• 제목/요약/키워드: coagulation rate

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Study on Removal of DOC for Effluent from Nitrification and Denitrification Process with Zeolite by Combined Process of Coagulation and UF Membrane (제올라이트를 첨가한 질산화 탈질공정에서 응집과 UF공정을 이용한 처리수내 용존 유기물질 제거 연구)

  • Han, Jang Hyuk;Yoon, Tai Il;Cho, Kyung Chul;Song, Jea Yong
    • Journal of Korean Society of Water and Wastewater
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    • 제19권5호
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    • pp.537-546
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    • 2005
  • This study was carried out to evaluate EPS and SMP variation of sludge and effluent in nitrification and denitrification process with zeolite addition, a possible reduction of effluent DOC by URC(Ultra Rapid Coagulation) process. As a biological wastewater treatment result, EPS formation of both aeration and anoxic sludges are not affect by SRT variation. However, EPS concentration of sludges is higher in aeration tank than in anoxic tank by 6~8 mg EPS/ g VSS. Linear relationship between SMP to DOC indicates that SMP of bulk solution contributes to most of the biological treatment effluent DOC. DOC and turbidity removal efficiency was more improved with URC process than in a conventional coagulation. For pretreatment of UF filtration DOC removal was advanced by URC process than only UF filtration.

A Study on the Determination of Backwash Condition and Fouling in Coagulation/Ultrafiltration Membrane System (응집·한외여과 공정에서 역세척 조건 결정 및 막오염 특성에 관한 연구)

  • Moon, Seong-Yong;Lee, Sang-Hyup;Lee, Byoung-Cheun;Yun, Jong-Sub;Kim, Seung-Hyun
    • Journal of Korean Society on Water Environment
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    • 제22권1호
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    • pp.17-22
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    • 2006
  • This study is about backwash condition and membrane fouling at continuous coagulation/ultrafiltration process in water treatment. The capacity of pilot plant was $0.06m^3/d$. The result of the test, Backwash cycle time and duration time had a significant effect on the efficiency of system and backwash. Backwash duration time was determined to be fixed in 30 seconds for the system with more than 95% recovery rate, It needed 30 minute backwash frequency. During the continuous operation, membrane fouling was analyzed by determining the filtration resistance ($R_i$) and cake layer resistance ($R_c$). At the initial stage, filtration resistance highly influenced the fouling behavior. But after 1.5 hours, cake layer resistance became more important than filtration resistant.

Optimum Coagulation Conditions for Ceramic Microfiltration Membrane Process (세라믹 정밀여과막 공정을 위한 최적 응집조건)

  • Lim, Jae-Lim;Lee, Kyung-Hyuk;Lee, Young-Joo;Park, Jong-Yul
    • Membrane Journal
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    • 제22권2호
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    • pp.135-141
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    • 2012
  • This study was carried out to find the optimum coagulation conditions for ceramic microfiltration process of Y water treatment plant. When pH of raw water from Y Dam was adjusted to 7, the efficiency of coagulation was the best and the optimun dosage of coagulant was 3 mg/L(as $Al_2O_3$) for turbidity of raw water less then 10 NTU in Jar test. In mini module test, the decay rate of specific flux was the lowest when PAC (poly Aluminum Chloride) was used among coagulants and pH was adjusted to 7. The decay rate of specific flux for raw water turbidity of 10~30 NTU was greatly decreased with increase of dosage of coagulant (PAC) while the rate was not significantly decreased for turbidity more than 50 NTU. In conclusion, the optimum dosage of PAC (11% as $Al_2O_3$) was 30 and 50 mg/L for raw water turbidity of less than 10 NTU and more than 50 NTU, respectively. The dosage of PAC should be increased linearly 30 to 50 mg/L depending on raw water turbidity of 10 to 50 NTU.

Evaluation of Coagulation Characteristics of Fe(III) and Al(III) Coagulant using On-line Monitoring Technique (On-line 모니터링 기법을 이용한 Al염계와 Fe염계 응집제의 응집특성 평가)

  • Son, Hee-Jong;Yoom, Hoon-Sik;Kim, Sang-Goo;Seo, Chang-Dong;Hwang, Young-Do
    • Journal of Environmental Science International
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    • 제23권4호
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    • pp.715-722
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    • 2014
  • Effects of coagulation types on flocculation were investigated by using a photometric dispersion analyzer (PDA) as an on-line monitoring technique in this study. Nakdong River water were used and alum and ferric chloride were used as coagulants. The aim of this study is to compare the coagulation characteristics of alum and ferric chloride by a photometric dispersion analyzer (PDA). Floc growing rates ($R_v$) in three different water temperatures ($4^{\circ}C$, $16^{\circ}C$ and $30^{\circ}C$) and coagulants doses (0.15 mM, 0.20 mM and 0.25 mM as Al, Fe) were measured. The floc growing rate ($R_v$) by alum was 1.8~2.8 times higher than that of ferric chloride during rapid mixing period, however, for 0.15 mM~0.25 mM coagulant doses the floc growing rate ($R_v$) by ferric chloride was 1.1~2.3 times higher than that of alum in the slow mixing period at $16^{\circ}C$ water temperature. Reasonable coagulant doses of alum and ferric chloride for turbidity removal were 0.1 mM (as Al) and 0.2 mM (as Fe), respectively, and the removal efficiency of those coagulant doses showed 94% for alum and 97% for ferric chloride. The appropriate coagulant dose of alum and ferric chloride for removing dissolved organic carbon (DOC) showed about 0.3 mM (as Al, Fe) and at this dosage, DOC removal efficiencies were 36% and 44%, and ferric chloride was superior to the alum for removal of the DOC in water.

The Removal Characteristics of Organic Matter in Drinking Water Source by Coagulation and Ultrafiltration Process (응집 및 한외여과 공정에 의한 상수원수의 유기물질 제거 특성)

  • Kim, Hyun-Sik;Lim, Ji-Young;Kim, Jin-Han
    • Journal of the Korea Organic Resources Recycling Association
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    • 제26권2호
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    • pp.5-10
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    • 2018
  • This study was evaluated the characteristics of organic materials in the water source and the removal characteristics of organic materials by ultrafiltration including mixing and coagulation process. As a results of the study, it was found that the total organic carbon in the water source was mostly caused by the dissolved organic materials. As the specific ultraviolet absorbance value of the raw water was low, we found the soluble organic material has a high hydrophilic and low molecular material composition ratio. As a result of ultrafiltration experiment including mixing and coagulation process, the average removal rate of total organic carbon, dissolved organic carbon and ultraviolet absorbance at 254 were 37.9%, 30.3%, and 28.2%, respectively.

Model of Particle Growth in Silane Plasma Reactor for Semiconductor Fabrication (반도체 제조용 사일렌 플라즈마 반응기에서의 입자 성장 모델)

  • 김동주;김교선
    • Journal of the Korean Vacuum Society
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    • 제10권2호
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    • pp.275-281
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    • 2001
  • We used the discrete-sectional model to analyze the particle growth by coagulation of particles in silane plasma reactor, considering the Gaussian distribution function for particle charges. The effects of process conditions such as monomer size and mass generation rate of monomers on particle growth in plasma reactor were analyzed theoretically/ Based on the Gaussian distribution function of particle charges, the large particles of more than 40 nm in size are almost found to be charged negatively, but some fractions of small, tiny particles are in neutral state or even charged positively. As the particle size and surface area increase with time by particle coagulation, the number of charges per particle increases with time. As the large particles are generated by particle coagulation, the particle size distribution become bimodal. The results of discrete-sectional model for the particle growth in silane plasma reactor were in close agreement with the experimental results by Shiratani et al. [3] for the same plasma conditions. We believe the model equations for the particle charge distribution and coagulation between particles can be applied to understand the nano-sized particle growth in plasma reactor.

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Improvement of Cooling Water Quality by Coagulation and Sedimentation in Steel Mill (응집침전에 의한 제철공장 냉각수질향상)

  • Jo, Kwan-Hyung;Woo, Dal-Sik;Hwang, Byung-Gi;Lee, Seon-Ju;Park, Duck-Weon
    • Journal of Environmental Health Sciences
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    • 제35권5호
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    • pp.411-416
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    • 2009
  • This study was initiated to improve the cooling water quality by chemical coagulation and sedimentation in steel mills. Due to the inefficient flocculation in the settling tanks of blast furnace cooling water systems, the solid particles in the cooling water overflow accumulate and clog the cooling system. To protect the cooling water system from such fouling, proper flocculants must be continuously used. Laboratory tests were performed for the indirect cooling water system of a plate mill. The batch test in the gas scrubbing cooling water system of a blast furnace showed that the proposed coagulant was more effective for the improvement of coagulation and sedimentation than the existing one. During the tests, cationic flocculants were more effective than use of only an anionic flocculant. The suggested combination of anionic and cationic flocculants can probably improve the turbidity removal efficiency of the cooling water. Proper control of the overflow rate by the designed residence time would help turbidity removal efficiency in the settling tank. In addition, the settling can be enhanced by adopting rapid and slow mixing alternatively. Scale problems in blast furnace cooling water system were reduced to some extent by efficient settling.

Changes in the Laboratory Data for Cancer Patients Treated with Korean-medicine-based Inpatient Care

  • Yoon, Jeungwon;Cho, Chong-Kwan;Shin, Ji-Eun;Yoo, Hwa-Seung
    • Journal of Pharmacopuncture
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    • 제17권1호
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    • pp.20-26
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    • 2014
  • Objectives: The study aimed to determine changes in laboratory data for cancer patients receiving Korean medicine (KM) care, with a focus on patients' functional status, cancer-coagulation factors and cancer immunity. Methods: We conducted an observational study of various cancer patients in all stages admitted to the East-West Cancer Center (EWCC), Dunsan Korean Hospital of Daejeon University, from Mar. 2011 to Aug. 2011. All patients were under the center's multi-modality Korean-medicine-based inpatient cancer care program. The hospitalization stay at EWCC ranged from 9 to 34 days. A total of 80 patients were followed in their routine hematologic laboratory screenings performed before and after hospitalization. Patients were divided into three groups depending on the status of their treatment: prevention of recurrence and metastasis group, KM treatment only group, and combination of conventional and KM treatment group. The lab reports included natural killer cell count (CD16 + CD56), fibrinogen, white blood cell (WBC), lymphocytes, monocytes, neutrophil, red blood cell (RBC), hemoglobin, platelet, Erythrocyte Sedimentation Rate (ESR), and Eastern Cooperative Oncology Group (ECOG) performance status. Results: With a Focus on patients' functional status, cancer-coagulation factors and cancer immunity, emphasis was placed on the NK cell count, fibrinogen count, and ECOG scores. Data generally revealed decreased fibrinogen count, fluctuating NK cell count and decreased ECOG, meaning improved performance status in all groups. The KM treatment only group showed the largest decrease in mean fibrinogen count and the largest increase in mean NK cell count. However, the group's ECOG score showed the smallest decrease, which may be due to the concentration of late-cancer-stage patients in that particular group. Conclusions: Multi-modality KM inpatient care may have positive effect on lowering the cancer coagulation factor fibrinogen, but its correlation with the change in the NK cell count is not clear.

Effect of Gwaluzisiltang and Gwaluzisiltanggami on the Intravascular coagulation induced by Endotoxin in Rats (과루지실탕(瓜蔞枳實湯) 및 그 가미방(加味方)이 ENDOTOXIN으로 유발(誘發)된 혈전(血栓)에 미치는 영향(影響))

  • Lee, Sang-Gwon;Kim, June-Ki;Park, Weon-Hwan;Choi, Dal-Young;Moon, Jun-Jeun
    • The Journal of Dong Guk Oriental Medicine
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    • 제2권1호
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    • pp.107-125
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    • 1993
  • This study was performed to investigate the effects of Gwaluzisiltang and Gwaluzisiltanggami on the intravascular coagulation. The experimental group divided two groups : one group was the intravascular coagulation induced by endotoxin in rats, another group was the formation of paw edema by contusion in rats, and then these rats were treated with liquid extract of Gwaluzisiltang(Sample I) and Gwaluzisiltanggami(Sample II), which were administered orally. Then the numbers of platelets, concentration of fibrinogen, Prothrombin time and FDP(fibrin-fibrinogen degradation Products)were measured. The results were as follows : 1. The effects of the Intravascular coagulation 1) Platelet was increased significantly in the sample I compared with control group. 2) Fibrinogen was increased significantly in the sample I compared with control group. 3) Prothrombin time was shortened significantly in the sample I and more shortened in the sample II compared with control group. 4) FDP was decreased significantly in the sample I and more decreased in the samplem II compared with control group. 2. The effect of the formation of paw edema by contusion in rats. 1) The rate of paw edem was decreased significantly after five hours in the sample I 2) Platelet was increased significantly in the sample I compared with control group. 3) Fibrinogen was decreased in the sample I and sample II compared with control group, but it is not significant 4) Prothrombin time was shortened significantly in the sample II compared with control group. According to the above results, it is considered that the Gwaluzisiltang and Gwaluzisiltanggami seem to be applicable disease related to thrombosis, because they obtained significant effects on the experimental method which are based on the oriental medical theory-the principle of phlegm and blood stasis have the same source and disease (痰瘀同源, 痰瘀同病).

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Evaluation of a new method, "non-injection resection using bipolar soft coagulation mode (NIRBS)", for colonic adenomatous lesions

  • Mitsuo Tokuhara;Masaaki Shimatani;Kazunari Tominaga;Hiroko Nakahira;Takuya Ohtsu;Katsuyasu Kouda;Makoto Naganuma
    • Clinical Endoscopy
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    • 제56권5호
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    • pp.623-632
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    • 2023
  • Background/Aims: Endoscopic resection of all colorectal adenomatous lesions with a low complication rate, simplicity, and negative residuals is challenging. Hence, we developed a new method called "non-injection resection using bipolar soft coagulation mode (NIRBS)" method, adapted for colorectal lesions. In addition, we evaluated the effectiveness of this method. Methods: We performed NIRBS throughout a 12-month period for all colorectal lesions which snare resection was acceptable without cancerous lesions infiltrating deeper than the submucosal layer. Results: A total of 746 resected lesions were included in the study, with a 4.5 mm mean size (range, 1-35 mm). The major pathological breakdowns were as follows: 64.3% (480/746) were adenomas, and 5.0% (37/746) were intraepithelial adenocarcinomas (Tis lesions). No residuals were observed in any of the 37 Tis lesions (mean size, 15.3 mm). Adverse events included bleeding (0.4%) but no perforation. Conclusions: NIRBS allowed the resection of multiple lesions with simplicity because of the non-injection and without perforating due to the minimal burn effect of the bipolar snare set in the soft coagulation mode. Therefore, NIRBS can be used to resect adenomatous lesions easily, including Tis lesions, from small to large lesions without leaving residuals.