Contributing Ratio of the Mechanical and the Physicochemical Actions to Washing Efficiency of Mineral Oil and Protein Soils

Woo, Ji Hyun,Kim, Jooyoun,Park, Chung Hee THE KOREAN FIBER SOCIETY 2014 FIBERS AND POLYMERS Vol.15 No.3

It was attempted to separate the detergency contributions from the mechanical actions and the physicochemical actions for two different types of soils. The mechanical washing efficiency was evaluated through the washing performed under the mechanical agitation, in the absence of detergent. The physicochemical washing efficiency was examined in the washing bath with detergent in the absence of mechanical agitation. Among the washing parameters, extended washing time and higher washing temperature were effective improving the mechanical and physicochemical washing efficiencies for mineral oil and carbon black. For blood soil, lower washing temperature and extended washing time enhanced the mechanical and physicochemical washing efficiencies. For the mineral oil, the presence of both mechanical and physicochemical actions led to the effective washing performance with synergistic effect. For the blood soil, mechanical actions were observed as more contributing than the physicochemical actions. The optimized washing program could be recommended as per the contributing ratios for the specific soil types, minimizing the energy consumption and detergent usage while achieving the washing performance.

Mechanical and physicochemical contribution in removal of different soil types on cotton fabric

Han, Hye Ree,Chung, Seung Eun,Kim, Jooyoun,Park, Chung Hee Sage Science Press 2015 Textile Research Journal Vol. No.

<P>The research was conducted to identify the optimal washing methods for three types of soils, in terms of washing efficiency and eco-efficiency. To this end, the mechanical action by the washer’s agitation and the physicochemical action by detergents were investigated for their respective contribution to the detergency of three kinds of artificial soils: oil, protein, and their mixture. In general, washing efficiency increased with the increased agitation speed and the amount of detergent use. Most of the washing conditions presented a positive synergistic effect when both the mechanical and physicochemical actions were applied simultaneously.</P><P>The contributing ratio of the physicochemical action was greater for oily soil than for other soil types, due to the effective rolling-up by the detergent for the oily soil. The contributing ratio attributable to the mechanical action was higher when the protein was present in the soil composition, and the mechanical contribution was compromised as detergent usage was increased. The washing condition with the largest synergy did not always correspond with the condition of the highest washing efficiency. Energy Efficiency for Detergency was increased in all soil types as the agitation speed increased. It is suggested that the washing method be determined considering (1) the level of soiling and the acceptable washing performance, (2) the synergistic effect of mechanical and physicochemical actions, and (3) the eco-efficiency of washing methods.</P>

세탁 및 옷감 신장에 따른 천마스크 제품의 여과효율 변화

김승원 ( Seung Won Kim ) 한국산업보건학회 (구 한국산업위생학회) 2017 한국산업보건학회지 Vol.27 No.2

Objectives: This study was designed to evaluate the changes in the particle filtration efficiencies of five cloth masks (4 plate types, 1 cup type) with an increasing number of machine washings and the degree of cloth expansion. Methods: NaCl aerosols were generated using an atomizer and passed through cloth masks in a dynamic aerosol chamber. Particle concentrations were measured both before and after for the cloth masks using an optical particle counter (OPC) in the size range of 0.3~10 μm. Results: In the original condition, the filtration efficiencies of the five cloth masks were A: 20.1%, B:30.9%, C: 25.0%, D: 26.5%, and E: 40.9%. As the number of washings increased in the order of one, two, and four times, the filtration efficiencies of cloth mask C increased. The filtration efficiency of A, D, and E increased after the first washing. With the exception of B, the filtration efficiency of cloth masks increased after the second washing and those of all cloth masks increased after the fourth washing. This might be caused by the fibers untangling from the yarn and being freed at one end. In this status, the packing density of the textile will not change, but the distances between fibers will increase, which might bring about an increase in filtration efficiency. When the cloth masks were extended by 10% and 20% in one direction, the filtration efficiencies of cloth masks B, D, and E decreased at 10% extension, and those of all cloth masks decreased at 20% extension. When the cloth masks were expanded by 10% and 20% in two directions, the filtration efficiencies of all cloth masks decreased by at least 34.7% at 10% extension, and by at least 60.9% at 20% extension Conclusions: The filtration efficiency of cloth masks could decrease after one to two machine washings, but will increase after four washings in comparison with their original performances. The filtration efficiency of cloth masks will decrease when they are expanded, such as when stretching over the nose during wearing status.

불소 오염토양의 기원별 오염특성을 파악하기 위한 광물학적 특성분석 및 세척효율평가

김현중,이윤진,이환 한국환경기술학회 2022 한국환경기술학회지 Vol.23 No.1

In this study, mineralogical characteristics analysis and extraction characteristics evaluation were performed to identify the contamination characteristics by origin of fluoride-contaminated samples of natural origin by granite mica and artificial fluoride-contaminated samples by waste gypsum fluoride of making fertilizer process. In samples of natural origin, mica, quartz, feldspar, fluorite, and amphibole showed the high mineral content in the order. Among them, mica, which is expected to be the causative mineral of fluorine contamination, consisted of muscovite, biotite, and lithium mica. In artificial fluoride-contaminated samples, quartz, plagioclase, illite, gypsum, sulfur, and wollastonite showed the highest mineral content in the order. Compared to the total mica content and fluorine concentration of the natural origin contaminated sample, a proportional linear relationship(R2=0.68) was shown, and this result is estimated to be the influence of natural origin by minerals in badlock not artificial contamination. When compared with the gypsum content and fluorine concentration of the artificially contaminated samples, a proportional linear relationship(R2=0.79) was shown, and the fluoride concentration was found to exceed the standard in all samples with a gypsum content of about 20 % or more. As a result of the washing efficiency test for each mica fluoride-contaminated sample, it was confirmed that the washing efficiency was relatively low with all washing agents less than 10 %, and hydrochloric acid(HCl) had the highest washing efficiency. In addition, the optimal hydrochloric acid(HCl) concentration was confirmed to be 1 M. As a result of the washing efficiency test for each washing agent for the fluorine-contaminated sample of a fertilizer factory, sodium hydroxide(NaOH) was confirmed to have the highest washing efficiency and showed about 1.5 times higher than hydrochloric acid(HCl). In addition, the optimal concentration of sodium hydroxide(NaOH) is judged to be suitable at 0.5 M, which showed a washing efficiency of 65.6 %. Based on the results of this study, it is intended to be used as a basic data for the development of soil remediation technology considering the method of proving the cause of fluoride-contaminated soil and the characteristics of contamination by origin.

The effect of fabric movement on washing performance in a front-loading washer II: under various physical washing conditions

Yun, Changsang,Park, Chung Hee Sage Science Press 2015 Textile Research Journal Vol. No.

<P>Fabric movements in a front-loading washer were observed at various conditions with respect to the type of fabric, the number of sheets, the fabric size and the wash spin speed in order to examine their effect on washing efficiency. Fabric movements were categorized into sliding, falling and rotating, which were expected to be influenced by the balance among the centrifugal force, the frictional force and the gravitational force. With increasing the number of sheets, the fabric size and the wash spin speed, fabrics had a tendency to move a longer distance along the drum wall, and thus the most frequent movement shifted from sliding or falling to rotating. The fabric movement patterns during the washing process that were varied according to the washing conditions had a direct effect on washing efficiency. The complex movement pattern, which showed the movements of sliding, falling and rotating by turns during the washing process, exhibited higher washing efficiency than the single movement pattern that represented only sliding or rotating repeatedly.</P>

The effect of fabric movement on washing performance in a front-loading washer III: Focus on the optimized movement algorithm

Yun, Changsang,Park, Chung Hee SAGE Publications 2016 Textile Research Journal Vol.86 No.6

<P>The objectives of this study were to investigate the correlation between fabric movement and washing efficiency in a front-loading washer and to make an algorithm for improving washing efficiency by optimizing fabric movements. A regression model between fabric movement and washing efficiency was made using 14 movement indexes. The angle change of the fabric gravity center, the speed difference between the drum and the fabric, and the shape factor were found to be determining factors for washing efficiency. Various kinds of wash spin speed were employed for making a complex movement algorithm, since it was found that turbulent or complex movement improves the washing efficiency. The optimal algorithm saved energy (25%) and time (27%), as well as achieving higher washing efficiency (4.8%).</P>

Performance Evaluation of Large-Capacity Decontamination System for Radioactively Contaminated Soil Using Water-Washing Treatment Technology

Suin Lee,Dohyung Kim,Jongyeol Lee 한국방사성폐기물학회 2023 한국방사성폐기물학회 학술논문요약집 Vol.21 No.2

Economical radioactive soil treatment technology is essential to safely and efficiently treat of high-concentration radioactive areas and contaminated sites during operation of nuclear power plants at home and abroad. This study is to determine the performance of BERAD (Beautiful Environmental construction’s RAdioactive soil Decontamination system) before applying magnetic nanoparticles and adsorbents developed by the KAERI (Korea Atomic Energy Research Institute) which will be used in the national funded project to a large-capacity radioactive soil decontamination system. BERAD uses Soil Washing Process by US EPA (402-R-007-004 (2007)) and can decontaminate 0.5 tons of radioactive soil per hour through water washing and/or chemical washing with particle size separation. When contaminated soil is input to BERAD, the soil is selected and washed, and after going through a rinse stage and particle size separation stage, it discharges decontaminated soil separated by sludge of less than 0.075 mm. In this experiment, the concentrations of four general isotopes (A, B, C, and D which are important radioisotopes when soil is contaminated by them.) were analyzed by using ICP-MS to compare before and after decontamination by BERAD. Since BERAD is the commercial-scale pilot system that decontaminates relatively large amount of soil, so it is difficult to test using radioactive isotopes. So important general elements such as A, B, C, and D in soil were analyzed. In the study, BERAD decontaminated soil by using water washing. And the particle size of soil was divided into a total of six particle size sections with five sieves: 4 mm, 2 mm, 0.850 mm, 0.212 mm, and 0.075 mm. Concentrations of A, B, C, and D in the soil particles larger than 4 mm are almost the lowest regardless of before and after decontamination by BERAD. For soil particles less than 4 mm, the concentrations of C and D decreased constantly after BERAD decontamination. On the other hand, the decontamination efficiency of A and B decreased as the soil particle became smaller, but the concentrations of A and B increased for the soil particle below 0.075 mm. As a result, decontamination efficiency of one cycle using BERAD for all nuclides in soil particles between 4 mm and 0.075 mm is about 45% to 65 %.

폐플라스틱 박편 재활용을 위한 초음파 해석

조영민,이주헌 경희대학교 2004 環境硏究 論文集 Vol.13 No.-

The washing efficiency of PET flakes by ultrasonic wave has been studied. It was observed that the washing efficiency was increased with increasing washing time but it was almost constant after 30 minutes. an increase in the strength of ultrasonic wave resulted in increasing the washing efficiency and a decrease in the washing efficiency was caused by increasing sample loading. It was observed that an addition of detergent quite increased e washing efficiency but it had a little relationship with the amount of detergent. It was concluded that the ultrasonic washing process was possibly to be used, since the maximum washing efficiency of 98% was obtained.

재활용을 위한 PET 박편의 초음파 세척율

이주헌 대구대학교 환경기술연구소 2004 미래환경기술 Vol.1 No.1

The washing efficiency of PET flakes by ultrasonic wave has been studied. It was observed that the washing efficiency was increased with increasing washing time but it was almost constant after 30 minutes. An increase in the strength of ultrasonic wave resulted in increasing the washing efficiency and a decrease in the washing efficiency was caused by increasing sample loading. It was observed that an addition of detergent quite increased the washing efficiency but it had a little relationship with the amount of detergent. It was concluded that the ultrasonic washing process was possible to be used, since the maximum washing efficiency of 98% was obtained. 초음파를 이용한 플레이크 형태의 폐플라스틱의 세척에 대한 처리효율을 조사하였다. 세척시간이 증가할수록 세척율도 증가하였으나 세척시간 30분 이후에는 세척율이 거의 일정하게 유지됨이 관찰되었다. 초음파의 강도가 증가할수록 세척율은 증가하였고, 시료 부하양의 증가는 세척효과의 감소를 초래하였다. 세제의 첨가는 세척율을 크게 증가시켰으나, 세제 주입량의 증가에 따른 세척율의 증가는 크지 않음이 관찰되었다. 최고 98%의 상당히 높은 처리효율을 얻을 수 있었으므로, 초음파 세척공정의 사용이 가능하다고 결론지어졌다.

표면 세척 시스템에 의한 유자의 미생물 및 잔류농약의 제거효과

성정민 ( Jung Min Sung ),권기현 ( Ki Hyun Kwon ),김종훈 ( Jong Hoon Kim ),정진웅 ( Jin Woong Jeong ) 한국식품저장유통학회(구 한국농산물저장유통학회) 2011 한국식품저장유통학회지 Vol.18 No.5

This study was conducted to assess the effects of the removal of pesticide residues and microorganisms from yuja (Citrus junos Sieb ex Tanaka) using a surface-washing system, under the following washing conditions: 0.11, 0.42, and 0.73 m/s spray rotation speeds; 0.6, 0.9, and 1.2 MPa water pressure and 0.046, 0.092, and 0.138 m/s conveying speeds. Tap-water treatment was used as the control. The washing efficiency when using squid ink was highly correlated with the conveying speed and the spray rotation speed. In addition, the highest washing efficiency was achieved when the water pressure was 0.9 MPa. The microorganisms were reduced to 0.40 log CFU/g for the tap-water treatment, and all the treatments, except those at the conveying speed of 0.138 m/s and the spray rotation speed of 0.11 rpm (6.07 log CFU/g), produced higher removal efficiencies compared with the tap-water treatment. Reductions of 2.20 and 2.05 log CFU/g were achieved at the spray rotation speeds of 0.42 and 0.73, respectively. The largest reductions were observed when the conveying speed was 0.046 m/s. Higher pesticide residue removal efficiency values were obtained at slower conveying speeds and higher spray rotation speeds. Higher than 50% removal efficiency was achieved when the spray rotation speed was 0.046 m/s for spirodichlofen, deltamethrin, benomyl, thiophanate-methyl, and acequinocyl. Especially, the removal efficiency for benomyl and thiophanate-methyl was more than 90%. It can thus be concluded that the pesticide residues in yuja can be effectively reduced by washing the latter with a less-than-0.092-m/s conveying speed and a higher-than-0.42-m/s spray rotation speed.