• Air Cleaning Technology
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• v.11 no.1 s.40
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• pp.27-35
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• 1998

• Air Cleaning Technology
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• v.21 no.2
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• pp.79-79
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• 2008

• Air Cleaning Technology
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• v.15 no.3 s.58
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• pp.92-93
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• 2002

• Clean Technology
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• v.7 no.4
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• pp.225-242
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• 2001

Cleaning process is necessary for machining parts or manufacturing finished products in the industry. Most of domestic and foreign companies are now trying to adopt environment-friendly aqueous cleaning agents instead of CFC-113 and 1,1,1-TCE which are ozone-depleting substances. However, the aqueous cleaning system has a disadvantage due to its generation of lots of waste water since the system utilizes water in cleaning and rinsing processes. Thus, it is very important that monitoring and recycling technologies of the cleaning solution and the rinse water should be introduced in the aqueous cleaning system in order to minimize generation of waste water and to maintain its cleaning performance for a quite long time. In this paper, the cleaning agents utilized in the aqueous cleaning system and cutting oils which are main contaminants were examined and analyzed. And the monitoring and recycling technologies of the aqueous cleaning system which can be employed in the industrial fields were also reviewed and evaluated.

• Journal of Applied Reliability
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• v.18 no.1
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• pp.66-71
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• 2018

Purpose: Performance recovered from SCR through cleaning was studied, measuring differential pressure, NOx reduction efficiency, fuel consumption and engine power before and after cleaning. Ideal cleaning intervals are proposed based on SCR mileage and differential pressure. SCR endurance and reliability improvements through cleaning were studied through physicochemical testing of SCR durability at 43,000km 50,000km, and 110,000km respectively. Methods: Engine power, fuel consumption and exhaust gas were measured using engine full load tests and ND-13 MODE by installing the SCR before cleaned at total engine mileages of 400,000 km, 300,000km and 200,000km. The same tests were performed after cleaning the SCR catalytic converter. Endurance and reliability of the SCR cleaning was studied through the same test by SCR catalyst after each 43,000km 50,000km, 110,000km, durability test on SCR cleaning. Conclusion: We confirmed the low-performance of the SCR due to clogging is restored by SCR cleaning technology. The NOx reduction efficiency was restored to 82%, 86% and 88% from 69%, 72% and 79%. As well as the NOx reduction efficiency, it was confirmed that the engine power, fuel consumption and back pressure was restored to fresh SCR levels. As a result of the durability and reliability achieved through SCR cleaning, we confined the appearance and reduction efficiency through visual inspection and ND-13 MODE are similar to new SCR catalysts. Finally, it was judged that there was no change in performance even when driving the SCR without cleaning throughout the 100,000 km mileage warranty.

• Journal of Fisheries and Marine Sciences Education
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• v.25 no.6
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• pp.1336-1347
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• 2013

The marine algal flora assemblages settled on the artificial seaweed reefs in Jeju-do before and after rocky cleaning were investigated during summer and the early succession of seaweeds attached to the test panels on the structures of the artificial reef after rocky cleaning were observed by visual observations and under the dissecting microscope in order to evaluate the effects of this rocky cleaning operation. Species composition and algal biomass on the Bboolsamgak-typed seaweed artificial reefs before and after rocky cleaning were measured and compared before and after rocky cleaning. Before rocky cleaning in July 2012, only nine algal species had existed on the Bboolsamgak-typed seaweed artificial reefs, however, twenty algal species occurred on the seaweed artificial reefs after rocky cleaning in July 2013. Particularly, 15 species among them in July 2013 were not found in July 2012 and they seemed to occur newly on the artificial reefs. A large quantity of algal biomass increased in July 2013 after rocky cleaning. Based on the importance value, there was a drastic change in the dominant species between July 2012 and July 2013 after rocky cleaning. By dissecting micrographs, an epiphytic diatom, Licmophora sp. and flagellates, were observed on the 9th day. A chlorophyte, Ulothrix flacca was observed after 14 days, Ulva pertusa, Bryopsis pulmosa, crustose coralline algae, and Cladophora spp. were after one month. After two months, a significant species succession was observed from three previous chlorophyte species to crustose coralline algae existed as a dominant species on the panels. In this study, however, any brown algae were not found until three months in the early seaweed succession. All above results indicates that the rocky cleaning is a very efficient method for the establishment of macroalgal assemblages on the artificial reefs.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.3
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• pp.285-291
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• 2011

Membrane fouling is an unavoidable phenomenon and major obstacle in the economic and efficient operation under sea water reverse osmosis (SWRO). When fouling occurs on the membrane surface, the permeate quantity and quality decrease, the trans-membrane pressure (TMP) and operation costs increase, and the membrane may be damaged. Therefore, chemical cleaning process is important to prevent permeate flow from decreasing in RO membrane filtration process. This study focused on proper chemical cleaning condition for Shuaibah RO plant in Saudi Arabia. Several chemical agents were used for chemical cleaning at different contact time and concentrations of chemicals. Also autopsy analysis was performed using LOI, FT-IR, FEEM, SEM and EDX for assessment of fouling. Specially, FEEM analysis method was thought as analyzing and evaluating tool available for selection of the first applied chemical cleaning dose to predict potential organic fouling. Also, cleaning time should be considered by the condition of RO membrane process since the cleaning time depends on the membrane fouling rate. If the fouling exceeds chemical cleaning guideline, to perfectly remove the fouling, certainly, the chemical cleaning is increased with membrane fouling rate influenced by raw water properties, pre-treatment condition and the point of the chemical cleaning operation time. Also choice of cleaning chemicals applied firstly is important.

• Journal of the Korean Applied Science and Technology
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• v.27 no.2
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• pp.107-113
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• 2010

The object of this research is to conform of practicable possibility and recycling of producing junk after citrus fruits is processed. With extracting d-limonene oil that have 70~90% a component of oil out of junk citrus peel, making certain the about 12000ppm concentration of it. Limonene derived from citrus in jeju using conventional synthetic detergents can be replaced with the development of environmentally friendly natural detergent investigated the possibility. Mostly due to ocean dumping, disposal and cause environmental problems by recycling natural citrus cleaner alternative to the research conducted on the possibility. Cleaning efficiency with temperature did not affect the largest concentrations were able to identify the difference between cleaning efficiency. At least 10% of the d-limonene oil could be from the cleaning performance, increasing the concentration of the cleaning efficiency was increased in size. Ultrasonic is very high removal efficiency under the conditions shown in the cause of pure self-generated ultrasonic cleaning power as co-effects of d-limonene oil appears to chemical cleaning effect of ultrasonic cavitation occurs in the physical cleaning effect due to a combination of synergistic stability is maximized by low concentrations of d-limonene oil in a short time showed an excellent cleaning ability. Having the ability of cleaning at the same time, considering the side recycling in the junk citrus peels reflects possibility of basic materials utility eco-friendly in the skin soap, bath soap, cosmetics etc, through ability of exclusion a contaminant in based cleaning effect(EC) it can prospect substitution effect environmentally in the pre existence synthetic detergents.

• Journal of the Semiconductor & Display Technology
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• v.23 no.2
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• pp.114-122
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• 2024

NF₃, Chamber cleaning gas, has a high Global Warming Potential (GWP) of 17,000, causing significant greenhouse effects. Reducing gas usage during the cleaning process is crucial while increasing the cleaning Rate and reducing cleaning standard deviation (Stdev). In a previous study with a 6-inch PECVD chamber, a multiple linear regression analysis showed that Power and Pressure had no significant effect on the cleaning Rate because of their P-values of 0.42 and 0.68. The weight for Flow is 11.55, and the weights for Power and Pressure are 1.4 and 0.7. Due to the limitations of the research equipment, which differed from those used in actual industrial settings, it was challenging to assess the effects in actual industrial environment. Therefore, to show an actual industrial environment, we conducted the cleaning process on a 12-inch PECVD chamber, which is production-level equipment, and quantitatively analyzed the effects of each variable. Power, Pressure, and NF3 Flow all had P-values close to 0, indicating strong statistical significance. The weight for Flow is 15.68, and the weights for Power and Pressure are 4.45 and 5.24, respectively, showing effects 3 and 7 times greater than those with the 6-inch equipment on the cleaning rate. Additionally, we analyzed the cleaning Stdev and derived that there is a trade-off between increasing the cleaning Rate and reducing the cleaning Stdev.

• Journal of Conservation Science
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• v.27 no.3
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• pp.333-344
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• 2011

Cleaning of foreign matter and corrosion products on surface among conservation treatment of iron artifacts is an important part for looking up a original form. The sand blaster is the most popular equipment when it removes the foreign matter and corrosion products on iron artifacts surface. Current foreign matter and corrosion products equipment, which mostly uses, is sand blaster. Glass dust which sprayed from sand blaster is harmful and causing environmental pollution. In order to solve these problems, we investigated the $CO_2$ snow cleaning that use a eco-friendly equipment to apply for cleaning foreign matter and corrosion products on surface of iron artifacts. It examined by using sand blaster and $CO_2$ snow cleaning to aged steel coupon and iron artifacts. In case of aged steel coupon, the result showed that the sand blaster and $CO_2$ snow cleaning methods were similar to the degrees of cleaning foreign matter and corrosion products, through surface roughness, color measurement and SEM. $CO_2$ snow cleaning applied to aged steel coupons weren't worn out the surface in comparison with sand blaster by SEM. When applied to the iron artifacts, power nozzle of the $CO_2$ snow cleaning was an excellent cleaning effect that surface wern't worn out in comparison with sand blaster. And, it showed that internal structure change of metal was no found before and after cleaning by X-ray radiography. Consequently, we confirmed that cleaning of the sand blaster and power nozzle of $CO_2$ snow cleaning were similar to the effect. But, it's very careful to use this method because of high outlet pressure of power nozzle for applying to the iron artifacts. As a result of experiments, it could be found that the cleaning methods should be selected depending on internal state of the artifacts.