• Title/Summary/Keyword: pre treatment

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Sewage Sludge Treatment with Internal Recirculation and Diverse Pre-treatment Methods Using Combined Digestion Process (혼합 소화공정에서 내부반송과 다양한 전처리를 통한 하수 슬러지 처리)

  • Ha, Jeong Hyub;Choi, Suk Soon;Park, Jong Moon
    • Applied Chemistry for Engineering
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    • v.29 no.5
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    • pp.613-619
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    • 2018
  • In this study, various influent sludge pre-treatment methods and the internal recirculation of thickened sludge from effluents using a liquid/solid separation unit were adopted to investigate their effects on the sludge digestion and methane production in a combined mesophilic anaerobic and thermophilic aerobic sludge digestion process. A lab-scale combined sludge digestion process was operated during 5 phases using different feed sludge pre-treatment strategies. In phase 1, the feed sludge was pre-treated with a thermal-alkaline method. In contrast, in phases 2, 3 and 4, the internal recirculation of thickened sludge from the effluent and thermal-alkaline, thermal, and alkaline pre-treatment (7 days) were applied to the combined process. In phase 5, the raw sludge without any pre-treatment was used to the combined process. With the feed sludge pre-treatment and internal recirculation, the experimental results indicated that the volatile suspended solid (VSS) removal was drastically increased from phases 1 to 4. Also, the methane production rate with the thermal-alkaline pre-treatment and internal recirculation was significantly improved, showing an increment to 285 mL/L/day in phase 2. Meanwhile, the VSS removal and methane production in phase 5 were greatly decreased when the raw sludge without any pre-treatment was applied to the combined process. Considering all together, it was concluded that the combined process with the thickened sludge recirculation and thermal-alkaline pre-treatment can be successfully employed for the highly efficient sewage sludge reduction and methane gas production.

A Study on the Wave Formation and Hair Damage Levels Relating to the Uses of Treatments for Heat Permanent Waves

  • Kim, Kwan-Ok;Kim, Sung-Nam
    • Journal of Fashion Business
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    • v.12 no.6
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    • pp.1-10
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    • 2008
  • Public interest in healthy hairs gets growing as damaged hairs are seen more frequently with the generalization of heat permanent waves. For this study, experiments have been conducted to understand the influences on the changes in physical and morphological features of wave forms and damaged hairs, by collecting virgin hairs from the women in their mid-20's, who had not experienced chemical applications, and by dividing the applications of heat perm hair treatments, PPT(for pre-treatment) and LPP(for post-treatment), into the pre-treatment, the post-treatment, the pre & post-treatment, and the non-treatment. For the wave formations, curl waves were investigated by the bare eyes using the pictures taken by a digital camera. For the comparison of physical features, the experiments of tensile strength and elongation were done and their mean values were found. For the observations of morphological features, the pictures were taken by SEM for comparison. As for the findings, regarding the curl wave shapes of hairs, the most even and elastic S curl was formed in the case of non-treatment. In the physical features, both of the tensile strength and elongation showed a decreasing tendency in line with the hair damage levels, and the case of the pre & post-treatment indicated the tendency most similar to the control group. In the morphological features of the cuticle, observed with an SEM, the pre-treatment showed the higher possibility of reducing the cuticle damages than the post-treatment did. LPP was found to play the role of protective membrane for the post-treatment, and the pre & post-treatment turned out to reduce most effectively the cuticle damages.

Disintegration of Flotation Scum in Food Wastewater Using Thermo-Alkaline Pretreatment (열-알칼리 전처리를 통한 음식물류 폐수 부상 스컴의 가용화)

  • Choi, Jae-Min;Lee, Chae-Young
    • Journal of Hydrogen and New Energy
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    • v.26 no.1
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    • pp.71-78
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    • 2015
  • This study was performed to optimize the integrated thermal-alkali pre-treatment of flotation scum for the enhanced biodegradability. The optimum conditions of the integrated thermal-alkali pre-treatment were obtained using response surface methodology. The disintegration degree of carbohydrate (69.2%) and protein (57.3) were estimated under the optimum conditions. Although the optimum conditions were different, the disintegration degrees were similarly. A fermentative hydrogen batch test was conducted to evaluate the hydrogen production from scum with and/or without. The maximum hydrogen production from scum with pre-treatment was of 0.64 mol H2/mol hexoseadded, which about 1.4 times higher than without pre-treatment.

Effect on DTP process by cotton treated with atmosphere plasma

  • Hong, Tae-Il;Yoon, Suk-Han;Park, Jae-Bum;Koo, Kang
    • Proceedings of the Korean Society of Dyers and Finishers Conference
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    • 2009.03a
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    • pp.43-44
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    • 2009
  • Fabrics for Digital Textile Printing (DTP) are different from it of general textile printing. It is necessary to pre-treatment of chemical agents for desired quality. But this process does not correspond with simplification of DTP processing. In this research, we pre-treated of cotto is necessary to pre-treatment of chemical agents for desired quality. But this process does not correspond with simplification of DTP processing. In this research, we pre-treated of cotton fabric for DTP by atmosphere plasma treatment and we understood that pre-treatment of fabric by atmosphere plasma treatment was more simple DTP process.

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Influence of Cotton Pre-Treatment on Dyeing with Rubia cordifolia extracts for Cotton (면의 전처리 방법이 Rubia cordifolia 추출물의 염색성에 미치는 영향)

  • Bum Hoon Lee
    • Textile Coloration and Finishing
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    • v.35 no.1
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    • pp.1-7
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    • 2023
  • In this study, the influence of pre-treatment(bleaching, mercerization by liquid ammonia and caustic soda) on cotton fabrics were investigated on dyeing Rubia cordifolia extracts. Aluminium Sulfate, Iron(Ⅱ) Sulfate Heptahydrate, Copper(Ⅱ) Sulfate Pentahydrate, Tin(Ⅱ) Sulfate, Manganese(Ⅱ) Chloride Tetrahydrate were used as mordanting agents. K/S value and washing fastnesses of the dyed cotton fabrics pretreated under different conditions were investigated. The K/S values were increased in the order of bleaching, liquid ammonia and mercerization pre-treatment. It was found that the pre-treatment conditions did not significantly affect the color change. The colorfastness to washing of most of all dyed fabrics were over grade 4 regardless of pre-treatment condition.

Mineralogical Transformation of Gold-silver Bearing Sulfide Concentrate by Mechanochemical Activation, and their Gold-silver Leaching with Non-cyanide Solution (기계적-화학적 활성화에 따른 금-은-정광의 광물학적 상변화와 비-시안 용매에 의한 금-은 용출 향상)

  • Kim, Bong-Ju;Cho, Kang-Hee;Oh, Su-Ji;Choi, Nag-Choul;Park, Cheon-Young
    • Journal of the Mineralogical Society of Korea
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    • v.27 no.3
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    • pp.115-124
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    • 2014
  • In order to leach Au and Ag from gold-silver bearing sulfide concentrate, the sulfide concentrate was ground in a ball mill for a dry pre-treatment and a wet pre-treatment process. Mineralogical studies and thiourea leaching experiments were carried out with the pre-treated sulfide concentrate. The results of the pre-treatment with the concentrate samples showed the mean particle size and iso-electrical potential was smaller in the dry pre-treatment sample than in the concentrate sample, and the contents was lower in the wet pre-treatment sample than in the dry pre-treatment sample. In XRD analysis, amorphous properties were only shown in the wet pretreatment sample. The results of the concentrate sample leaching experiments showed that the best Au, Ag leaching parameters were when the addition of thiourea was at a 1.0 g concentration, ferric sulfate was 1.0 M, sulfuric acid was 2.0 M and the leaching temperature was at $60^{\circ}C$. The Au, Ag leaching rate was always much greater and faster with the wet pre-treatment samples than with the dry pre-treatment samples. Accordingly, it is expected that more Au, Ag can be leached in an eco-friendly methodology using wet pre-treatment. The pre-treatment could be improved with an optimized grinding additive reagent and through researching grinding time in future non-cyanide processes.

Changes in Physicochemical Characteristics of Apple Pre-Treated with Sugar and Salt for Manufacturing Apple Jangachi (사과장아찌 제조를 위한 전처리공정 중 절임원에 따른 사과의 이화학적 특성변화)

  • Oh, Chul-Hwan
    • Culinary science and hospitality research
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    • v.23 no.8
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    • pp.98-105
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    • 2017
  • The purpose of this study was to investigate changes in physicochemical properties of apples pre-treated differently with salt and sugar for apple Jangachi. When salt was used, moisture content was decreased by 28.41% to 57.67% at 24 hours and maintained an average 56.92% after 24 hours. However, when sugar was used, moisture content decreased steadily to 41.14% (60h). The pH of the apple pre-treated with salt decreased from pH 4.42 to pH 3.63 at 12 hours. However, in the case of apples pre-treated with sugar, pH decreased from pH 4.52 to pH 4.19 after 48 hours, but was not statistically significant. Conversely, total acidity of apple pre-treated with salt increased from 11.46% to 0.35% during 72 hours. But total acidity of apple pre-treated with sugar decreased to 0.11% at 24 hours and maintained. Sugar content of apple pre-treated with salt increased to 33.1% at 12 hours and maintained. Conversely, in case of sugar pre-treatment, sugar content of apple pre-treated with sugar increased steadily to 45.12% at 72 hours. Salinity of apple pre-treated with salt increased sharply to 15.74% during 24 hours. Lightness ($L^*$) of apple pre-treated sugar was not different from the control group. But apple pre-treated salt decreased slightly. Yellowness ($b^*$) was higher than the control group regardless of pre-treatment group. Sensory evaluation revealed that sugar pre-treatment apples were highly evaluated for flavor, taste, chewiness and overall acceptance.

Ginsenoside Changes in Red Ginseng Manufactured by Acid Impregnation Treatment

  • Kim, Mi-Hyun;Hong, Hee-Do;Kim, Young-Chan;Rhee, Young-Kyoung;Kim, Kyung-Tack;Rho, Jeong-Hae
    • Journal of Ginseng Research
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    • v.34 no.2
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    • pp.93-97
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    • 2010
  • To enhance the functionalities of ginseng, an acid impregnation pre-treatment was applied during red ginseng processing. Acetic, ascorbic, citric, malic, lactic, and oxalic acid were used for the acid impregnation treatment, and total and crude saponin concentrations and ginsenoside patterns were evaluated. Total and crude saponin contents of red ginseng pre-treated by acetic, ascorbic, and citric acid were similar to those of red ginseng without pre-treatment, whereas lactic, malic, and oxalic acid pre-treatment caused a reduction of total and crude saponin in red ginseng. From the high performance liquid chromatography analysis of ginsenosides, increased $Rg_3$ density was shown in red ginseng pre-treated by acetic, ascorbic, and citric acid impregnation. In the case of lactic, malic, and oxalic acid pre-treatment, increased $Rg_1$ density was observed in red ginseng. Increased $Rg_1$ and $Rg_3$ contents due to acid impregnation during red ginseng processing may contribute to improving bioactive functionalities of red ginseng.

Research of Possibility of Carrageenan as DTP Pre-treatment Thickening Agent for Cellulosic Fabric (카라기난(Carrageenan)의 셀룰로오스 직물 DTP 전처리 호제로써의 가능성 연구)

  • Ki, Saetbyul;Seo, Hyeji;Hong, Jinpyo;Yoon, Seokhan;Shin, Kyung
    • Textile Coloration and Finishing
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    • v.27 no.4
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    • pp.318-326
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    • 2015
  • A pre-treatment process is essential for getting high quality of digital textile printing(DTP). In this study, we have studied three kinds of carrageenan polymer(k-, ${\lambda}$-, i-Carrageenan) as a pre-treatment thickening agent for the first time. Alginate polymer was also examined and its results were compared with that of the three kinds of carrageenan polymer. To confirm the performance of each thickening agent, we examined for a sharpness, color strength and fastness(washing, rub, light). The result showed that ${\lambda}$-Carrageenan has superior property in sharpness with low viscosity and i-Carrageenan was excellent in the color strength among the pre-treatment agents. Washing fastness to color change and staining for the all samples were 4 or 4-5 grade. Both dry and wet rubbing fastness of the samples were 4-5 grade. However, ${\lambda}$-Carrageenan coated sample has the lowest grade in light fastness. As a result, we found the possibility of carrageenan polymer as pre-treatment agent.

Technology Trend on the Increase of Biogas Production and Sludge Reduction in Wastewater Treatment Plants: Sludge Pre-treatment Techniques (하수처리장 바이오가스 생산 증대와 슬러지 감량화에 관한 기술분석: 슬러지 전처리 기술)

  • Cho, Il Hyoung;Ko, In Beom;Kim, Ji Tae
    • Korean Chemical Engineering Research
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    • v.52 no.4
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    • pp.413-424
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    • 2014
  • The potential of using the biogas as energy source has long been widely recognised and current techniques are being developed to upgrade the technical quality and to enhance energy efficiency. The objective of this paper is to present efficient and effective pre-treatment methods of increasing the amount of produced biogas in anaerobic digestion of activated sludge treatment process. The paper also presents a review of the effect on biogas production between pre-treated and raw sludge, and also put forward the advantages and disadvantages of each pre-treatment method.