on the velocity of flow and the size of balls.

• Environmental Engineering Research
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• v.13 no.3
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• pp.119-124
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• 2008

Ammonia is an inorganic compound that may cause severe odor problem. In this study the effectiveness of applying natural neutralizer to destroy and remove the odor-causing compound from gas streams was studied. Experimental result evaluated with a bench-scale apparatus via the neutralization of gas phase. This indicates that the natural neutralization depends on the gas concentration, gas residence time, temperature and pH. Removal efficiency of ammonia from gas stream was achieved by 95% using theconvection in the packed bed. This study proved the chemical neutralization technology was effective for controlling inorganic odor-causing compound.

• Journal of Environmental Health Sciences
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• v.43 no.6
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• pp.525-531
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• 2017

Objectives: The purpose of this experiment is to better understand the nitrogen and phosphorus removal ratio according to operating conditions in an iron electrolysis system consisting of an anoxic basin, aerobic basin, and iron precipitation apparatus. Methods: Iron electrolysis consists of an iron precipitation reactor composed of iron plates in oxic and anoxic basins. We studied the interrelation coefficient between T-N and T-P removal rates and F/M ratio, and the C/N ratio and BOD removal rate. Results: The F/M ratio and the T-N and T-P removal rate per unit area have interrelation coefficients of 0.362 and 0.603, respectively. The removal rate per MLVSS and the T-N and T-P removal rate per unit area have respective interrelation coefficients of 0.49 and 0.59. Conclusions: The removal rate of T-N and T-P increased with the increasing F/M ratio in the influent, and they also linearly increased in proportion to the C/N ratio of influent and BOD removal rate of the reactor.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.54 no.4
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• pp.198-202
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• 2005

The simulation of hydraulic pressure distribution of discharge tube with globular beads and the removal characteristics of Escherichia coli by the discharge tube with globular beads were estimated. The removal characteristic of Escherichia coli was related to the input voltage because the electric field is increased according to input voltage. As the passing amount of test water in discharge tube is increased, the removal ratio of Escherichia coli was increased because passing numbers of electric field section is increased.

• Journal of the Korean Applied Science and Technology
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• v.29 no.4
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• pp.653-658
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• 2012

There is an increasing interest in the use of electrochemical methods for the food waste treatment. The technologies using the electrochemical method provide ideal tools for approaching industrial and food wastes problems. Unlike other chemical treatments, the electrochemical systems do not make the volume of the secondary waste increase. The electrochemical methods can be operated with electrochemical apparatus and inorganic agent allow selective separation and recovery and even quieter than others. This study concerns design factors, electrode construction and wastewater treatment process of the electrochemical apparatus. The experiment of color, COD and BOD removal is much effective in using electrochemical method with ultrasonication and ozonation.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.425-433
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• 2011

In order to obtain optimum pre-treatment methods and improve T-N and T-P removal efficiencies, removal rates of pollutants in small-scale livestock wastewater treatment apparatus with water plant filtration bed or activated sludge tank were investigated. Based on the results from the optimum pre-treatment in small-scale livestock wastewater treatment apparatus, removal efficiencies of pollutants in livestock wastewater treatment plant with water plant filtration and activated sludge beds. The removal rates of COD, SS, T-N, and T-P in effluent were 83, 89, 63 and 87% in small-scale livestock wastewater treatment apparatus with water plant filtration bed, respectively. The removal rates of COD, SS, T-N, and T-P in effluent were 96, 95, 86 and 92% in small-scale livestock wastewater treatment apparatus with activated sludge tank, respectively. For increasing the COD, SS, T-N, and T-P removals in small-scale livestock wastewater treatment apparatus, the water plant filtration and activated sludge beds are recommended. In livestock wastewater treatment plant with water plant filtration ($1^{st}$ treatment) and activated sludge ($2^{nd}$ treatment) beds, the concentrations of COD, SS, T-N, and T-P in effluent were 39, 15, 42 and $1mg\;L^{-1}$, respectively. It was shown that the concentrations of COD, SS, T-N, and T-P met acceptable effluent quality standard for livestock wastewater. Based on the above results, the removal rates of COD, SS, T-N, and T-P in effluent were over 99.8, 99.9, 99.2, and 99.9% in livestock wastewater treatment plant, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.285-292
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• 2011

In order to develop livestock wastewater treatment technology by natural purification method, the optimum filter media in small-scale livestock wastewater treatment apparatus for treating livestock wastewater were studied. Removal rates of pollutants under different filter media were in the other of coarse sand ${\fallingdotseq}$ broken stone > zeolite > calcite for COD, zeolite >> broken stone ${\fallingdotseq}$ coarse sand ${\fallingdotseq}$ calcite for T-N, and calcite > coarse sand ${\fallingdotseq}$ broken stone ${\fallingdotseq}$ zeolite for T-P. Based on the above results, the optimum filter media was coarse sand in small-scale livestock wastewater treatment apparatus. To meet acceptable effluent quality standard for livestock wastewater and to improve T-N and T-P removal efficiencies, removal efficiencies of pollutants in small-scale livestock wastewater treatment apparatus with mixed filter media were studied. The removal rates of COD, SS, T-N and T-P in effluent were 84, 94, 65 and 98% in small-scale livestock wastewater treatment apparatus with mixed filter media, respectively. For increasing the T-N and T-P removals in small-scale livestock wastewater treatment apparatus, the mixed filter media are recommended.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.2
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• pp.278-284
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• 2011

To obtain optimum configuration method and livestock wastewater loading in small-scale livestock wastewater apparatus by natural purification method for treating livestock wastewater, the small-scale livestock wastewater apparatuses were constructed with 9 kinds of combined systems such as aerobic bed (ae)-anaerobic bed (an), ae-ae, ae-anoxic bed (ox), an-an, an-ae, an-ox, ox-ae, ox-an and ox-ox livestock wastewater treatment apparatuses. Under different configuration methods, the removal rate of COD in Ae-Ae and Ae-An livestock wastewater treatment apparatus was higher than that in other configuration methods. The removal rate of T-N in Ae-An livestock wastewater treatment apparatus was higher than that in other configuration methods. Removal rates of SS and T-P were not different regardless of configureation methods in small-scale livestock wastewater treatment apparatus. Under different livestock wastewater loading, the removal rates of pollutants were higher in the order of $50L\;m^{-2}\;day^{-1}{\fallingdotseq}100L\;m^{-2}\;day^{-1}\;>\;200L\;m^{-2}\;day^{-1}$. Therefore, optimum configuration method was Ae-An livestock wastewater treatment apparatus, and optimum livestock wastewater loding was $100L\;m^{-2}\;day^{-1}$ in small-scale livestock wastewater treatment apparatus.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.333-335
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• 2005

The simulation of electric field distribution of discharge tube with globular $ZrO_2$ and the removal characteristic of Escherichia coli by the discharge tube with globular $ZrO_2$ were estimated. The removal characteristic of Escherichia coli was related to the input voltage because the electric field is increased according to input voltage. As the particle size of $ZrO_2$ beads increased, the removal time of Escherichia coli was shortened due to the dielectric polarization of $ZrO_2$ beads.

• Journal of Korean Society of Water and Wastewater
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• v.27 no.3
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• pp.373-382
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• 2013

In this study, a biological odor treatment system was proposed to remove odor(foul smell) materials causing several problems in the closed sewage treatment plant. This odor treatment system was composed of a two-step biofilter system in one reactor. The two-step biofilter reactor was constructed with natural purification layer in upper part and artificial purification layer in lower part. The reed grasses of water purification plants were planted in the surface area and mixed porous ceramic media were filled with the lower part of biofilter reactor. By using the above experimental apparatus, the ammonia gas removal efficiency was attained to 98.3 % and the hydrogen sulfide gas removal efficiency was appeared more than 97.7 % which shows more effective than the conventional odor removal process.