• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.6
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• pp.587-591
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• 2019

Fine dust aerated in the atomsphere penetrates our lungs and blood lines through respiratory. Recent fine dust problems in Korea leads to development of various air purifiers. The researchers used this to study systems that could replace chemical filters. In order to compare the effect of the reduction of moss and conventional chemical filter(Hepa), a 1 cubic meter cube was prepared and the amount of the concentration of fine dust reduction was compared under controlled environment. Under the high concentration of fine dust, a test was done to figure out the reduction rate of the fine dust concentration by using air purification system with moss, hepa, and no filter. The air purification system(moss, hepa, and no filter) were operated 90 times in total, 30 times each. The test explains that the reduction of the fine dust amount and the rate of fine dust concentration. The results illustrate that the reduction of the amount fine dust was 138.93 after using air purification system with moss filter. In contrast, the usage of air purification system with hepa filter reduced the amount of fine dust to 76.57. And the air purification with no filter shows that the slight reduction of fine dust amount at 0.10. In the rate of fine dust concentration, moss filter was significantly higher than that of hepa, no filter (0.2379, 0.1298 and 0.0063 each). The results have confirmed that moss is effective in reducing fine dust concentration, and it is expected that with further improvement it can be used as a means to replace or supplement existing chemical filters in air purifier.

• Journal of Environmental Impact Assessment
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• v.14 no.4
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• pp.147-155
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• 2005

This study was designed to investigate the effect of plant as a botanical air purification on the indoor pollution by formaldehyde. Three indoor plants such as Dracaena marhginata, Spathiphyllum and Dracaena reflexa, were placed in the artificially contaminated reactor under laboratory condition. Both plant and soil effects on removal of formaldehyde from contaminated indoor air were observed. Reductions in the formaldehyde levels appeared to have been associated with soil medium factors as well as plant factors. The effect of soil on formaldehyde reduction was high in the early stage of the experiment and the results suggest that sorption could be more important factor than microbial degradation in the initial dissipation of contaminants in the soil. It was suggested that the effect of plant on formaldehyde reduction might be related to the plant species, total leaf surface area of plant, degree of contribution of soil medium, and exposed concentration level. The results of this study showed that air purification using plants is an effective means of reduction on indoor formaldehyde level, though, utilization of soil media with high sorption capacity and/or supplementary purifying aids were also suggested when the source is continuous or exposed concentration level is high.

• Carbon letters
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• v.6 no.1
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• pp.31-40
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• 2005

The carbon nanofibers (CNFs) were synthesized through the catalytic decomposition of hydrocarbons in a quartz tube reactor. The CNFs prepared from $C_3H_8$ at $550^{\circ}C$ was selected as the purification sample due to the higher content of impurity than that prepared from other conditions. In this study, we carried out the purification of CNFs by oxidation in air or carbon dioxide after acid treatment, and investigated the influence of purification parameters such as kind of acid, concentration, oxidation time, and oxidation temperature on the structure of CNFs. The metal catalysts could be easily eliminated from the prepared CNFs by liquid phase purification with various acids and it was verified by ICP analysis, in which, for example, Ni content decreased from 2.51% to 0.18% with 8% nitric acid. However, the particulate carbon and heterogeneous fibers were not removed from the prepared CNFs by thermal oxidation in air and carbon dioxide. This result can be explained by that the direction of graphene sheet in CNFs is vertical to the fiber axis and the CNFs are oxidized at about the similar rate with the impurity carbon.

• Journal of the korean Society of Automotive Engineers
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• v.4 no.1
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• pp.46-55
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• 1982

When an oxidizing catalytic converter which makes use of platium as a catalyst is employed by means if emission control of CO and HC gasoline engine, the effects of important factors for the purification efficiency, i.e engine speed and secondary air rate, on the reduction of CO and HC concentrations in the exhaust gas are studied experimentally. In the experiment, gasoline and LPG are used as a fuel, and the purification efficiency is examined and the results of both cases are compared with each other. The experimental results showed that the purification efficiency in the case of LPG is usually higher than that of gasoline, and the optimum values of engin speed and secondary air rate for maximum purification efficiency exist in common on both cases.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.3
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• pp.17-28
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• 2003

The objective of this study is to review and verify whether the functions and effect of roadside trees generally known in theory are actually realized in urban roads and how well they are performed if the function and effect are really realized. The study was conducted with a focus on air purification effect of roadside trees. The m헤r study result is as follows. First, calculation of air purification effect of roadside trees showed that it is minimal. However, 7.4 units of broad-leaved trees is necessary in order to purify $SO_2$ discharged by one passenger car and 1,803.3 trees to purify $NO_2$. Second, regarding pollutant absorption capacity, air pollutant absorption capacity increased as the number of rows planted gets higher (i.e., 2-row plantation absorbs pollutant better than I-row plantation). In particular, "2-row plantation + lower-level shrub + buffer green belt" was as eight times high as "I-row plantation" in absorption capacity. Third, out of 30 roads with over 8 lanes in 15 cities, only 33.3% or a total of ten roads in seven cities had a median strip. Out of these ten roads, nine roads were planted in a double-layer consisting forest trees, shrubs, ground plants (grass). Analysis showed that out of six tree species planted along these roads, about a half of them were weak to air pollution. Also, based on the outcome of this study, charging a "plantation due" when people purchase a new car, improving layout of roadside trees, and reinforcing plantation of air purification tree species when selecting tree species for roadside trees were proposed.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.29 no.6
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• pp.276-282
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• 2019

The purpose of this study was to analyze the structure of general filter using ultrafine filter (Profilter), dust collector filter, HEPA (HAPA-High Efficiency Particulate Air) filter, deodorized filters, etc. of air purifiers and to study new types of purified filters that can improve ultrafine dust, harmful gases, and sterilization cleanup performance. The study was also conducted by adding photocatalyst filters to the existing step-by-step filtration filter types, which were proposed in the design three coupling structure filters of the left and right UV-LED installation frames and the photocatalyst coating honeycomb frame. Future research is needed on the effect of photocatalyst filters. This study was to investigate the application and structure of photocatalyst filters to air purifiers.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.2
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• pp.109-114
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• 2022

Recently, since fine dust has become a serious social problem, air purifiers are in the spotlight as a countermeasure against this. Therefore, in this paper, we conducted R&D on the Smart Autonomous Moving Air Purifier System. The developed Smart Autonomous Moving Air Purifier can improve the limitations of the standard used area of existing air purifiers and perform an air purification function efficiently. In addition, we developed App and Web-based programs together for convenient use of Smart Autonomous Moving Air Purifier. Easily operate three air purification modes (Selection mode, Autonomous highest zone mode, Autonomous instant purification mode) through the App and conveniently monitor statistical values (Recent data, Total data, Warning) anywhere through the Web. And, we showed through test that the proposed Smart Autonomous Moving Air Purifier is more efficient than existing air purifiers.

• Air Cleaning Technology
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• v.29 no.4
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• pp.39-43
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• 2016

• Journal of the Semiconductor & Display Technology
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• v.20 no.4
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• pp.89-95
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• 2021

As the influence of fine dust on society spreads gradually, the public's interest in indoor air is increasingly rising. Air-purifying plants are drawing keen attention due to their natural purifying function enabled by plant physiology. However, as their fine dust reduction mechanism is limited to adsorption only, vegetation bio-filters that optimize purification effects through integration with air-conditioning systems is rising as an alternative. In accordance with the relevant standard test methods, this study looked into the fine dust reduction assessment method by air-conditioning airflow volume that can be used for the industrial spread of vegetation bio-filters. In the case of PM₁₀ at 300 ㎍/m³, it was in the order of EG-B(3,500CMH, 29 min.) < EG-A (2,500CMH, 37 min.) < CG(0CMH, 64 min.) for reaching the maintenance level (100 ㎍/m³) of publicly used facilities. For reaching the WHO Guideline(50 ㎍/m³) requirement, it was in the order of EG-B (51 min.) < EG-A (160 min.) < CG (170 min.). In the case of PM_2.5, it was in the order of EG-B (26 min.) < EG-A (33 min.) < CG (57 min.) for reaching the maintenance level (50 ㎍/m³) of publicly used facilities. It was in the order of EG-B (48 min) < EG-A (140 min) < CG (158 min) for reaching the WHO Guideline (25 ㎍/m³) requirement. The findings from the analysis showed that fine dust can be reduced most efficiently when the system is operated at 3,500CMH level. The limitation of this study is that due to the absence of a way of assessing the stress of plants in vegetation bio-filters, generating optimal air-conditioning air flow of the relevant system and economics analysis against the existing facility-type air purification system have been clarified, which should be explored further though follow-up studies.

• Journal of Korean Society for Atmospheric Environment
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• v.16 no.4
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• pp.373-380
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• 2000

A new type of photocatalyst plasma air purification filter for decomposition of some VOCs has been developed. The photocatalyst plasma air purification filter employs the pulsed discharge plasma as an energy source of TiO2. photocatalyst instead of UV light. In closed room(2m3) test removal efficiency of some VOCs was 80∼100% in 15∼24 hours. In the initial step of phptocatalyst plasma reaction. Acetone and Nitromethane etc were detected. But they were completely oxidized to CO2 and H2O.