• 대한가정학회지
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• 제37권2호
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• pp.113-126
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• 1999

In order to investigate the detergency effect of stained cotton and PET fabric, respectively, these fabrics stained with solid soils such as carbon black, liquid paraffin, and fat and examined the detergency effect in the optimum washing condition. The evaluation of washing efficiency of washed fabrics studied by using the surface reflectance measurement before and after washing treatment. The maximum detergency effect of stained cotton and PET fabric obtained in the mixed washing liquor-bleachig agen(ml)/concentrated washig agent(g/l). To obtain the excellent detergency effect, 2-step washing treatment, pre-washing by bleaching agent only and washing by concentrated detergent, is preferred. In comparing the detergency of polyester and cotton fabric, the detergency of stained polyester fabric superior than that of stained cotton fabric because of the difference of adhesive force between soil material and fabric in preparing soled stained fabric. In this study, we also studied the degree of fabric damage by the measurement of tensile strength change. From the results of the tensile strength measurement, the damage of washed fabric before and after washing treatment was nearly changed.

• 한국지하수토양환경학회지:지하수토양환경
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• 제12권3호
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• pp.17-22
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• 2007

납으로 오염된 실제 토양을 처리하기 위해 토양세척기술의 적용성을 평가하였다. 세척제로는 염산을 사용하였으며, 0.2 M 염산을 사용하여 고액비 1:3으로 하여 10분간 접촉하여 2회 세척하여준 결과 96%의 제거율을 보였다. 세척액과 토양의 접촉시간을 5분에서 120분까지 증가하였을 때, 제거효율은 69.3%에서 81.9%로 증가하였다. 입경별 토양세척 효율은 온도와 교반시간에 영향을 받았으며, 20분 이상 교반하여 준다면, 0.075 mm 이하, 0.075 mm-2.0 mm, 2.0-4.0 mm 의 입경별 토양에서는 모두 99%의 제거효율을 보였다. 이상의 결과는 본 연구에 사용된 납 오염 토양은 토양세척기술을 적용하여 효과적으로 처리할 수 있는 것을 의미한다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제25권1호
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• pp.74-83
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• 2020

In this study, the effect of hydrochloric acid (HCl) concentrations on removal efficiency and chemical forms of heavy metals in dredged sediment during acid washing was investigated. The removal efficiencies of Zn, Cu, Pb, Ni and Cd by acid washing were 18.4-92.4%, 7.2-83.7%, 9.4-75%, 8.1-53.4% and 34.4-70.8%, respectively. Overall, the removal efficiencies of heavy metals were remarkably enhanced with the increase of the acid strength. However, the removal efficiencies for 0.5 and 1.0 M HCl were comparable, and both cases met the Korean soil contamination standard. Based on the sequential extraction results, concentration of the exchangeable fraction (F1), the most labile fraction, increased whereas concentrations of the other fractions decreased with increasing acid strength. Particularly, the carbonate (F2) and Fe/Mn oxides (F3) fractions drastically decreased by using 0.5 M or 1.0 M HCl. The current study results verified that acid washing could effectively reduce heavy metal concentrations and its potential mobility in dredged sediments. However, the study also found that acid washing may cause significant increase in bioavailable fraction of heavy metals, suggesting the need to evaluate the changes in chemical forms of heavy metals by acid washing when determining the acid strength to be applied.

• 한국토양환경학회지
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• 제2권1호
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• pp.99-107
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• 1997

본 연구에서는 일련의 회분식 규모의 실험을 통해 소수성 유기오염물질로 오염된 토양에 토양세척기법을 적용함에 있어서 필요한 최적의 운전조건을 도출하고 세척후 분리된 상등액중에 포함된 유기오염물질 및 세척제를 유기용매를 이용하여 효율적으로 분리.회수하기 위한 방안을 모색하고자 하였다. 사용된 계면활성제는 토양과 결합될 우려가 적은 비이온계 계면활성제중 독성이 거의 없으며 국내에서 대량 생산되어 수급이 원활한 계면활성제를 선별하여 소수성 유기오염물질인 n-dodecane(4,000mg/kg dny Soil)으로 오염된 토양에 대해 세척시간, 계면활성제 용액의 농도, 진탕비, 온도 등에 따른 세척효율의 변화를 조사하였다. 실험결과 계면활성제의 HLB(hydrophile-liphophile balance)값이 MSR(molar solubility ratio) 값과 함께 토양세척시 중요한 변수로 작용하였다. HLB값이 낮아 유탁액을 형성하지 못하는 OA-5나 sophorolipid는 10% 이내의 극히 낮은 세척효율을 보였다. 그러나 안정된 유탁액을 형성하는 HLB값 범위내에서는 소수성 유기오염물질에 대한 액상실험에서의 용해도가 큰 계면활성제가 유리하였다. 높은 HLB값을 갖는 OA-14는 OA-9 보다 안정된 유탁액을 형성하지만 용해도에 대한 지표인 MSR값이 OA-9보다 작아 약 20%정도의 낮은 세척효율을 보였다. 안정된 유탁액을 형성하는 동시에 용해도가 높은 OA-9용액이 단독으로 쓰일 때는 최대 60%정도의 세척효율을 보였다. 또한 OA-9세척유출수로부터 유기용매인 벤젠을 이용하여 anthracene을 회수하고자 하는 경우, 세척유출수의 온도를 $30^{\circ}C$, pH는 2로 조절하는 것이 회수 효율 측면에서 바람직하다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권5호
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• pp.26-33
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• 2015

Batch experiments were performed to investigate the feasibility of a surfactant-enhanced soil washing process for soils heavily contaminated with crude oil in Kuwait. TPH concentration of the contaminated soil was 223,754 mg/kg, sampled from the bottom of a vaporized oil extraction pond in the Burgan reservoir field. Commercialized eight nonionic surfactants (Tween and Tergitol series) were used to measure the aqueous solubility for the crude oil. Among them, two Tergitol surfactants were used to evaluate the TPH removal efficiency of the surfactant-enhanced soil washing for heavily contaminated Kuwait soil. The solubility of the crude oil in surfactant solution was in the order Tergitol 15-S-7 > Tergitol 15-S-9 > Tergitol 15-S-12 > Tween-80 > Tween-20 > Tween-60, which showed that the crude oil solubilities of the Tergitol series were higher than those of the Tween series. The TPH removal efficiencies of 2% and 5% Tergitol 15-S-9 solution were 59% and 65%, respectively. Because the residual TPH concentration in the washed soil was still higher than the clean-up level (10,000 mg/kg), the soil washing process was repeated five times. After the fifth washing, the residual TPH concentration in the soil went down to 7,680 mg/kg and its removal efficiency was 97%.

• 한국지하수토양환경학회지:지하수토양환경
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• 제16권1호
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• pp.71-81
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• 2011

Cause of contamination in the study area nearby Jang Hang Refinery is dust scattering in refinery stack, and soil washing treatment is one of the proper technologies for soil remediation in this area. Site conditions frequently limit the selection of a treatment process. A treatment technology may be eliminated based on the soil classification or physicochemical characteristics of soil. This study was assessed the soil washing efficiency by conducting of soil characteristic analysis in the vicinity of Jang Hang Refinery Stack within a 2 km radius. Also, it was decided about remedial range with comparative analysis of As in soil by Korean Standard Test Method before/after revision, whereupon As concentration in soil showed a increasing tendency after revision. As a result, the soil washing using the size separation of soil was determined through identifying of As species in the soil. In this site, only particle size distribution and water content of soil can provide the initial means of screening for the potential use of soil washing.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2008년도 하계학술대회 논문집
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• pp.571-573
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• 2008

Conventional drum washing machine is divided by amount of laundry on 3 step. Because that, this method is arisen in case of washing smaller amount of laundry than each weight during same time. In other words, power is wasted by unnecessary washing time. In this paper, exact quantity of laundry is obtained by using inertia estimator considering features of drum washing machine, unnecessary washing time is decreased by selection proper washing time, thus the algorithm that increase efficiency by reducing power consumption is proposed.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2005년도 전력전자학술대회 논문집
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• pp.36-38
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• 2005

In home appliances, electric energy is optimally controlled by using power electronics technology, creating a comfortable environment in terms of energy saving, low sound generation, and reduced time consumption. Usually simplicity and robustness make the three phase induction motor attractive for use in domestic appliance, including washing machines. Two main types of domestic washing machine have evolved. We focus on the front loading machine favored in Europe, which has a horizontal drum axis. The efficiency improvement in home appliances is very important for customers. Induction motor efficiency can be improved by means of loss reduction, which can be realized by motor selection and design, improvement of the waveforms supplied by power Inverter, utilizing a suitable control method. So this paper describes the architecture and feature of washing machine fed induction motor drive under minimizing losses vector control.

• 분석과학
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• 제37권1호
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• pp.1-11
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• 2024

In agricultural households cultivating vegetables and fruits, the use of various pesticides to protect crops from diseases and pests or to control weeds is widely practiced enhancing quality and productivity. However, pesticides can pose a threat to consumer health by remaining on the food surface or migrating into the food interior. Households commonly peel off skins, wash with water, or use chemical methods to remove foreign substances including residual pesticides on the food surface. In this study, we measured the washing rate by comparing the pesticide concentrations before and after washing in the leafy vegetable perilla leaves and the fruits strawberries and apples, which were intentionally exposed to pesticides. We compared washing rates using tap water, a baking soda solution, and a commercially available food-specific cleaning solution. The target pesticides for analysis were azoxystrobin, bifenthrin, boscalid, difenoconazole, flubendiamide, and indoxacarb, and the residual pesticide analysis was performed using GC-MS/MS or LC-MS/MS. The removal rates of pesticides were highest with the food-specific cleaner, followed by baking soda and tap water in order.

• 한국지하수토양환경학회지:지하수토양환경
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• 제19권4호
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• pp.45-51
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• 2014

In accordance with the view on remediated soil as a resource, this study assessed the applicability of soil washing with the neutral phosphate for remediation of arsenic (As)-contaminated soil. Three soil samples of different land uses (i.e., rice paddy, upland field and forest land) were collected from the study site, and the aqua regia-extractable As concentrations were 59.2, 30.8 and 53.1 mg/kg, respectively. Among the neutral phosphate reagents, ammonium phosphate showed the highest As washing efficiency. The optimized washing condition was 2-hr washing with 0.5M ammonium phosphate solution (pH 6) and soil to liquid ratio of 1 : 5. The extraction efficiencies of As did not guarantee the residual soil As concentrations to satisfy the Korea soil regulatory level (i.e., Worrisome level) in the three soil samples. To enhance washing efficiency, the As-contaminated soil was submerged in washing solution (1 : 1, w/v) for 24 hr and 1-hr washing with 0.5M ammonium phosphate solution was tested. As extraction efficiencies of 36.1 (rice paddy), 21.4 (upland field) and 26.4% (forest land) were attained, which satisfied the Worrisome level for Region 1 (25 mg/kg of As) in rice paddy, but not in upland field and forest land.